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921.
应用地高辛标记探针原位杂交法和单克隆抗HCV-NS3-HRP建立直接酶标免疫组化法分别测定52例肝炎患者肝组织HCVRNA和HCAg-NS3。结果抗HCV阳性组HCVRNA检出率57.1%(16/28),HCAg-NS3检出率53.6%(15/28);抗HCV阴性组其两项检出率均为12.5%(3/24)。肝组织中HCVRNA阳性物呈蓝紫色细小颗粒存在于肝细胞核或胞浆内,其在肝小叶中的分布可分为3型,即弥漫型、局灶型、散在型。肝组织中HCAg-NS3阳性物呈棕黄色细小颗粒分布于肝细胞核或胞浆内,以单个或数个阳性细胞散布于肝小叶中。23例HCVRNA或/和HCAg-NS3阳性病例以肝炎后肝硬化(LC)病例占多数(14/23),其次为慢性重型肝炎(CSH)和中度慢性肝炎(CAH)。此两种检测方法具有较高符合率(90.4%,47/52),表明病毒核酸及其表达产物均存在于肝细胞内,与HCV感染密切相关。这为HCV感染诊断提供了直接依据,有利于研究HCV感染中病毒复制、慢性化进程、抗病毒治疗监测及重叠感染时病毒相互关系。 相似文献
922.
The association of hepatitis C virus (HCV) infection and tattooing was studied in 87 tattooed and 126 tattoo free healthy young men who did not engage in intravenous drug use or multiple sexual activity. Antibody against HCV (anti-HCV) was tested in serum specimens by enzyme immunoassay with C100-3, NS3, and core antigens; 11 of the 87 (12.6%) tattooed and 3 of the 126 (2.4%) tattoo free subjects were positive for anti-HCV (odds ratio = 5.9, 95% CI = 1.6-22.0). A relationship was demonstrated by an increased risk for HCV infection with an increasing number of tattooed site (P(trend) = 0.002). All but one of the 87 tattooed subjects had been infected by hepatitis B virus (HBV) and 25 were carriers of hepatitis B surface antigen (HBsAg). None of the 25 HBsAg carriers was positive for anti-HCV whereas 11 of the 62 HBsAg non-carriers had anti-HCV, suggesting a negative association between the HBsAg carriage and the long lasting anti-HCV (P = 0.02, Fisher's exact). The status of the tattooer was also an important determinant for HCV infection; the risk was higher if tattooing was done by a non-professional friend than by a professional tattooist. Tattooing, probably with improperly sterilized needles, can clearly pose an increased risk for HCV infection in Taiwan. This study indicates the need for legal standards for hygienic tattooing as part of preventive measures for the control of parenterally transmitted infections. 相似文献
923.
B. Kitzel R. W. Turner M. Burchhardt S. Poser G. Hunsmann T. Weber 《Journal of molecular medicine (Berlin, Germany)》1992,70(11):1013-1018
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
924.
Gary P. Zaloga Ulf R. Hierlwimmer Renata J. Engler 《The Journal of allergy and clinical immunology》1984,74(1):79-80
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
925.
Xiang SH Wang L Abreu M Huang CC Kwong PD Rosenberg E Robinson JE Sodroski J 《Virology》2003,315(1):124-134
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
926.
Xiaolin Zhang Angelika Langford Jürgen Becker Jörg-Peter Rabanus Hans-Dieter Pohle Peter Reichart Hans Gelderblom 《Virchows Archiv : an international journal of pathology》1988,412(6):533-542
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
927.
Purification of biologically active rubella virus antigens by immunoaffinity chromatography 总被引:1,自引:0,他引:1
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
928.
929.
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
930.
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