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131.
大鼠下丘脑一氧化氮合酶(NOS)阳性神经元的分布   总被引:3,自引:0,他引:3  
观察大鼠下丘脑各核团NOS阳性神经元的分布。采用还原型尼克酰胺腺嘌呤二核苷酸脱氢酶(NADPH-d)法,结果显示,大量NOS阳性神经元见于下丘脑外侧区、视上核(SO)和室旁核(Pa);出现较多NOS阳性神经元的部位是视前大细胞核,见到少量NOS阳性神经元的部位是室周核、视前内侧区、视前外侧区和下丘脑前区。结论:NOS阳性神经元分布于下丘脑的许多核团。  相似文献   
132.
西藏大骨节病患者血清Se与几种细胞因子含量的变化   总被引:2,自引:0,他引:2  
目的:测定大骨节病患者和正常对照血清中硒和肿瘤坏死因子-α(TNF-α)、血管内皮生长因子(VEGF)和白介素-1(IL-1β)的水平。从细胞因子角度为研究其发病机制提供实验依据。方法:在西藏拉萨尼木县和墨竹工卡县的大骨节病区随机选取大骨节病患者30例(患者组),病区正常人30例(病区内对照组),在拉萨非大骨节病区选健康志愿者30例(病区外对照组),3组人群年龄和性别没有显著性差异。采取静脉血离心制备血清。采用荧光法测定血清Se,酶联免疫吸附测定法(ELISA)检测血清中细胞因子水平。结果:西藏大骨节病病区患者和正常人血清中Se低于非大骨节病区正常人;患者血清中TNF-α、VEGF和IL-1β的水平高于正常。血清Se与TNF-α、IL-1β水平呈负相关趋势。结论:低硒和血清中细胞因子水平升高在KBD的发病过程中起着某种作用。  相似文献   
133.
甲壳素短纤维增强聚己内酯复合材料的制备及生物学评价   总被引:1,自引:0,他引:1  
用共混法制备甲壳察短纤维增强聚己内酯复合材料,并对纯聚己内酯和甲壳察短纤维增强聚己内酯复合材料进行体外细胞毒性和生物相容性评价,为临床应用提供有价值的实验依据。对该两种材料进行体外细胞毒性试验、急性全身毒性试验、溶血试验、热源试验和过敏试验。结果显示受试材料最终细胞毒性级为0级,对细胞生长和增殖无明显抑制作用,材料中不存在潜在致敏性物质,浸提液无溶血反应和急性全身毒性反应,无热源反应,表明该复合材料具有良好的细胞和组织相容性,其作为胸壁缺损修补材料应用于临床具有可行性和安全性。  相似文献   
134.
用婴幼儿轮状病毒抗原免疫产卵母鸡,制备出抗婴幼儿轮状病毒鸡卵黄免疫球蛋白(抗-HRVIgY)同时研究抗-HRVIgY的抗人类胃酸屏障能力,抗消化道蛋白酶的酶解以及临床使用的安全性和效果,研究结果表明:抗-HRVIgY具有一定的抗胃酸屏障能力和抗消化道蛋白酶酶解作用,抗-HRVIgY安全无毒,对婴幼儿轮状病毒感染具有被动免疫保护作用。  相似文献   
135.
评价用聚乙二醇系列的表面改性剂PEG、F127及PELA改性的纳米羟基磷灰石/聚乳酸复合材料的亲水性和溶胀性,先对纳米羟基磷灰石进行表面改性处理后,再综合用传统的溶液共混、流延法及热压法将改性的和未改性的纳米羟基磷灰石分别与聚乳酸制备成复合薄膜。检测结果表明:改性剂分别被涂敷于纳米羟基磷灰石上,改性处理能够改善纳米颗粒在基材内的分布;改性的纳米羟基磷灰石/聚乳酸复合材料比未改性的对比材料的表面接触角小、表面能大、亲水性好、溶胀度大,达到饱和溶胀度的时间长。改性的纳米羟基磷灰石比未改性的羟基磷灰石改善基体聚乳酸的亲水性和溶胀性效果更显著。  相似文献   
136.
