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31.
目的 通过病例对照研究 ,了解中国老年人群血管内皮型一氧化氮合酶 (eNOS)基因目的 通过病例对照研究 ,了解中国老年人群血管内皮型一氧化氮合酶 (eNOS)基因Glu2 98Asp多态性的分布 ,分别探讨其与老年脑梗死及血脂以及一氧化氮等脑梗死危险因素的关系。 方法对门诊及住院中确诊的 4 0例老年脑梗死和 16 9例性别、年龄相匹配的老人 ,测量他们的身高、体重及座位血压 ,并测定他们的空腹血脂、空腹血糖 (FBS)及一氧化氮 (NO)等 ,应用聚合酶链反应 (PCR)和限制性片断长度多态性 (RFLP)检测eNOS基因Glu2 98Asp多态性。结果 脑梗死和对照组eNOS基因Glu2 98Asp多态性构成有显著性差异 (χ2 =4 31,P =0 0 38) ,脑梗死组Glu/Asp基因型高于对照组(32 5 %vs 17 8% ) ;脑梗死组 2 98Asp等位基因频率高于对照组 (16 2 5 %vs 8 9% ) ,但是两组等位基因频率的分布比较 ,没有显著性差异 (χ2 =3 81,P =0 0 5 1)。结论 eNOS基因Glu2 98Asp多态性在中国老年人群中存在 ,并且基因...  相似文献   
32.
High cord blood immunoglobulin E (cbIgE) is known to be associated with increased risks of atopic diseases in childhood. The relationship between genetic polymorphisms and high cbIgE has not been well documented. A cross-sectional study was conducted to assess the association between cbIgE and genetic polymorphisms of interleukin (IL)-4 -590C/T, the beta-subunit of the high-affinity receptor for IgE (FcepsilonRI-beta) E237G, lymphotoxin (LT)-alphaNcoI alleles, and tumor necrosis factor (TNF)-alpha -308G/A. A total of 320 mother-neonate pairs were recruited from four maternity hospitals from different locations of Taiwan. Cord blood was obtained and assayed for cbIgE. Polymerase chain reaction followed by restriction fragment length polymorphism was used to assess the genotypes. Three hundred pairs of mothers and neonates were included in the final analysis. Infants with IL-4 -590 C allele were found to have higher risk of elevated cbIgE (> or =0.35 IU/ml, 24.3%) (p = 0.004). After adjusting for gender, birth order, maternal age, and history of allergic disease in maternal and paternal families, odds ratios for CC and CT genotypes were 4.41 and 3.16 (95% confidence interval 0.78-22.67, and 1.66-6.13), respectively, using TT genotype as reference. The genotypes of FcepsilonRI-beta, LT-alpha, and TNF-alpha were not associated with cbIgE before or after the adjustment. Our finding suggested a significant association of cbIgE with genetic polymorphism of IL-4 -590C/T, but not with the genotypes of FcepsilonRI-beta, LT-alpha, and TNF-alpha.  相似文献   
33.
Abstract –  In the treatment of crown fractures, adhesive fragment reattachment provides a good alternative to other restorative techniques, offering several advantages. The present paper reports a case in which the treatment of a cervical crown fracture was accomplished by reattaching the tooth fragment with a flowable resin composite. Orthodontic root extrusion was performed with a modified Hawley appliance prior to fragment reattachment. The clinical and radiographic results after 2.5 years were successful.  相似文献   
34.
The current study was performed to understand the relationship between graft length placed within the bone tunnel and intraosseous graft healing in anterior cruciate ligament (ACL) reconstruction. Twenty-four adult beagle dogs were divided into two groups of 12 animals each. In each animal, ACL reconstruction using a 4-mm diameter autogenous flexor tendon graft was done in the left knee. In groups I and II, the graft having a length of 15 and 5 mm, respectively, was placed within the tibial tunnel. The proximal end of the graft was placed through the over-the-top route in all animals. In each group, five animals were sacrificed immediately after surgery, and the remaining seven were sacrificed at 6 weeks postoperatively. Biomechanical and histologic evaluations were performed. In pull out testing, the ultimate failure load and the linear stiffness of the graft-tibia complex harvested at 6 weeks were significantly greater than those harvested at the time-zero period. There were no significant differences in those parameters between groups I and II at 6 weeks. In each group, the perpendicular collagen fibers connecting the tendon to the bone tunnel wall were observed only in the narrow area located close to the intra-articular tunnel outlet. In conclusion, excessively long placement of the flexor graft within the bone tunnel does not result in an additional increase of anchoring strength and stiffness of the graft in ACL reconstruction.  相似文献   
35.
