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81.
血管内支架在冠状动脉复杂病变成形术中的临床应用   总被引:1,自引:0,他引:1  
目的探讨血管内支架在冠状动脉复杂病变成形术中的应用效果及价值.方法对冠心病患者复杂冠状动脉病变在经皮穿刺冠状动脉成形术(PTCA)并发急性血管内闭塞、内膜严重撕裂、术后显著残留狭窄及短期内再狭窄等情况下进行了血管内支架植入术(CASI).结果31例患者CASI均获成功,术后急性血管闭塞和内膜撕裂征象消失,残留狭窄及再狭窄解除,未出现出血和穿刺部位血管并发症及CASI后亚急性血栓形成.随访16例,1例术后13天发生猝死;2例因胸痛复发经造影证实支架血管再狭窄,再次球囊扩张后再狭窄改善;余13例冠状动脉造影示支架血管正常.结论冠心病复杂冠状动脉病变行CASI是解除PTCA急性并发症的安全、有效和可行的方法,并有助于PTCA后再狭窄的防治.  相似文献   
82.
目的;比较不同方法切除胃肠道息肉和癌前病变的疗效。方法:本文采用高频电和其它不同方法对胃肠道息肉和癌前病变切除和切割。结果:对小的扁平息肉用高频电灼除或热活检安全有效。一次的灼除达100%。圈套适应胃结肠有蒂息肉。对大的有蒂或分叶状息肉需分次圈套切除,圈套和烧灼或热活检结合可避免肠穿孔发生。双胃镜代替双腔治疗胃镜行粘膜切除胃内平坦和扁平隆起性非典型增生灶操作容易,病灶切除彻底。息肉切除后常于局部形成溃疡,术后应常规给予酸抑制剂和粘膜保护剂治疗。结论:内镜-高频电是切除胃肠道有蒂和无蒂息肉的有效方法,粘膜染色后,双胃镜行粘膜和术治疗胃内癌前病变切实可行。  相似文献   
83.
食管粘膜活检取样误差的发生机制及对策   总被引:2,自引:0,他引:2  
目的:探讨食管粘膜活检取样误差的发生机制及对策。方法:对来自河南食管癌高发区28例患者行食管内镜检查和中、下段粘膜活检组织病理检查,10天短期随访后对同一人群作重复检查;并对88位无症状受检者进行碘染与活检相结合的方法。结果:第二次粘膜活检组织中,食管中段24%的患者病变减轻,28%的患者病变加重,48%的患者病变维持不变。食管下段粘膜活检中,48%的患者病变减轻,16%的患者病变加重,32%的患者病变维持不变;碘染受检者的食管粘膜中染色正常和染色异常的粘膜组织在癌前病变各阶段的构成比无明显差异。组织形态学测量显示:各级癌前组织与正常上皮组织的厚度无明显差异。结论:粘膜活检取样误差可严重影响组织病理学检查随访结果。食管粘膜癌前病变,特别是较轻度病变的厚度与同期正常上皮无明显改变,造成内镜下识别困难,是造成取样误差的重要因素。碘染可明显提高内镜下病变与同期正常组织的识别,但对小范围病变的活检准确度仍需改进。肿瘤抑制基因p53蛋白聚集的重复性检出率较高,可能是食管癌变过程中的有效指标。  相似文献   
84.
We studied invasion-related adhesion events in vitro using three squamous carcinoma cell lines (HSC-3, poorly differentiated type; OSC-19, well-differentiated type; and KB cells, undifferentiated type). An in vitro invasion assay through matrigel in the transwell chamber revealed that HSC-3 cells were most invasive, OSC-19 cells moderately invasive and KB cells least invasive. Inhibition assay of invasion using synthetic peptides RGD, RGDV, RGDS, RGDT, IKVAV and YIGSR, showed that invasion of the three cell lines was significantly inhibited by RGDV. There were other peptides that inhibited invasion significantly including IKVAV for HSC-3, and RGDS and YIGSR for OSC-19. HSC-3 cells and OSC-19 cells adhered to fibronectin, laminin, vitronectin, and type IV collagen, and KB cells did not adhere to laminin but did to fibronectin, vitronectin and collagen type IV. Pretreatment of cells with RGDV peptide in the attachment assay reduced the ability of these cells to bind to vitronectin and fibronectin more efficiently than pretreatment with RGDS. Anti-v antibodies inhibited adhesion of HSC-3, OSC-19 and KB cells to vitronectin, but anti-1 antibodies did not inhibit adhesion. Immunofluorescent microscopic examinations showed that all cell lines were positive for anti-5 and anti-v antibodies, and only HSC-3 cells were positive for anti-3 antibody. 51 was not clearly demonstrated in any of the cell lines. RGDV was the most effective inhibitor of squamous cell carcinoma invasion among the synthetic oligopeptides used in this experiment, and it is suggested that it affects v3-and/or v5-mediated carcinoma cell invasion.Abbreviations BSA bovine serum albumin - MEM Eagle's minimal essential medium - MTT 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide - PBS phosphatebuffered saline - FITC fluorescein isothiocyanate This work supported in part by a grant from the Osaka Cancer Research Foundation  相似文献   
85.
