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21.
目的探讨骶骨H形骨折可行的治疗方法。方法运用C型臂X线机引导下经皮双侧骶髂拉力螺钉固定治疗骶骨H形骨折15例。结果15例患者均获随访,随访时间7—34个月,骨折临床愈合时间3~5个月,术后均未留下明显行走障碍,下蹲等活动接近正常。结论在C型臂X线机精确引导下,经皮双侧骶髂拉力螺钉固定技术能有效地固定骶骨H形骨折中的垂直骨折,纠正骨盆垂直方向移位,操作简洁安全,疗效可靠。  相似文献   
22.
G1、G2引物是对问号钩体具有特异性引物。分别用G1或G2单引物对问号钩体中国参考株进行前4个低严格度循环的PCR扩增,扩增带谱显示赖型、犬型、致热型、秋季型、澳洲型、临海型、乌尔夫型、溶血型为一类,而爪哇型、拜伦型、波摩那型、七日热型、巴叶赞型塔拉索夫型、曼耗Ⅱ型是不与以上赖型等血清型本为一类,双曲钩体atoc型及伊利尼细丝体伊利尼型的扩增带谱与问号钩体截然不同。应用苯酚法提取的高纯度钩体DNA  相似文献   
23.
Inactivated whole avian influenza virus (AIV) vaccine provides protection against homologous haemagglutinin (HA) subtype virus, but poor protection against a heterologous HA virus. Moreover, it induces chickens to produce antibodies to cross-reactive antigens, especially nucleoprotein, which is limits AIV serological surveillance. In this study, a recombinant fowlpox virus co-expressing HA (H5 subtype) and NA (N1 subtype) genes of AIV was evaluated for its ability to protect chickens against intramuscular challenge with a lethal dose of highly pathogenic (HP) AIV. Susceptible chickens were also vaccinated by wing-web puncture with the parent fowlpox vaccine virus. Following challenge 4 weeks later with HPAIV, all chickens vaccinated with recombinant virus were protected, while the chickens vaccinated with either the unaltered parent fowlpox vaccine virus or unvaccinated controls experienced 100% mortality following challenge. This protection was accompanied by the high levels of specific antibody to the respective components of the recombinant vaccine. The above results showed that rFPV-HA-NA could be a potential vaccine to replace current inactivated vaccines for preventing AI.  相似文献   
24.
A genome-wide screen was conducted using a large white sample to identify QTLs for FNCS geometry. We found significant linkage of FNCS parameters to 20q12 and Xq25, plus significant epistatic interactions and sex-specific QTLs influencing FNCS geometry variation. INTRODUCTION: Bone geometry, a highly heritable trait, is a critical component of bone strength that significantly determines osteoporotic fracture risk. Specifically, femoral neck cross-sectional (FNCS) geometry is significantly associated with hip fracture risk as well as genetic factors. However, genetic research in this respect is still in its infancy. MATERIALS AND METHODS: To identify the underlying genomic regions influencing FNCS variables, we performed a remarkably large-scale whole genome linkage scan involving 3998 individuals from 434 pedigrees for four FNCS geometry parameters, namely buckling ratio (BR), cross-sectional area (CSA), cortical thickness (CT), and section modulus (Z). The major statistical approach adopted is the variance component method implemented in SOLAR. RESULTS: Significant linkage evidence (threshold LOD = 3.72 after correction for tests of multiple phenotypes) was found in the regions of 20q12 and Xq25 for CT (LOD = 4.28 and 3.90, respectively). We also identified eight suggestive linkage signals (threshold LOD = 2.31 after correction for multiple tests) for the respective geometry traits. The above findings were supported by principal component linkage analysis. Of them, 20q12 was of particular interest because it was linked to multiple FNCS geometry traits and significantly interacted with five other genomic loci to influence CSA variation. The effects of 20q12 on FNCS geometry were present in both male and female subgroups. Subgroup analysis also revealed the presence of sex-specific quantitative trait loci (QTLs) for FNCS traits in the regions such as 2p14, 3q26, 7q21 and 15q21. CONCLUSIONS: Our findings laid a foundation for further replication and fine-mapping studies as well as for positional and functional candidate gene studies, aiming at eventually finding the causal genetic variants and hidden mechanisms concerning FNCS geometry variation and the associated hip fractures.  相似文献   
25.