36.
用薄层聚丙烯酰胺凝胶电泳方法分析118头人繁殖恒河猴血清四种蛋白质和同工酶遗传基因位点的多态性,结果表明,除醇脱氢酶(ADH)为单态外,其余三个基因位点均表现多态,前清蛋白(PA)可分为AA、AB、AC、AD和BB、CC,EE七种表型,各基因的频率为A 0.85,B 0.072,C 0.042,D 0.009,E 0.034转铁蛋白(Tf)可分为CC、DD、EE、FFGG、CD、CE、CG、CH、DE、DF、DG、DH、EF、EG、EH、FG十七种表型,墓因频率为C 0.064,D 0.380,E 0.188,F 0.111,G 0.244,H 0.014,苹果酸脱氢酶(MDH)可分MDH)1-1和MDH2-1两种表型,基因频率为MDH~10.958和MDH~20.042。  相似文献   
37.
A computer-assisted method for the registration of food intakes in real time according to a concise and simple procedure was subjected to a series of controls in order to assess precision. The method employs the 'portion' of a composite dish as unit of measure. The constancy of the portion was tested. The results show that the recipes of the diet of a subject may be stored and utilized in deferred time without loss of precision: data to be recorded in real time are then very limited. The length of period of analysis was also studied. The time of investigation should not be shorter than two weeks to obtain precise information on the feeding habits of an individual subject, whereas for a group of subjects the diary of a single day provides information of sufficient precision.  相似文献   
38.
PROBLEM: There is substantial data that support the efficacy of paternal leukocyte immunization (PLI) for the treatment of alloimmune mediated miscarriage; however, there is confusion regarding the laboratory test that should be performed to determine levels of maternal anti-paternal leukocyte antibodies (MAPLA). METHOD: Popular methodologies employed include: 1) microcytotoxicity (MCX), 2) mixed lymphocyte culture (MLC), and 3) cell flow cytometry crossmatch (FCXM). Cell flow cytometry crossmatch correlates well with the more difficult MLC assay although the former proves the more sensitive study. This work compares the MCX assays with FCXM. The study group consisted of ten women who had a history of three or more spontaneous abortions (SABs). All ten had very low levels (<10%) of MAPLA as measured by FCXM. Following PLI all subjects demonstrated elevated levels (>50%) of MAPLA by FCXM. At 12 weeks gestation, sera were simultaneously measured for MAPLA by MCX and FCXM. RESULTS: Although all ten patients had very high levels of MAPLA by FCXM during pregnancy, five of ten had antibodies to HLA Class I and two of ten had antibodies to HLA Class II paternal antigens by MCX. Furthermore, all patients who were positive by MCX to paternal Class I antigens were also positive to Class I antigens not seen in either parent. Both patients who were positive by MCX to paternal Class II antigens were also positive to maternal Class II antigens. Notable is that all ten women eventually delivered healthy infants. CONCLUSION: Based on this preliminary study, the MCX assay is neither sensitive or reliable enough to determine the need and/or to monitor the effectiveness of PLI. Flow cytometry should be the modality of choice when determining the need for alloimmunotherapy and to monitor the effectiveness of treatment.  相似文献   
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40.
1. Aldosterone levels in patients with unilateral aldosterone-producing adenomas may be responsive or unresponsive to the renin-angiotensin system, with the former often previously misdiagnosed as bilateral adrenal hyperplasia. 2. In tumours from patients in the responsive subgroup, renin mRNA is expressed in greater amounts than in tumours from patients in the unresponsive subgroup, or in normal adrenals. 3. We compared the frequency of four renin gene polymorphisms in peripheral blood DNA from the two subgroups and found significant associations between BglI, TaqI and HinfI restriction fragment length polymorphisms (RFLP) and aldosterone responsiveness. 4. Allelic variation in the constitutive renin gene was associated with a specific cause of hypertension.  相似文献   
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