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BACKGROUND: Peripheral blood progenitor cells (PBPCs) are commonly collected and used to reconstitute hematopoiesis after high-dose chemotherapy. However, strategies for optimal collection and assessment of leukapheresis components are not standardized. STUDY DESIGN and METHODS: Hematopoietic progenitor cell assays were performed on 369 leukapheresis components collected from 95 patients who had received doxorubicin-based chemotherapy and/or granulocyte-colony-stimulating factor (G-CSF). Precollection patient hematologic values, leukapheresis collection values, component hematopoietic progenitor cell assays, and patient outcome measures were summarized. The kinetics of mononuclear cell (MNC) and PBPC mobilization were assessed among four patient groups. RESULTS: Patient group was a significant predictor of the peripheral blood MNC count on the day of collection (p<0.0001), and that value was a significant predictor of granulocyte-macrophage– colony-forming unit (CFU-GM) yield (p<0.0001). This relationship between the peripheral blood MNC count on the day of collection and CFU- GM yield differed according to patient group (p<0.0001). CFU-GM made up a larger fraction of peripheral blood MNCs collected from patients who received chemotherapy plus G-CSF than collected from those who received G-CSF alone. Moreover, the peripheral blood MNC count and the corresponding CFU-GM yield increased significantly on consecutive days of collection in patient groups receiving chemotherapy and G-CSF but were unchanged or decreased in patients receiving G-CSF alone. CONCLUSION: The relationship between peripheral blood MNC count and leukapheresis component CFU-GM yield differed significantly between patients who received chemotherapy and G-CSF and those who received G- CSF alone for the mobilization of PBPCs. Patient peripheral blood MNC count and component CFU-GM yield are useful for both assessing and suggesting revisions to PBPC mobilization and collection strategies.  相似文献   
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OBJECTIVE: To study the influence of glycemic control and the presence of microalbuminuria on the initial response to panretinal photocoagulation (PRP) in patients with a high-risk proliferative diabetic retinopathy (PDR). RESEARCH DESIGN AND METHODS: This was a prospective cohort study with a two-by-two factorial design. We used full-scattered PRP to treat 115 eyes of type 2 diabetic patients who have high-risk PDR. HbA1c (A1C) and albumin levels in 24-h urine were constantly monitored during the pre-enrollment, treatment, and posttreatment periods. At a follow-up visit 12 weeks after the last PRP session, the fundus was examined for characteristics of regression from high-risk PDR and the response to PRP was determined to be successful or unsuccessful. The eyes were categorized into four groups based on average A1C levels and the presence or absence of microalbuminuria. The data were analyzed using a logistic regression model. Our statistical analysis determined the probability of achieving a satisfactory response to PRP in association with A1C levels and the presence or absence of microalbuminuria. RESULTS: Of the 115 eyes examined, 65 (56.5%) had a successful initial response to PRP and 50 (43.5%) did not. The probability of a satisfactory response to PRP was related to A1C levels (P < 0.05) but not to microalbuminuria and its interaction with hemoglobin glycosylation (P > or = 0.05). CONCLUSIONS: Low levels of hemoglobin glycosylation (A1C <8%) during the pretreatment, treatment, and posttreatment periods are associated with a regression of proliferative diabetic retinopathy after PRP.  相似文献   
