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121.
To assess whether the semiquantitative peripheral blood Epstein-Barr virus (EBV) polymerase chain reaction (PCR) test correlates with post-transplant lymphoproliferative disorder (LPD), we compiled the results of the test done over a 3-year period ending July 1997. Six hundred seventy-six tests were done on 185 patients. Four hundred-thirty tests (63%) were negative, 167 (25%) were weak positive, 67 (10%) were moderate positive, and 12 (2%) were strong positive. Twelve of the patients developed a lymphoproliferative disorder (LPD) during this time. The EBV PCR tests proximate to the diagnosis of LPD in the 12 patients with EBV-positive LPD were 6 strong positive, 5 moderate positive, 1 weak positive. No patient with LPD had a negative result at diagnosis. Stated another way, 6/12 (50%) of strong-positive PCR tests, 5/67 (7%) moderate-positive tests, and 1/167 (.6%) of weak-positive tests correlated with LPD. Serologic evaluation for EBV done on 7 patients at the time of LPD showed low serologic responses in 5 of the 7 patients. The EBV PCR temporally associated with the serology indicated moderate to large viral burdens. In each patient evaluated serially, the EBV PCR test rose before the diagnosis of LPD and fell with treatment for the disorder. In conclusion, the EBV PCR test may be used as an adjunct to the diagnosis of patients with LPD and may be used to monitor response to therapy for the disorder. Received August 26, 1997; accepted January 13, 1998.  相似文献   
122.
Relatively little is still known about the sense of taste, or contact chemoreception, compared with other sensory modalities, despite its importance to many aspects of animal behaviour. The central projections of the sensory neurons from bimodal contact chemoreceptors (basiconic sensilla) were compared with those from mechanosensory tactile hairs located on similar regions of the middle leg of the locust. Basiconic sensilla are multiply innervated, containing one mechanosensory and several chemosensory neurons, whereas tactile hairs are innervated by a single mechanosensory neuron. We show that the sensory neurons from tactile hairs form a complete 3-dimensional somatotopic map in the mesothoracic ganglion. Sensory neurons from hairs located on the coxa projected to a region near the midline of the ganglion with neurons from hairs located on progressively more distal parts of the leg arborizing in successively more lateral regions of neuropil. All the neurons from basiconic sensilla, both mechanosensory and chemosensory, also projected in a similar, strictly somatotopic, manner, and the arbors from these neurons overlapped considerably with those from tactile hairs on equivalent parts of the leg to form a continuous region. Thus, the position of a receptor on the leg is preserved in the central nervous system not only for the mechanosensory neurons from both tactile hairs and basiconic sensilla but also for chemosensory neurons. We could observe no anatomical features or small differences in projection region between sensory neurons from individual basiconic sensilla consistent with differences in modality.  相似文献   
123.
BACKGROUND: Computer-assisted learning (CAL) offers a number of potential advantages for surgical technical skills teaching. The purpose of this study was to evaluate the impact of individualized external feedback on surgical skill acquisition when a CAL package is used for instruction. METHODS: Freshman and sophomore students participated in a 1-hour CAL session designed to teach them how to tie a two-handed square knot. One group received individualized external feedback during the session and the other group did not. Subjects were videotaped performing the skill before and after the session. The tapes were independently analyzed, in blinded fashion, by three surgeons. Three measures were obtained: the total time for the task, whether or not the knot was square, and the general quality of the performance using a rating scale. RESULTS: Data from 105 subjects were available for final analysis. For both groups there were significant increases in the proportion of knots that were square when the posttest performance was compared with the pretest performance but there was no difference between groups on this measure. Comparison of the performance scores demonstrated that both groups had a significant improvement after the session but the performance scores were significantly better in the group that had received feedback. CONCLUSIONS: Novices in both groups using CAL showed improvement in two of the outcomes measured, suggesting that subjects in both groups attained some degree of competence with this skill. The higher posttest performance score for the group receiving feedback demonstrates that external feedback results in a higher level of mastery when CAL is used to teach surgical technical skills.  相似文献   
124.
Speech and swallowing are important components of health‐related quality of life following head and neck cancer treatment. The aim of this study was to demonstrate the value of prospective multi‐centre evaluation by Speech and Language Therapists and to compare health‐related quality of life with speech and swallowing impairments. The University of Washington Head and Neck questionnaire version 4 (UW‐QOL) and Therapy Outcome Measures (TOM) were rated before and 6 months after cancer treatment in 95 patients from 12 centres. There was deterioration in TOM scores at 6 months. Pretreatment UW‐QOL swallowing was ranked equal first, with speech fourth. At 6 months speech was first and swallowing second. There were positive correlations between UW‐QOL swallowing and TOM dysphagia and between UW‐QOL speech and TOM laryngectomy, voice, phonology and dysarthria disorders. Both outcome measures are suitable for routine practice. Adaptation of TOM scales for use with head and neck cancer patients may improve sensitivity, validity and therapist compliance.  相似文献   
125.
Background: While mental health is a core part of primary care, there are few validated quality measures and little relevant internationally published research. Consensus panel methods are a useful means of developing quality measures where evidence is sparse and/or opinions are diverse. However, little is known about the dynamics of consensus techniques and the factors that influence the judgements and ratings of panels and individual panellists.  相似文献   
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Melton et al. (Melton GB, Petrila J, Poythress NG, Slobogin C: Psychological Evaluations for the Courts (ed 2). New York: Guilford, 1997) recently advocated the use of the Mental State at the Time of the Offense (MSE-Offense) measure not only as a screen for insanity evaluations but also as the sole measure in "obvious" cases of insanity. Given this recommendation for expanding the role of the MSE-Offense, the current authors have evaluated the available data based on its construction and validation. We found fundamental flaws in its development and grave shortcomings in its validation. Based on these limitations, we conclude that the MSE-Offense is unacceptable under the Daubert standard (Daubert v. Merrell Dow Pharmaceuticals, Inc., U.S. 113 S. Ct. 2786 (1993)) for either the screening or determination of criminal responsibility.  相似文献   
128.
An important factor influencing the pregnancy rate after in vitro fertilization-embryo transfer (IVF-ET) appears to be the number of embryos transferred to the uterus. In this study, the influence of oocyte maturity and embryo quality on pregnancy rate was assessed in patients undergoing IVF-ET. Ovarian hyperstimulation was performed by human menopausal gonadotropin (hMG [n = 29]), clomiphene citrate (CC)/hMG (n = 81), and hMG/follicle-stimulating hormone (FSH [n = 13]) protocols. Oocyte maturity was graded on a scale from 1 to 5 based on the morphology of the ooplasm, cumulus mass, corona radiata, and membrana granulosa cells. Embryos were graded according to the symmetry of the blastomeres and the presence or absence of fragmentation. Mature preovulatory oocytes yielded the highest fertilization rates. No differences were found among the protocols in terms of fertilization rate, embryo quality, or pregnancy rate. When all protocols were combined, patients who conceived had a significantly higher number of embryos transferred than those who did not conceive (3.6 +/- 0.1 [mean = SEM] versus 2.7 +/- 0.1). When embryo quality was compared, there was no difference in the number of "B" embryos transferred between patients who conceived and those who did not (1.2 +/- 0.2 versus 1.2 +/- 0.1), but the patients who conceived had significantly more "A" embryos transferred (1.6 +/- 0.3 versus 0.8 +/- 0.1). These data suggest that the treatment protocol did not determine embryo quality. Furthermore, the increase in pregnancy rates seen with an increase in embryos transferred is the result of the transfer of more "A" embryos.  相似文献   
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