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Sexuality and Disability -  相似文献   
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Previous studies from this Laboratory have revealed few significant age-related changes in either hepatic microsomal cytochrome P450 content or NADPH-cytochrome P450 reductase activity, prompting the suggestion that the nearly ubiquitous age-associated decline in the hepatic metabolism of xenobiotics by the mixed-function oxidases is a result of alterations in the lipid matrix in which the macromolecular components are organized. In order to examine this postulate, the membrane microenvironment surrounding hepatic microsomal cytochrome P450 was enzymatically digested with snake venom phospholipase A2, and the kinetics of conversion of cytochrome P450 to cytochrome P420 determined for preparations obtained from rats of varying age. There were no significant differences in the kinetics of conversion of cytochrome P450 to cytochrome P420, suggesting that there are no significant age-related changes in the lipid microenvironment immediately adjacent to cytochrome P450. However, there was a slight difference, independent of age, in the rate of conversion of cytochrome P450 to cytochrome P420 between smooth and rough microsomes. The results are discussed in terms of general experimental approaches toward understanding drug metabolism in senescent organisms.  相似文献   
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The beStent is a new stainless steel, balloon-expandable mesh stent which has a unique serpentine design. Rotation of the unique low stress junctions upon expansion leads to orthogonal locking of the wires, maximizing radial strength and assuring zero shortening. The stent has delineating gold markers which assure precise positioning. We aim to present the initial acute results in a pilot registry for stent evaluation. Two hundred eighty-four stents were used in a total of 217 patients (age 57.9 ± 3.10 years; 178 males; 39 females) in seven centers, for variable indications. Stents of 15-, 25-, and 35-mm length were used. The arteries treated were the left anterior descending (n = 112, 42%), circumflex (n = 54, 20.2%), right coronary (n = 95, 35.5%), left main (n = 1, 0.4%), and vein graft (n = 5, 1.9%). Lesion types were: A in 42 patients (16.5%); B1 in 53 patients (20.7%); B2 in 81 patients (31.8%); and C in 79 patients (31%). One hundred fifty-nine patients required one stent, 40 patients required two stents, and 18 patients required three or more stents. Anticoagulation protocol included procedural heparin with aspirin with/without ticlopidine. Smooth angiographie results were obtained in all cases with no plaque herniation. Acute angiographic success was obtained in 97% of the patients, and acute clinical success in 95% of the patients. Complications within 30 days were: 3 deaths (1.4%) (2 noncardiac); 2 (0.9%) myocardial infarctions; and 2 (0.9%) stent thromboses. Therefore, the beStent is useful in treatment of complex lesions of variable length and complexity, providing excellent acute results with a low complication rate, in spite of unfavorable basic clinical and angiographie characteristics.  相似文献   
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In animals, perfluorochemicals (PFCs) are effective ultrasound (US) contrast agents that produce hepatic, splenic, and tumor enhancement. The use of Fluosol-DA 20%, an emulsion of perfluorodecalin and perfluorotripropylamine, was studied in nine non-critically ill patients with cancer who had liver lesions. US studies without Fluosol were compared with studies obtained 24, 48, and 72 hours after Fluosol infusion. Vital signs and extensive laboratory analyses are performed before and after Fluosol infusion. Liver metastases from colonic, pancreatic, and gastric carcinoma exhibited rim or diffuse enhancement after a Fluosol dose of 1.6 g/kg or greater. Fluosol produced echogenic enhancement of the liver and spleen relative to kidney at a dose of 2.4 g/kg, allowing the detection of nonenhancing lesions. In addition, Fluosol at a dose of 1.6 g/kg or greater allowed detection of lesions not seen before contrast medium was administered in three of the seven patients studied. There was a mild increase in the level of serum glutamic oxaloacetic transaminase in two patients, one given 2.4 and the other 3.2 g/kg of Fluosol. Mild and transient allergic reactions without change in vital signs were experienced by two patients.  相似文献   
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Many findings implicating prefrontal cortical and limbic areas of the brain and endocrine systems in the neuropathology and pathophysiology of bipolar illness have greatly increased our understanding of the neurobiology of the illness. New imaging techniques such as PET, MRI, SPECT, and MRS have detailed more evidence of specific regional alterations in the brains of bipolar patients than was thought possible just 20 years ago. These methods are beginning to be used to help predict response to treatment. Examining the mechanisms of action of mood stabilizers (such as lithium, carbamazepine, and valproate) has provided clues to potential underlying neurobiological abnormalities in the illness. Recent studies of postmortem brain tissue have begun to confirm prefrontal cortical and limbic neurochemical and microstructural alterations in patients with bipolar illness compared with controls. It is postulated that it is the balance between primary pathological versus secondary adaptive alterations in gene expression in the illness and their enhancement or dampening by pharmacotherapy, that may determine the episodic course of mood fluctuations and remissions. Further examination of the pathophysiology and neurobiology of bipolar illness should lead to both more effective treatments and, potentially, secondary and even primary episode prevention.  相似文献   
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Perhaps the most significant link in achieving the nation's immunization objectives is the extent of parental knowledge. Admittedly, this is a weak link. The 1990 federal objectives calling for an official format using common guidelines for completion of immunizations, though well-conceived, has not been used exclusively by health care givers. The lack of accord has permitted the proliferation of many different immunization records that are not only confusing to parents, but also to health care providers at times. A standard national immunization record could be an essential element in strengthening the weak link of parental knowledge of immunizations and stressing the importance of preserving such a record for a lifetime.  相似文献   
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