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To determine the incidence of transfusion-associated human immunodeficiency virus (HIV) infection after routine screening of donated blood, a pilot study estimated the pretransfusion prevalence of HIV infection among blood product recipients in San Francisco. Among the 911 nonduplicate pretransfusion specimens from recipients without a clinical history of acquired immune deficiency syndrome (AIDS) or AIDS-related complex (ARC), the overall prevalence of antibody to HIV was 2.9 percent (5.2% among males and 0.6% among females; p = 0.00002). If recipients in specifically defined or possible high-risk groups (n = 348) were excluded, a seropositivity rate of 1.8 percent (10/563) was detected, with all the positives occurring in men (10/242, 4.1%) and none in women (0/321, 0%). This demonstrated prevalence of HIV infection among blood product recipients in San Francisco before transfusion was substantially higher than the known 0.02 to 0.04 percent prevalence in the donor population. Therefore, the population of women without known risk for AIDS is the best in which to assess the risk of HIV infection in patients who are currently receiving seronegative blood transfusions.  相似文献   
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目的:观察人参皂苷Rg1对急性心肌梗死后血管新生及梗死区血管内皮生长因子和缺氧诱导因子1αmRNA表达的影响及其机制。方法:实验于2005-10/2006-01在中国医科大学附属第一医院循环内科实验室完成。实验分组:健康雄性Wistar大鼠104只,体质量180~220g,随机抽签法分为假手术组8只,对照组、Rg1低剂量治疗组和Rg1高剂量治疗组各32只。实验方法:建立Wistar大鼠急性心肌梗死模型,假手术组开胸不结扎冠状动脉,3d后处死取材;对照组、Rg1低剂量治疗组和Rg1高剂量治疗组分别于术后即刻及术后每天腹腔注射生理盐水1mL、人参皂苷Rg11mg/kg和5mg/kg,术后3,7,10,14d分别取材,每组8只。实验评估:测定血清心肌酶、心肌梗死面积、梗死区微血管密度,逆转录-聚合酶链反应检测梗死区心肌组织血管内皮生长因子和缺氧诱导因子1α的mRNA表达。结果:纳入大鼠104只,均进入结果分析。①人参皂苷Rg1对大鼠心肌酶及心肌梗死面积的影响:Rg1低剂量治疗组、Rg1高剂量治疗组心肌酶较对照组明显降低[(62.25±10.79),(57.64±9.36),(78.63±11.34)μg/L;P<0.05],心肌梗死面积亦明显降低[14d:(12.15±3.68)%,(10.10±3.12)%,(13.94±3.54)%;P<0.05]。②人参皂苷Rg1对大鼠心肌梗死区微血管密度的影响:各组梗死区血管生成数量随着时间的延长呈持续增加的趋势,与对照组比较,差异有显著性意义[Rg1低剂量治疗组14d:(17.29±3.21)个/视野;Rg1高剂量治疗组14d:(23.27±3.42)个/视野;对照组14d:(9.36±3.54)个/视野;P<0.01]。③大鼠心肌梗死区血管内皮生长因子、缺氧诱导因子1αmRNA的表达:心肌梗死后血管内皮生长因子、缺氧诱导因子1αmRNA表达随缺血时间的延长有增高趋势,Rg1低剂量治疗组与Rg1高剂量治疗组明显升高,14d时血管内皮生长因子的增长出现停止或下降[Rg1低剂量治疗组14d:(1.1637±0.1786);Rg1高剂量治疗组14d:(1.7230±0.3102)];而缺氧诱导因子1α继续升高[Rg1低剂量治疗组14d:(1.7263±0.3417);Rg1高剂量治疗组14d:(2.7725±0.3219)]。结论:严重缺血可刺激心肌组织产生大量的血管内皮生长因子、缺氧诱导因子1α,人参皂苷Rg1增加其表达进而刺激心肌梗死区的血管生成,减轻缺血对心肌的损伤。  相似文献   
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目的:分离、克隆和测定中国人纤溶酶原Kringle5功能区基因,为进一步研究其功能奠定基础。方法:实验于2002—06/2003-05在广州医学院金域医学检验中心完成。①实验材料:国人胚肝组织取自广州医学院第一附属医院的流产胚胎(取得家属同意,并经广州医学院第一附属医院伦理委员会批准)。pET21a(+)载体购自Novagen公司,大肠杆菌BL21(DE3)为医学检验中心保存。引物均由上海生工合成。②实验方法:从国人胚肝组织中提取mRNA,用反转录-聚合酶链反应方法将人纤溶酶原Kringle5的cDNA扩增出来,克隆到pET21a(+)载体中测序。(D实验评估:采用紫外分光光度仪和琼脂糖凝胶电泳分析胚肝组织总RNA的抽提结果;经琼脂糖凝胶电泳鉴定Kringle5的反转录-聚合酶链反应扩增结果;pET-Kringle5重组质粒的酶切鉴定;序列测定。结果:①胚肝组织提取总RNA结果:提取的总RNA经紫外分光光度仪测得A260nm/A80nm〉1.8,A60nm,A270nm〉1.2,表明无蛋白残留;电泳结果显示提取的总RNA有明显的28S、18S两条带,说明RNA基本完整。②Kringle5的反转录-聚合酶链反应扩增结果:人Kringle5 cDNA片段长为240bp,加上引物设计的2个酶切位点,总长度为258bp,聚合酶链反应产物长度与该长度一致,符合预期结果。③)pET-Kringle5重组质粒的构建和酶切鉴定结果:用引物所带的限制性内切酶BamH Ⅰ、NdeⅠ双酶切,结果有250bp左右条带出现。④序列测定结果:证实国人纤溶酶原Kringle5功能区基因被成功克隆,序列分析证实为该基因,未发现有基因突变或多态性现象,但第153位核苷酸与文献比较存在碱基替代现象,其组成的密码子由于遗传的简并性,所编码的氨基酸相同,并未造成氨基酸组成的改变。结论:中国人纤溶酶原Kringle5功能区cDNA基因编码序列与国外文献报道的相应序列可能存在碱基替代现象。  相似文献   
