Different techniques and materials used in the surgery of chronic otitis media have been evaluated in a large clinical experience at Semmelweis University, Budapest. Data from 1572 operations performed during the last 5 years (1983-1988) are summarized. In the 870 non-cholesteatomatous processes (55.3%), mastoidectomies and tympanoplasties were performed, with the latter primarily using temporalis fascia and cortical bone. Out of the 250 cholesteatoma cases (15.9%), one-fourth was solved by a primary wall-up technique followed by a second stage revision and tympanoplasty within 1.5 years later.
{"title":"Our experiences at Semmelweis University with different techniques and materials in the surgery of chronic otitis media.","authors":"A Hirschberg, O Ribàri","doi":"10.1007/BF00463574","DOIUrl":"https://doi.org/10.1007/BF00463574","url":null,"abstract":"<p><p>Different techniques and materials used in the surgery of chronic otitis media have been evaluated in a large clinical experience at Semmelweis University, Budapest. Data from 1572 operations performed during the last 5 years (1983-1988) are summarized. In the 870 non-cholesteatomatous processes (55.3%), mastoidectomies and tympanoplasties were performed, with the latter primarily using temporalis fascia and cortical bone. Out of the 250 cholesteatoma cases (15.9%), one-fourth was solved by a primary wall-up technique followed by a second stage revision and tympanoplasty within 1.5 years later.</p>","PeriodicalId":8300,"journal":{"name":"Archives of oto-rhino-laryngology","volume":"246 5","pages":"277-9"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/BF00463574","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13731506","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M Jorissen, B Van der Schueren, H Van den Berghe, J J Cassiman
Dissociated human nasal epithelial cells from nasal polyps were cultured in Ham's F12-DME 1/1 supplemented with NU-serum 10%, choleratoxin (10 ng/ml), retinoic acid (10(-7) M) and antibiotics. In monolayer cultures, the epithelial cells grew to confluency on collagen gels, became squamous, and lost their cilia within 2-6 weeks. In suspension cultures, epithelial cell sheaths formed stable vesicles and aggregates. These maintained a respiratory-type morphology and normal ciliary activity for over 6 months. When deciliated, squamous cells from monolayer cultures were brought in suspension, a respiratory-type morphology with cilia reappeared. This in vitro ciliogenesis resulted in normal and coordinated ciliary activity observed for more than 5 months.
{"title":"The preservation and regeneration of cilia on human nasal epithelial cells cultured in vitro.","authors":"M Jorissen, B Van der Schueren, H Van den Berghe, J J Cassiman","doi":"10.1007/BF00463582","DOIUrl":"https://doi.org/10.1007/BF00463582","url":null,"abstract":"<p><p>Dissociated human nasal epithelial cells from nasal polyps were cultured in Ham's F12-DME 1/1 supplemented with NU-serum 10%, choleratoxin (10 ng/ml), retinoic acid (10(-7) M) and antibiotics. In monolayer cultures, the epithelial cells grew to confluency on collagen gels, became squamous, and lost their cilia within 2-6 weeks. In suspension cultures, epithelial cell sheaths formed stable vesicles and aggregates. These maintained a respiratory-type morphology and normal ciliary activity for over 6 months. When deciliated, squamous cells from monolayer cultures were brought in suspension, a respiratory-type morphology with cilia reappeared. This in vitro ciliogenesis resulted in normal and coordinated ciliary activity observed for more than 5 months.</p>","PeriodicalId":8300,"journal":{"name":"Archives of oto-rhino-laryngology","volume":"246 5","pages":"308-14"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/BF00463582","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13732837","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
B Guerrier, G Balmigere, J P Daures, J G Lallemant, Y Guerrier
We report a retrospective study of 161 cases of vestibular or epilaryngeal cancer treated by horizontal laryngectomy. The different factors affecting prognosis were analyzed statistically. Three groups were distinguished according to the size and primary site of the tumor: (1) a group with a very poor prognosis, which included patients with large tumors of the epilarynx; (2) a group with an average prognosis, which included small tumors of the epilarynx and large tumors with their primary site in the vestibule; (3) a group with a favorable prognosis which included tumors classified as T1 or T2 that were initially located in the vestibule.
