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21.
An OUR-QGD gamma ray stereotactic body radiotherapy system (body knife), made in China, is described. According to its structure and the principle of gamma radiation revolved on a focus, the energy distribution of scattered radiation in its treatment room is calculated. The structural shielding of the wall, roof, and door for a certain treatment room is calculated according to the local radiation protection law.  相似文献   
22.
妊娠期糖尿病62例临床分析   总被引:1,自引:0,他引:1  
目的 探讨妊娠期糖尿病的合理处理及预后.方法 选择62例妊娠期糖尿病患者进行回顾性分析.结果 妊娠期糖尿病62例,其中单纯饮食控制17例,饮食控制 胰岛素治疗43例,2例未治疗.剖宫产42例,阴道产20例.合并妊高症3例,羊水过多2例,羊水过少4例,羊水栓塞1例,早产5例,高胆红素血症3例,真性红细胞增多症2例,死胎2例,新生儿窒息4例,新生儿畸形1例.结论 对妊娠合并糖尿病的孕妇进行早期的诊断及治疗,选择合适的时间及方式终止妊娠可以减少母儿并发症的发生率.  相似文献   
23.
BMP-2 gene polymorphisms and osteoporosis: the Rotterdam Study.   总被引:7,自引:0,他引:7  
After reported associations of variations in the BMP-2 gene with osteoporosis in small populations, we studied the association of the BMP-2 gene polymorphisms Ser37Ala and Arg190Ser with osteoporosis in 6353 men and women from the Rotterdam Study. We did not observe an association of these variants with BMD, bone loss, hip structural analysis parameters, and fracture risk. INTRODUCTION: Bone morphogenetic protein 2 (BMP-2) plays a role in osteoblast differentiation. BMP-2 gene variation has previously been associated with osteoporosis in various small populations, but current evidence remains inconclusive about the exact association with osteoporosis. Therefore, we studied the association of two polymorphisms located in the BMP-2 gene (Ser37Ala and Arg190Ser) and haplotypes defined by these polymorphisms with BMD, rates of bone loss, parameters of hip structural analysis (HSA), and fractures in the Rotterdam Study, a large prospective cohort study of diseases in the elderly. MATERIALS AND METHODS: Databases were searched for polymorphisms and haplotype blocks in the BMP-2 gene region. Allele frequencies for Ser37Ala and Arg190Ser were determined in 60 blacks and 110 Chinese from Coriell panels. Genotype data on Ser37Ala and Arg190Ser were available for 6353 individuals from the Rotterdam Study population. Haplotype alleles defined by Ser37Ala and Arg190Ser were inferred using PHASE software. Genotype and haplotype analyses for BMD (measured at the lumbar spine and femoral neck), bone loss per year (measured at the femoral neck), and HSA were performed using AN(C)OVA. Fractures were analyzed using a Cox proportional-hazards model and logistic regression. All outcomes were adjusted for age, height, and weight. RESULTS: Allele frequencies were 2.5% for Ala37 and 40.2% for Ser190, whereas haplotype allele frequencies were 57.28% (Ser37Arg190), 40.19% (Ser37Ser190), 2.50% (Ala37Arg190), and 0.02% (Ala37Ser190). For BMD, bone loss, HSA outcomes, and (incident) fractures, no differences could be seen between genotype and haplotype groups. Conclusions: In this large population-based cohort of Dutch whites, we conclude that the BMP-2 Ser37Ala and Arg190Ser polymorphisms or haplotypes thereof are not associated with parameters of osteoporosis.  相似文献   
24.
跻身红尘     
一袭蓑衣,一根鱼竿,临岸静坐。庄子参破世间万物.宁愿静守一泓静水.坐看风云变幻. 一垄田.一把犁.茅屋菊花。陶渊明脱离浊淖,采菊东篱得见南山.行于世俗之外。  相似文献   
25.
26.
