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91.
目的探讨通过椎弓根的投影法植入椎弓根螺钉的可行性及临床应用价值。方法通过对椎弓根的解剖及椎弓根投影的影像解剖研究,探讨通过椎弓根投影植入椎弓根螺钉的可行性,临床上前瞻性地利用该法植入胸椎椎弓根螺钉50枚,腰椎椎弓根86枚,术后CT复查。胸椎植入的成功率与经典Margel法对比,腰椎植入的成功率与经典的AO法对比,利用SPSS13.0的Pearson Chi-Squaretest对结果进行统计分析,分析该法与AO及Margel法的成功率是否存在显著差异。结果椎弓根的投影就是椎弓根行径在X线片及CT片上的投影,临床利用椎弓根的投影法植入胸椎螺钉16例50枚,Margel法31例74枚,投影法植入腰椎螺钉23例86枚,AO法32例142枚,投影法胸椎的成功率明显高于Margel法,腰椎的成功率与AO法没有明显的显著性差异。结论椎弓根投影法植入螺钉的方法是可靠、可行的。  相似文献   
92.
学生课堂教学质量评价问题浅析   总被引:1,自引:0,他引:1  
综合分析河南中医学院近三年以来学生课堂教学质量评价反馈的信息,认为引发课堂教学评价偏差的人为因素有评价者的能力水平、责任心、情感倾向。其对策为:改变教师的被动地位,进一步修订评价体系,加强对组织评价者的培训,强化临床课的教学,进一步提高学生的认识,跟踪调查课堂教学质量评价。  相似文献   
93.
The aim of this study was to clarify and compare the temporal course of bone mineral density (BMD) between fast bone losers and normal residents in Miyama Village, a rural Japanese community. BMD was measured over a 10-year period in a cohort study in Miyama Village, Wakayama Prefecture, Japan, to provide information on rate of bone loss in the mature and elderly population. Subjects (n=400) were selected by sex and age stratum from the full list of residents born in 1910–1949, with 50 men and 50 women in each age decade. Baseline BMD of the lumbar spine and proximal femur was measured using dual energy X-ray absorptiometry in 1990, 1993, 1997 and 2000. In the cohort, 171 men and 189 women completed the follow-up survey performed in 1993. After calculating the rate of bone loss between 1990 and 1993, the greatest tertile from the distribution of bone loss was categorized as fast bone losers, with the remainder considered as normal subjects. Changes in BMD were compared between normal subjects and fast bone losers over the 10-year period. Mean rate of change for BMD at both lumbar spine and femoral neck in fast bone losers recovered to levels similar to those in normal subjects over 7 years of observation. By contrast, BMD at the lumbar spine and femoral neck decreased steeply over the 10-year period in both groups, and mean BMD for fast bone losers was significantly lower than that of normal subjects (P<0.05). These differences were apparent only at the lumbar spine in both men and women, even after adjusting for age. These results indicate that fast bone loss is a transient phenomenon rather than a fixed status, although individuals who have been categorized as fast bone losers at some stage continue to display low BMD in the lumbar spine.  相似文献   
94.
目的研究17β-雌二醇(17β-E2)对子宫内膜异位症(内异症)患者在位子宫内膜间质细胞β-catenin mRNA和蛋白表达的影响,探讨Wnt/β-catenin信号通路在介导雌激素促进内异症发生发展的作用。方法体外分离培养内异症患者在位子宫内膜间质细胞。用不同浓度17β-E2处理子宫内膜间质细胞48 h;此后选用10-10mol/L 17β-E2处理子宫内膜间质细胞12、24和48 h,逆转录聚合酶链反应(RT-PCR)和免疫印迹法(Western blotting)检测17β-E2处理前后子宫内膜间质细胞β-catenin mRNA和蛋白的表达水平。同法分析雌激素受体拮抗剂ICI182,780(10-6mol/L)对17β-E2促进β-catenin mRNA和蛋白表达的影响。免疫组织化学染色观察17β-E2作用后β-catenin在子宫内膜间质细胞中的定位。结果17β-E2能明显促进内异症患者在位子宫内膜间质细胞β-catenin mRNA和蛋白的表达,并呈剂量和时间依赖性,于10-10mol/L作用48 h最明显。雌激素受体拮抗剂ICI182,780能明显抑制17β-E2对子宫内膜间质细胞β-catenin mRNA和蛋白的表达。免疫组织化学染色发现17β-E2能促进β-catenin在子宫内膜间质细胞核内的表达。结论雌激素可能通过激活Wnt/β-catenin信号通路促进内异症在位子宫内膜的异位种植。  相似文献   
95.
