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101.
Monoclonal antibodies (MCA) were obtained by immunizing BALB/c mice with 99% pure granulocytes from normal donors or with a whole leukocyte suspension obtained from a chronic myelogenous leukemia (CML) patient, and then fusing the mouse spleen cells with a 315–43 myeloma cell clone. Four MCA were selected and studied using ELISA, immunofluorescence, cytotoxicity assays, and FACS analysis. Antibodies 80H.1. 80H.3. and 80H.5 (from normals) and 81H.1 (from CML) detected antigens expressed on neutrophils. Antibodies 80H.1 and 80H.3 (lgG) also reacted with monocytes but not with other blood cell subsets. Antibodies 80H.5 and 81H.1 (lgM) were cytotoxic and reacted strongly with most of the cells of the neutrophil maturation sequence. i.e., myeloblasts, promyelocytes, myelocytes, and mature granulocytes. Antibodies 80H.5 and 81H.1 also inhibited BFU-GM and CFU-E. Antigens recognized by 80H.3. 80H.5, and 81H.1 were expressed both on a proportion of cells from HL.60, KG.1, ML.1, and K562 myeloid cell lines, and on a proportion of blast cells isolated from patients with acute myelogenous leukemia. They were not found on lymphoid cell lines or lymphoid leukemia cells. These MCA recognize either late differentiation antigens expressed on mature neutrophils and monocytes (80H.1 and 80H.3) or early differentiation antigens (80H.5 and 81H.1) specific to the granulocytic lineage. They may be useful for a better definition of those antigens specific to hematopoietic stem cells and their relationship with normal or neoplastic hematopoiesis.  相似文献   
102.
Studies that used the MMPI to predict the response of chronic low back pain patients to standard medical treatment have not produced definitive results. Patients seen in a university hospital orthopedic back pain clinic were given the MMPI before treatment, and 6 to 12 months later 76 patients completed follow-up forms that indicated their level of intensity during the previous week and their ratings of the success of treatment in relieving their pain as well as in enabling them to return to normal activities. Predictions of poor response were made in terms of either single MMPI scales or code types. Patients with poor outcome on two of the three criteria (level of pain intensity and ability to return to normal activities) had significantly higher scores on the Hs scale. The predicted high risk code types very accurately identified patients with poor response on the same two criteria; however, the code-type procedure overpredicted poor response in the good outcome group.  相似文献   
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BACKGROUND: Predictors of fertility or spermatogenesis during gonadotrophin therapy of gonadotrophin-deficient men remain poorly defined. METHODS AND RESULTS: In order to evaluate potential predictors, this study evaluated 29 consecutive gonadotrophin-deficient men all desiring paternity who received 43 courses of therapy in one centre between 1982 and 1998. The Kaplan-Meier survival analysis estimates of median (SE) time to a sperm concentration of >0, >5 and >20 x 10(6)/ml were 5.5 (1.1), 12.4 (2.3) and 29.1 (1.9) months respectively. Conception occurred in 22/43 cycles (with eight men achieving two pregnancies) with a median (SE) Kaplan-Meier estimate of 20.5 (4.7) months. The median sperm concentration at conception was 5.0 (SE 2.0; range 0.0-59.5) x 10(6)/ml. Multivariate correlated Cox proportional hazards models predicting these same sperm thresholds and conception were developed by forward stepwise variable selection with verification of the model by backward stepping. Larger testicular volume, prior gonadotrophin therapy, completion of puberty, older age, the absence of adverse fertility factors and the absence of multiple pituitary hormone deficiency predicted a favourable response. Multivariate modelling suggests that the two most important predictors of sperm output are testicular volume and pubertal status. The most important potentially modifiable predictor was prior gonadotrophin therapy. The efficacy of recombinant and urinary FSH were similar. Prior androgen therapy and partner's age did not appear to be significant. CONCLUSIONS: Since prolonged treatment may be required to induce spermatogenesis, attention to these predictors may allow appropriate early use of advanced reproductive technologies.  相似文献   
104.
