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91.
92.
There is a lack of studies on somatic gene mutations and cell signaling driving penile carcinogenesis. Our objective was to analyze somatic mutations in genes downstream of EGFR in penile squamous cell carcinomas, especially the mTOR and RAS/MAPK pathways. We retrospectively analyzed somatic mutations in 10 in situ and 65 invasive penile squamous cell carcinomas by using Sequenom's Mass Spectrometry iPlex Technology and Oncocarta v1.0 Panel. The DNA was extracted from FFPE blocks and we identified somatic missense mutations in three in situ tumors and in 19 invasive tumors, mostly in PIK3CA, KRAS, HRAS, NRAS, and PDGFA genes. Somatic mutations in the PIK3CA gene or RAS family genes were neither associated with tumor grade, stage or outcome, and were equally often identified in hrHPV positive and in hrHPV negative tumors that showed no p53 expression. Mutations in PIK3CA, KRAS, and HRAS are frequent in penile squamous cell carcinoma and likely play a role in the development of p53‐negative tumors. Although the presence of these mutations does not seem to correlate with tumoral behavior or outcome, they could be biomarkers of treatment failure with anti‐EGFR mAb in patients with penile squamous cell carcinoma. © 2015 Wiley Periodicals, Inc.  相似文献   
93.
Lower urinary tract dysfunctions (LUTD) restrict quality of life, resulting in decreased work productivity and emotional well‐being. However, most people are not diagnosed because they do not seek medical treatment. In addition, some facilities do not adequately train health professionals in the evaluation, diagnosis and treatment of these conditions. The study's objective was to develop a decision support system modelled on fuzzy logic that defines LUTD using the terminology of the International Continence Society. This methodological study aimed to develop a model that uses the maximum–minimum composition (max–min) of fuzzy relations that can perform differential diagnoses of LUTD. The model was tested in 100 cases (50 men and 50 women), and the data were obtained from medical records containing the clinical data and results of urodynamic studies. All medical records were reviewed by a specialist in urology. The model was capable of determining a diagnosis in full (62%) or partial (36%) agreement with the medical report. Agreement between the model and the medical report was excellent (kappa = 0·98, p ? 0·001, CI = 0·88–1) or substantial (kappa = 0·53, p ? 0·001, CI = 0·45–0·60), considering overestimative accordance (where accordance is assumed when at least one diagnosis is equal) and underestimative accordance (where accordance is assumed when all diagnoses are equal), respectively. The proposed model based on the max–min composition of fuzzy relationships is very simple and performed well. However, more tests are recommended before the model is used as a decision support system.  相似文献   
94.
Preventing falls and fall-related fractures in the elderly is an objective yet to be reached. There is increasing evidence that a supplementation of vitamin D and/or of calcium may reduce the fall and fracture rates. A vitamin D-calcium supplement appears to have a high potential due to its simple application and its low cost. However, published studies have shown conflicting results as some studies failed to show any effect, while others reported a significant decrease of falls and fractures. Through a 15-year literature overview, and after a brief reminder on mechanism of falls in older adults, we reported evidences for a vitamin D action on postural adaptations - i.e., muscles and central nervous system - which may explain the decreased fall and bone fracture rates and we underlined the reasons for differences and controversies between published data. Vitamin D supplementation should thus be integrated into primary and secondary fall prevention strategies in older adults.  相似文献   
95.