The objective of this study is to assess the efficacy and safety of herbal medicines (HMs), as a monotherapy or adjunct therapy, compared to placebo or conventional approaches in the treatment of idiopathic Parkinson's disease (PD). We conducted a systematic review of randomized controlled trials from both conventional and alternative medicine sources. Outcome measures were overall improvement, quality of life, reduction of levodopa dose, and adverse events. Nine studies were included, each testing a different HM. Six of the trials had limited internal validity due to major flaws in design, including the lack of proper randomization; insufficient blinding; unclear inclusive criteria in terms of diagnostic criteria, baseline staging, and duration of disease; lack of proper sample size calculation; and insufficient data analysis. Imbalances in gender and ethnicity among the patients in the included trials were observed. No major adverse events emerged, and no specific pattern was detected from the trials describing such data. In addition to major methodological defects, heterogeneity in (1) HM tested, (2) control treatment, and (3) outcome measure hindered in-depth data analysis and synthesis. Current evidence is insufficient to evaluate the efficacy and safety of various HMs. Further studies with improved trial design and reporting, with assessment on cost-effectiveness, quality of life, and qualitative data are warranted.  相似文献   
27.
Legionella pneumophila is a common cause of sporadic community-acquired pneumonia, but culture-proven legionellosis is rarely diagnosed. There is no laboratory test for Legionnaires' disease that can detect all patients with the disease. Culture is the standard diagnostic method and should be initiated as soon as possible in suspected cases. We describe a rare case of community-acquired pneumonia caused by L. pneumophila serogroup 6. A 77-year-old man was admitted to a tertiary care hospital because of high fever, productive cough, and progressive dyspnea. Chest radiography showed bilateral pneumonia, which led to respiratory failure necessitating mechanical ventilatory support. Despite antibiotic therapy, his condition continued to deteriorate and acute renal failure also developed. Urine was negative for L. pneumophila. Culture of the sputum yielded L. pneumophila serogroup 6, although there was no elevation of the serum antibody titer. Pneumonia resolved gradually and he was extubated after treatment with levofloxacin followed by erythromycin. L. pneumophila other than serogroup 1 should be included in the differential diagnosis of patients with suspected atypical community-acquired pneumonia.  相似文献   
28.
29.
2 121例老年急性冠脉综合征患者血清脂类浓度的分析   总被引:1,自引:0,他引:1  
目的分析60岁以上老年人血清脂类水平的参考值,并探讨急性冠脉综合征与血脂指标的相关性.方法将3 766例健康成人分为≤60岁和>60岁的两个年龄段,采用生物化学的方法测量他们的血脂水平,找出60岁以上老年人的脂类参考值.同时分析2 121例老年急性冠脉综合征病人的脂类指标.结果 60岁以上老年人血脂参考值为:TC 4.65±1.96×1.05mmol/L;TG 1.02±1.96×0.45mmol/L;HDL-C 1.47±1.96×0.40mmol/L;LDL-C 2.98±1.96×0.56mmol/L;ApoA1 1.32±1.96×0.25g/L;ApoB 0.99±1.96×0.35g/L,并且急性心肌梗死和不稳定性心绞痛病人血清脂类各项指标之间没有显著性差异.结论血清LDL-C/HDL-C>5和TG ≥1.9mmol/L这两项联合指标比其他单独指标与老年人急性冠脉综合征关系更密切.  相似文献   
30.
Coronary flow reserve (CFR) has been used toassess coronary microcirculation and epicardial coro-nary stenoses[1— 3 ] . CFR is defined as the ratio ofcoronary flow under maximal coronary vasodilatationto coronary flow under resting conditions[4 ] .Whenthe cross- sectional area of epicardial coronary arteriesis constant,coronary flow velocity (CFV) ratios areequal to volume flow ratios.The most common method used clinically formeasuring CFVR is intracoronary Doppler flow(ICD) analysis re…  相似文献   
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