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91.
BackgroundThe association between hypertension and melanoma is unclear, and previous analyses of data from the ASPirin in Reducing Events in the Elderly (ASPREE) study demonstrated a reduced number of invasive melanoma events amongst aspirin-exposed hypertensive individuals.MethodsData from the ASPREE study which included (1) the intervention period with a median follow-up of 4.7 years, and (2) the observational period with an additional 2 years follow-up, were combined for this analysis. Logistic regression analyses examined the association between baseline hypertension and treatment status and past melanoma history. Survival analyses examined the association between hypertension and melanoma risk, and the effect of aspirin across hypertension groups. Cox proportional hazards models were used to compare incidence across groups.Results19,114 participants (median age of 74 years) were randomised to daily 100 mg aspirin or placebo. At baseline, hypertension and past melanoma history were recorded in 14,195 and 685 individuals, respectively. After adjustment for confounders, hypertension was significantly associated with past melanoma history (OR=1.34, 95%CI: 1.11–1.62). In a prospective analysis, baseline hypertension was not associated with melanoma risk. However, aspirin was associated with a reduced risk of incident melanoma amongst individuals with uncontrolled hypertension (blood pressure ≥140/90 mmHg; HR=0.63, 95%CI 0.44–0.89), but not in those with controlled hypertension (HR=1.04, 95%CI 0.74–1.46).ConclusionOur results support a reduced melanoma incidence amongst individuals with uncontrolled hypertension exposed to aspirin. Additional studies are required to confirm these findings.  相似文献   
92.
93.
In the post-natal growth plate, chondrocytes are arranged in columns parallel to the long axis of the bone. Chondrocytes divide perpendicular to this axis and then move into position one on top of another in a process called "rotation" that maintains columnar organization. Primary cilia are non-motile microtubule base appendages extending from the surface of almost all vertebrate cells. Primary cilia were described on chondrocytes almost 40 years ago but the function of these structures in cartilage biology is not known. Intraflagellar transport (IFT) is the process by which primary cilia are generated and maintained. This study tested the hypothesis that IFT plays an important role in post-natal skeletal development. Kif3a, a subunit of the Kinesin II motor complex, that is required for intraflagellar transport and the formation of cilia, was deleted in mouse chondrocytes via Col2a-Cre-mediated recombination. Disruption of IFT resulted in subsequent depletion of cilia and post-natal dwarfism due to premature loss of the growth plate likely a result of reduced proliferation and accelerated hypertrophic differentiation of chondrocytes. Cell shape and columnar orientation in the growth plate were also disrupted suggesting a defect in the process of rotation. Alterations in chondrocyte rotation were accompanied by disruption of the actin cytoskeleton and alterations in the localization of activated FAK to focal adhesion-like structures on chondrocytes. This is the first report indicating a role for IFT and primary cilia in the development of the post-natal growth plate. The results suggest a model in which IFT/cilia act to maintain the columnar organization of the growth plate via the process of chondrocyte rotation.  相似文献   
94.
Primary mesenchyme cells (PMCs) are solely responsible for the skeletogenesis during early larval development of the sea urchin, but the cells responsible for late larval and adult skeletal formation are not clear. To investigate the origin of larval and adult skeletogenic cells, I first performed transplantation experiments in Pseudocentrotus depressus and Hemicentrotus pulcherrimus, which have different skeletal phenotypes. When P. depressus PMCs were transplanted into H. pulcherrimus embryos, the donor phenotype was observed only in the early larval stage, whereas when secondary mesenchyme cells (SMCs) were transplanted, the donor phenotype was observed in late and metamorphic larvae. Second, a reporter construct driven by the spicule matrix protein 50 (SM50) promoter was introduced into fertilized eggs and their PMCs/SMCs were transplanted. In the resultant 6-armed pluteus, green fluorescent protein (GFP) expression was observed in both PMC and SMC transplantations, suggesting SMC participation in late skeletogenesis. Third, transplanted PMCs or SMCs tagged with GFP were analyzed by PCR in the transgenic chimeras. As a result, SMCs were detected in both larval and adult stages, but GFP from PMCs was undetectable after metamorphosis. Thus, it appears that SMCs participate in skeletogenesis in late development and that PMCs disappear in the adult sea urchin, suggesting that the skeletogenesis may pass from PMCs to SMCs during the late larval stage.  相似文献   
95.
