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21.
北京农村居民健康状况及卫生服务需求调查 总被引:17,自引:5,他引:12
目的了解北京农村居民健康状况及卫生服务需求特点。方法从昌平区、顺义区、大兴区、房山区随机抽取25~64岁农民1605人进行统一问卷调查。结果农民高血压自报患病率为22.4%,超重和肥胖率为56.1%;现在吸烟率为34.4%,缺乏运动率为41.6%;家庭主要经济支出为学生上学(35.3%),建房(25.4%)和疾病(21.2%);54.9%家庭医疗费用支出占总收入的10%以上;最关心的健康问题主要是慢性疾病防治(70.2%);最希望获得的健康知识是慢性病预防知识(72%);希望获得健康知识的途径是广播和电视(81%);家庭最希望获得的医疗保健服务是方便看病和获得药物(73.8%)。结论慢性病给农民带来沉重负担,并成为农民关心的主要健康问题。 相似文献
22.
Recapitulation of fast skeletal muscle development in zebrafish by transgenic expression of GFP under the mylz2 promoter. 总被引:1,自引:0,他引:1
Bensheng Ju Shang Wei Chong Jiangyan He Xukun Wang Yanfei Xu Haiyan Wan Yan Tong Tie Yan Vladimir Korzh Zhiyuan Gong 《Developmental dynamics》2003,227(1):14-26
A 1,934-bp muscle-specific promoter from the zebrafish mylz2 gene was isolated and characterized by transgenic analysis. By using a series of 5' promoter deletions linked to the green fluorescent protein (gfp) reporter gene, transient transgenic analysis indicated that the strength of promoter activity appeared to correlate to the number of muscle cis-elements in the promoter and that a minimal -77-bp region was sufficient for a relatively strong promoter activity in muscle cells. Stable transgenic lines were obtained from several mylz2-gfp constructs. GFP expression in the 1,934-bp promoter transgenic lines mimicked well the expression pattern of endogenous mylz2 mRNA in both somitic muscle and nonsomitic muscles, including fin, eye, jaw, and gill muscles. An identical pattern of GFP expression, although at a much lower level, was observed from a transgenic line with a shorter 871-bp promoter. Our observation indicates that there is no distinct cis-element for activation of mylz2 in different skeletal muscles. Furthermore, RNA encoding a dominant negative form of cAMP-dependent protein kinase A was injected into mylz2-gfp transgenic embryos and GFP expression was significantly reduced due to an expanded slow muscle development at the expense of GFP-expressing fast muscle. The mylz2-gfp transgene was also transferred into two zebrafish mutants, spadetail and chordino, and several novel phenotypes in muscle development in these mutants were discovered. 相似文献
23.
24.
W K Chong M Paley I D Wilkinson M A Hall-Craggs B Sweeney M J Harrison R F Miller B E Kendall 《AJNR. American journal of neuroradiology》1994,15(1):21
PURPOSETo document differences in the cerebral proton MR spectra of patients with early and late stages of human immunodeficiency virus (HIV) infection.METHODWe studied the relative N-acetyl-aspartate (NAA) levels by localized proton spectroscopy of the parietooccipital region of the brain in 43 HIV-seropositive patients, including 26 with an acquired immunodeficiency syndrome (AIDS)-defining diagnosis, and in eight control subjects.RESULTSReduced relative NAA levels were shown in those HIV-1-seropositive patients: 1) with AIDS against HIV-1-seropositive patients without AIDS (P < .04); 2) with HIV-1-associated cognitive/motor complex against neurologically healthy patients (P < .007); 3) with encephalopathic changes on MR against those with normal imaging (P < .001); and 4) on follow-up against their results on initial study (P < .03).CONCLUSIONSBy clinical (Centers for Disease Control classification) and radiologic (MR evidence of white-matter disease) criteria indicating late-stage HIV infection, reduced relative levels of NAA have been demonstrated. Spectroscopic abnormalities can be quantitatively tracked with time. This paper demonstrates the clinical use of detecting NAA as a putative in vivo measure of the neuronal loss that has been demonstrated in postmortem studies of patients with AIDS. This neuronal loss, which is believed to underlie the HIV-1-associated cognitive/motor complex, is thought to be attributable directly or indirectly to the presence of HIV in the brain. Proton spectroscopy may serve as a quantitative noninvasive indicator of this aspect of cerebral involvement in HIV disease. 相似文献
25.
