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81.
We tested the hypothesis that astrocytic matrix metalloproteinase-9 (MMP-9) mediates hemorrhagic brain edema. In a clinical case of hemorrhagic stroke, MMP-9 co-localized with astrocytes and neurons in peri-hematoma areas. In a mouse model where blood was injected into striatum, MMP-9 was colocalized with astrocytes surrounding the hemorrhagic lesion. Because MMP-9 is present in blood as well as brain, we compared four groups of wild type (WT) and MMP-9 knockout (KO) mice: WT blood injected into WT brain, KO blood into KO brain, WT blood into KO brain, and KO blood into WT brain. Gel zymography showed that MMP-9 was elevated in WT hemorrhagic brain tissue but absent from KO hemorrhagic brain tissue. Edematous water content was elevated when WT blood was injected into WT brain. However, edema was ameliorated when MMP-9 was absent in either blood or brain or both. To further assess the mechanisms involved in astrocytic induction of MMP-9, we next examined primary mouse astrocyte cultures. Exposure to hemoglobin rapidly upregulated MMP-9 in conditioned media within 1 to 24 h. Hemoglobin-induced MMP-9 was reduced by the free radical scavenger U83836E. Taken together, these data suggest that although there are large amounts of MMP-9 in blood, hemoglobin-induced oxidative stress can trigger MMP-9 in astrocytes and these parenchymal sources of matrix degradation may also be an important factor in the pathogenesis of hemorrhagic brain edema.  相似文献   
82.
Background  High-quality attenuation maps are critical for attenuation correction of myocardial perfusion single photon emission computed tomography studies. The filtered backprojection (FBP) approach can introduce errors, especially with low-count transmission data. We present a new method for attenuation map reconstruction and examine its performance in phantom and patient data. Methods and Results  The Bayesian iterative transmission gradient algorithm incorporates a spatially varying gamma prior function that preferentially weights estimated attenuation coefficients toward the soft-tissue value while allowing data-driven solutions for lung and bone regions. The performance with attenuation-corrected technetium 99m sestamibi clinical images was evaluated in phantom studies and in 50 low-likelihood patients grouped by body mass index (BMI). The algorithm converged in 15 iterations in the phantom studies. For the clinical studies, soft-tissue estimates had significantly greater uniformity of mediastinal coefficients (mean SD, 0.005 cm−1 vs 0.011 cm−1; P<.0001). The accuracy and uniformity of the Bayesian iterative transmission gradient algorithm were independent of BMI, whereas both declined at higher BMI values with FBP. Attenuation-corrected perfusion images showed improvement in myocardial wall variability (4.8% to 4.1%, P=.02) for all BMI groups with the new method compared with FBP. Conclusion  This new method for attenuation map reconstruction provides rapidly converging and accurate attenuation maps over a wide spectrum of patient BMI values and significantly improves attenuation-corrected perfusion images.  相似文献   
83.
目的 探讨转化生长因子β(TGF-β)对人的颈椎关节突关节透明软骨细胞基质金属蛋白酶13(MMP-13)基因表达的作用,旨在阐明颈椎退行性变的相关发生机理。方法 应用逆转录方法PCR及实时荧光定量方法,检测不同浓度TGF-β作用传代培养人的透明软骨细胞MMP-13mRNA的含量。另外3种不同浓度分别与10ng/ml IL-1β组成联合作用组,共计6个实验组及1个正常对照组。结果 正常对照组中透明软骨细胞仅见MMP-13mRNA扩增产物,实验组TGF-β1、10和100ng/ml作用12h后,MMP-13mRNA表达逐渐增强;而联合作用组中,随着TGF-β1浓度的升高,MMP-13mRNA表达逐渐降低,并且各组之间存在明显的差异(P〈0.05)。结论 TGF-β可按剂量依赖方式调节颈椎关节突关节软骨细胞MMP-13mRNA的表达。  相似文献   
84.
