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The spin-spin relaxation time, T2, of skimmilk, sodium caseinate dispersions and milk ultrafiltrate was measured as a function of pH and temperature using pulse proton NMR. The T2 shows a maximum around pH = 5.2 for skimmilk, decreases with decreasing pH for sodium caseinate dispersions and is independent of pH for milk ultrafiltrate. For all systems studied T2 increases with temperature, but, the extent of increase depends on the system. It is concluded that the T2 of casein dispersions is mainly determined by factors determining the state of aggregation of the caseins. Apart from affecting the extent of aggregation of the casein particles, micellar calcium phosphate probably contributes also directly to the measured T2.  相似文献   
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OBJECTIVE: To assess the outcome after transthoracic endoscopic sympathectomy (TES) for upper limb hyperhidrosis. DESIGN: Prospective cohort study. SETTING: District general hospital. SUBJECTS: Consecutive patients undergoing TES for upper limb hyperhidrosis over a fifteen month period. INTERVENTIONS: One-stage bilateral TES. MAIN OUTCOME MEASURES: Change in quality of life as shown by the Short Form-36 health assessment questionnaire. RESULTS: Sixteen patients (11 women and 5 men, median age 26 years) underwent operation without complications. At median follow-up of 6.2 months, symptomatic improvement was found in 26 of 32 limbs treated (82%). Truncal compensatory hyperhidrosis was reported by 13 patients but was severe in only three. There were significant improvements in social function (p = 0.01) and mental health (p = 0.025) as assessed by the SF-36. CONCLUSION: Despite a high incidence of compensatory hyperhidrosis, TES improved both the symptoms and overall quality of life in patients with upper limb hyperhidrosis.  相似文献   
145.
We report the case of a 57-yr-old woman presenting with moderate weight loss, abdominal distension, and lymphedema of the legs and vulva. Computed tomography of the abdomen revealed massive thickening of the rectal wall, mesentery, and retroperitoneum. Primary amyloidosis was diagnosed by immunohistochemistry from the rectum and duodenum. To our knowledge, lymphedema due to primary amyloidosis has not yet been reported. The diagnosis should be presumed in the case of retroperitoneal thickening and lymphedema and can be established by immunohistochemistry.  相似文献   
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AIMS: We explored the role of microcirculation integrity following the chronic occlusion of an infarct-related artery to assess the behaviour of collateral circulation during and after reperfusion by coronary angioplasty METHODS AND RESULTS: Eighteen patients with a proximally occluded left anterior descending artery and firm evidence of intercoronary collateral circulation were studied with selective coronary angiography and selective intracoronary myocardial contrast echocardiography, before coronary angioplasty, and at 5 and 15 min and 12 h later. Myocardial enhancement during myocardial contrast echocardiography was evaluated with a semiquantitative score (0-3), which was correlated to basal and 6 months' regional left ventricular wall motion results. 16/18 procedures were successfully performed; four patients with an inadequate acoustic window were excluded. Restenosis was evident at the 6 months' follow-up in two patients. Basal myocardial contrast echocardiography indicated that 81/192 segments from the left anterior descending coronary artery and 90/192 from the right coronary artery were perfused; no perfusion was observed in 21 segments either before or after coronary angioplasty. After coronary angioplasty, the angiographic intercoronary collateral circulation immediately disappeared, and myocardial contrast echocardiography revealed that there was a progressive reduction of segments perfused by the right coronary artery and an increase in segments perfused by the left anterior descending coronary artery. Regional left ventricular wall motion analysis demonstrated that there was abnormal motion in 51/192 segments. There was no improvement in segments with score 0 and abnormal motion after 6 months (100% sensitivity), but 16/17 segments with score 3 did show an improvement (98% specificity). The predictive value of intermediate scores (1-2) in detecting long-term improvement, was only 43%. CONCLUSION: These data show that the adaptive mechanism observed in the behaviour of epicardial and microvascular circulation after reperfusion of a chronic occluded infarct-related artery can vary. In addition, this study clearly shows that microvascular integrity detected by myocardial contrast echocardiography can provide myocardial viability.  相似文献   
149.
Dopamine receptor-coupled stimulation of inositol phosphate formation has been characterized extensively, but little is known about the diacylglycerol arm of this dual-signaling pathway. This study examined several parameters of cytidine diphosphate-diacylglycerol (CDP-DG) accumulation as an index of agonist-stimulated DG formation. Rat brain slices pre-labeled with 5-[3H]cytidine were incubated with various test agents in the presence of LiCl and accumulated CDP-DG analyzed. Dopamine and SKF38393 significantly and dose-dependently stimulated CDP-DG accumulation. SKF38393 responses were inhibited by neomycin and reversed by myo-inositol or by exclusion of LiCl. Compared to inositol phosphate formation in 2-[3H]inositol-prelabeled slices, the CDP-DG responses were proportionately greater, while the agonist EC50 values were similar between the two assays. The D1-receptor antagonist SCH23390 inhibited SKF38393-mediated responses at 0.1-10 microM concentrations, whereas greater concentrations reversed the inhibition. SKF38393 effects were completely blocked by the DG kinase inhibitor R59022, thus precluding any role for phospholipase-D or de novo phosphatidate synthesis in the dopaminergic response. D609 which inhibits phosphatidylcholine-specific phospholipase-C (PLC), potently inhibited both CDP-DG accumulation and inositol phosphate formation. These findings demonstrate that the selective D1-receptor antagonist SCH23390 is a partial agonist at the D1-like dopamine receptor that couples to phosphoinositide signaling, that dopaminergic facilitation of phosphoinositide signaling is independent of de novo phosphatidate synthesis, and that the widely used enzyme inhibitor, D-609, is probably not selective for phosphatidylcholine-specific PLC in brain slice preparations. The greater sensitivity of the CDP-DG measurement presents this assay as a reliable and possibly superior index of dopamine receptor-coupled PLC activation in intact tissues.  相似文献   
150.
Food intake and body weight are determined by a complex interaction of regulatory pathways. To elucidate the contribution of the endogenous peptide cholecystokinin, mice lacking functional cholecystokinin-A receptors were generated by targeted gene disruption. To explore the role of the cholecystokinin-A receptor in mediating satiety, food intake of cholecystokinin-A receptor-/- mice was compared with the corresponding intakes of wild-type animals and mice lacking the other known cholecystokinin receptor subtype, cholecystokinin-B/gastrin. Intraperitoneal administration of cholecystokinin failed to decrease food intake in mice lacking cholecystokinin-A receptors. In contrast, cholecystokinin diminished food intake by up to 90% in wild-type and cholecystokinin-B/gastrin receptor-/- mice. Together, these findings indicate that cholecystokinin-induced inhibition of food intake is mediated by the cholecystokinin-A receptor. To explore the long-term consequences of either cholecystokinin-A or cholecystokinin-B/gastrin receptor absence, body weight as a function of age was compared between freely fed wild-type and mutant animals. Both cholecystokinin-A and cholecystokinin-B/gastrin receptor-/- mice maintained normal body weight well into adult life. In addition, each of the two receptor-/- strains had normal pancreatic morphology and were normoglycemic. Our results suggest that although cholecystokinin plays a role in the short-term inhibition of food intake, this pathway is not essential for the long-term maintenance of body weight.  相似文献   
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