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81.
N. P. Kock H. Petersen T. Fenner I. Sobottka C. Schmetz P. Deplazes N. J. Pieniazek H. Albrecht J. Schottelius 《European journal of clinical microbiology & infectious diseases》1997,16(5):369-376
In view of the increasing number of cases of human microsporidiosis, simple and rapid methods for clear identification of microsporidian parasites to the species level are required. In the present study, the polymerase chain reaction (PCR) was used for speciesspecific detection ofEncephalitozoon cuniculi, Encephalitozoon hellem, Encephalitozoon (Septata) intestinalis, andEnterocytozoon bieneusi in both tissue and stool. Using stool specimens and intestinal biopsies of patients infected withEnterocytozoon bieneusi (n=9),Encephalitozoon spp. (n=2), andEncephalitozoon intestinalis (n=1) as well as stool spiked with spores ofEncephalitozoon cuniculi andEncephalitozoon hellem and tissue cultures ofEncephalitozoon cuniculi andEncephalitozoon hellem, three procedures were developed to produce PCR-ready DNA directly from the samples. Specific detection of microsporidian pathogens was achieved in the first PCR. The subsequent nested PCR permitted species determination and verified the first PCR products. Without exception, the PCR assay confirmed electron microscopic detection ofEnterocytozoon bieneusi andEncephalitozoon intestinalis in stool specimens and their corresponding biopsies and in spiked stool samples and tissue cultures infected withEncephalitozoon cuniculi andEncephalitozoon hellem. Moreover, identification ofEncephalitozoon spp. could be specified asEncephalitozoon intestinalis. Whereas standard methods such as light and transmission electron microscopy may lack sensitivity or require more time and special equipment, the PCR procedure described facilitates speciesspecific identification of microsporidian parasites in stool, biopsies, and, probably, other samples in about five hours. 相似文献
82.
目的探讨经炮制海芋散在复治肺结核中的作用。方法把102例多治病人随机分成两组。采用WHO推荐的复治方案3H3R3Z3E3/6H3R3E3为对照组(51例),将用复治方案3H3R3Z3E3/6H3R3E3,加口服经炮制海芋散作为治疗组(51例),对病例的症状体征、病灶吸收情况、空洞吸收和闭合情况、痰菌阴转情况及不良反应发生的情况进行观察研究。结果症状体征改变情况治疗组总有效率为96.0%,对照组为66.7%(P〈0.01);病灶吸收情况治疗组为96.1%,对照组为64.7%,治疗组明显高于对照组(P〈0.01):空洞吸收或闭合治疗组为98.0%,对照组为68.6%,治疗组明显高于对照组(P〈0.01);痰菌阴转情况治疗组为94.1%。对照组为70.5%,治疗组明显高于对照组(P〈0.05);不良反应发生情况治疗组为25.1%,对照组为52.2%.治疗组显著低于对照组(P〈0.01)。结论加服用经炮制海芋散联合抗痨化疗组合药物治疗复治肺结核的疗效优于单纯用抗痨化疗组合药的化疗方案,且可减轻抗痨化学药物的不良反应,作用肯定,值得在临床中进一步探讨研究。 相似文献
83.
Acute and long-term humoral immunity following active immunization of rabbits with inacctivated spores of various Encephalitozoon species 总被引:1,自引:0,他引:1
Sobottka I Iglauer F Schüler T Schmetz C Visvesvara GS Albrecht H Schwartz DA Pieniazek NJ Bartscht K Laufs R Schottelius J 《Parasitology research》2001,87(1):1-6
Microsporidia of the genus Encephalitozoon are increasingly being reported as a cause of severe, often disseminated infections, mainly in patients with acquired immunodeficiency
syndrome (AIDS). Immunological identification of each of the three recognized species (E. cuniculi, E. hellem, and E. intestinalis) requires the availability of specific immune sera. All sera available thus far have been generated by direct inoculation
of rabbits with virulent microsporidian spores. This study demonstrates for the first time that subcutaneous immunization
with inactivated spores of E. cuniculi, E. hellem, or E. intestinalis is capable of generating highly active rabbit hyperimmune sera to the homologous antigens, with maximal titers being 1:5,120,
1:1,280, and 1:2,560, respectively, as determined by the indirect immunofluorescence technique (IIF). Broad cross-reactivity
of the rabbit antisera with all heterologous Encephalitozoon antigens was determined by IIF and immunogold electron microscopy; however, only the E. hellem immune serum strongly cross-reacted with spores of Enterocytozoon bieneusi. During the 35-month follow-up period the antibody titers to the homologous antigens declined to 1:640, 1:160, and 1:320,
respectively. The observed decay curves for antibody titers against E. cuniculi, E. hellem, and E. intestinalis were fitted using mathematical modeling, resulting in a predicted duration for specific immune responses of about 7 years
on average. Knowledge of the magnitude and duration of specific immune responses is a prerequisite for further evaluation
of the concept of using inactivated microsporidian spores in the quest for vaccines against microsporidian infections.