We present an adenoid cystic carcinoma of the base of tongue in a 48-year-old male with a restricted chromosomal alteration by cytogenetic and spectral karyotypic analysis (SKY). SKY and G-banding analyses identified the t(6;14)(q25;q13) as the sole structural aberration in all metaphases analyzed. This finding supports a critical role for this event in the development of this tumor. The implications of chromosome 6q translocation in this case and in previously reported adenoid cystic carcinomas are highlighted and discussed.  相似文献   
85.
肠道T细胞淋巴瘤临床分析   总被引:1,自引:0,他引:1  
本文总结报告了3例肠道T细胞淋巴瘤(intestinal T-cell lymphoma,ITCL)的诊治资料,并结合文献复习,发现IT—CL多见于中年男性,以腹痛、血便、发热、体质量下降为主要症状,治疗效果差,预后不良。病理改变以肠道溃疡形成为特点,溃疡形态呈多形性、多灶性、不规则,镜下瘤细胞明显异型、弥漫性浸润,中至大细胞多见。肿瘤细胞呈T细胞表型。ITCL临床少见,缺乏特异性临床表现,极易误诊。故临床医师应重视对ITCL临床病理特征、免疫表型和基因型的研究,注意识别,促其早期诊治。  相似文献   
86.
87.
BACKGROUND: During formation of prolactin neoplasia, how cells and its structure in adenohypophysis affect prolactin cells should be further studied. Intermediate lobe can be regarded as a driving region to release prolactin (PRL) and may promote formation of prolactin neoplasia in pituitary anterior lobe. OBJECTIVE: To observe the effect of diethylstilbestrol (DES) on the expressions of μ and m-calpains in pituitary intermediate lobe of female Wistar rats. DESIGN: Observational contrast animal study. SETTING: Beijing Neurosurgical Institute. MATERIALS: A total of 21 female Wistar rats, 3 weeks old weighing 70–80 g were housed with free access to tap water and standard pellet food. They were kept in a CL-grade condition, at (24±1)℃ and a humidity of (55±5)%, and with a 12 hours day-night cycle. Caprine anti-μ- and m-calpains antibodies were provided by Santa Cruz Biotechnology, CA, USA; rabbit-anti-PRL antibodies by Dako, Denmark; rabbit-anti-ACTH antibody by Boster Company, Wuhan. METHODS: The experiment was carried out in Pathophysiological Department and Animal Laboratory, Beijing Neurosurgical Institute from August 2006 to January 2007. ① Rats were randomly divided into groups with 7 in each group, including vehicle control group, in which rats were injected intraperitoneally with sun-flower seed oil (1 mL/kg, twice a week) for 16 weeks; DES group, where animals were administered with DES (5 mg/kg, twice a week) for 16 weeks; DES + vehicle control group, in which DES was administered for 12 weeks at the same dose with those in DES group, and then was discontinued and replaced by sun-flower seed oil (1 mL/kg, twice a week) for the following 4 weeks. ② At 16 weeks later, pituitary tissue was dealt with HE staining and PRL immunohistochemical examination to observe evoke of tumor; meanwhile, immunohistochemical examination was used to observe expression of PRL of pituitary anterior lobe, expressions of μ- and m-calpains of pituitary intermediate lobe and distribution of adrenocorticotropin. MAIN OUTCOME MEASURES: ① Expression of PRL of pituitary anterior lobe, expressions of μ- and m-calpains of pituitary intermediate lobe and distribution of adrenocorticotropin. ② Morphological observation of pituitary tissue. RESULTS: All 21 rats were involved in the final analysis. ① Results of immunohistochemical examination: Morphological changes of neoplasia in DES group were strongly positive to PRL, and this suggested that formation of prolactin adenoma was observed in pituitary tissue. As compared with vehicle control group, expression of adrenoeorticotropic hormone (ACTH) was increased in both DES group and DES + vehicle control group. In addition, expressions of μ- and m-calpains in pituitary intermediate lobe were higher in DES group than that in vehicle control group. Otherwise, expressions of m-calpains in pituitary intermediate lobe was decreased in DES + vehicle control group, but expression of μ-calpains was still increased. ② Morphological observation of pituitary tissue: Gland tubes were orderly arranged in rats in vehicle control group. Anterior pituitary gland in rats of DES group demonstrated an apparent disappearance of gland tubes and a relatively large-scaled vasculature formation, namely the vascular lake lined by tightly arranged endothelial cells. Local integrated tumor cell arrangements were also detected. In addition, the border between the IL and the anterior lobe was locally blurred. The definite tumor-like changes in pituitary tissues were confirmed in 6 of 7 female Wistar rats in DES group, and one spontaneous occurrence of tumor formation was found in vehicle control group. In DES + vehicle control group, DES withdrawal led to the subtile emergence of gland tube cavity, although tumor-like cells still existed in 4 of 7 rats, suggesting occurrence of the tumor regression due to the withdrawal of DES. CONCLUSION: A long-term application of DES can enhance the expressions of ubiquitours neutral cysteine protease in pituitary intermediate lobe and this suggests that both of them play a key role in release of hormone and formation of prolactin neoplasia through directly promoting PRL expression and release of neighboring pituitary intermediate lobe.  相似文献   
88.