{"title":"Cancer of the laryngeal vestibule. A retrospective study of 161 cases.","authors":"B Guerrier, G Balmigere, J P Daures, J G Lallemant, Y Guerrier","doi":"10.1007/BF00463599","DOIUrl":"https://doi.org/10.1007/BF00463599","url":null,"abstract":"<p><p>We report a retrospective study of 161 cases of vestibular or epilaryngeal cancer treated by horizontal laryngectomy. The different factors affecting prognosis were analyzed statistically. Three groups were distinguished according to the size and primary site of the tumor: (1) a group with a very poor prognosis, which included patients with large tumors of the epilarynx; (2) a group with an average prognosis, which included small tumors of the epilarynx and large tumors with their primary site in the vestibule; (3) a group with a favorable prognosis which included tumors classified as T1 or T2 that were initially located in the vestibule.</p>","PeriodicalId":8300,"journal":{"name":"Archives of oto-rhino-laryngology","volume":"246 5","pages":"378-81"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/BF00463599","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13733493","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
R A Tange, H L Kieviet, J von Marle, D Bagger-Sjöbäck, W Ring
Vancomycin has been successfully used clinically for many years. Although early reports found ototoxicity to be a side effect of this antibiotic, later studies could not confirm this. For this reason we have started an experimental study in an animal model on the ototoxic effects of vancomycin. We now report the results of this study. Fourteen healthy Mongolian gerbils were treated with intraperitoneal injections of vancomycin (80 mg/kg per day) for a 2-week period. Before and after treatment each animal's hearing was evaluated by evoked response audiometry. Post mortem the cochleae were investigated by scanning electron microscopy in Amsterdam and by microdissection with surface preparations (hair cell counting) in Stockholm. The results of this study show that there is no clear evidence for the existence of ototoxicity due to vancomycin in this dosage.
{"title":"An experimental study of vancomycin-induced cochlear damage.","authors":"R A Tange, H L Kieviet, J von Marle, D Bagger-Sjöbäck, W Ring","doi":"10.1007/BF00457456","DOIUrl":"https://doi.org/10.1007/BF00457456","url":null,"abstract":"<p><p>Vancomycin has been successfully used clinically for many years. Although early reports found ototoxicity to be a side effect of this antibiotic, later studies could not confirm this. For this reason we have started an experimental study in an animal model on the ototoxic effects of vancomycin. We now report the results of this study. Fourteen healthy Mongolian gerbils were treated with intraperitoneal injections of vancomycin (80 mg/kg per day) for a 2-week period. Before and after treatment each animal's hearing was evaluated by evoked response audiometry. Post mortem the cochleae were investigated by scanning electron microscopy in Amsterdam and by microdissection with surface preparations (hair cell counting) in Stockholm. The results of this study show that there is no clear evidence for the existence of ototoxicity due to vancomycin in this dosage.</p>","PeriodicalId":8300,"journal":{"name":"Archives of oto-rhino-laryngology","volume":"246 2","pages":"67-70"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/BF00457456","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13870818","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Over the last 40 years sporadic reports have appeared in the otolaryngological and neurological literature describing techniques and applications of laryngeal electromyography. Despite considerable refinements in methodology and instrumentation over that time laryngeal electromyography has not been widely adopted in routine clinical practice. This paper describes a simple, reliable and reproducible technique which has been employed by the author over a 15-year period. The indications for laryngeal electromyography are reviewed and the technique currently used is briefly described with reference to alternative techniques. The usefulness of the information obtained by this examination is discussed.