1. We tested the ability of ouabain to cause chronic hyper tension by continuously infusing ouabain for 28 days (mini-osmotic pump implantation; i.p.). The blood pressure and metabolic effects of sham (150 mmol/L NaCI; n= 12) or ouabain infusion (10 μg/kg per day; n= 14; 100 μg/kg per day; n = 14) were examined in conscious Sprague-Dawley rats. 2. Plasma ouabain concentrations measured after 28 days of ouabain infusion were as follows: sham, not detectable (n= 11); ouabain 10 μg/kg per day, 0.60 ± 0.07 nmol/L (n= 14); and ouabain 100 μg/kg per day, 7.17 ± 0.57 nmol/L (n= 14; P < 0.001). 3. Sham or ouabain infusion did not alter food intake, bodyweight, water intake or urine output in conscious rats. 4. Blood pressure was not altered by sham treatment. Ouabain at 10 μg/kg per day or 100 μg/kg per day did not produce consistent rises in blood pressure. Ouabain at 10 μg/kg per day increased blood pressure on treatment day 12 only (+ 6mmHg; P < 0.05), while at 100μg/kg per day blood pres sure increased on treatment days 16 (+ 9 mmHg; P < 0.05) and day 18 (+ 8mmHg; P < 0.05) only. There was no significant difference in blood pressure between sham and ouabain groups. 5. Renal blood flow was decreased in rats infused with ouabain at 10 μg/kg per day (2.0 ± 0.3 mL/min per 100 g body-weight; n= 5; P < 0.01) and 100 μg/kg per day (2.2 ± 0.4 mL/ min per 100 g bodyweight; n= 7; P < 0.05) compared with sham treatment (3.5 ± 0.2 mL/min per 100 g bodyweight; n= 6). Renal vascular resistance was increased in rats treated with ouabain at 10 μg/kg per day (65.5 ± 12.6 mmHg/mL per min per 100 g bodyweight; n= 5; P < 0.01) and 100 μg/kg per day (66.0 ± 15.6 mmHg/mL per min per 100 g bodyweight; n= 7; P < 0.05) compared with sham treatment (32.6 ± 2.5 mmHg/mL per min per 100 g bodyweight; n= 6). 6. High plasma concentrations of ouabain do not cause consistent increases in blood pressure in conscious Sprague-Dawley rats.  相似文献   
26.
米非司酮作用于兔输卵管收缩活动与Ca^2+关系的研究   总被引:1,自引:0,他引:1  
通过“结合化学分离与原子吸收分光光度法”对Ca^2 含量测定和离体输卵管肌条收缩记录方法,研究米非司酮(Ru486)对增加假孕(4d)兔输卵管平滑肌收缩频率,而不改变其收缩张力和振幅时与Ca^2 之间的关系,结果提示:(1)Ru486对输卵管分泌液和组织内Ca^2 的含量分布无明显影响;(2)Ru486具有降低细胞外液高Ca^2 浓度促Ca^2 内流,而使收缩增强的效应,且能协同Ca^2 通道阻断剂(Verapamil)抑制细胞外Ca^2 内流,而致收缩减弱的效应。  相似文献   
27.
We have obtained multislice magnetic resonance (MR) images of the eye and calculated ocular dimensions along the three cardinal axes: antero-posterior (A-P), equatorial, and vertical. We found no difference in the shape of hyperopic (average refractive error: +3.72 D) and emmetropic eyes, both of which had an equatorial diameter longer than the A-P and vertical diameters. Myopic eyes (average refractive error: -6.54 D) were larger than hyperopic eyes, and most had the same spheroelliptical shape as that of the emmetropic and hyperopic eyes. The results suggest that during myopic progression an overall enlargement or a radial volume expansion has occurred.  相似文献   
28.
BACKGROUND: This study investigated the utility of the alveolar - arterial oxygen pressure difference (AaDO (2)) in predicting the short-term prognosis of acute pulmonary embolism (PE). METHODS AND RESULTS: This study retrospectively enrolled 114 consecutive patients with acute PE, diagnosed by either spiral computed tomography or high probability ventilation - perfusion lung scans. During the first 24 h of admission, all patients had initial artery blood gas collected under room air. Patient exclusion criteria were chronic lung disease, septic emboli, and moderate and low probability lung scans. Patients were assigned to 2 groups based on either 30-day death or a 30-day composite event. Receiver operating characteristic analyses was used to determine the AaDO(2) cut-off value for predicting primary and composite endpoints. Statistical analysis demonstrated significant differences in AaDO(2) between the 30-day composite endpoint group and the 30-day composite event-free survival group (p=0.012). The AaDO(2) had a strong trend between the 30-day death group and the survival group (p=0.062). The best cut-off value for AaDO(2) was 53 mmHg and using this, the positive predictive value for 30-day death was 25% and the negative predictive value was 92%. For the 30-day composite endpoint, the positive predictive value for AaDO(2) was 35%, and the negative predictive value was 84%. In this study, thrombocytopenia was also an indicator of poor prognosis for patients with acute PE. CONCLUSION: The AaDO(2) measurement is a highly useful and simple measurement for predicting short-term prognosis in patients with acute PE. It has high negative predictive value and moderate positive predictive value for 30-day death and 30-day composite event. Aggressive thrombolytic treatment strategies should be considered for patients with an initial poor prognostic parameter (ie, AaDO(2) >or=53 mmHg).  相似文献   
29.
Four selected cases of emergent IABP insertion in PV patients are presented. After angiographic documentation of critical iliac stenosis, conservative peripheral angioplasty was performed prior to IABP insertion. No patient experienced a peripheral ischemic event associated with IABP use. © 1992 Wiley-Liss, Inc.  相似文献   
30.
M Xu  B Xiong  P Cheng  Y Guo 《中国中药杂志》1992,17(4):228-30, 256
Five compounds have been isolated from the stems and leaves of Isodon albopilosus. On the basis of spectroscopic and chemical data, they were identified as macrocalyxin C, stearic acid, beta-sitosterol, ursolic acid and beta-sitosterol-beta-D-glucoside, respectively.  相似文献   
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