Clinical science and molecular medicine. Supplement最新文献

1. Case records were examined of 66 patients who died while being treated for high blood pressure. 2. The possibility that benzothiadazine diuretics may have some deleterious as well as beneficial effects was investigated. 3. It is possible that the thiazides may have some adverse clinical effects, at least in females, with regard to the incidence of myocardial infarction in hypertensive patients.

1. In 27 severe primary hypertensive patients nifedipine (10 mg), administered orally, induced prompt (-21% of control at 30 min) and persistent (-17% at 120 min) fall of mean arterial pressure mediated through reduction of peripheral vascular resistance with rise of cardiac output. 2. The sublingual route (nine cases) showed more rapid onset of action and equal antihypertensive effectiveness. 3. In five patients with hypertensive crisis and acute left ventricular failure, the drug strikingly reduced systemic and pulmonary arterial pressures and relieved pulmonary oedema. 4. Prompt efficacy, ease of administration, absence of important side effects indicate that nifedipine may be a useful therapeutic agent in severe hypertension and in critical conditions that require rapid lowering of blood pressure.

1. Vitamin B12 absorption was measured in 18 patients with tropical malabsorption. 2. Absorption was particularly impaired in patients with severe mucosal lesions. 3. Sequential measurements with 57Co- and 58Co-labelled vitamin B12 were made before and 48 h after the start of tetracycline therapy. A rapid improvement (on average 22% increase in absorption) occurred in four of six patients with marked mucosal lesions. Further improvement occurred in four of five patients measured after 4 weeks' tetracycline, including the two who failed to improve initially. 4. These rapid changes in vitamin B12 absorption after antibiotics occur too early to be due to mucosal recovery and suggest that bacterial metabolism is an important factor in the malabsorption in these patients.

1. We have studied the acute effects of frusemide, triamterene and amiloride on potassium exchange, the action potential and mechanical function of isolated rabbit myocardium. 2. Potassium exchange in the myocardium was unaltered by these diuretics. 3. Frusemide and amiloride did not affect the action potential of rabbit papillary muscles. Triamterene caused a transient shortening of the action potential. 4. Frusemide and triamterene did not alter myocardial mechanical function in rabbit papillary muscles or the interventricular septum. Amiloride caused a reduction of about 5% in developed tension in two out of three papillary muscles.

1. Conversion of thyroxine into tri-iodothyronine and reverse tri-iodothyronine in intact cells was studied with isolated renal tubules prepared by collagenase digestion. 2. Conversion of thyroxine into tri-iodothyronine and reverse tri-iodothyronine increased progressively for at least 90 min. 3. Studies of tri-iodothyronine production from increasing amounts of thyroxine revealed that the thyroxine to tri-iodothyronine conversion is saturable. 4. Iodine and carbimazole had no effect on the thyroxine to tri-iodothyronine conversion. 5. 6-Propyl-2-thiouracil had a direct non-competitive inhibitory effect on the conversion of thyroxine into tri-iodothyronine with a 75% inhibition of the conversion at a propylthiouracil concentration within the therapeutic range in vivo. Propylthiouracil also inhibited the net formation of reverse tri-iodothyronine from thyroxine at a similar propylthiouracil concentration, as well as inhibiting the subsequent degradation of reverse tri-iodothyronine.

1. Angiotensin II receptors from rat adrenal gland and myometrium were studied during variation of sodium intake. 2. In both target-tissues low Na+ diet increased the number of receptors whereas a high Na+ diet did not modify the adrenocortical receptors but increased the number of uterine receptors. 3. Deoxycorticosterone and one kidney Goldblatt hypertension were associated with a decrease in the number of adrenal receptors. 4. Alterations of angiotensin II receptors alone cannot explain satisfactorily the variations of sensitivity of target-cells to angiotensin II during sodium balance changes.

1. Plasma adrenaline and noradrenaline were measured in supine and upright positions in 27 essential hypertensive patients and in 12 age-matched control subjects. 2. Plasma adrenaline was markedly increased in a large proportion of patients, compared with control subjects, either in supine or in upright positions, whereas no significant differences were found in plasma noradrenaline. 3. Six hypertensive patients were chronically treated with beta-adrenoreceptor-blocking agents (five with propranolol and one with pindolol). Plasma noradrenaline was not significantly changed in the supine position but was markedly increased on standing in four out of six patients. Plasma adrenaline was decreased in five out of six patients either in suprine or upright positions. 4. These findings support the view that the adrenergic system participates in the mechanism of essential hypertension.