医疗质量效益监控和评价的根本依据是医疗质量评价指标,指标的确定及其涵盖内容直接关系到医疗质量管理以及医院核心竞争力。因此,如何构建一套科学、合理、可操作的质量效益指标评价体系,是医院质量管理、质量效益目标责任管理要探索的课题。20世纪90年代初期,我院开始实行以工作量和经济指标为主的经济考核办法,在相当一段时间内发挥了较好的管理效能和效果。随着社会发展和医疗卫生改革的深入,以工作量和经济指标为主的考核办法其作用逐渐趋弱,弊端也日益显露。  相似文献   
89.
目的 了解抗菌药物应用的基本情况。方法 将 2 0 0 1年 3月 14 3 0例住院患者病历与 2 0 0 4年 3月的 2 0 66例住院患者病历进行回顾性调查和对比分析。结果  2 0 0 1年的 14 3 0例中有 948(66 3 % )例 ,和 2 0 0 4年的 2 0 66例有 10 60例 (5 1.3 % ) ,应用了抗菌药物。结论 定期检查考评 ,严格掌握用药指征 ,是加强抗菌药物应用管理的关键。  相似文献   
90.
Methyl tert-butyl ether which is a powerful cholesterol monohydrate solvent does not completely dissolve mixed cholesterol gallstones when directly infused into the biliary tree. In this work, we compared the effect of various solvents containing different proportions of methyl tert-butyl ether and dimethylsulfoxide in anhydrous and aqueous systems on the in vitro solubilization of human cholesterol stones. The dissolution rates of cholesterol obtained in the presence of methyl tert-butyl ether was markedly decreased when 10 p. 100 water was added. In contrast, the addition of dimethylsulfoxide (30 p. 100) to methyl tert-butyl ether-water system enhanced the stone-solvent contact, improved the cholesterol dissolution rates and left less stone debris. A subsequent dissolution with an alkaline, pH = 8.8, aqueous dimethylsulfoxide-ethylenediaminetetraacetic acid solution strongly reduced the non cholesterol residues. In vivo, nearly complete dissolution of human cholesterol stones implanted in the gallbladder of rabbits was obtained within 8 hours when methyl tert-butyl ether/dimethylsulfoxide (70/30) solvent was infused at a rate of 0.6 ml/h/kg. With methyl tert-butyl ether, only 84 p. 100 of the original stone weight was dissolved. The infusion of these solvents leads to morphological changes in the gallbladder wall with some focal ulcerations. These alterations can be almost completely recovered after two weeks. No histologic evidence of hepatic, duodenal or renal damage was found. We conclude that the mixture methyl tert-butyl ether/dimethylsulfoxide (70/30) constitutes a good solvent for mixed cholesterol stones. Compared with pure methyl tert-butyl ether, the mixed system allows for a more rapid and a more complete dissolution of gallstones.  相似文献   
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