树舌多糖GF对小鼠HepA瘤基因组DNA甲基化影响的实验研究   总被引:2,自引:0,他引:2  
目的初步探讨树舌多糖GF对小鼠HepA瘤基因组甲基化的影响.方法提取基因组DNA,采用限制性酶切片段长度多态性分析的方法进行甲基化检测.结果 HpaII酶切结果:树舌多糖组可见3个条带,猪苓对照组可见3个条带, 阴性对照组可见4个条带,正常对照组可见2个条带.MspI酶切结果:树舌多糖组可见6个条带,猪苓对照组可见5个条带,阴性对照组可见5个条带,正常对照组可见6个条带.结论小鼠HepA瘤基因组DNA是低甲基化的,树舌多糖GF有阻碍小鼠HepA瘤基因组DNA低甲基化发生的趋势,可能还具有抗5mC的突变的作用.  相似文献   
96.
目的:从循证医学的角度解析炎性肠病药物治疗的相关进展。旨在提高对临床证据的认知,帮助临床医生评估新的治疗,从批判的视角重新看待以往的治疗。方法:收集国外近期相关文献进行评价。结果及结论:炎性肠病(IBD)的发病机制尚不清楚,众多的治疗方案可供选择。因此,循证医学研究结果有非常重要的临床指导意义。IBD的研究方面取得了可喜的进步。但是,有关CD活动指数(CDAI)和临床分型系统仍有待于改进。通过循证医学的研究证据有望确定安全和易于耐受的药物,并能发现目前诊治方面存在的缺陷和问题,更好地解决患者的病痛。  相似文献   
97.
98.
AIM: To evaluate in a prospective multicenter study the efficacy and safety of the suburethral support Uretex (Sofradim, Trevoux, France) delivered by a suprapubic approach in the treatment of female stress urinary incontinence. METHODS: Between March 2002 and March 2003, 57 patients were treated for stress urinary incontinence with Uretex. Preoperative evaluation included urodynamic examination and questionnaires (symptoms and quality of life, Contilife). Forty patients had pure stress urinary incontinence and 17 mixed urinary incontinence. No associated procedure was performed. The objective cure rate was evaluated by clinical examination and pad-test, and the subjective cure rate was assessed through questionnaires at 1, 3 and 12 months. RESULTS: The mean follow-up was 13 months (range 11-24 months). During follow up, chronic urinary retention requiring a tape section occurred in one patient, and in another patient a delay of vaginal healing was followed by a sling exposure and resection at 4 months. No infection or urethral erosion was reported. The objective cure rate was 96.2%, and the subjective cure rate was 79.2%; four patients reported low leakage on stress and nine patients complained of urge incontinence (four de novo and five persistent). CONCLUSION: The suprapubic Uretex Sup procedure is a safe and effective treatment for women with stress urinary incontinence.  相似文献   
99.
OBJECTIVE: Tumors arising within augmentation cystoplasties are aggressive, have poor prognosis and the majority are not detected at follow-up cystoscopy. Genetic changes in tumors precede morphological abnormalities. Therefore, the aim of this study was to investigate whether genetic abnormalities detected by comparative genomic hybridization (CGH) could be used to identify those patients with augmentation cystoplasties at increased risk of tumorigenesis. METHODS: Bladder biopsy samples were obtained from 16 augmentation cystoplasty patients both distant from and near to the enterovesical anastomosis. CGH was used to detect genetic abnormalities in DNA extracted from the biopsies, archival specimens of two augmentation cystoplasties and two de novo bladder adenocarcinomas. RESULTS: A greater number of amplifications on 2p, 3q, 8q, 9p, 17p, 18pq and 20pq, were observed in bladder biopsies obtained near to the enterovesical anastomosis compared to those taken distant to the suture line. CGH of archival augmentation cystoplasty tumor DNA indicated abnormalities at several loci with amplifications at 2q, 5q, 10p and 21pq, while deletions occurred at 5p and 16p. CONCLUSIONS: The results of this study suggest that the urothelium adjacent to the bladder and/or bowel anastomosis in augmentation cystoplasties is genetically unstable. Furthermore, longitudinal studies are required to establish whether or not patients exhibiting genetic instability following augmentation cystoplasty are at greater risk of developing tumors than those with genetically stable epithelia.  相似文献   
100.
A case of ultrastructurally confirmed myoepithelioma of the breast studied by fine-needle aspiration biopsy is reported. Aspirated tumor cells were spindle-shaped with well-defined cytoplasm and oval nuclei showing no remarkable nuclear pleomorphism. They were seen mainly in irregular bundles with strong cellular cohesiveness. Their cytoplasm contained S-100 protein demonstrated by the peroxidase antiperoxidase staining technique.  相似文献   
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