目的探讨距骨颈骨折治疗方案的选择以及疗效相关因素分析。方法距骨颈骨折15例,男13例,女2例。年龄16~63岁,平均40.5岁,合并腰椎、髋臼、跟骨、外踝骨折各1例。开放骨折2例。陈旧性骨折2例(〉1个月)。按Hawkins骨折分类:Ⅰ型3例、Ⅱ型9例、Ⅲ型3例。Ⅰ型骨折采用膝下管型石膏固定,其中1例复诊中因移位行切开复位松质骨螺钉固定。Ⅱ型骨折均行切开复位,克氏针或松质骨螺钉固定。Ⅲ型骨折1例开放性骨折,急诊行清创缝合,手法+撬拔复位,脱位整复。一周后在C臂机引导下,采用二枚直径4.0mm中空螺钉由后向前固定距骨颈,1例急诊手术切开复位,克氏针内固定。结果本组13例获得随访,时间4~24个月,平均12.3个月。13例中发生距骨体缺血性坏死5例,其中Ⅱ型骨折4例,Ⅲ型骨折1例。另2例未统计在内。1例外院病例术后并发伤口感染长期不愈,行小腿截肢术。1例患者拒绝手术治疗。按Hawkims疗效标准,优4例,良4例,可3例,差2例,优良率69%。结论对无移位的距骨颈骨折,行膝下管型石膏固定6~12周,并定期拍片复查,距骨颈骨折脱位应急诊复位和可靠的内固定。以2枚拉力螺钉内固定为宜,尽量减少并发症。对距骨体缺血性坏死,或创伤性关节炎,则根据患者的实际情况采取相应治疗措施。  相似文献   
137.
Endoglin (CD105) has been shown to be a more useful marker to identify proliferating endothelium involved in tumor angiogenesis than panendothelial markers such as CD31. We investigated endoglin and vascular endothelial growth factor expression as possible prognostic markers in colorectal cancer. Surgical specimens from 150 patients with resected colorectal carcinomas were immunostained for endoglin, CD31 and vascular endothelial growth factor. Colorectal carcinoma cases consisted of 50 cases without lymph node metastases, 50 cases with only lymph node metastases and 50 cases with liver metastases (38 cases also had positive lymph nodes). Positively stained microvessels were counted in densely vascular foci (hot spots) at x 400 fields in each specimen. For vascular endothelial growth factor, intensity of staining was scored on a three-tiered scale. Results were correlated with other prognostic parameters. Endoglin demonstrated significantly more proliferating neoplastic microvessels than CD31 (31+/-10 vs 19+/-8/0.15 mm2 field, P<0.001). Low vascular endothelial growth factor expression within tumor cells was seen in 49 (33%) and high expression in 101 cases (67%). There was a positive correlation of endoglin, CD31 counts and vascular endothelial growth factor overexpression with the presence of angiolymphatic invasion and lymph node metastases (P<0.05). Only endoglin counts correlated significantly with liver metastases and positive vascular pedicle lymph nodes (P<0.05), while vascular endothelial growth factor showed significant correlation with the depth of invasion (P<0.01). Endoglin, by staining higher numbers of the proliferating vessels in colon carcinoma, is a more specific and sensitive marker for tumor angiogenesis than the commonly used panendothelial markers. Endoglin staining also showed prognostic significance with positive correlation with angiolymphatic invasion and metastases to lymph nodes and liver.  相似文献   
138.