Received: 10 April 2000 / Accepted: 18 July 2000 相似文献
84.
Guidelines for the validation and application of typing methods for use in bacterial epidemiology 总被引:3,自引:0,他引:3
A. van Belkum P. T. Tassios L. Dijkshoorn S. Haeggman B. Cookson N. K. Fry V. Fussing J. Green E. Feil P. Gerner-Smidt S. Brisse M. Struelens for the European Society of Clinical Microbiology Infectious Diseases Study Group on Epidemiological Markers 《Clinical microbiology and infection》2007,13(S3):1-46
85.
从人分离出两株甲型流感H9N2亚型毒株内部基因特性的研究 总被引:5,自引:1,他引:5
目的 了解2株从人分离出的H9N2亚型毒株内部基因特性,并弄清其来源。方法 用RT-PCR扩增目的基因,用P^CEM-T Vector(美国Promega公司),4℃过夜连接,重组质粒转入dH5a细菌,筛选阳性菌落,酶切鉴定,送六合通公司自动测序。然后进行进化树分析。结果 2株测定毒株内部基因均为G9基因系,它们相互间除PA基因有差异外,其余5个基因均相同。结论 2株测定毒株的基因组均为G9基因系,它们是由携带不同基因特性H9N2毒株的禽群分别直接感染人,而不是来自同一禽的H9N2亚型流感病毒。 相似文献
86.
Esaki Muthu Shankar Ramachandran Vignesh Kailapuri G Murugavel Pachamuthu Balakrishnan Ramalingam Sekar Charmaine AC Lloyd Suniti Solomon Nagalingeswaran Kumarasamy 《AIDS research and therapy》2007,4(1):1-7
Background
CD4+ T lymphocyte (CD4) cell count testing is the standard method for determining eligibility for antiretroviral therapy (ART), but is not widely available in sub-Saharan Africa. Total lymphocyte counts (TLCs) have not proven sufficiently accurate in identifying subjects with low CD4 counts. We developed clinical algorithms using TLCs, hemoglobin (Hb), and body mass index (BMI) to identify patients who require ART. 相似文献87.
McCaustland KA Krawczynski K Ebert JW Balayan MS Andjaparidze AG Spelbring JE Cook EH Humphrey C Yarbough PO Favorov MO Carson D Bradley DW Robertson BH 《Archives of virology》2000,145(9):1909-1918
Summary. Different patterns of disease were observed among 11 chimpanzees who were inoculated intravenously with hepatitis E virus
(HEV) positive fecal specimens from four different outbreaks (Nepal 1981, Uzbekistan 1981, Pakistan 1985, and Mexico 1986).
Five chimpanzees had marginal or no liver enzyme elevations within 70 days of inoculation. Two of the chimpanzees had limited
viremia, but did not produce detectable antibody. The four remaining chimpanzees had liver enzyme elevations, viral shedding,
viremia, seroconversion to anti-HEV, and detectable HEV antigen in liver biopsy specimens. These results may reflect the range
of infection patterns that develop in humans after natural exposure to the HEV.
Received December 29, 1999/Accepted February 21, 2000 相似文献
88.
89.
Nigel A. Cunliffe Bimal K. Das Madhumati Ramachandran Maharaj K. Bhan Roger I. Glass Jon R. Gentsch 《Virus genes》1997,15(1):39-44
We have sequenced the genes encoding the inner capsid protein VP6 and the nonstructural proteins NSP1 and NSP4 of the Indian
neonatal serotype P8[11]G9 human/bovine reassortant candidate vaccine rotavirus strain 116E. These three genes share a high
degree of sequence and deduced amino acid homology with human prototype strain Wa. Our results confirm and extend those of
previous RNA-RNA hybridization studies which suggested that these genes are of human origin, and will facilitate examination
of the host immune response to 116E induced by natural infection and vaccination.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
90.
抗HPT单克隆抗体的制备与生物学特性鉴定 总被引:1,自引:0,他引:1
目的:制备抗潮霉素B磷酸转移酶(HPT)的单克隆抗体(McAb),建立一种快速检测转基因作物中该选择标记基因HPT编码蛋白的方法。方法:用基因重组潮霉素B磷酸转移酶(HPT)抗原免疫BALB/C小鼠,采用杂交瘤技术制备McAb。选择不同的抗原决定簇与兔抗HPT多抗配对,建立双抗夹心ELISA检测HPT抗原。结果:筛选出四株稳定分泌抗HPT单抗的杂交瘤细胞株,IgG亚类鉴定均为IgG1,ELISA检测证实单抗可特异性识别细胞培养上清、重组子菌体裂解产物中及纯化出的HPT蛋白。结合位点测定实验表明4株单抗是针对不同的抗原决定簇,与多克隆抗体组成双抗夹心ELISA法,均可较好地检测到HPT抗原。检测的灵敏度为30ng/ml,且与别的无关抗原无交叉反应性。结论:4株杂交瘤细胞株特异性好,亲和力强,组成双抗夹心ELISA法可用于快速、灵敏检测HPT抗原。 相似文献