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941.
Summary Two Iranian patients with chronic progressive spastic paraparesis and urinary dysfunction were referred to our hospital with the presumptive diagnosis of multiple sclerosis (MS). Routine CSF analysis and magnetic resonance imaging of the two patients were only partially characteristic of MS. Testing for antibodies to human T-cell leukemia virus type I [HTLV-1] in serum using a radioimmune precipitation assay revealed antibodies to HTLV-I in both patients. The infection with HTLV-I was confirmed by polymerase chain reaction (PCR) and liquid hybridization analysis using primers to the tax/rex region and a corresponding probe, demonstrating proviral DNA in peripheral blood mononuclear cells of both patients. On the basis of these findings demonstrating the presence of proviral HTLV-1 DNA in the two Iranian patients, the initial diagnosis of MS was corrected to that of HTLV-I-associated myelopathy (HAM). In contrast, several patients with definite MS (nine from Germany, two from Iran) with a relapsing and remitting form of the disease were tested for HTLV-1 infection by enzyme-linked immunosorbent assay and PCR, which yielded negative results. However, the mother of one HAM patient was found to be infected with HTLV-I. To support an association between HTLV-I infection and CNS disease in the two HAM patients, we analyzed the production of specific IgG antibodies within the CNS based on a simple enzyme immunoassay for viral IgG antibodies in CSF and serum. In the two HAM patients there was significant intrathecal antibody production directed against HTLV-I, but this was not found in any of the samples from MS patients. These findings demonstrate an immune reaction to HTLV-I in the CNS of HAM patients, thus confirming the association of infection and CNS disease. The demonstration of intrathecal HTLV-I antibody production also proved useful for the differential diagnosis of MS or HAM, especially in patients from areas endemic for HTLV-I.Abbreviations DTPA diethylenetriaminepentaacetic acid - ELISA enzyme-linked immunosorbent assay - HAM HTLV-I-associated myelopathy - HTLV-I human T-cell leukemia virus type I - MRI magnetic resonance imaging - MS multiple sclerosis - PBMC peripheral blood mononuclear cells - PCR polymerase chain reaction - RIPA radioimmune precipitation assay - SDS sodium dodecyl sulfate - TSP tropical spastic paraparesis  相似文献   
942.
Psyllium is a hydrophilic agent found in many bulk laxative preparations. We report the occurrence of an anaphylactic reaction in a patient after ingestion of a psyllium-containing laxative. IgE mediation of the reaction was suggested by a positive immediate skin test to psyllium, positive passive transfer skin test, lack of skin response during passive transfer with heat treated serum, and an elevated IgE (RAST) to psyllium seed.  相似文献   
943.
Human immunodeficiency virus (HIV-1) enters target cells by binding its gp120 exterior envelope glycoprotein to CD4 and one of the chemokine receptors, CCR5 or CXCR4. CD4-induced (CD4i) antibodies bind gp120 more efficiently after CD4 binding and block the interaction with the chemokine receptor. Examples of CD4i antibodies are limited, and the prototypes of the CD4i antibodies exhibit only weak neutralizing activity against primary, clinical HIV-1 isolates. Here we report the identification of a novel antibody, E51, that exhibits CD4-induced binding to gp120 and neutralizes primary HIV-1 more efficiently than the prototypic CD4i antibodies. The E51 antibody blocks the interaction of gp120-CD4 complexes with CCR5 and binds to a highly conserved, basic gp120 element composed of the beta 19-strand and surrounding structures. Thus, on primary HIV-1 isolates, this gp120 region, which has been previously implicated in chemokine receptor binding, is accessible to a subset of CD4i antibodies.  相似文献   
944.
Ultrastructural and immunohistochemical findings in oral hairy leukoplakia   总被引:3,自引:0,他引:3  
Summary Three cases of HL from the lateral border of the tongue of male homosexual AIDS patients were investigated by thin section electron microscopy. Keratinocytes contained condensed chromatin in their pyknotic nuclei and a few organelles in the oedematous cytoplasm. Chromatin was in close association to the nuclear membrane and showed a punched-out appearance. Particles typical of the herpes virus group were abundant in the upper two thirds of the epithelium in all three cases. Virus particles were seen frequently in the nuclei of the ballooned keratinocytes, but rarely in cells containing Candida albicans. Viral nucleocapsids were observed budding at the inner nuclear membrane, thereby acquiring the prospective viral envelope. Complete, enveloped virions were found in the endoplasmic reticulum and in the extracellular space. These virions were identified immunohistochemically as Epstein-Barr virus (EBV) using two monoclonal antibodies directed against EBV capsid and membrane antigen, respectively. Candida albicans was observed in the stratum corneum and in the upper layer of the stratum spinosum. Special cytoplasmic tubular structures arranged in parallel bundles were found in koilocytotic cells in addition to characteristic membrane structures composed of undulating convoluted membranes. Epithelial basement membranes were always intact.This study was supported in parts by the Bundesministerium für Forschung und Technologie (grant No. II-022-86) and by an Alexander-von-Humboldt fellowship to Dr. Xiaolin Zhang  相似文献   
945.
