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61.
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背景与目的:阻塞性睡眠呼吸暂停低通气综合征(OSAHS)患者罹患心血管疾病的危险性增加。内皮细胞损伤被认为是动脉硬化的始动机制之一。本研究观察了OSAHS患者循环中凋亡的内皮细胞与血管收缩功能异常的关系。方法:研究对象包括14例确诊OSAHS患者和10例健康对照。在基线以及持续气道内正压(CPAP)治疗8周后测定臂动脉血流介导扩张(反映内皮依赖臂动脉扩张的指标)。采用流式细胞术测量循环中凋亡的内皮细胞。结果:  相似文献   
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BACKGROUND: Insulin-like growth factor I (IGF-I), like growth hormone (GH), is excreted in urine in a smaller fraction than the concentration found in blood. Exercising subjects undergo post-exercise proteinuria. The present work aims to propose a method for urinary IGF-I analysis (uIGF-I) by defining urinary concentration in sedentary individuals and athletes before and after strenuous exercise. METHODS: Urine samples were collected from 30 sedentary healthy male individuals during the morning and from 30 well-trained cyclists, before and after a competition of about 3 h (150 km). uIGF-I was measured in undiluted acidified urine by radioimmunoassay (RIA) method using a purified polyclonal rabbit antibody, human 125I-IGF-I and a second anti-rabbit antiserum. The acidification of the urine samples and the excess of IGF-II addition in the incubation medium of the assay were used to dissociate the binding and to block the interference from IGF binding proteins (IGFBPs). Urinary growth hormone (uGH), total protein (utPr) and creatinine (ucr) concentrations were also measured by immunoradiometric assay (IRMA), colorimetric and capillary electrophoresis methods, respectively. RESULTS: The analysis range was 0-2500 ng/l (0-327 pmol/l), the intra- and inter-assay coefficients of variations (CVs) ranged from 2.3% to 7.8%, respectively. The detection limit was 0.6 pg/tube. The uIGF-I/creatinine (cr) ratio in healthy subjects was 70 +/- 8 pg/mg cr. The uIGF-I/creatinine ratio (pg/mg cr) was different (p<0.001) in athletes before vs. after competition 93 +/- 27 vs. 136 +/- 13. Athletes' [uIGF-I/total proteins] ratio (ng/mg tPr) before and post-exercise was 2.3 +/- 0.5 and 2.5 +/- 0.3, respectively. CONCLUSIONS: uIGF-I assay appears to be an effective way of monitoring IGF-I excretion. In the cyclists, in the pre-exercise state, uIGF-I was comparable with that measured in sedentary healthy individuals. In the cyclists, after strenuous exercise, the increased uIGF-I/cr and uGH/cr ratios suggested a relation with the post-exercise proteinuria. In conclusion, proteinuria physiologically obtained, such as post-exercise proteinuria, might be a new approach in IGF-I system investigation.  相似文献   
65.
