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81.
Summary The development ofEimeria dispersa Tyzzer, a parasite of bobwhite quail, in Madin-Darby bovine kidney cell cultures was investigated. Excysted sporozoites were inoculated into Leighton tubes containing cell monolayers on glass coverglasses and maintained in minimum essential medium supplemented with heat-inactivated fetal calf serum. Sporozoites became intracellular within 2 h. Sporozoite-shaped schizonts, schizonts with developing merozoites, and mature first-generation schizonts were seen 24 h postinoculation. Intracellular first-generation merozoites, second-generation trophozoites, and early second-generation schizonts containing two nuclei were first observed 72 h postinoculation. Second-generation schizonts containing developing merozoites as well as mature second-generation schizonts were first seen 96h postinoculation. Gametogony was not observed.DM developing merozoite - HN host nucleus - IM intracellular merozoite - M merozoite - N nucleus - R refractile body - RB residual body - V parasitophorous vacuole  相似文献   
82.
AIMS: To develop a method of processing non-formalin fixed prostate specimens removed at radical prostatectomy to obtain fresh tissue for research and for correlating diagnostic and molecular results with preoperative imaging. METHODS/RESULTS: The method involves a prostate slicing apparatus comprising a tissue slicer with a series of juxtaposed planar stainless steel blades linked to a support, and a cradle adapted to grip the tissue sample and receive the blades. The fresh prostate gland is held in the cradle and the blades are moved through the cradle slits to produce multiple 4 mm slices of the gland in a plane perpendicular to its posterior surface. One of the resulting slices is preserved in RNAlater. The areas comprising tumour and normal glands within this preserved slice can be identified by matching it to the haematoxylin and eosin stained sections of the adjacent slices that are formalin fixed and paraffin wax embedded. Intact RNA can be extracted from the identified tumour and normal glands within the RNAlater preserved slice. Preoperative imaging studies are acquired with the angulation of axial images chosen to be similar to the slicing axis, such that stained sections from the formalin fixed, paraffin wax embedded slices match their counterparts on imaging. CONCLUSIONS: A novel method of sampling fresh prostate removed at radical prostatectomy that allows tissue samples to be used both for diagnosis and molecular analysis is described. This method also allows the integration of preoperative imaging data with histopathological and molecular data obtained from the prostate tissue slices.  相似文献   
83.
BACKGROUND. Intravenous amphotericin B, with or without flucytosine, is usually standard therapy for cryptococcal meningitis in patients with the acquired immunodeficiency syndrome (AIDS). Fluconazole, an oral triazole agent, represents a promising new approach to the treatment of cryptococcal disease. METHODS. In a randomized multicenter trial, we compared intravenous amphotericin B with oral fluconazole as primary therapy for AIDS-associated acute cryptococcal meningitis. Eligible patients, in all of whom the diagnosis had been confirmed by culture, were randomly assigned in a 2:1 ratio to receive either fluconazole (200 mg per day) or amphotericin B. Treatment was considered successful if the patient had had two consecutive negative cerebrospinal fluid cultures by the end of the 10-week treatment period. RESULTS. Of the 194 eligible patients, 131 received fluconazole and 63 received amphotericin B (mean daily dose, 0.4 mg per kilogram of body weight in patients with successful treatment and 0.5 mg per kilogram in patients with treatment failure; P = 0.34). Treatment was successful in 25 of the 63 amphotericin B recipients (40 percent; 95 percent confidence interval, 26 percent to 53 percent) and in 44 of the 131 fluconazole recipients (34 percent; 95 percent confidence interval, 25 percent to 42 percent) (P = 0.40). There was no significant difference between the groups in overall mortality due to cryptococcosis (amphotericin vs. fluconazole, 9 of 63 [14 percent] vs. 24 of 131 [18 percent]; P = 0.48); however, mortality during the first two weeks of therapy was higher in the fluconazole group (15 percent vs. 8 percent; P = 0.25). The median length of time to the first negative cerebrospinal fluid culture was 42 days (95 percent confidence interval, 28 to 71) in the amphotericin B group and 64 days (95 percent confidence interval, 53 to 67) in the fluconazole group (P = 0.25). Multivariate analyses identified abnormal mental status (lethargy, somnolence, or obtundation) as the most important predictive factor of a high risk of death during therapy (P less than 0.0001). CONCLUSIONS. Fluconazole is an effective alternative to amphotericin B as primary treatment of cryptococcal meningitis in patients with AIDS. Single-drug therapy with either drug is most effective in patients who are at low risk for treatment failure. The optimal therapy for patients at high risk remains to be determined.  相似文献   
84.