Henryk J Salacinski Nigel R Tai Robert J Carson Alan Edwards George Hamilton Alexander M Seifalian 《Journal of biomedical materials research》2002,59(2):207-218
Poly(ester)urethane and poly(ether)urethane vascular grafts fail in vivo because of hydrolytic and oxidative degradative mechanisms. Studies have shown that poly(carbonate)urethanes have enhanced resistance. There is still a need for a viable, nonrigid, small-diameter, synthetic vascular graft. In this study, we sought to confirm this by exposing a novel formulation of compliant poly(carbonate-urea)urethane (CPU) manufactured by an innovative process, resulting in a stress-free. Small-diameter prosthesis, and a conventional poly(ether)urethane Pulse-Tec graft known to readily undergo oxidation in a variety of degradative solutions, and we assessed them for the development of oxidative and hydrolytic degradation, changes in elastic properties, and chemical stability. To simulate the in vivo environment, we used buffered solutions of phospholipase A(2) and cholesterol esterase; solutions of H(2)O(2)/CoCl(2), t-butyl peroxide/CoCl(2) (t-but/CoCl(2)), and glutathione/t-butyl peroxide/CoCl(2) (Glut/t-but/CoCl(2)); and plasma fractions I-IV, which were derived from fresh human plasma centrifuged in poly(ethylene glycol). To act as a negative control, both graft types were incubated in distilled water. Samples of both graft types (100 mm with a 5.0-mm inner diameter) were incubated in these solutions at 37 degrees C for 70 days before environmental scanning electron microscopy, radial tensile strength and quality control, gel permeation chromatography, and in vitro compliance assessments were performed. Oxidative degradation was ascertained from significant changes in molecular weight with respect to a control on all Pulse-Tec grafts treated with t-but/CoCl(2), Glut/t-but/CoCl(2), and plasma fractions I-III. Pulse-Tec grafts exposed to the H(2)O(2)/CoCl(2) mixture had significantly greater compliance than controls incubated in distilled water (p < 0.001 at 50 mmHg). No changes in molecular weight with respect to the control were observed for the CPU samples; only those immersed in t-but/CoCl(2) and Glut/t-but/CoCl(2) showed an 11% increase in molecular weight to 108,000. Only CPU grafts treated with the Glut/t-but/CoCl(2) mixture exhibited significantly greater compliance (p < 0.05 at 50 mmHg). Overall, results from this study indicate that CPU presents a far greater chemical stability than poly(ether)-urethane grafts do. 相似文献
26.
27.
Arthroscopic all-inside repair techniques of lateral meniscus anterior horn tear: a technical note 总被引:1,自引:0,他引:1
Choon Key Lee Jeung Tak Suh Chong Il Yoo Hyung Lae Cho 《Knee surgery, sports traumatology, arthroscopy》2007,15(11):1335-1339
Although the conventional outside-in technique is especially useful for repairing tears in the anterior portion of the meniscus,
it has a disadvantage of making an additional 1–2 cm sized skin incision and tying knots subcutaneously over the capsule.
Therefore we devised two all-inside repair techniques of lateral meniscus anterior horn tear according to the site of meniscal
tear, meniscosynovial junction or red–red zone. Because these techniques are modified methods of the outside-in meniscal repair
using a spinal needle, they are as simple as conventional outside-in technique. In addition they have advantages of vertical
mattress suture, which is an important characteristic of the all-inside repair, and no additional incision. We recommend these
techniques as an alternative method for repairing an anterior horn tear of the lateral meniscus. 相似文献
28.
29.
Choriocarcinoma is the most malignant tumor of gestational trophoblastic neoplasia. It grows rapidly and metastasizes to
the lung, liver, and, less frequently, to the brain. Renal involvement is rare. Magnetic resonance imaging (MRI) is a useful
modality to image the affected tissues; it contributes to the evaluation and management of the disease. One case of renal
choriocarcinoma with MRI evaluation is reported.
Received: 24 February 1997/Accepted: 14 April 1997 相似文献
30.
Islet amyloid polypeptide (IAPP) has been recently identified as the principal constituent of amyloid deposits in pancreatic islets of patients with type 2 (non-insulin-dependent) diabetes mellitus and causes insulin resistance in some target cells. In addition, glucose-induced insulin secretion is inhibited by IAPP. We studied the effect of IAPP on proinsulin biosynthesis in rat insulinoma (RINr) cells. Glucose at concentrations of 0, 15, 30, 60, 100, and 300 mg/dl stimulated proinsulin biosynthesis in a dose-responsive and and actino-mycin D-inhibitable manner after 6 h of incubation. At a glucose concentration of 300 mg/dl, IAPP decreased the mean responses of proinsulin biosynthesis to 61.2 and 29% at concentrations of 0.1 and 1 microM, respectively, compared with the IAPP-free control. In conclusion, IAPP inhibits glucose-induced proinsulin biosynthesis in RINr cells. IAPP might play an important role in the pathogenesis of type 2 diabetes mellitus. 相似文献