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941.
A cytopathic measles virus was isolated from a brain biopsy of a subacute sclerosing panencephalitis (SSPE) patient. The agent could be transferred to Vero cells by cocultivation, but the infectivity always remained cell-associated -ie, a defective virus infection. The cell-associated nature of the virus was retained through 25 passages in Vero cells. Intracerebral inoculation of hamsters (2-6 days old) with the cocultured Vero cells gave rise to 100% mortality in 5-7 days. The virus retained its cell-associated nature after passage in hamsters. Electron microscopy of the brain and Vero cocultures showed the presence of virus-like ribonucleoparticles mainly in the nucleus. The presence of viral antigens in the nucleus, cytoplasm, and on the plasma membranes was confirmed by immunofluorescence. Using a combination of immunological and biochemical techniques, it was shown that all the viral proteins were synthesized with the exception of the haemagglutinin. Inclusion of the fusion inhibitor SV4814 (CBZ-D phenylalanine-L-phenylalanine-L-arginine-NO2) in the culture medium led to the elimination of the SSPE infection.  相似文献   
942.
Summary In 23 patients with rheumatoid arthritis the plasma protein binding of3H-imipramine and the plasma levels of 13 proteins were measured in order to examine the significance of the proteins for the binding of imipramine. The degree of3H-imipramine binding did not differ significantly from that in healthy controls. It was positively correlated with the concentrations of fibrinogen, 1-acid-glycoprotein, ceruloplasmin, complement C3c, haptoglobin and hemopexin. Erythrocyte sedimentation rate was also highly positively correlated with binding. The concentration of several of the proteins showed a significant covariation. The3H-imipramine binding was negatively correlated with the concentration of albumin and the latter was negatively correlated with some of the proteins mentioned-above. No correlation with the levels of apolipoproteins A and B was found. There appears to be more a qualitative than a quantitative change in3H-imipramine binding in patients with rheumatoid arthritis.  相似文献   
943.
The postanesthetic respiratory depression with sevoflurane, isoflurane and halothane was studied in twenty-one patients. They were divided into three groups of seven patients each. One group underwent sevoflurane anesthesia, another group isoflurane and the third group halothane. Following extubation, the decrease in blood concentration of the anesthetic agent was most rapid with sevoflurane and slowest with halothane. Twenty minutes following extubation, resting ventilation and ventilatory response to carbon dioxide returned to the preanesthetic state with sevoflurane and isoflurane anesthesia. With halothane anesthesia, however, the depressive respiratory effects of halothane remained; depressed ventilatory response to carbon dioxide, decreased tidal volume and increased respiratory frequency. Although halothane has been reported to have the least depressive respiratory effect of the three, its elimination was slowest. Thus the respiratory effects of halothane persisted up to and past the twenty minute mark, far longer than with sevoflurane or isoflurane.(Doi M, Ideda K: Postanesthetic respiratory depression in humans: A comparison of sevoflurane, isoflurane and halothane. J Anesth 1: 137–142, 1987)  相似文献   
944.
A seroepidemiological study was performed on HTLV-III, T. pallidum, C. trachomatis and Hepatitis B virus (HBV), in Butare, Rwanda, among 33 female prostitutes, 25 male customers of prostitutes, and 60 male and female controls. As compared with female controls the prostitutes had a higher prevalence of antibodies to HTLV-III (29/33 versus 4/33, p<0.001), T. pallidunz (TPHA: 27/33 versus 6/33, p<0.001; RPR: 19/33 versus 233, p<0.001; FTA-Abs: 27/33 versus 5/33, p<0:001) and C. trachomatis (IgG IF: 31/33 versus 13/33, p<0.001). HBV serological markers were more often detected in the prostitutes than in the female controls (31/33 versus 18/33, p<0.001) although HBs antigen carriage rate was similar in both groups. As compared with male controls, the male customers of prostitutes had more frequently detectable antibodies to HTLV-III (7/25 versus 2/27, p = 0.05), and a positive RPR (10/25 versus 1/27, p<0.01). Among the 118 individuals studied, odds ratios and trend analysis disclosed a significant association between HTLV-III seropositivity and a positive TPHA, RPR, FTA-Abs, Chlamvdia IgG IF test and serological markers to HBV. No association was found between HTLV-III seropositivity and IIBs Ag carriage. This study suggests that HTLV-III has to be considered as an infectious agent transmitted among promiscuous Central African heterosexuals by sexual contact and/or parenteral contact with unsterile needles used for STD treatments.  相似文献   
945.