目的:通过细胞形态学观察及生物学特性鉴定,建立一种经济实用的体外原代培养纯化新生鼠嗅鞘细胞的实验方法。方法:实验于2006-06在武汉理工大学完成。①阿糖胞苷(Sigma,批号w10562);胎牛血清(杭州四季青产品);胰蛋白酶(Amresco);多聚赖氨酸(Sigma);胶质纤维酸性蛋白,神经生长因子受体蛋白抗体(博士德)。②选取出生3d内的Wistar大鼠5只,乙醇浸泡后断头处死,取嗅球的最外两层,通过1.25g/L胰蛋白酶消化分离嗅鞘细胞,体外原代培养。③采用Nash差速贴壁 阿糖胞苷 胰酶法纯化嗅鞘细胞。培养18h后将未贴壁的细胞悬液转种于另一未涂层的器皿中,再培养36h,重复上述步骤移入0.1g/L多聚赖氨酸包被的塑料培养瓶中进行培养,纯化后的细胞在24h内陆续贴壁,常规培养2d,加入终浓度为2mg/L的阿糖胞苷,作用48h后,换上新的培养基,继续培养1d,弃去培养基,用无钙镁的Hanks液清洗2次,然后用1.25g/L的胰酶消化10min,待细胞突起回缩、胞体变圆时,立刻加入纯血清终止,其血清终浓度为20%,制备单细胞悬液。④倒置显微镜下观察其形态变化,苏木精-伊红染色,同时行神经生长因子受体蛋白和胶质纤维酸性蛋白免疫组化染色鉴定嗅鞘细胞,并计算嗅鞘细胞阳性百分率。结果:①活细胞形态观察:分离培养的嗅鞘细胞具有双极或多极突起,且突起细长,相互交织。②嗅鞘细胞的苏木精-伊红染色鉴定:细胞呈三角形或梭形,有长的突起,胞浆被染成粉红色,胞核呈蓝紫色,胞核内深染的为核仁,有1~3个核仁。③嗅鞘细胞的胶质纤维酸性蛋白免疫组化染色鉴定:细胞呈现棕黄色,胞核淡染,阳性细胞成网状连接,胞体多为三角形,有细长突起,阳性率91.5%。④嗅鞘细胞的P75免疫组化染色鉴定:阳性细胞呈绿色,多数细胞染色阳性,阳性率89%。结论:实验所采用的Nash差速贴壁 阿糖胞苷 胰酶法分离纯化培养嗅鞘细胞切实可行,为神经诱导修复材料的研究提供种子细胞。  相似文献   
96.
目的:观察认知矫正治疗对慢性精神分裂症患者临床症状和社会功能的改善作用。方法:选择2003-01/08在北京回龙观医院住院的慢性精神分裂症患者104例。均符合CCMD-Ⅲ及DSM-Ⅳ关于精神分裂症诊断标准;年龄25~55岁;病程≥2年;病情稳定,处于迁延、残留或部分缓解状态;药物治疗状况稳定,近期无换药打算;纳入对象或家属同意入组并签署知情同意书。应用随机数字表法将患者分认知矫正治疗组和对照组,每组52例。在相近药物治疗的基础上,认知矫正治疗组以Ann Delahunty和Rodney Morice等制定的神经认知矫正手册(汉化)为治疗工具,在治疗师的指导下进行认知作业练习,内容包括认知灵活性、工作记忆、计划执行功能3大功能模块。对照组予以相同时间的工娱治疗,主要包括有治疗师指导的操作性音乐治疗和舞蹈治疗。治疗前后两组患者分别进行PANSS、住院精神患者社会功能缺陷量表和护士观察量表的评定。结果:实验共纳入慢性精神分裂症患者104例,认知矫正治疗组44例,对照组46例进入结果分析,14例脱落。①治疗前后两组患者PANSS量表总分以及阴性症状量表、复合量表、一般精神病理量表、反应缺乏量表4个分量表的评分均有下降,组内比较差异有显著性意义(t=2.12~4.59,P<0.05);减分情况在两组间差异不明显(P>0.05)。②两组患者的社会功能缺陷量表总分在治疗后均有下降,与治疗前比较,差异有显著性意义(t=3.89,2.04,P<0.05);两组间比较,差异无显著性意义(P>0.05)。认知矫正治疗组治疗后护士观察量表的总病情以及总消极、迟滞2个分量表评分下降,与治疗前比较差异有显著性意义(t=1.49,1.19,2.81,P<0.05);其中迟滞项的减分在两组间比较,差异具有显著性意义(F=4.97,P<0.05)。③社会功能量表的改善与词语流畅性的改善呈正相关(R2=0.36,P<0.05),护士观察量表中总病情与积极两项评分的改善也与言语流畅性测验的改善正相关(R2=0.37,0.34,P<0.05)。结论:认知矫正治疗能在一定程度上改善精神分裂症患者的社会功能,并与部分认知功能的改善相关,但对临床症状无明显改善作用。  相似文献   
97.