Modelling of anaerobic digestion systems is difficult because their performance is complex and varies significantly with influent characteristics and operational conditions. In this study, Adaptive Neuro-Fuzzy Inference System (ANFIS) were used for modelling of anaerobic digestion system of primary sludge of Kayseri municipal WasteWater Treatment Plant (WWTP). Effluent Volatile Solid (VS) and methane yield were predicted by the ANFIS. Two stage models were performed. In the first stage, effluent VS concentration was predicted using pH, VS concentration, flowrate of pre-thickened sludge and temperature of the influent as input parameters. In the second stage, effluent VS concentration in addition to first stage input parameters were used as input parameters to predict methane yield. The low Root Mean Square Error (RMSE) and high Index of agreement (IA) values were obtained with subtractive clustering method of a first order Sugeno type inference. The model performance was evaluated with statistical parameters. According to statistical evaluations, the models satisfactorily predict effluent VS concentration and methane yield.  相似文献   
96.
The explosive growth of the bioinformatics field has led to a large amount of data and software applications publicly available as web resources. However, the lack of persistence of web references is a barrier to a comprehensive shared access. We conducted a study of the current availability and other features of primary bioinforo matics web resources (such as software tools and databases). The majority (95%) of the examined bioinformatics web resources were found running on UNIX/Linux operating systems, and the most widely used web server was found to be Apache (or Apache-related products). Of the overall 1,130 Uniform Resource Locators (URLs) examined, 91% were highly available (more than 90% of the time), while only 4% showed low accessibility (less than 50% of the time) during the survey. Furthermore, the most common URL failure modes are presented and analyzed.  相似文献   
97.
Despite the significant improvements achieved over the last ten years, primary education attainment in Mozambique is still low. Potential reasons acting from the demand perspective include ill health, among other factors. In Mozambique, ill health is still largely linked to malaria, which is a leading cause of outpatient contacts, hospital admissions and death, particularly among under-five and school-aged children. Despite this, in Mozambique and more generally, in malaria endemic countries, the identification and measurement of how improved malaria indicators may contribute to better school outcomes remains largely unknown. In particular, there is a low understanding of the extent to which better health translates immediately into school indicators, such as absenteeism and grades. In this study, we exploit the first year of a malaria elimination initiative implemented in Magude district (Southern Mozambique) that started in 2015, as a quasi-experiment to estimate the impact of malaria on selected primary school outcomes. While malaria was not eliminated, its incidence drastically dropped. We use as control a neighbouring district (Manhiça) with similar socio-economic and epidemiological characteristics. By employing a difference-in-differences (DiD) approach, we examine whether the positive health shock translated into improved school outcomes. Using information from school registers, we generated a dataset on school attendance and grades for 9,848 primary-school students from 9 schools (4 in the treated district and 5 in the control district). In our main specification, a repeated cross-section analysis, we find that the elimination initiative led to a 28% decrease in school absenteeism and a 2% increase in students’ grades. Our results are robust across different specifications, including a panel DiD individual fixed effects estimate on a sub-sample of students. These findings provide evidence on the negative impact of malaria on primary education attainment and suggest remarkable economic benefits consequent to its elimination.  相似文献   
98.