Elevated blood pressure is an important risk factor for renal-, cerebro- and cardiovascular diseases. We used an efficient discordant sib-pair ascertainment scheme to investigate the impact of the distal end of the long arm of human chromosome 5 (chromosomal region 5q31.1-qter) containing genes for the alpha1B and beta2 adrenergic receptors and the dopamine receptor type 1A on variation of systolic blood pressure in young Caucasians. We measured eight highly polymorphic markers spanning this positional candidate gene-rich region in 427 individuals from 55 three-generation pedigrees containing 69 discordant sibling pairs, and calculated multipoint identity by descent (MIBD) probabilities. The results of genetic linkage and association tests indicate that the region between markers D5S2093 and D5S462 is significantly linked to one or more polymorphic genes influencing interindividual variation in systolic blood pressure levels. Since the alpha1B adrenergic receptor and dopamine receptor type 1A genes are located close to these markers, these data suggest that genetic variation in one or both of these G protein-coupled receptors, which participate in the control of vascular tone, plays an important role in influencing interindividual variation in systolic blood pressure levels.   相似文献   
105.
Kainate receptors have been studied extensively in vitro , but how they might function physiologically remains unclear. We studied kainate receptor modulation of synaptic responses in the rat ventrobasal thalamus using the novel antagonist LY382884 and the agonist ATPA (selective for GluR5-containing kainate receptors) as tools. No evidence could be found for a direct contribution of kainate receptors to responses of thalamic relay cells to lemniscal (sensory) input in thalamic slices studied with the aid of intracellular and field potential recordings, using selective AMPA and NMDA receptor antagonists and LY382884. However, the GluR5 agonist ATPA reduced the IPSPs originating from the thalamic reticular nucleus. Extracellular single-neurone recordings in anaesthetised rats showed that excitatory responses evoked by physiological vibrissa afferent stimulation were reduced by LY382884 applied iontophoretically at the recording site. This action of the antagonist was occluded when GABA receptors were blocked, indicating that the reduction in excitatory sensory responses by LY382884 is due to an action on GABAergic inhibition arising from the thalamic reticular nucleus. Further experiments showed that these actions depended on whether inhibition was evoked during activation of the excitatory receptive field rather than when inhibition was evoked from a surround vibrissa. We suggest that GluR5 is located presynaptically on inhibitory GABAergic terminals of thalamic reticular nucleus neurones, and that it is normally activated by glutamate spillover from synapses between excitatory afferents and relay neurones during physiological stimulation. We propose that this GluR5-activated disinhibition has an important novel role in extracting sensory information from background noise.  相似文献   
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A novel method for processing respiratory specimens to improve culture and acid-fast staining of mycobacteria is introduced. This new method utilized N,N-dimethyl-N-(n-octadecyl)-N-(3-carboxypropyl)ammonium inner salt (Chemical Abstract Service no. 78195-27-4), also known as C18-carboxypropylbetaine (CB-18). In a blinded, five-center study, CB-18-based processing was compared to the standard method combining NALC and NaOH (NALC/NaOH). A total of 573 respiratory specimens were tested. Individual specimens were split approximately equally; the host institutions processed half of each specimen by the NALC/NaOH method, while the other half was processed with CB-18 at Quest Diagnostics—Baltimore. A total of 106 specimens were culture positive for acid-fast bacilli (AFB). Replacement of the primary decontamination agent with CB-18 caused changes in all diagnostic parameters. Aggregate culture sensitivity improved by approximately 43% (P < 0.01), and smear sensitivity improved by approximately 58% (P < 0.01). The sensitivity of smear relative to that of M. tuberculosis isolates exceeded 93% (P < 0.01) when specimens were processed with CB-18. The average times to a positive result were reduced by 7.3 days in liquid culture (P < 0.01) and 5.3 days on solid media (P < 0.05); however, the CB-18 method had a 20.8% contamination rate in liquid culture versus a rate of approximately 7.5% with NALC/NaOH processing. There were also unusual reductions in liquid culture sensitivity and smear specificity among CB-18-processed specimens. The characteristics of the latter parameters suggested that refinement of the CB-18 processing method should allow further improvements in culture sensitivity. This study showed that the CB-18 method has the potential to improve both smear and culture detection for these important human pathogens.  相似文献   
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