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31.
We examined the extent to which maternal antisocial behavior (ASB) is directly related to child conduct problems and social competence and assessed the potential mediating role of negative parenting. The sample included 93 adolescent mothers and their children (44 boys, 49 girls). Mothers retrospectively reported about their ASB since the child's birth, through Grade 2. Negative parenting was coded during a parent-child interaction task (PCIT) at Grade 2. Teachers assessed child outcomes at Grade 3. Maternal ASB during the child's life was directly related to parenting and both child outcomes. In the overall sample, negative parenting partially mediated the relation between maternal ASB and child conduct problems. However, the pattern of relations differed by sex. For boys, maternal ASB was directly related to conduct problems, independent of parenting. For girls, maternal ASB was strongly related to parenting but not conduct problems. Negative parenting did not mediate the relation between maternal ASB and child social competence. Implications for intervention and future research are discussed.  相似文献   
32.
Neuropeptides are found in specific subpopulations of primary afferent neurones. Peptide expression can be altered following axotomy or under the influence of nerve growth factor. Here we have examined the consequence of altering the peripheral target of afferent neurones. Many unmyelinated afferents from skin contain substance P-like immunoreactivity (SPLI) whilst those from muscle do not. We have found that fibres will innervate inappropriate tissue types. We have therefore cut and cross-anastomosed a skin and muscle hindlimb nerve in the rat and 10-12 weeks later analysed the regenerated nerves immunocytochemically for SPLI. Muscle afferents inappropriately reinnervating skin were found to contain many SPLI fibres in contrast to control nerves resutured to their own distal stumps. Conversely, skin afferents made to innervate muscle showed reduced levels of peptide staining. These results demonstrate the plasticity of peptide expression and suggest that factors in peripheral tissue or perhaps distal nerve sheaths exert a trophic influence on nervous system function.  相似文献   
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Hepatocellular carcinoma with osteoclast-like giant cells (hepatic giant cell carcinoma [HGCC]) is a rare entity, with only three cases reported. The tumor is histologically similar to giant cell tumor (GCT) of bone, and the origin of the multinucleated giant cells and mononuclear stromal cells has not been determined. The purpose of this report is to present a case of this rare tumor and compare its ultrastructural and immunohistochemical features with those of a conventional GCT of bone. Histologically, the HGCC consists of sheets of osteoclast-like giant cells with a background of mononuclear cells. The giant cells lack the pleomorphism seen in hepatocellular carcinomas with anaplastic giant cells. At the light microscopic level, most of this tumor was nearly identical to a GCT of bone, but several microscopic fields (less than 5% of the tumor) had the histologic appearance of a "usual" hepatocellular carcinoma. The hepatic tumor was negative for HAM 56, epithelial cytokeratins, muramidase, and alpha-1-antitrypsin, with only focal positivity for chymotrypsin in mononuclear and giant cells. The GCT was strongly positive for alpha-1-antitrypsin and chymotrypsin in both the mononuclear and giant cells and showed focal, weak staining for AE1 and AE3 in the mononuclear stromal cells. Ultrastructurally, both mononuclear and giant cells of the HGCC showed features typical of hepatocellular carcinoma. Although the patient presented in this report died, the pattern of growth was different from most hepatocellular carcinomas. The overall histologic features of this tumor are distinctive and appear to justify separating this variant from other types of hepatocellular carcinoma.  相似文献   
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Treatment of PC12 cells with chroquine (10-50 microM) obliterated the low intragranular pH, as detected by Acridine Orange fluorescence, and depleted the cells of dopamine and norepinephrine. However, these concentrations of chloroquine did not prevent the release of the newly synthesized proteins which normally undergo stimulus-coupled secretion with the catecholamines. Higher concentrations of chloroquine (200 microM) and ammonium chloride (10 and 25 mM) inhibited the release of most of these proteins. This inhibition did not result from alterations in protein synthesis, since the profile of proteins synthesized was not substantially altered. Nor did the inhibition result from degradation of the neurosecretory proteins, since prelabeled proteins were capable of undergoing stimulated secretion from chloroquine-treated cells, as from normal cells. The findings indicated that the inhibition was at the step of packaging of the proteins into the neurosecretory granules. While release of the major secretory proteins, including chromogranin B, was inhibited with 200 microM chloroquine, chromogranin A was secreted upon stimulation of these cells. The results of this study indicate that an acidic intragranular pH is not a requirement for the packaging and secretion of neurosecretory proteins. Higher concentrations of chloroquine had a differential effect on the regulated secretion of different neurosecretory proteins.  相似文献   
38.