Summary Patients with malignant disease may be predisposed to bacterial infections because of neoplastic disruption of normal tissue barriers, exogenous immunosuppressive therapy (drugs with or without radiation), and intrinsic host immune deficits secondary to these diseases. Diminished polymorphonuclear leukocyte numbers or function and impaired humoral immunity are highly correlated with the development of serious bacterial infections. The usual signs and symptoms of infection may be absent or altered in a compromised host.Therapy must be instituted promptly upon clinical suspicion of bacterial infection, and empirical choices should usually include combinations that are synergistic for likely pathogens based on knowledge of the local predominant flora and susceptibility data. Synergism has most often been demonstrated in combinations that utilize a -lactam (semisynthetic penicillin or cephalosporin) and an aminoglycoside. Triple drug therapy has not been shown to be advantageous. Monotherapy with third generation cephalosporins, carbapenems, monobactams, or ureidopenicillins has not been proven to offer advantages over 2-drug regimens for these patients.Patients with blood deficient in granulocytes (granulocytopenic) who respond to 2-drug therapy but remain deficient in neutrophils (neutropenic) may need continued treatment until the neutropenia subsides. Those who do not respond and remain febrile with an unclear focus of infection may need to be started on antifungal therapy in addition to the antibacterial agent. The use of oral agents for the prophylaxis of neutropenic patients against bacteremia remains controversial. If drugs are used, co-trimoxazole and nystatin suspension may be preferable.  相似文献   
946.
The volume/pressure (V/P) curve of the total respiratory system in paralysed patients is drawn assuming that volume changes of the respiratory system (V resp) equals volume displacement of the measuring apparatus (V syr), usually a supersyringe. However, in 93 VP curves we found that O2 removed from the lung-syringe system during the procedure (proportional to the time) largely exceedes the CO2 added to the lung-syringe system (V gas). This results in a net loss of volume from the system (V resp相似文献   
947.
报告经血清免疫学抗HAVIgM、抗-HBcIgM、HBV-DNA、HBsAg/IgM复合物以及乙肝三种抗原抗体系统检测48例重型肝炎中甲、乙型肝炎病毒感染情况。结果:31例为HBV感染,1例为HAV感染,1例未定型,15例(31.25%)为甲、乙型合并感染(混合感染7例、重叠感染8例)。15例中亚急性10例、慢性5例;死亡或恶化10例,与同期“单纯”感染的重肝比较,包括主要临床生化指标均无显著差异。有7例患者病程中有近期出现“急黄肝”症状的历史,随后病情突然加重;1例发生在住院期间,且血清抗-HAVIgM转阳,最后死亡。认为合并感染可使部分急、慢性肝炎病情加重,甚至发展成重型。应注意发现。  相似文献   
948.
Summary The contamination of autologous marrow with clonogenic tumor cells has been the main argument against ABMT in acute leukemia.In a preclinical study we evaluated an active cyclophosphamide derivative named ASTA Z 7557. We observed that the toxic effect of this drug on CFU-GM growth was dependent on nucleated cell concentration as well as on red blood cell contamination. The potency of the drug was in close relationship with the incubation temperature.The growth of leukemic CFU was inhibited with an ASTA Z dose higher than 30 g/ml. In our system, beyond 40 g/ml more than 95% of committed stem cells are destroyed.Fifteen patients had autotransplant because of AML for 10 patients and because of ALL for 5 patients (4 patients were grafted in relapse and 11 patients in remission).We demonstrated that the marrow take was possible although the inoculum is CFU-GM depleted.Five of the 10 AML patients are alive and remain disease-free at 45 +, 65 +, 190 +, 345+ and 570 + days from ABMT without any maintenance treatment. Four of the 5 ALL patients are alive, three of them in complete remission (404+, 110+, 250+ days).The number of patients reported in this clinical study was relatively small and more cases should be evaluated to be conclusive. Nevertheless the feasibility of chemopurified ABMT was demonstrated.  相似文献   
949.
徐颖华  徐苗  叶强 《实用预防医学》2022,29(8):1015-1019
在过去几十年,随着疫苗的广泛使用,不同国家和区域引起流行性脑脊髓膜炎(简称流脑)病原体的血清群也发生了变迁。本文将脑膜炎球菌疫苗免疫接种、感染人群、不同区域和国家流脑的流行趋势及其内在机制研究进展进行综述,为进一步了解流脑流行趋势变化与其疫苗接种和后续制定免疫策略提供参考。  相似文献   
950.
目的 了解长沙地区无偿献血人群隐匿性乙型肝炎病毒感染(occult hepatitis B virus infection,OBI)流行情况,探讨HBV基因型分布特征和S区氨基酸突变的情况。方法 对长沙地区检测结果为HBsAg-/HBV DNA+的无偿献血血液样本进行HBV血清标志物检测,对其中的OBI样本进行HBV病毒载量检测和S区基因扩增,分析血清学标志物抗HBs与病毒载量检出与否的关系,并对扩增产物进行HBV基因分型和突变位点分析。结果 2019年1月—2020年1月长沙地区173 893份无偿献血标本共确认58例OBI样本,OBI流行率为0.033%;共发现7种血清学模式,抗HBc单独阳性最多,占38.98%,所有样本中抗HBc阳性率为89.83%;16例样本能检测出病毒载量,其中14例样本浓度小于100 IU/ml;抗HBs阳性组和阴性组间的病毒载量检出率无统计学差异;75.0%(12/16)样本扩增出S区序列,基因型均为B型,均发生突变,其中11例的HBsAg抗原决定簇及周边主要亲水区域(major hydrophilic region, MHR)发生氨基酸突变。结论 长沙地区无偿献血者中的OBI感染率在全国属于偏低水平;HBV基因型主要是B型,MHR区的氨基酸突变可能是造成OBI的原因,突变有本地特点。  相似文献   
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