{"title":"Laryngeal electromyography.","authors":"R L Blair","doi":"10.1007/BF00463604","DOIUrl":"https://doi.org/10.1007/BF00463604","url":null,"abstract":"<p><p>Over the last 40 years sporadic reports have appeared in the otolaryngological and neurological literature describing techniques and applications of laryngeal electromyography. Despite considerable refinements in methodology and instrumentation over that time laryngeal electromyography has not been widely adopted in routine clinical practice. This paper describes a simple, reliable and reproducible technique which has been employed by the author over a 15-year period. The indications for laryngeal electromyography are reviewed and the technique currently used is briefly described with reference to alternative techniques. The usefulness of the information obtained by this examination is discussed.</p>","PeriodicalId":8300,"journal":{"name":"Archives of oto-rhino-laryngology","volume":"246 5","pages":"395-6"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/BF00463604","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13827201","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D Loidolt, H Mangge, M Wilders-Truschnig, F Beaufort, K Schauenstein
In about 10% of patients who are operated on for chronic sinusitis, an aspergilloma is found in the affected paranasal sinus. In order to detect possible underlying immune defects, 25 patients with aspergillomas were subjected to an immunological screening program. The data obtained were compared with those of patients with non-mycotic chronic sinusitis and healthy controls. Total lymphocyte counts and immunoglobulin levels were normal in both groups with sinusitis. However, leukocyte subset analyses using membrane fluorescence revealed a significant decrease of CD11+ cells (macrophages, monocytes and natural killer-cells) in both types of sinusitis. Furthermore, a markedly enhanced frequency of CD25+ cells (interleukin 2-receptor-bearing cells), was observed in patients with the aspergillomas. Additionally, peripheral blood lymphocytes in both groups of patients showed a significant reduction in the proliferative response to both T- and B-cell mitogens, with the values for the mitogens ConA and PHA being significantly lower in the aspergilloma patients as compared to those with non-mycotic sinusitis. This lack of lymphocyte stimulation in the aspergilloma group was also manifest in skin tests to recall antigens. These first data suggest that there is an immune deficiency in patients with chronic sinusitis caused by Aspergillus fumigatus. Further studies are needed to clarify if this defect is the cause or the result of the mycotic infection.
{"title":"In vivo and in vitro suppression of lymphocyte function in Aspergillus sinusitis.","authors":"D Loidolt, H Mangge, M Wilders-Truschnig, F Beaufort, K Schauenstein","doi":"10.1007/BF00463585","DOIUrl":"https://doi.org/10.1007/BF00463585","url":null,"abstract":"<p><p>In about 10% of patients who are operated on for chronic sinusitis, an aspergilloma is found in the affected paranasal sinus. In order to detect possible underlying immune defects, 25 patients with aspergillomas were subjected to an immunological screening program. The data obtained were compared with those of patients with non-mycotic chronic sinusitis and healthy controls. Total lymphocyte counts and immunoglobulin levels were normal in both groups with sinusitis. However, leukocyte subset analyses using membrane fluorescence revealed a significant decrease of CD11+ cells (macrophages, monocytes and natural killer-cells) in both types of sinusitis. Furthermore, a markedly enhanced frequency of CD25+ cells (interleukin 2-receptor-bearing cells), was observed in patients with the aspergillomas. Additionally, peripheral blood lymphocytes in both groups of patients showed a significant reduction in the proliferative response to both T- and B-cell mitogens, with the values for the mitogens ConA and PHA being significantly lower in the aspergilloma patients as compared to those with non-mycotic sinusitis. This lack of lymphocyte stimulation in the aspergilloma group was also manifest in skin tests to recall antigens. These first data suggest that there is an immune deficiency in patients with chronic sinusitis caused by Aspergillus fumigatus. Further studies are needed to clarify if this defect is the cause or the result of the mycotic infection.</p>","PeriodicalId":8300,"journal":{"name":"Archives of oto-rhino-laryngology","volume":"246 5","pages":"321-3"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/BF00463585","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13828928","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We measured the pure-tone air and bone conduction hearing of 359 randomly selected otologically normal urban preschool children in Finland at the average age of 5.2 years. Children with otoscopically verified middle ear pathology or abnormal impedance audiometry were not included in this sample. The mean air conduction thresholds varied from 16.6 dB at 0.125 kHz to 6.6 dB at 2 kHz, and the mean bone conduction thresholds from 6.0 dB at 0.25 kHz to 0.7 dB at 4 kHz. The pure-tone average (of air conduction thresholds at 0.5, 1 and 2 kHz) of all the ears was 7.6 dB. The distribution of single air conduction hearing thresholds at the frequencies from 0.25 kHz to 4 kHz showed that 66%-75% were at the 5-10 dB level.