The aim of this study was to compare 70 couples who had conceived by in- vitro fertilization (IVF) with 63 matched controls for the prevalence of anxiety and quality of attachment to the baby during pregnancy. Results for mothers showed no group differences using a global measure of anxiety, the Spielberger State-Trait Anxiety Inventory. However, pregnancy-specific measures revealed significantly higher levels of anxiety in IVF mothers about the survival and normality of their unborn babies, about damage to their babies during childbirth and about separating from their babies after birth. When IVF mothers were differentiated according to the number of treatment cycles, more differences in anxiety level were revealed, with most increases occurring in mothers who had experienced two or more treatment cycles. IVF fathers did not differ from controls on the global anxiety measure. No data on pregnancy-specific anxiety were available for fathers. Neither IVF mothers nor IVF fathers differed from controls on measures of attachment to the baby during pregnancy. Results are discussed in the context of the need for researchers to employ differentiated and issue-specific measures to identify concerns that may be unique to IVF couples. Clinical implications regarding the need for psychological support during pregnancy are also discussed.   相似文献   
39.
We performed a multicenter, randomized, controlled clinical trial of therapeutic peritoneal lavage (2 liters per hour for three days) in 91 patients with severe acute pancreatitis. Patients were entered into the study if severe pancreatitis was indicated by multiple laboratory criteria or diagnostic peritoneal lavage. All patients received full supportive treatment. The median time between the onset of symptoms and randomization was 38 hours. Forty-six patients were assigned to the control group and 45 to the lavage group. There were 13 deaths (28 per cent) and 16 patients with major complications (35 per cent) in the control group, as compared with 12 deaths (27 per cent) and 17 patients with major complications (38 per cent) in the lavage group. Lavage did not appear to modify the length of survival, the incidence of pancreatic collections (pseudocysts or abscesses), or the plasma amylase concentration. Considering the statistical power of the design, we conclude that the outcome of severe pancreatitis was not greatly, if at all, influenced by the regimen of peritoneal lavage used in this study.  相似文献   
40.
BACKGROUND: Concerns about possible adverse outcomes for children conceived using ICSI were highlighted in 1998 when 1-year-old ICSI children were found to be at increased risk (relative risk = 9.2) of delayed mental development compared with children conceived naturally or using IVF. As the findings were biologically plausible, it was considered important to reassess child development when a more accurate measure of long-term cognitive ability could be obtained. METHODS: The mental development of 97 ICSI, 80 IVF and 110 naturally conceived (NC) children at 5 years of age was assessed using intelligence quotients (IQ) obtained from the Wechsler Preschool and Primary Scales of Intelligence. RESULTS: The mean full-scale IQ was 110 +/- 18 for ICSI, 111 +/- 13 for IVF and 114 +/- 13 for NC children (P = 0.21, non-significant). ICSI children were not at increased risk for delayed (full-scale IQ <85) cognitive development (ICSI 5.2%, IVF 2.5%, NC 0.9%; P = 0.18, non-significant). The only significant independent predictor of below-average full-scale IQ on multivariate analysis was lower maternal education level. CONCLUSIONS: These findings suggest that the genetic influence of parental cognitive ability is more important than the mode of conception in determining the long-term intellectual ability of children conceived using ICSI.  相似文献   
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