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91.
92.
This report uses cross-sectional results from the Scottish Heart Health Study to investigate whether milk consumption has an independent effect on the prevalence of coronary heart disease. Milk consumption was assessed by questionnaire in men and women aged 40–59 years (n = 10359) who participated in a survey of risk factors for coronary heart disease between 1984 and 1986. Odds ratios for coronary heart disease were calculated according to volume and type of milk consumed for subjects with and without symptoms of coronary heart disease. Statistical adjustment was made for the classicial risk factors.
A higher percentage of men and women with diagnosed coronary heart disease (CHD) usually consume low-fat milk, compared with asymptomatic controls. Odds ratios for having undiagnosed heart disease did not differ significantly with volume or type of milk. However, the odds ratios for having diagnosed heart disease were lower in the moderate (0.5–1 pint/d) milk consumption group. Patterns of milk consumption in patients diagnosed as having CHD are likely to be confounded by dietary changes post-diagnosis. Milk consumption appears to have little independent effect on the prevalence of coronary heart disease in this Scottish population.  相似文献   
93.
94.
The effect of ACTH on the expression of major histocompatibility complex (MHC) class II (I-A) glycoprotein by murine peritoneal macrophages was evaluated. ACTH suppressed the expression of I-A by macrophages in a time- and dose-dependent manner. ACTH mediated its effect by decreasing the level of I-A mRNA. ACTH suppressed the expression of I-A by macrophages from mice that are susceptible to the in vivo growth of mycobacteria but did not affect the expression of I-A by macrophages from Mycobacterium bovis strain (BCG)-resistant mice. The concentrations of ACTH required to suppress I-A expression were greater than that required for an effect on adrenal steroid production and may be related to the localized production of ACTH by lymphocytes and macrophages.  相似文献   
95.
Thyroid dysfunction is a well-known contributor to psychiatric morbidity. To investigate the mechanism(s) by which thyroid hormone availability affects cerebral activity, a group of thyroidectomized individuals were studied at two points in time: when markedly hypothyroid in preparation for a thyroid cancer metastatic survey and when clinically and/or biochemically euthyroid. The analysis consisted of single photon emission computed tomography (SPECT) using a lipophilic radiopharmaceutical, technetium-99m (Tc-99m) ethyl cysteinate dimer (ECD), and measurement of mood, anxiety, and psychomotor function, at both points in time. Both increases and decreases in regional cerebral radiotracer activity were found in the hypothyroid condition relative to the euthyroid condition, and the neuropsychological assessment demonstrated significantly greater depression, anxiety, and psychomotor slowing during the hypothyroid state. Increased radiotracer activity was seen in frontal and temporal regions, posterior cingulate gyrus, thalamus, and putamen. Decreased activity was seen in the occipital cortex, and the pre- and postcentral gyri. This distribution pattern is partially consistent with findings in persons with depression and anxiety unrelated to thyroid disease, supporting the link between the symptoms observed in our subjects and their marked hypothyroidism. Finally, these results support the need to consider the effect of the thyroid state on cellular mechanisms of uptake and retention of cerebral blood flow radiopharmaceuticals when studying 'noneuthyroid' individuals.  相似文献   
96.
