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41.
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To express the core protein of HIV-1 of Chinese prevalent strain (HIV-1 (CN)) in Pichia pastoris, the fulllength gag gene was inserted into the secretory expression vector pHILS1. Linearized recombinant plasmid pHILGAG by Sail was electrotransformed into the yeast strain GS115, and the yeast transformants were identified by PCR. To induce the interest protein to be expressed, the PCR positive transformants were inoculated in the medium of BMGY and BMMY, mRNA of the strain was detected by RT-PCR, and the expressed protein was analyzed by SDS-PAGE, Western blotting and thin layer scanning. mRNA (1.3 kb) was amplified by RT-PCR. SDS-PAGE and Western blotting analysis showed that the molecular mass of the expressed protein was 55 kD, which was similar to the expected value, and the expressed protein could react with McAb to HIV-1 p24. Thin layer scanning analysis demonstrated that the whole amount of the expressed protein was approximately 13 % of the soluble protein in the supernatant. The recombinant yeast had good genetic stability. The optimal expression conditions of the engineering yeast were as follows: BMMY medium, 80-90% of dissolved oxygen, 1% methanol, and 3-day-cultivation course. Gag proteins were expressed under the optimal expression condition and purified via gel filtration chromatography. The purity of the interest protein was up to 85 %. After the purified proteins were inoculated into BALB/c mice, the anti-HIV-1 antibodies in the immunized mice could be detected by Western blotting.  相似文献   
43.
下消化道出血221例分析   总被引:2,自引:2,他引:2  
0 引言 下消化道出血是消化科的常见病 ,是指十二指肠空肠移行部 ,屈氏韧带以下的小肠和大肠疾病引起的肠道出血 .有人认为一般不包括痔和肛裂出血 [1 ] .临床最常见为慢性出血 ,但有时出血量大危及生命 ,需要做紧急处理 ,现将我院1992 - 0 1/ 1999- 0 8门诊及病房收治的 2 2 1例下消化道出血进行分析 ,报告如下 :1 临床资料 男 12 0例 ,女 10 1例 ,年龄 14~ 72 (平均 42 )岁 ,病程 16 h~ 10 a.患者分别以脓血便、暗红色血便、鲜血便或果酱色血便为主诉前来就诊 ,其中有休克症状的大出血者6例 .血 Hb<110 g·L- 1 40例 ,<80 g·L- 1…  相似文献   
44.
从头序木(AraliadasyphylaMiq)叶中分离到6个三萜化合物,用化学方法和波谱(UV,IR,MS,1HNMR,13CNMR,13CDEPT,HMQC,HMBC)分析,确定其中4种化合物的结构,分别为齐墩果酸(I),16β羟基18βH齐墩果酸(I),齐墩果酸28OβD吡喃葡萄糖甙(II)和16β羟基18βH齐墩果酸28OβD吡喃葡萄糖甙(IV)。用NOESY谱确定化合物I的立体构型。以上4个化合物均为首次从该植物中分离到,化合物IV为新化合物。  相似文献   
45.
46.
The parasympathetic nervous system is likely to be involved in migraine pathogenesis. We hypothesized that the cholinomimetic agonist carbachol would induce headache and vasodilation of cephalic and radial arteries. Carbachol (3 µg/kg) or placebo was randomly infused into 12 healthy subjects in a double-blind crossover study. Headache was scored on a verbal rating scale from 0–10. Velocity in the middle cerebral artery (VMCA) and diameter of the superficial temporal artery (STA) and radial artery (RA) were recorded. Nine participants developed headache after carbachol compared with three after placebo. The area under the curve for headache was increased after carbachol compared with placebo both during infusion (0–30 min) ( P  = 0.042) and in the postinfusion period (30–90 min) ( P  = 0.027). Carbachol infusion caused a drop in VMCA ( P  = 0.003) and an increase in STA diameter ( P  = 0.006), but no increase in the RA diameter ( P  = 0.200). In conclusion, the study demonstrated that carbachol caused headache and dilation of cephalic arteries in healthy subjects.  相似文献   
47.