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To address concerns over the prevalence of silent (antibody-negative) infections among blood donors and high-risk populations, a combination of proviral amplification by polymerase chain reaction (PCR) and viral isolation by co-culture techniques was employed to resolve the human immunodeficiency virus type 1 (HIV-1) infection status of well-characterized groups of suspect blood donors and others identified in the blood bank setting. No silent infections were found in 65 follow-up samples from 26 persistently HIV-1-seroindeterminate blood donors, 16 persistently seronegative heterosexual partners of infected transfusion recipients, and 6 high-risk seronegative homosexual men identified through donor look-back investigations. In contrast, 21 seropositive controls tested positive. These results suggest a low prevalence of persistently silent infections in at-risk populations, even in high HIV prevalence regions. The PCR assay, with a co-detected internal positive control, and appropriate confirmatory algorithms, was found to be a useful direct assay to rule out infection, especially in concert with confirmatory virus isolation.  相似文献   
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OBJECTIVES: Recent studies from several countries have shown that coeliac disease (CD) is increasingly being diagnosed in adults, as the availability of new, accurate serologic tests has made screening in the general population possible. No data exist regarding the prevalence of CD in Greece. The aim of this study was the implementation of a serologic screening procedure for CD in the adult general population of Thessaly, an area of central Greece, using a novel diagnostic algorithm. METHODS: The study included 2230 participants (1226 women, 1004 men, median age 46 years, range 18-80 years), selected by systematic random sampling, from the adult general population of Thessaly. All the serum samples were tested for total immunoglobulin A (IgA)-serum levels, to exclude IgA deficiency. Samples with total IgA within the normal range were tested for IgA antibodies against native human-tissue transglutaminase (anti-tTG); samples that were anti-tTG positive were tested for IgA antiendomysial antibodies (EmA). Samples from participants with selective IgA deficiency were examined for IgG antigliadin antibodies. Participants who were EmA-positive or antigliadin antibody-positive were referred for intestinal biopsy and human leucocyte antigen (HLA) typing. RESULTS: No participant with selective IgA deficiency was detected. Four individuals tested positive for EmA, all of whom were biopsy-proven coeliacs. Therefore, the CD prevalence in this general population sample is 1 : 558 or 1.8 per 1000 (SE 0.13). The four new patients with abnormal histology (two men, two women) were aged between 18 and 35 years. Two of them were considered to be asymptomatic and two presented with a subclinical course. All four had the heterodimer HLA-DQ2. CONCLUSIONS: This first serological screening study for CD in Greece has demonstrated that CD prevalence in Thessaly is among the lowest reported in Europe.  相似文献   
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