Postoperative intrarenal pressure measurements may be an aid to the diagnosis of acute renal transplant rejection, especially in patients treated with cyclosporine. Serial measurements of intrarenal pressure were made in 38 recipients using a fine-needle technique. Thirty-two intraoperative and 207 postoperative measurements were made, and 39 clinical rejection episodes (23 confirmed by biopsy) monitored. Intraoperative pressures in grafts with immediate function (37.4 +/- 4.0 mmHg, mean +/- SEM) were not significantly different from those with delayed function (30.9 +/- 4.8 mmHg), whereas postoperative pressures were greater (P less than 0.01) in kidneys with acute tubular necrosis (29.4 +/- 1.9 mmHg) than in functioning grafts (20.4 +/- 0.9 mmHg). Pressures recorded during clinical rejection episodes (44.3 +/- 2.3 mmHg) exceeded (P less than 0.001) those during quiescent periods (23.6 +/- 1.0 mmHg). During rejection episodes, higher pressures (P less than 0.01) were recorded from tender or palpably enlarged grafts (52.5 +/- 3.0 mmHg) than in the absence of these signs (36.3 +/- 3.1 mmHg), and patients whose transplants biopsies showed cellular rejection tended to have greater pressures (50.1 +/- 4.1 mmHg) than those with concomitant vasculopathy (36.4 +/- 3.9 mmHg), but the latter did not reach statistical significance. In 7 cases of cyclosporine toxicity the intrarenal pressure was 17.8 +/- 4.2 mmHg. Using a diagnostic cut off point of 40 mmHg, the investigation failed to recognize 26% of acute rejection episodes--and, in the presence of acute tubular necrosis, it wrongly categorized 21% of nonrejectors. While its predictive capacity was limited, the test may occasionally be helpful in the differentiation of cyclosporine toxicity and rejection in functioning kidneys.  相似文献   
97.
98.
Many physiological variables known or thought to affect erythrocyte Na+,K+-cotransport are altered in pregnancy. The interrelationships of Na+,K+-cotransport and pregnancy were therefore examined. Values were elevated by more than 30% in both second and third trimesters with a return towards non-pregnant levels in the postpartum period. Although pregnancy was also associated with elevated plasma cholesterol, renin activity and aldosterone, there was no significant relationship within the pregnant group between Na+,K+-cotransport and any of these factors. No change could be demonstrated in Na+,K+-cotransport values after 7 days of either high (greater than 250 mmol/day) or low (less than 50 mmol/day) sodium intake and values for those who developed pregnancy-associated hypertension (PAH, pre-eclampsia) were not significantly different from those in continuously normotensive women in either the second or the third trimesters of pregnancy.  相似文献   
99.
Kent bundle interruption for ventricular preexcitation has been successfully accomplished utilizing several different surgical techniques. The external closed-heart technique of Guiraudon combining surgical dissection and cryoablation has been used to interrupt 52 accessory pathways in 47 consecutive patients since May, 1985. The 35 male and 12 female patients ranged in age from 10 to 67 years (mean, 30 years). There were 25 left free wall, 13 right free wall, 13 posterior septal, and 1 anterior septal accessory pathways. Preoperative and intraoperative electrophysiological studies were performed in all patients to induce the arrhythmia and localize all accessory pathways. The operation consisted of dissection of the atrioventricular fat pad. Following this, the delta wave and retrograde accessory pathway conduction disappeared, thereby indicating successful pathway ablation. In 4 patients with right-sided accessory pathways, interruption of the pathway required cryoablation. Cryolesions (made with cryoprobe at -60 degrees C for two minutes) were created in the region of the accessory pathway insertion. All accessory pathways were successfully ablated without any deaths or heart block. Concomitant surgical procedures were performed in 4 patients. Two patients required a second operation the next day for an accessory pathway not found at the initial operation. Three patients had postpericardiotomy syndrome, and 4 had recurrent atrial fibrillation requiring therapy. The remaining patients have had no arrhythmia recurrence and have remained drug free after a follow-up of 1 month to 22 months (mean, 12.5 months). We conclude that the closed-heart technique of accessory pathway ablation is safe and reproducible, obviates the necessity for aortic cross-clamping and cardioplegic arrest, and allows instantaneous monitoring of conduction over the pathway.  相似文献   
100.
Extracapsular cataract extraction (ECCE), placement of a posterior chamber intraocular lens (PC IOL), and pars plana vitrectomy were combined in a single operation in 24 patients. Sixteen of these, 11 of whom are diabetic, have had 6 months or more of follow-up. In all cases, excellent visualization of the posterior segment was obtained, and the surgical objectives were achieved. No diabetic patient without preoperative neovascularization of the iris had this complication later. The advantages and disadvantages of alternative techniques are discussed.  相似文献   
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