{"title":"Pure-tone hearing thresholds in otologically healthy 5-year-old children in Finland.","authors":"T Rahko, P Karma","doi":"10.1007/BF00456654","DOIUrl":"https://doi.org/10.1007/BF00456654","url":null,"abstract":"<p><p>We measured the pure-tone air and bone conduction hearing of 359 randomly selected otologically normal urban preschool children in Finland at the average age of 5.2 years. Children with otoscopically verified middle ear pathology or abnormal impedance audiometry were not included in this sample. The mean air conduction thresholds varied from 16.6 dB at 0.125 kHz to 6.6 dB at 2 kHz, and the mean bone conduction thresholds from 6.0 dB at 0.25 kHz to 0.7 dB at 4 kHz. The pure-tone average (of air conduction thresholds at 0.5, 1 and 2 kHz) of all the ears was 7.6 dB. The distribution of single air conduction hearing thresholds at the frequencies from 0.25 kHz to 4 kHz showed that 66%-75% were at the 5-10 dB level.</p>","PeriodicalId":8300,"journal":{"name":"Archives of oto-rhino-laryngology","volume":"246 3","pages":"137-41"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/BF00456654","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13897282","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Chemically induced esthesioneuroepitheliomas (ENE) in rats were subjected to tissue culture experiments, biochemical evaluations for catecholamines and chromosomal analyses. The most conspicuous cytogenetic finding was a C1 marker chromosome in addition to numerical and structural chromosomal aberrations. Regarding the overwhelming similarity between human ENE and experimentally induced ENE, similar cytogenetic aberrations in its human counterpart are postulated. Biochemically, no catecholamines or their metabolic precursors could be identified, thus distinguishing ENE from sympathetic neuroblastomas. No keratin-positive cells could be found in the primary tumor or in the cell cultures studied, thus showing that immunohistology can be a valuable tool for differentiating ENE from anaplastic carcinomas.
{"title":"Chemically induced esthesioneuroepithelioma: a cytogenetic, cell culture and biochemical investigation with implications for tumor histogenesis.","authors":"M Vollrath","doi":"10.1007/BF00457457","DOIUrl":"https://doi.org/10.1007/BF00457457","url":null,"abstract":"<p><p>Chemically induced esthesioneuroepitheliomas (ENE) in rats were subjected to tissue culture experiments, biochemical evaluations for catecholamines and chromosomal analyses. The most conspicuous cytogenetic finding was a C1 marker chromosome in addition to numerical and structural chromosomal aberrations. Regarding the overwhelming similarity between human ENE and experimentally induced ENE, similar cytogenetic aberrations in its human counterpart are postulated. Biochemically, no catecholamines or their metabolic precursors could be identified, thus distinguishing ENE from sympathetic neuroblastomas. No keratin-positive cells could be found in the primary tumor or in the cell cultures studied, thus showing that immunohistology can be a valuable tool for differentiating ENE from anaplastic carcinomas.</p>","PeriodicalId":8300,"journal":{"name":"Archives of oto-rhino-laryngology","volume":"246 2","pages":"71-8"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/BF00457457","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13801165","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Experience with antibody-dependent, cell-mediated cytotoxicity (ADCC) has shown that antibody can increase the localization and killing capacity of lymphocytes. We tested the possibility of improving the activity of lymphokine-activated killer cells (LAK) on human tumor using the subrenal capsule assay in nude mice. The tumors were first grown in the renal capsule space and the effector cells injected later. In the model experiment we used M21 melanoma and monoclonal antibody against melanoma-associated antigen GD3. This antibody increases the tumor inhibitory activity of LAK cells from healthy donors in comparison to LAK alone. We have been able to prove the clinical relevance of such an approach. Tumor bioptic material from five tumor patients was tested with various monoclonal antibodies, following which the highly reactive antibodies were selected and incubated with the patient's LAK cells. Such pretreated LAK cells have a high growth-inhibitory effect on autologous tumor growing in the renal capsule space of the test mice.
