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71.
目的 构建大鼠MMP1 3重组腺病毒载体。方法 将MMP1 3cDNA目的片段插入腺病毒柯氏质粒中 ,再将此质粒与腺病毒DNA末端蛋白复合物共转染 2 93细胞 ,通过同源重组构建MMP1 3 重组腺病毒载体。结果 MMP1 3 重组腺病毒载体经PCR鉴定正确 ,包装纯化后 ,检测病毒滴度为 4× 1 0 9PFU/ml。结论 成功地构建了RatMMP1 3 重组腺病毒载体 ,为下一步行MMP 1 3转基因治疗低顺应性膀胱的研究提供了条件  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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The specific characteristics of genetic data lead to ethical-legal conflicts in the framework of genetic diagnosis. Several international organisations, including UNESCO and the Council of Europe, have enacted rules referring to the use of genetic information. This paper discusses possible legal and ethical criteria that could be used in genetic testing.  相似文献   
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OBJECTIVES: Dental lasers have been used for uncovering submerged implants as well as decontaminating implant surfaces when treating peri-implantitis. The objective of this study was to compare the possible alterations of the smooth surface and resorbable blast material (RBM) surface implants after using NdYAG and CO(2) lasers at various energies. MATERIALS AND METHODS: Ten smooth surface implants and 10 RBM surface implants were used. Two smooth surface implants and 2 RBM surface implants served as a control group that was not lased. The remaining implants were treated using NdYAG and CO(2) lasers. The surface of each implant was treated for 10 seconds on the second and third threads. The smooth surface implants (group 1) were treated using a pulsed contact NdYAG laser at power settings of 1, 2, 3.5, and 5 W, which are commonly used for soft tissue surgery; the corresponding energy and frequency were 50 mJ and 20 Hz, 100 mJ and 20 Hz, 350 mJ and 10 Hz, and 250 mJ and 20 Hz, respectively. The group 2 RBM implants were treated using a pulsed contact NdYAG laser. The group 3 smooth surface implants were treated using a pulsed wave non-contact CO(2) laser at 1, 2, 3.5, and 5 W, and the group 4 RBM implants were treated using a pulsed wave non-contact CO(2) laser. Data were analyzed using scanning electron microscopy. RESULTS: The control surface was very regular and smooth. After NdYAG laser treatment, the implant surface showed alterations of all the surfaces. The amount of damage was proportional to the power. A remarkable finding was the similarity of the lased areas on the smooth and RBM surfaces. CO(2) laser at power settings of 1.0 or 2.0 W did not alter the implant surface, regardless of implant type. At settings of 3.5 and 5 W, there was destruction of the micromachined groove and gas formation. CONCLUSION: This study supports that CO(2) laser treatment appears more useful than NdYAG laser treatment and CO(2) laser does not damage titanium implant surface, which should be of value when uncovering submerged implants and treating peri-implantitis.  相似文献   
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