A chromatographic method, which can quantitate mitomycin C (MMC) along with two antiglaucoma drugs, is described. The separation of MMC, alphagan and timolol was performed on a reversed-phase C18 column with water-methanol-trifluoroacetic acid (65:35:0.01, v/v) as the mobile phase. By monitoring at 360, 248 and 296 nm, the lower limits of detection for MMC, alphagan and timolol are, respectively, 1.0, 2.0 and 5.0 ng (injection amount) at three-time S/N ratio. The dynamic ranges of quantitation for the three drugs are, respectively, 1.0 ng-10.0 microg, 2.0 ng-10.0 microg and 5.0 ng-10.0 microg with linearity being larger than 0.9960. This method was applied to the determination of MMC levels in Tenon's and trabeculum tissues of 10 glaucoma patients. MMC levels in these tissues, which were obtained from glaucoma filtering surgery, were determined following a multiple extraction with methanol. The recovery of MMC for a two-batch extraction was better than 91.2%. The reproducibility of measurement for the MMC levels in these tissues is 2.5-6.0% RSD for triplicate injections. The intra-day variation of retention times for the MMC peaks was less than 1.6% RSD (n=3). The inter-day variation of retention times for the MMC peaks was less than 4.8% RSD (n=3). MMC was detectable in three trabeculum tissues out of 10 cases (ranging from 0.8 to 25.5 ng/mg specimen), while MMC was detected in nine Tenon's tissues out of 10 cases (ranging from 0.3 to 21.1 ng/mg specimen). The results obtained show that the method is sensitive and selective for the quantitation of MMC.  相似文献   
139.
The interaction of T cell CD28/CTLA-4 receptors with B7 on antigen-presenting cells (APCs) represents an important co-stimulatory pathway in T cell activation or anergy. Our previous study indicated that recipients immunized with allogenic donor immature dendritic cells (DCs) or resting B cells could induce specific immune tolerance and prolong allograft survival. A possible mechanism for this observation is that the expression of B7 molecules is either at a low level or lacking on these cells. The present study investigates whether blockade of B7 molecules on donor splenocytes with a B7 antisense peptide (B7AP), i.e. a peptide analogue of the CD28-binding region, could induce specific immune tolerance and prolong allograft survival in the recipients. Both the lymphocyte proliferation reaction and the mice pinna cardiac allograft experiment were performed to evaluate the role of B7AP in inducing specific immune tolerance in recipients in vitro and in vivo. The results showed that 56.65% and 20.52% of C57BL/6 splenocytes expressed B7.1 and B7.2 molecules, respectively, on their cell surface. There were no significant changes of the B7 expression on such splenocytes after being treated by the B7AP (53.28% and 19.06%, respectively). B7AP inhibited the mixed lymphocyte reaction by up to 38.4% and a dose-response correlation was observed for inhibition. The recipients (BALB/c) immunized with B7AP-pretreated C57BL/6 splenocytes induced a specific immune hypo-response (43%versus control) and notably prolonged survival of the C57BL/6 cardiac allograft by up to 20.3 days. In contrast to the normal saline group (average: 8.6 days) and FTD(10) control peptide group (<4 days), the cardiac allograft survival of the test group was extended for an additional 11.7 days. These results strongly support the notion that immunization with donor splenocytes, which had been pretreated with B7AP, induced specific immune tolerance and prolonged allograft survival in the recipients.  相似文献   
140.
胡继军  方向明  陈晓红  熊碧芳  柳亢宗 《微循环学杂志》2005,15(3):38-40,F0006,F0009
目的:研究血清中血管内皮生长因子(VEGF)和一氧化氮(NO)表达水平及其与大肠癌恶变程度的关系。方法:分别采用酶联免疫吸附法(ELISA)测定和分光光度法检测46例大肠癌患者术前和30例健康人血清中VEGF和NO的含量。结果:大肠癌患者血清VEGF和NO表达水平均较健康人明显增高(P<0.01),且随着大肠癌浸润深度增加、有淋巴结转移以及Dukes分期愈晚者而显著增高(P<0.01)。血清VEGF与NO含量呈明显正相关(r=0.8152,P<0.01)。结论:VEGF和NO与大肠癌的发生、发展及转移调控过程有关,术前检测血清VEGF和NO含量对判断大肠癌的浸润转移以及Dukes分期具有重要价值。  相似文献   
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