Background  

Whole body vibration (WBV) exposure at work is common and studies found evidence that this exposure might cause low back pain (LBP). A recent review concluded there is a lack of evidence of effective strategies to reduce WBV exposure. Most research in this field is focussed on the technical implications, although changing behaviour towards WBV exposure might be promising as well. Therefore, we developed an intervention programme to reduce WBV exposure in a population of drivers with the emphasis on a change in behaviour of driver and employer. The hypothesis is that an effective reduction in WBV exposure, in time, will lead to a reduction in LBP as WBV exposure is a proxy for an increased risk of LBP.  相似文献   
48.
Depression in Korean immigrants with hepatitis B and related liver diseases   总被引:6,自引:0,他引:6  
The authors evaluated 50 Korean immigrants who had chronic viral hepatitis or who were healthy carriers for the hepatitis B virus in terms of the relationships between their depression scores, psychosocial stressors, social support, and biological markers of dysfunction. All participants completed a questionnaire, describing their worries and concerns, and the shortform of the Beck Depression Inventory (BDI-sf). Hepatic transaminases, albumin levels, and prothrombin times were measured during routine clinic follow-up visits and were abstracted from the medical record. Values recorded within 3 months before and within 3 months after the psychiatric interview were correlated with BDI scores. BDI-sf total scores were significantly associated with transaminase elevations (P<0.001) both before and after BDI-sf administration. BDI scores were not associated with other measures of liver dysfunction or other medical causes of depression. Patients with higher BDI-sf total scores had more psychosocial stressors (P = 0.008) and lower Global Assessment of Functioning (GAF) scores (P = 0.000).  相似文献   
49.
OBJECTIVE: To determine the cellular and matrix responses to experimental wounding of articular cartilage. METHODS: Immature and mature bovine articular cartilage was used as an in vitro model system to study the cellular responses to cartilage wounding. Explant cultures were wounded centrally with a trephine and maintained for up to 10 days. TUNEL labeling together with ultrastructural analyses were used to assess the nature of the observed cell death. In vitro labeling with 3H-thymidine was used to detect cell proliferation, and 2 antibodies (COL2-3/4M and BC-13) were used to detect changes in matrix turnover. RESULTS: Cell death was observed as a response to wounding and was considered to be a combination of necrosis and apoptosis. In immature tissue, cell death was more pronounced, particularly in the articular surface region. Within the area of cell death, many cells that did not die subsequently underwent proliferation. The collagenous network showed evidence of denaturation in the area of the wound, but "aggrecanase" activity was not detected. CONCLUSION: There are 2 contrasting, but related, responses to cartilage wounding--apoptosis and proliferation. In order to improve cartilage repair, future studies need to elucidate the regulatory mechanisms that determine these responses.  相似文献   
50.
Over 15 years, 42 children aged 2-14 years were diagnosed as having acquired aplastic anaemia. Adequate clinical details were available for 38 children who were categorised as very severe (n = 13), severe (n = 16), or nonsevere (n = 9) by the modified Camitta criteria. Treatment varied over the study period. Seven children received a bone marrow allograft from a full match family donor and three a matched unrelated donor transplant after failed treatment with antilymphocyte globulin. The remainder were treated with antilymphocyte globulin (n = 11), antilymphocyte globulin and oxymetholone (n = 4), oxymetholone with or without prednisolone (n = 12), or supportive treatment alone (n = 1). With a minimum follow up of one year since treatment, the five year survival was 70% for bone marrow transplantation with a family donor, 30% for antilymphocyte globulin, and 25% for oxymetholone. All three children with a matched unrelated donor transplant died. The prognosis of acquired aplastic anaemia remains poor for most children and new approaches to treatment are urgently required.  相似文献   
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