AIM: Angiogenesis correlates with disease progression in various haematological malignancies. This study investigated the association between microvascular density (MVD) and the Ki-67 proliferation index (Ki-67 PI), bone marrow infiltration, and C reactive protein (CRP) in patients with multiple myeloma. METHODS: Bone marrow MVD was examined in 44 biopsies at diagnosis and 15 in plateau phase by immunostaining the endothelial cells with a monoclonal antibody to CD34. The Ki-67 PI was evaluated by a double immunostaining technique using the monoclonal antibodies MIB-1 and CD38. RESULTS: MVD, Ki-67 PI, bone marrow infiltration, and CRP were significantly higher in pretreatment patients than in controls and decreased in patients achieving plateau phase. MVD significantly correlated with Ki-67 PI and infiltration, and Ki-67 correlated with infiltration. CONCLUSION: In multiple myeloma, apart from being a marker of proliferative activity, Ki-67 is also associated with bone marrow angiogenesis and tumour burden.  相似文献   
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This trial tests the hypothesis that confirming a clinical diagnosis of familial hypercholesterolemia (FH) by finding a genetic mutation reduces patients' perceptions of control over the disease and adherence to risk-reducing behaviors. Three hundred forty-one families, comprising 341 hypercholesterolemia probands and 128 adult relatives, were randomized to one of two groups: (a) routine clinical diagnosis; (b) routine clinical diagnosis plus genetic testing (mutation searching in probands and direct gene testing in relatives). The main outcome measures were perceptions of control over hypercholesterolemia, adherence to cholesterol-lowering medication, diet, physical activity, and smoking. There was no support for the main hypothesis: finding a mutation had no impact on perceived control or adherence to risk-reducing behavior (all P-values > 0.10). While all groups believed that lowering cholesterol was an effective way of reducing the risk of a heart attack, participants in whom a mutation was found believed less strongly in the efficacy of diet in reducing their cholesterol level (P = 0.02 at 6 months) and showed a trend in believing more strongly in the efficacy of cholesterol-lowering medication (P = 0.06 at 6 months). In conclusion, finding a mutation to confirm a clinical diagnosis of FH in a previously aware population does not reduce perceptions of control or adherence to risk-reducing behaviors. The pattern of findings leads to the new hypothesis that genetic testing does not affect the extent to which people feel they have control over a condition, but does affect their perceptions of how control is most effectively achieved. Further work is needed to determine whether similar results will be obtained in populations with little previous awareness of their risks.  相似文献   
68.
Intestinal ischemia as the first manifestation of vasculitis   总被引:3,自引:0,他引:3  
OBJECTIVE: To summarize current knowledge regarding the diagnosis and management of gastrointestinal vasculitis. METHODS: Three cases of gastrointestinal vasculitis with acute abdominal ischemia as their first manifestation are presented. Underlying diseases were microscopic polyangiitis, systemic lupus erythematosus (SLE), and polyarteritis nodosa (PAN). Relevant English-language articles collected from the PubMed database were reviewed. RESULTS: Among the angiitides, PAN, SLE, and Henoch-Sch?nlein are those most commonly accompanied by gastrointestinal complications. Intestinal vasculitis usually occurs when there is evidence of generalized disease activity. Abdominal computerized tomography is a valuable tool for diagnosing intestinal ischemia and suspected vasculitis. CONCLUSIONS: In young patients presenting with intestinal ischemia, it is essential to assess the possibility of an underlying systemic disease. With prompt initiation of immunosuppressive treatment, surgery may be avoided. Prognosis is improved when there is minimal delay in surgical intervention.  相似文献   
69.
Effect of radiation and contrast media on chromosomes. Preliminary report   总被引:1,自引:0,他引:1  
Adams  FH; Norman  A; Mello  RS; Bass  D 《Radiology》1977,124(3):823
  相似文献   
70.
Post-transfusion purpura: a heterogeneous syndrome   总被引:3,自引:0,他引:3  
Zeigler  Z; Murphy  S; Gardner  FH 《Blood》1975,45(4):529-536
Three new patients with post-transfusion purpura (PTP) are described. As the manifestations in two differ significantly from those of previously reported cases, they serve to expand the definition of this syndrome. Although all 14 previously reported cases have occurred in Pl- A1-negative females, one of our patients was a Pl-A-negative male. Moreover, a female whose postrecovery platelets possessed the Pl-A1 antigen is described. Antiplatelet antibody activity was detected in all three patients by the 51Cr release test; in contrast, only one reacted in the complement (C) fixation assay. Serum obtained during the acute episode from the PlA1-positive patient reacted against platelets from four of 11 normals by C fixation and against platelets from 48 of 53 normals by 51Cr release, including five of nine Pl-A1-negative platelet samples. This case represents the first instance of PTP in which the platelet isoantibody was not specifically directed against the Pl-A1 antigen. These observations suggest that PTP may be a more heterogeneous disorder than previously realized.  相似文献   
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