Objective. To assess the utility of MR in detecting surgically induced Stener lesions (displaced thumb ulnar collateral ligaments) in cadaveric models. Design. Six cadaver thumbs had ulnar collateral ligament (UCL) tears created surgically. MR examinations (2D STIR and 3D GRASS) were performed identically on all specimens both before displacement (non-Stener) and after displacement (Stener lesion) of the UCL. The MR images were then randomly numbered. Each image was evaluated separately in blinded fashion by four musculoskeletal radiologists for the presence or absence of a Stener lesion. Each radiologist reinterpreted the images after an interval of several days. The interpretation was based on previously published criteria for Stener lesion diagnosis by MR. Results. The sensitivity of GRASS ranged from 0.17 to 0.67 with the most experienced reader scoring the lowest. The specificity of GRASS ranged from 0.33 to 1.0 (most experienced reader 0.67, 0.83). STIR had a sensitivity of 0.00–0.17 and a specificity of 0.53–0.83. The values for inter- and intraobserver agreement were measured. The intraobserver for GRASS was 0.27–0.75 (most experienced reader 0.75). Conclusions. 2D imaging is probably inadequate for the evaluation of Stener lesions. The most likely reason is that the STIR slice thickness of 3 mm limits resolution of small UCLs. The poor sensitivity and specificity of GRASS as well as poor interobserver agreement suggest that MR may not be sufficiently accurate for Stener lesion evaluation.  相似文献   
86.
T-lymphocytes expressing T -cell receptors (TCRs) of the / type have been suggested to play an important role in mucosal defense against infection and neoplastic transformation. In this study, an immunohistochemical investigation was performed on the distribution of / and / TCRs among tumor-infiltrating lymphocytes. Thirteen patients with squamous cell carcinomas of the upper aerodigestive tract were studied, using monoclonal antibodies and an avidin-biotin-peroxidase technique. Most of the T-cells had an / TCR. Only 1.6% of the T-cells within the cancer tissue and 1.2% of the T-cells in the parenchyma adjacent to the cancer tissue expressed /gd TCRs. These results are consistent with the results of similar studies in bronchial and breast carcinomas. Biopsies from normal oral mucosa in nine healthy individuals showed that 1.3% of the T -cells within the epithelium and 1.0% of those in the lamina propria adjacent to the epithelium expressed / TCRs. Quantitatively the results do not support the theory that / T-cells play an important role in the immunological response against cancer tissue in the mucosa of the upper aerodigestive tract. The functional role of these cells in the mucosa and in response to carcinomas is, however, still uncertain.  相似文献   
87.
P^16基因蛋白在子宫颈鳞癌组织中的表达   总被引:3,自引:1,他引:2  
应用免疫组织化学方法对58例子宫颈鳞状上皮细胞癌及5例宫颈上皮内瘤样病变标本的P^16基因表达进行研究,取8例正常子宫颈组织作对照,结果显示:P16基因的阳性表达率在宫颈鳞癌,宫颈上此内瘤样病谱及正常宫颈组织中分别为43.1%,40%,12.5%,肿瘤病理分级越低,临床分期越晚,阳性表达率越低,差异有显著性(P<0.05),提示:P16基因的异常表达在子宫颈鳞癌的发生,发展过程中起重要作用。  相似文献   
88.
89.
目的 探讨门脉高压状态下脾脏的功能及其在门脉高压发展中的作用。方法 研究28 例门脉高压症患者和10 例外伤性脾破裂患者脾脏的血管病变,采用常规HE 染色和MASSON 三色染色,光镜下观察其血管的病理改变。结果 与外伤性脾破裂脾脏比较,门脉高压脾内血管发生多种改变如:硬化性血管内膜炎病变,均发生内皮细胞受损、胶原纤维细胞外基质增多、弹力纤维断裂和管壁纤维化。结论 ①门脉高压时脾脏微循环发生改变,免疫功能处于紊乱状态;存在保脾和切脾的争论的主要原因是脾脏的病理进展时期不一致;②脾脏在尤其是中重度门脉高压发展中起促进作用;脾内血管病变是门静脉高压症血管病变的一部分  相似文献   
90.
Oh JD  Vaughan CL  Chase TN 《Brain research》1999,821(2):433-442
Sensitization of striatal N-methyl-d-aspartate (NMDA) receptors has been implicated in the pathogenesis of the response alterations associated with dopaminomimetic treatment of parkinsonian animals and patients. To determine whether serine phosphorylation of NMDA receptor subunits by activation of Ca2+/calmodulin-dependent protein-kinase II (CaMKII) contributes to this process, we examined the effects of unilateral nigrostriatal ablation with 6-hydroxydopamine and subsequent treatment with levodopa, SKF 38393 (D1-preferring dopamine agonist), or quinpirole (D2-preferring agonist) on motor responses and phosphorylation states. Three weeks of twice-daily levodopa administration to rats shortened the duration of their rotational response to levodopa or SKF 38393 challenge, but prolonged the duration of quinpirole-induced rotation. At the same time, levodopa treatment elevated serine phosphorylation of striatal NR2A (p<0.02), but not that of NR2B subunits, without associated changes in subunit protein levels. Chronic treatment with SKF 38393 increased NR2A (p<0.0001) but decreased NR2B (p<0.004) serine phosphorylation. In contrast, chronic quinpirole treatment had no effect on NR2A but increased NR2B phosphorylation (p<0.0001). The acute intrastriatal injection of the CaMKII inhibitor KN93 (1.0 micrograms) not only normalized the levodopa-induced motor response alterations but also attenuated the D1 and D2 receptor-mediated serine phosphorylation of NR2A and NR2B subunits, respectively (p<0.02). These results suggest that a CaMKII-mediated rise in serine phosphorylation of NMDA receptor subunits induced by intermittent stimulation of D1 or D2 dopaminergic receptors contributes to the apparent enhancement in striatal NMDA receptor sensitivity and thus to the dopaminergic response plasticity in levodopa-treated parkinsonian rats.  相似文献   
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