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101.
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   
102.
目的探讨肥胖患者下腹部手术采用Joel—Cohen切口对预防非感染性切口裂开的临床效果。方法选择切口部位皮下脂肪层厚达4—5cm的妇产科手术患者90例,随机分为观察组44例,采用Joel—Cohen切口;对照组46例,采用下腹正中直切口。观察切口愈合和脂肪液化情况。结果观察组切口甲级愈合率显著高于对照组(P〈0.01);脂肪液化切口裂开率显著低于对照组(P〈0.05)。结论脂肪组织厚达4—5cm以上下腹部手术切口,采用Joel—Cohen切口可以减少脂肪液化,切口愈合显著优于下腹直切口,值得临床推广应用。  相似文献   
103.
Microvascular thrombosis is a prominent feature in cardiac delayed xenograft rejection (DXR). We investigated the impact of warfarin or low-molecular-weight heparin (LMWH) anti-coagulation on xenograft function using a heterotopic pig-to-primate model. Donor hearts were from CD46 transgenic pigs and baboon immunosuppression included tacrolimus, sirolimus, anti-CD20 and TPC, an alpha-galactosyl-polyethylene glycol conjugate. Three groups of animals were studied. Group 1 (n = 9) was treated with warfarin, Group 2 (n = 13) with LMWH and Group 3, received no anti-coagulant drugs. The median duration of xenograft function was 20 days (range 3-62 days), 18 days (range 5-109 days) and 15 days (range 4-53 days) in Groups 1 to 3 respectively. Anti-coagulation achieved the targeted international normalized prothrombin ratio (INR) and anti-factor Xa levels consistent with effective in vivo therapy yet, no significant impact on median xenograft function was observed. At rejection, a similar histology of thrombosis and ischemia was apparent in each group and the levels of fibrin deposition and platelet thrombi in rejected tissue was the same. Anti-coagulation with warfarin or LMWH did not have a significant impact on the onset of DXR and microvascular thrombosis. However, a role for specific anti-coagulant strategies to achieve long-term xenograft function cannot be excluded.  相似文献   
104.
105.
[目的]揭示青少年胸椎特发性侧凸患者椎管内脊髓的偏移,明确其变化趋势,并探讨其可能的发生机制和临床意义。[方法]本研究包括39名以右胸弯为主弯的青少年特发性脊柱侧凸(adolescent idiopathic scoliosis,AIS)患者。测量主胸弯节段内(T5-12)椎管内脊髓与凸凹侧椎弓根之间的距离,计算脊髓的偏移,揭示其变化趋势,并分析顶椎区脊髓偏移与主胸弯Cobb's角和顶椎相对偏移之间的相关性。[结果]在T5-12节段椎管内,脊髓与凸侧椎弓根之间的距离显著大于与凹侧椎弓根之间的距离(P〈0.05),即脊髓向凹侧椎弓根偏移,且以顶椎区最为显著,而逐渐向两侧端椎区递减。顶椎区脊髓偏移与主胸弯Cobb’s角和顶椎相对偏移存在显著的正相关(相关系数分别为0.631和0.546)。[结论]胸椎特发性脊柱侧凸患者存在侧凸节段椎管内脊髓偏移的现象,且以顶椎区最显著。研究结果提示脊髓偏移可能与脊椎偏移后凹侧脊神经的牵拉有关,而且凹侧置钉的风险高于凸侧。  相似文献   
106.
107.
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   
108.
The nuclear content, area and perimeter of the nucleus of lymphocytes in the C.S.F. were determined quantitatively by means of image analysis technique. 26 cases of central nervous system lymphocytic leukemia (CNLL), and 8 suspected cases were studied, other 56 cases who did not have leukemic and neoplastic diseases and had normal C.S.F. lymphocytes were taken as a control. Our data showed that all the mean nuclear content (MNC), mean nuclear area (MNA), mean nuclear perimeter (MNP), and the maximum and minimum nuclear contents of the 2 groups of former patients were obviously higher than those of the contral (P less than 0.01). These results presented suggestion that the image analysis technique can be used for differentiating the leukemic lymphocyte from normal one especially in suspected cases, and thus the diagnosis of CNLL might be improved.  相似文献   
109.
110.
We previously reported that lymphatic mapping using isosulfan blue can be used to identify sentinel nodes (SNs). This study was undertaken to evaluate the feasibility of using the SN technique in treating early gastric cancer and to explore its usefulness for minimal invasive surgery. Twenty-three patients with early gastric cancer who underwent SN biopsy were retrospectively evaluated. Based on SN evaluation, individualized surgery was performed in five patients with T1N0M0 gastric cancer. When pathological examination of frozen sections revealed metastasis in SNs, we performed a standard D2 gastrectomy. Laparoscopic local resection was applied when the SN biopsy was negative. Our results showed that the success rate with SN biopsy in early gastric cancer was 100%, as were the accuracy, sensitivity, and specificity. All five patients with early gastric cancer had SNs negative for metastases both by frozen section and by postoperative pathology. Thus, all these patients underwent laparoscopic local resection without extended lymphadenectomy. We conclude that SN biopsy is a useful tool to individualize the operative procedure, and laparoscopic local resection can be safely performed using SN guidance in selected patients with early gastric cancer.  相似文献   
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