为了建立原代鸡胚细胞的传代培养工艺,探究传代鸡胚细胞对麻疹病毒的敏感性和适应性,本研究将原代鸡胚细胞进行传代培养,分别采用原代鸡胚细胞和传代鸡胚细胞培养麻疹病毒沪-191(Shanghai-191,S-191)株毒种,并对病毒收获液进行滴度检测和基因序列测定。结果显示,原代鸡胚细胞可稳定传代培养至第10代,各代次细胞生长趋势相似;第5代鸡胚细胞染色体检查为正常染色体核型;第8代鸡胚细胞成瘤性检查未见成瘤;采用第3、5代鸡胚细胞制备的麻疹病毒滴度水平高于原代鸡胚细胞,但无显著性差异(n=3,P>0.05),编码病毒核蛋白(nucleoprotein,N)和血凝素蛋白(hemagglutinin,H)的基因序列与S-191株完全一致,未发生变异。本研究证实,原代鸡胚细胞可进行传代培养,各代次鸡胚细胞对麻疹病毒的敏感性不变,产毒水平无显著差异,可用于培养麻疹病毒。  相似文献   
99.
摘要 目的:探讨实时影像融合的超声虚拟导航技术联合射频消融术治疗原发性肝癌合并门静脉癌栓患者的疗效及对血清BCL-2同源的水溶性相关蛋白(Bax)、细胞角蛋白19片段(Cyfra21-1)的影响。方法:选择本院2017年1月到2021年4月收治的原发性肝癌合并门静脉癌栓患者82例作为研究对象,根据1:1随机数字表法将患者分为虚拟导航组与对照组各41例,虚拟导航组给予实时影像融合的超声虚拟导航技术联合射频消融术治疗,对照组给予单纯超声引导联合射频消融术治疗。结果:虚拟导航组的进针次数、融合时间、布针时间少于对照组(P<0.05);虚拟导航组治疗后3个月的胆汁瘤、肝脓肿、膈肌损伤、肺部感染等并发症发生率为4.9 %,低于对照组的29.3 %(P<0.05)。虚拟导航组治疗后3个月的总有效率为82.9 %,高于对照组的51.2 %(P<0.05)。两组治疗后3个月的血清谷丙转氨酶(ALT)、谷草转氨酶(AST)水平低于治疗前,虚拟导航组低于对照组(P<0.05)。两组治疗后的血清Bax、Cyfra21-1含量低于治疗前,虚拟导航组低于对照组(P<0.05)。结论:实时影像融合的超声虚拟导航技术联合射频消融术治疗原发性肝癌合并门静脉癌栓能降低血清Bax、Cyfra21-1含量,改善患者的肝功能,提高消融效率,还可减少并发症的发生,最终提高患者的总体治疗效果。  相似文献   
100.
摘要 目的:研究术前三叶因子1(TFF1)、热休克蛋白70(HSP70)、天冬氨酸-天冬酰胺β羟化酶(ASPH)与原发性肝癌(PHC)患者手术切除术后早期复发的关系。方法:选取2018年1月~2019年12月我院收治的83例PHC患者,均行手术切除治疗,术后均随访2年,根据是否复发分为复发组49例以及未复发组34例。比较两组术前TFF1、HSP70、ASPH水平差异,收集患者基线资料,采用多因素Logistic回归分析PHC患者手术切除术后早期复发的危险因素,采用受试者工作特征(ROC)曲线分析术前TFF1、HSP70、ASPH水平预测PHC患者手术切除术后早期复发的效能。结果:复发组术前TFF1、HSP70、ASPH水平均高于未复发组(P<0.05)。复发组肿瘤直径≥5 cm、肿瘤数目为多发、有血管侵犯的患者比例高于未复发组(P<0.05)。多因素Logistic回归分析结果显示:肿瘤直径≥5 cm、多发肿瘤、血管侵犯及术前TFF1、HSP70、ASPH高水平是PHC患者手术切除术后早期复发的危险因素(均OR>1,P<0.05)。ROC曲线分析结果显示:术前TFF1、HSP70、ASPH联合检测预测PHC患者手术切除术后早期复发的曲线下面积为0.815,明显高于上述三项指标单独检测的0.704、0.713、0.707。结论:术前TFF1、HSP70、ASPH与PHC患者手术切除术后早期复发密切相关,联合检测三项指标水平可能有助于预测PHC患者手术切除术后早期复发。  相似文献   
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