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The concentration of microsomal cytochromes P-450, and of protein in the homogenate, cytosol and microsomes were measured in the liver, kidney and duodenal mucosa of healthy well-fed male and female camels, sheep and goats. For comparison, data from the liver of male and female rats were also obtained. The protein concentrations in the tissues of adult animals were broadly similar in the four species. The concentration of cytochromes P-450 was highest in the liver, followed by the kidney, then the duodenal mucosa in all the species. No cytochromes P-450 were detected in the tissues of immature (less than 1 mo) male goats, whereas the female goat had the highest concentrations of these enzymes in the liver and kidney when compared with the respective tissues in the other species studied. Males had higher activity of cytochromes P-450 than females in the three tissues, except in the duodenal mucosa of sheep, where males had lower activity than females. In camel liver and sheep kidney, the amount of cytochromes P-450 were similar in the two sexes. The present results suggest that the mature female goat is the species best equipped to handle xenobiotics which are detoxified by the cytochromes P-450 and other drug metabolizing enzymes in diseased or malnourished animals is suggested as these two conditions are known to modify drug metabolizing enzymes.  相似文献   
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The treatment of deep cartilage defects in load-bearing joints is a problem that still has no satisfactory solution. Full-thickness defects of the articular cartilage rarely heal spontaneously, usually leaving damage that can lead to early arthrosis. Techniques currently available for the treatment of chondral defects include abrasion, drilling, micro-fracturing, transplantation of tissue autografts and allografts, and cell transplantation. Osteochondral autograft transplantation is currently the only surgical cartilage repair technique known to lead to the formation of genuine hyaline articular cartilage and its retention at least in the medium term. The Draenert method, in which a water-cooled diamond bone-cutting system is used, is an effective procedure for resurfacing the joints affected by localised cartilaginous defects, even when there is also severe bone loss. Donor-side morbidity can be kept to a minimum by filling the defect caused by harvesting with a press-fit cylinder of cancellous bone covered with periosteum for protection.  相似文献   
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Ischemic injury plays an important role in chronic renal transplant failure (CRTF). Down-regulation of ecto-adenosine triphosphatase (ATPase) in combination with up-regulation of ecto-5'-nucleotidase is a hallmark of ischemic injury. We studied the expression of renal ecto-5'-nucleotidase and ecto-ATPase in experimental renal transplantation. Fisher 344-to-Lewis allografted rats were either treated with an angiotensin-converting enzyme inhibitor (ACEi) or left untreated. Lewis-to-Lewis syngrafted rats served as controls. Untreated allografted rats developed proteinuria, glomerulosclerosis, and mild intimal hyperplasia. ACEi completely prevented focal and segmental glomerulosclerosis (FGS) and proteinuria, but significantly enhanced intimal hyperplasia. Untreated allografted rats revealed marked vascular ecto-5'-nucleotidase activity, which increased with ACEi. Vascular ecto-5'-nucleotidase activity was absent in syngrafted animals. Ecto-5'-nucleotidase activity correlated well with intimal hyperplasia. Glomerular ecto-ATPase expression was significantly reduced in untreated allografted rats compared to syngrafted rats and correlated well with the extent of FGS. ACEi prevented reduction in glomerular ecto-ATPase. We found de-novo expression of ecto-5'-nucleotidase at sites of renal intimal hyperplasia. Glomerular ecto-ATPase expression was markedly reduced in allografted rats and was prevented by ACEi. These enzyme expression patterns suggest local ischemic damage in experimental CRTF.  相似文献   
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Contemporary discourse contains numerous examples of use of the concept of culture by social and behavioral scientists. Simple reification, where the speaker makes culture into a thing capable of action exemplifies one usage in public discourse. Some quantitative social scientists attempt to characterize people’s cultural identities by means of a single categorical variable, which often “lumps” people into categories such as “Hispanic” or “Black” that in fact have numerous culturally bounded subcategories. Approaches that emphasize cultural process are preferable to those who attempt to categorize; more complex measures of acculturation help investigators to make convincing analyses of circumstances in which health disparities occur. Examples in which investigators make appropriate use of cultural characterizations demonstrate their utility in investigating health disparities in Haitian American women, injecting and noninjecting drug users, Hispanic youth, and adult Hispanics at risk of HIV infection. Focus on culture in the study of health disparities can identify entanglements between structural factors such as poverty and lack of education and cultural factors such as beliefs about health. Qualitative methods coupled with quantitative methods have great potential to improve investigators’ grasp of cultural nuance while capturing the distribution of qualitatively derived behaviors.  相似文献   
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BACKGROUND CONTEXT: Osteoporosis is a major cause of morbidity in worldwide elderly populations. Patients may become susceptible to vertebral compression fractures (VCFs) from low-impact situations. For patients who have failed conventional, palliative medical therapy, kyphoplasty not only reduces pain associated with vertebral fractures, but also offers a minimally invasive procedure with the potential to address fracture reduction and spinal sagittal alignment. Kyphoplasty involves expanding an inflatable balloon tamp to create a cavity within a vertebral body before cement deposition. PURPOSE: To evaluate the safety and efficacy of kyphoplasty to reduce and fix painful osteoporotic VCFs. STUDY DESIGN/SETTING: A retrospective, single-arm cohort study of consecutive kyphoplasty patients treated at a single center. PATIENT SAMPLE: Three hundred sixty VCFs were treated during 254 kyphoplasty procedures on 222 osteoporotic patients (mean age, 76 years [range, 28-98]; 28% male and 72% female). OUTCOME MEASURES: Patient-reported pain ratings were examined. Cement extravasation was monitored by intraoperative fluoroscopy and on postoperative radiographs. Anterior and midline vertebral height were assessed from standing, lateral radiographs obtained preoperatively and postoperatively. The number of patients who returned with symptomatic, new fractures was monitored. Perioperative complications were recorded. Mean follow-up occurred 21 months after kyphoplasty (range, 6 months through 36 months). RESULTS: Immediate pain relief was reported by 89% of patients by the first follow-up visit. One patient experienced postoperative pain as a result of radiculopathy related to bone filler leakage into the foramen. The remaining patients had persistent pain and were diagnosed with either a new fracture or underlying degenerative disc disease. Greater than or equal to 20% restoration of lost vertebral height (anterior) was observed in 63% of fractures with an overall mean restoration of 30%, and > or = 20% restoration of lost vertebral height (midline) was detected in 69% of fractures with an overall mean restoration of 50%. In this cohort, 12% (30/254) of the patients required additional kyphoplasty procedures to treat 36 symptomatic, new adjacent and remote fractures. No device-related complications occurred. CONCLUSIONS: Kyphoplasty is a safe and effective, minimally invasive procedure for relief of pain associated with VCF. In our series we also demonstrated some restoration of vertebral height and partial correction of sagittal alignment.  相似文献   
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