A general procedure for isolating biologically active rubella virus antigens (VPI, Mr = 61,000; VP2, Mr = 45,000; VP3, Mr = 36,000) by monoclonal antibody affinity chromatography is described. Complexes formed between monoclonal antibodies and rubella virus antigens were found to be stable either at low pH or in Tris buffer containing detergent and high salt, but were efficiently dissociated by 5% diethanolamine, pH 11.5, or 50 mM lithium diiodosalicylate buffer, pH 8.0. Chromatographically purified rubella viral antigens retained their antigenicity as determined by enzyme-linked immunosorbent assays. Biological studies showed that rubella structural proteins VP2 and VP3 had no hemagglutinin function while the mixture of VP1 and VP2 and VP3 directly demonstrated hemagglutination activity. These results indicate that VP1 is at least in part responsible for the hemagglutinin function of rubella virus.  相似文献   
946.
根据独特型与抗独特型的免疫网络与免疫调节学说,利用狂犬病毒作为免疫原,设计了不同的动物免疫方案,免疫Balb/c小鼠,免疫脾细胞与骨髓瘤细胞经一次融合,同时获得了分泌抗狂犬病毒单克隆抗体杂交瘤及分泌狂犬病毒抗独特型单克隆抗体杂交瘤,为抗独特型抗体的制备开辟了一条简捷经济的途径。  相似文献   
947.
Zusammenfassung 63 Neugeborene wurden nach insgesamt 93 Austauschtransfusionen während eines Zeitraumes bis zu 6 Monaten auf das Risiko einer Transfusionshepatitis untersucht. Dabei wurden zusätzlich zur klinischen Beobachtung die Transaminasen und der Nachweis des Australia-Antigens als Kontrollkriterien gewertet. Klinisch wurde in keinem Fall eine Hepatitis beobachtet, eine SGPT-Erhöhung nach 3 Monaten in einem Fall könnte für eine anikterische Hepatitis sprechen. Ein Australia-Antigen-Nachweis konnte bei negativen Ausgangsbefunden bei Spendern und Empfängern nirgends in den Nachuntersuchungen erbracht werden. Demnach ist das Hepatitisrisiko einer Austauschtransfusion bei Wahrung der heute üblichen Spenderauslese praktisch nicht zu befürchten.  相似文献   
948.
Kapp  Markus 《Virus genes》1998,16(1):111-117
Viruses infecting algal hosts possess large double-stranded DNA as genomes. We have recently identified a family of viruses specific for filamentous brown algae. In contrast to the better known Chlorella viruses with their lytic infection cycle, marine brown algal viruses latently occur in their host cells and are induced to multiply in response to a variety of external stimuli such as change in light and temperature. Here, I summarize the known properties of this family of viruses and discuss their taxonomic classification.  相似文献   
949.
The use of cromolyn sodium (SCG) and high-dose theophylline (HDT) in the treatment of chronic perennial asthma in children is reviewed. It is noted that the regimens are only suitable for children with persistent symptoms uncontrolled by simpler forms of treatment. The methods of administration and dosage based on pharmacologic data are considered, and the potential importance of long-acting theophylline and nebulized cromolyn preparations is noted. Short-term studies have confirmed the efficacy of both drugs, and a comparative study showed little difference between them. Long-term studies of SCG have demonstrated its value to some 66% of children without serious side effects. No formal long-term studies have been carried out on HDT. Side effects from theophylline can often be eliminated by careful control of blood levels. From published evidence, neither SCG nor HDT is effective in steroid-dependent asthmatic children, and they contribute little, if anything, to management in such cases. The difference in cost of the drugs is small when all factors are considered, and either regimen is justified by the saving in medical expenses when used for carefully selected patients.  相似文献   
950.
目的 比较分析单纯急性戊型肝炎与重叠感染患者的肝功能指标和临床特点.方法 以40例单纯急性戊型肝炎为对照,回顾性分析了122例重叠感染戊型肝炎患者的肝功能指标、临床资料.结果 单纯戊肝组、甲戊重叠感染组、乙戊重叠感染组,三组之间ALT、AST、TBIL、DBIL差异均无统计学意义(P0.05),急性戊肝组与乙戊重叠感染组,甲戊重叠感染组与乙戊重叠感染组的白蛋白、球蛋白有统计学差异(P<0.01);甲戊重叠感染、乙戊重叠感染与单纯戊肝相比较临床合并症多、并发症重.结论 戊型肝炎重叠感染,特别是乙戊重叠感染患者,要加强临床监测,提高早期预防并发症的意识,以降低病死率.  相似文献   
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