MAP17 enhances the malignant behavior of tumor cells through ROS increase   总被引:1,自引:0,他引:1  
Tumorigenesis occurs when the mechanisms involved in the controlof tissue homeostasis are disrupted and cells stop respondingto physiological signals. Therefore, genes capable of desensitizingtumoral cells from physiological signals may provide a selectiveadvantage within the tumoral mass and influence the outcomeof the disease. We undertook a large-scale genetic screen toidentify genes able to alter the cellular response to physiologicalsignals and provide selective advantage once tumorigenesis hasbegun. We identified MAP17, a small 17 kDa non-glycosylatedmembrane protein previously identified by differential displaybeing over-expressed in carcinomas. Tumor cells that over-expressMAP17 show an increased tumoral phenotype with enhanced proliferativecapabilities both in presence or absence of contact inhibition,decreased apoptotic sensitivity and increased migration. MAP17-expressingclones also grow better in nude mice. The increased malignantcell behavior induced by MAP17 are associated with an increasein reactive oxygen species (ROS) production, and the treatmentof MAP17-expressing cells with antioxidants results in a reductionin the tumorigenic properties of these cells. Treatment of melanomacells with inhibitors of Na+-coupled co-transporters lead toan inhibition of ROS increase and a decrease in the malignantcell behavior in MAP17-expressing clones. Finally, we show thatMAP17-dependent ROS increase and tumorigenesis are dependenton its PDZ-binding domain, since disruption of its sequenceby point mutations abolishes its ability to enhance ROS productionand tumorigenesis. Our work shows the tumorigenic capabilityof MAP17 through a connection between Na+-coupled co-transportersand ROS. Abbreviations: FBS, fetal bovine serum; DMEM, Dulbecco's modified Eagle's medium; PBS, phosphate-buffered saline; ROS, reactive oxygen species; MAP17, membrane associated protein 17 kDa Received March 27, 2007; revised May 8, 2007; accepted May 14, 2007.  相似文献   
98.
Aim of the studyTo correlate hepatitis A virus cellular receptor (HAVCR)/kidney injury molecule-1 (KIM-1) expression in clear cell renal cell carcinoma (ccRCC) tumours with patient outcome and study the consequences of HAVCR/KIM-1 ectodomain shedding.MethodsHAVCR/KIM-1 expression in ccRCC, oncocytomes, papillary carcinomas and unaffected tissue counterparts was evaluated. Minimal change disease and pre-clamping normal and ccRCC tissue biopsies were included. Tissue microarrays from 98 ccRCC tumours were analysed. Tumour registry data and patient outcome were retrospectivelly collected. Deletions in HAVCR/KIM-1 ectodomain and lentiviral infection of 786-O cells with HAVCR/KIM-1 mutated constructs to determine their subcellular distribution and invasive capacity were performed.ResultsHAVCR/KIM-1 was expressed in ccRCC, papillary tumours and in tubule cells of adjacent and distal unaffected counterparts of ccRCC tumours. The latest was not related to ischemic or tumour-related paracrine effects since pre-clamping normal biopsies were positive for HAVCR/KIM-1 and unaffected counterparts of papillary tumours were negative. HAVCR/KIM-1 analyses in patients and the invasive capacity of HAVCR/KIM-1 shedding mutants in cell lines demonstrated that: (i) relative low HAVCR/KIM-1 membrane levels correlate with activated shedding in ccRCC patients and mutant cell lines; (ii) augmented shedding directly correlates with higher invasiveness and tumour malignancy.Concluding statementsConstitutive expression of HAVCR/KIM-1 in kidney might constitute a susceptibility trait for ccRCC tumour development. Enhanced HAVCR/KIM-1 ectodomain shedding promotes invasive phenotype in vitro and more aggressive tumours in vivo.  相似文献   
99.
We describe the prenatal diagnosis of a true knot of the umbilical cord using the "hanging noose" sign. Changes in the tension of the knot, which are related to fetal movements, were studied with 4-dimensional ultrasonography.  相似文献   
100.
Response to chemotherapeutic agents in malignant tumors depends on many factors, most of which are as yet unknown. We investigated the correlation between the activation of different oncogenes and protein-kinase-C(PKC) modulation, and the cytotoxicity of some of the most widely used anti-cancer drugs. We transformed the murine keratinocyte cell line PAM 212, with different oncogenes (v-H-ras, v-myc and adenovirus El a) and a mutant p53 suppressor gene (mp53). The cytotoxic effect of cisplatin (CDDP), doxorubicin(DOX) and vincristine (VCR), together with the concomitant action of modulators of PKC, TPA and staurosporine were evaluated by the crystal-violet method, thymidine incorporation and flow cytometry. We report that (a) the oncogene v-H-ras induces resistance to CDDP (> 50%), DOX (> 25%) and VCR (> 20%); (b) the E l a oncogene induces only resistance to VCR (>40%) and marked sensitivity to CDDP and DOX; (c) the mp53 oncogene induces more resistance to VCR and insignificant resistance to the other drugs; and (d) activation of PKC by TPA increases the resistance to VCR and DOX in cells transformed by the v-H-ras, while it significantly increases the lethality with CDDP of the E l a-transformed cells. Staurosporine increases the cytoxicity of all the drugs, especially in the E l a-transformed keratinocytes. In the flow-cytometry analysis, the percentage of BUdR incorporation was related to sensitivity to anti-cancer drugs. © 1995 Wiley-Liss, Inc.  相似文献   
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