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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
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人体蠕形螨的生物学研究 总被引:4,自引:0,他引:4
用透明胶带法观察蠕形螨在人体面部的寄生、逸出及其在体外的存活能力。结果表明:毛囊蠕形螨(Demod-exfoliculorum,D.f.)主要以颚体朝向毛囊底部寄生,且常常有多条群居现象,而皮脂蠕形螨,(Demodexbrevis,D.b.)一般为单条独居生活。两种人体蠕形螨昼夜均可主动爬出毛囊口出现在皮肤表面,D.f.以白天1000~1800为逸出高峰;D.b.则以夜间2200~200逸出最多。此外,蠕形螨在体外有较强的活动力和存活力。透明胶带法在人体蠕形螨的流行病学调查和生物学研究方面具有较高的应用价值 相似文献
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本实验制作不同程度心肌缺血的动物模型,以声处理5%人血白蛋白为超声造影剂进行心肌灌注造影,探讨MCE时间-强度曲线各指标与心肌缺血程度间的关系。结果表明:心肌显影的峰值强度和曲线下面积均与缺血程度呈显著负相关(相关系数分别为r=-0.98,P值<0.005;r=-0.94,P值<0.05),且能区分轻度、中度和重度三种程度的心肌缺血;而三项时间指标与心肌缺血程度间未发现显著性差异。本实验的初步结果表明,MCE是一项活体评估局部心肌血流灌注的有效方法。 相似文献
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Galanin-like immunoreactivity has been visualized in nerve fibers in the islets of Langerhans, suggesting an involvement of
galanin in the neural regulation of islet function. In this study, we investigated the effects of galanin on basal and stimulated
insulin and glucagon secretion by infusing the peptide at three different dose rates in rats. We also studied the direct effect
of galanin on insulin secretion from freshly isolated rat islets. At 320 pmol/kg/min, but not at 20 or 80 pmol/kg/min, galanin
lowered basal plasma insulin levels. In contrast, basal plasma glucagon levels were lowered by galanin already at 20 and 80
pmol/kg/min. Furthermore, galanin inhibited both glucose- and arginine-induced insulin release at all three dose levels, whereas
arginine-induced glucagon release was not affected by galanin. Glucose-stimulated insulin secretion from isolated rat islets
was dose-dependently suppressed by galanin (10-6-10-8M). Therefore, it is concluded that galanin in rats inhibits insulin secretion, both in vivo and in vitro, and that at lower
dose levels, the peptide also inhibits basal glucagon release. 相似文献
5.
Erik D Skarsgard Ying C MacNab Zhenguo Qiu Ruth Little Shoo K Lee 《Journal of perinatology》2005,25(5):315-319
OBJECTIVE: Outcomes analysis in congenital diaphragmatic hernia (CDH) requires a validated risk-adjustment tool. The purpose of this study was to use the Canadian Neonatal Network (CNN) database to validate the Score for Neonatal Acute Physiology, Version II (SNAP-II) for prediction of mortality among CDH infants admitted to a neonatal intensive care unit (NICU), and to compare this to the predictive equation recently developed by the Congenital Diaphragmatic Hernia Study Group (CDHSG). STUDY DESIGN: Infants with CDH in the CNN database were identified. Bivariate and multivariable logistic regression models were used to identify risk factors predictive of mortality. Model predictive performance and calibration were assessed using the area under the receiver operator characteristic curve and the technique of Hosmer-Lemeshow, respectively, and compared with the CDHSG predictive equation. RESULTS: There were 88 patients with CDH among 19,507 admissions to CNN hospitals. The mortality rate among CDH patients surviving to NICU admission was 17%, and 12.5% received extracorporeal membrane oxygenation therapy. Gestational age and admission SNAP-II score predicted mortality. Model predictive performance and calibration were optimized with these variables combined. The CDHSG equation was equally predictive of mortality, but was only marginally calibrated. CONCLUSIONS: SNAP-II is highly predictive of mortality among patients with CDH, and can be used to risk-adjust these patients. 相似文献
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We report a case of extragastrointestinal stromal tumor possibly originating from the prostate. The patient underwent radical prostatectomy because of no metastatic evidence. No recurrence and metastasis have been found during 14 months of follow up. To our knowledge, this may be the third such case published in a report in terms of pathological type. 相似文献
9.
Twenty cases of microglandular hyperplasia (MGH) of the uterine cervix and 14 cases of low-grade (nuclear) mucinous adenocarcinoma of the endometrium (MA) were compared morphologically and immunohistochemically. Subnuclear vacuoles were seen in 10 cases of MGH but were absent in all MA. Luminal squamous metaplasia was seen in only 10% of MGH cases versus 65% of MA cases. Stromal foam cells were present in 36% of MA but were absent in MGH cases. Both MGH and MA had minimal variation in nuclear size and inconspicuous nucleoli. As many as 8 mitoses/10 high-power fields (MF/10 HPF) were found in MA compared with 3 or fewer MF/10 HPF in MGH. Vimentin was expressed in 90% of MA but was absent in MGH. A significantly higher percentage of MA cells stained with MIB-1 than did those of MGH (mean 11% versus 0.5%). Both MA and MGH lacked CEA and p53 staining, whereas both had variable expression of ER and PR with no significant differences except that PR was absent in 40% of MGH cases. Our findings indicate that in the differential diagnosis of MGH versus MA, the presence of subnuclear vacuoles favors the former, whereas luminal squamous metaplasia, stromal foam cells, mitotic activity, vimentin expression, and MIB-1 expression favor the latter. 相似文献
10.
Patricia K P Burnell Lars Asking Lars Borgstr?m Steve C Nichols Bo Olsson David Prime Ian Shrubb 《Journal of aerosol medicine》2007,20(3):269-281
Magnetic resonance imaging (MRI) of the oropharyngeal region from 20 adult volunteers using four model inhalation devices (varying mouthpiece diameters, airflow resistances) and tidal breathing was carried out. Statistical analysis (convex hull method) selected 12 scans from 80 data sets representing the extremes of all dimensions in the population. Twelve physical mouth-throat models were made by stereolithography using the exact scan data. The aim was to produce models with varying dimensions to span the adult population, and to investigate if oropharyngeal dimensions affected throat retention for different delivery systems. In an in vitro analysis, the models were used to determine the retention effect of the oropharyngeal airspaces when drug aerosols were administered from four inhalation delivery systems: a pressurised metered dose inhaler (pMDI), two different dry powder inhalers (DPIs A and B), and a nebulizer. The aims of this work were to determine the key parameters governing mouth-throat retention and whether retention was dependent on the delivery system used. Characterizing the throat models by measuring 51 different dimensional variables enabled determination of the most influential variables for dose retention for each inhalation delivery system. Throat model retention was found to be dependent on the delivery system (pMDI approximately DPI(A) > DPI(B) > Neb.). The most influential variable was the total throat model volume. Throat models representing high, median, and low oropharyngeal filtration in healthy adults have been identified. 相似文献