{"title":"Use of the subrenal capsule assay to measure antibody-dependent, cell-mediated cytotoxicity against head and neck tumors.","authors":"R Kau, C Kürten, H Kumazawa, P Koldovsky","doi":"10.1007/BF00456660","DOIUrl":"https://doi.org/10.1007/BF00456660","url":null,"abstract":"<p><p>Experience with antibody-dependent, cell-mediated cytotoxicity (ADCC) has shown that antibody can increase the localization and killing capacity of lymphocytes. We tested the possibility of improving the activity of lymphokine-activated killer cells (LAK) on human tumor using the subrenal capsule assay in nude mice. The tumors were first grown in the renal capsule space and the effector cells injected later. In the model experiment we used M21 melanoma and monoclonal antibody against melanoma-associated antigen GD3. This antibody increases the tumor inhibitory activity of LAK cells from healthy donors in comparison to LAK alone. We have been able to prove the clinical relevance of such an approach. Tumor bioptic material from five tumor patients was tested with various monoclonal antibodies, following which the highly reactive antibodies were selected and incubated with the patient's LAK cells. Such pretreated LAK cells have a high growth-inhibitory effect on autologous tumor growing in the renal capsule space of the test mice.</p>","PeriodicalId":8300,"journal":{"name":"Archives of oto-rhino-laryngology","volume":"246 3","pages":"165-8"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/BF00456660","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13896394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In view of recent controversies concerning the preservation of hearing in acoustic neurinoma surgery, we examined the courses of the vestibular and cochlear nerve fibers in 12 intact acoustic neurinomas studied in our department. Due to its lack of specificity, the Luxol fast blue stain was found to be inadequate for our study of the nerve fibers. In contrast, Verhoeff's stain proved to be satisfactory when combined with a highly specific immunohistochemical technique. There were macroscopically visible adherences between the tumor and the cochlear nerve in 9 out of the 12 specimens. From those specimens, histological sections were obtained in which both the cochlear nerve and tumor could be clearly identified. In these specimens the cochlear nerve was involved in the tumoral process and there was no clear cleavage plane between the nerve and the tumor. However, all these patients suffered only from minimal losses of hearing as a result of their tumors.
{"title":"The involvement of the cochlear nerve in neurinomas of the eighth cranial nerve.","authors":"G Forton, L Moeneclaey, F Declau, J Marquet","doi":"10.1007/BF00456658","DOIUrl":"https://doi.org/10.1007/BF00456658","url":null,"abstract":"<p><p>In view of recent controversies concerning the preservation of hearing in acoustic neurinoma surgery, we examined the courses of the vestibular and cochlear nerve fibers in 12 intact acoustic neurinomas studied in our department. Due to its lack of specificity, the Luxol fast blue stain was found to be inadequate for our study of the nerve fibers. In contrast, Verhoeff's stain proved to be satisfactory when combined with a highly specific immunohistochemical technique. There were macroscopically visible adherences between the tumor and the cochlear nerve in 9 out of the 12 specimens. From those specimens, histological sections were obtained in which both the cochlear nerve and tumor could be clearly identified. In these specimens the cochlear nerve was involved in the tumoral process and there was no clear cleavage plane between the nerve and the tumor. However, all these patients suffered only from minimal losses of hearing as a result of their tumors.</p>","PeriodicalId":8300,"journal":{"name":"Archives of oto-rhino-laryngology","volume":"246 3","pages":"156-60"},"PeriodicalIF":0.0,"publicationDate":"1989-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1007/BF00456658","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"13619887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}