85.
Exposure of rat hippocampal slices to perfusate containing 1-2 mM glutamate (GLU) induces reversible and relatively selective blockade of excitatory transmission. Intracellular recordings from 20 region CA1 hippocampal cells demonstrated only transient and mild effects on resting membrane properties and action potentials. In contrast, in 2 mM GLU excitatory postsynaptic potentials declined to 28% of control (P less than 0.001); inhibitory postsynaptic potentials remained robust at 88% of control. This suggests that excess exposure to GLU may result in a selective 'down-regulation' of excitatory synaptic transmission, while preserving inhibitory pathways. These observations may have practical implications for development of new anticonvulsant drugs.  相似文献   
86.
Monoclonal antibodies were produced using mice immunized with the human promyeloid cell line HL60. Two antibodies are described which identify antigens selectively expressed by myeloid cells. Studies using normal bone marrow and myeloid leukaemia cells demonstrated that one of these antibodies (AGF4.48) identifies an antigen expressed throughout the promyeloid to neutrophil stages of maturation. In contrast, the second antibody (AGF4.36) identifies an antigen expressed at the promyeloid to metamyeloid stages and is absent from most blood neutrophils. The HL60 line can be induced to differentiate into neutrophils by 1 . 25% dimethylsulphoxide (DMSO) (Collins et al., 1978). Variant lines from HL60, unresponsive to 1 . 25% DMSO, lack the 'transient' myeloid antigen (AGF4.36) and show a reduced expression of the myeloid antigen (AGF4.48). The variant lines can be induced to mature using higher DMSO concentrations (1 . 5-1 . 75%) and do not express the 'transient' antigen (AGF4.36) during their maturation. The use of these lines in studies of myelopoiesis is discussed.  相似文献   
87.
Association of DLG5 R30Q variant with inflammatory bowel disease   总被引:6,自引:0,他引:6  
Crohn's disease (CD) and ulcerative colitis (UC) are chronic inflammatory diseases of the gastrointestinal system known as the inflammatory bowel diseases (IBD). Recently, Stoll and colleagues reported a novel finding of genetic variation in the DLG5 gene that is associated with IBD (CD and UC combined). We present here a study of the genetic variation described in that report in two well-powered, independent case-control cohorts and one family-based collection, and confirm the proposed association between IBD and the R30Q variant of DLG5 in two of the three studies. We are, however, unable to replicate the other proposed association to the common haplotype described in Stoll et al and suggest that this other finding could conceivably have been partially a statistical fluctuation and partially a result of LD with the replicated R30Q association. This study provides support for the hypothesis that DLG5 constitutes a true IBD risk factor of modest effect.  相似文献   
88.
The relationship between parental constitutional chromosome abnormalities and the development of hydatidiform mole was evaluated in series from four institutions. Karyotype analysis was performed on blood samples from 237 patients with a pathological diagnosis of complete mole and 217 of their spouses. One patient was found to have a constitutional balanced translocation, t(11;18), while one spouse was found to have a balanced translocation, t(4;20). Among 125 patients with partial mole and 106 of their spouses, one male was found to be a translocation carrier, t(13;14). No significant increase in the frequency of translocations in the parents of complete moles was found in any of the series considered separately or together. Data from the combined series show no evidence of constitutional parental chromosome aberrations as an aetiological factor in the development of molar pregnancies.  相似文献   
89.
90.
A personal computer based system for data acquisition and analysis appropriate to physiological experiments is described in detail. The system is independent of the details of the analog signal generation. The software, written in C, is modular and easily portable to other PC systems. The system is capable of: (a) sampling many analog signals at an appropriate rate (100 Hz), (b) storing large quantities of digitized data, (c) analysing digitized waveforms to obtain signal parameters, and (d) storing signal parameters in a format suitable for statistical analysis. Computer processed cardiopulmonary data are compared with data derived from standard ICU equipment.  相似文献   
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