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81.
Previous studies have reported converging lung cancer rates between sexes. We examine lung cancer incidence rates in young women vs. young men in 40 countries across five continents. Lung and bronchial cancer cases by 5-year age group (ages 30–64) and 5-year calendar period (1993–2012) were extracted from Cancer Incidence in Five Continents. Female-to-male incidence rate ratios (IRRs) and 95% confidence intervals (95%CIs) were calculated by age group and birth cohort. Among men, age-specific lung cancer incidence rates generally decreased in all countries, while in women the rates varied across countries with the trends in most countries stable or declining, albeit at a slower pace compared to those in men. As a result, the female-to-male IRRs increased among recent birth cohorts, with IRRs significantly greater than unity in Canada, Denmark, Germany, New Zealand, the Netherlands and the United States. For example, the IRRs in ages 45–49 year in the Netherlands increased from 0.7 (95% CI: 0.6–0.8) to 1.5 (95% CI: 1.4–1.7) in those born circa 1948 and 1963, respectively. Similar patterns, though nonsignificant, were found in 23 additional countries. These crossovers were largely driven by increasing adenocarcinoma incidence rates in women. For those countries with historical smoking data, smoking prevalence in women approached, but rarely exceeded, those of men. In conclusion, the emerging higher lung cancer incidence rates in young women compared to young men is widespread and not fully explained by sex differences in smoking patterns. Future studies are needed to identify reasons for the elevated incidence of lung cancer among young women.  相似文献   
82.
83.
目的探讨奥沙利铂如何调控MAPK通路,抑制胃癌细胞的增殖。方法NCBI检索文献,利用TargetScan、StarBase和miRBase数据库,进行GO分析与KEGG通路富集,找到相关miRNAs,预测靶基因。应用Real-time PCR、MTT、Hoechst33258、流式细胞术、细胞划痕实验、Western blot等方法分析人胃癌SGC-7901细胞的增殖、细胞周期、侵袭及蛋白表达情况。结果胃癌细胞中miR-7-5p显著低表达,RAF1与miR-7-5p存在互靶关系。miR-7-5p mimics与奥沙利铂均可促进SGC-7901细胞的凋亡,提高G1期细胞百分率(P<0.05),降低侵袭、迁移速度。caspase3、caspase9蛋白表达升高,Bcl-2/Bax比值降低(P<0.05)。结论过表达miR-7-5p与奥沙利铂均可促进胃癌SGC-7901细胞的凋亡,提示奥沙利铂可能通过上调miRNA-7-5p促进SGC-7901细胞的凋亡,降低侵袭、迁移速度。  相似文献   
84.
Non‐structural viral protein 5B (NS5B) is a viral protein in hepatitis C virus. Although various inhibitors against NS5B have been found, the activity prediction of similar untested inhibitors is still highly desirable. In this respect, the Tchebichef moments (TMs) calculated from the images of molecular structures were regarded as the independent variables while the inhibitory activity (pIC50) was the dependent variable, and the predictive model was established by means of stepwise regression. The R‐squared of leave‐one‐out cross‐validation (Q2) for the training set and the R‐squared of prediction () for external independent test set were 0.919 and 0.927, respectively. The obtained model was also evaluated strictly. Compared with the multivariate curve resolution with alternating least squares (MCR‐ALS) and the QSAR approaches derived from the literature, the proposed method is more accurate and reliable. This study not only provides an effective approach to predict the biological activity of RNA replication's inhibitors, but also extends the QSAR modeling technique.  相似文献   
85.
《Neuro-Chirurgie》2022,68(2):239-242
IntroductionIndocyanine green (ICG) is commonly used to visualize cerebral vasculature, particularly in the management of cerebral aneurysms. There have also been attempts to use ICG for visualization of tumors. Injection of ICG followed by immediate fluorescence microscopy is limited by the short time window for imaging and administration and restricted depth of imaging. Second Window Indocyanine Green (SWIG) addresses these issues by allowing for longer contrast times and the imaging of deeper regions of brain tissue. Biopsy of spinal cord lesions is often difficult for a variety of reasons, including the delicate nature of the tissue and differentiating normal from lesional tissue visually, especially in lesions with heterogeneous enhancement.MethodsIn this case report, we describe the use of second window ICG to facilitate the visualization of a spinal cord lesion and subsequent biopsy of the lesion.ResultsThis patient is a 24-year-old female who had recurrence of a suprasellar germinoma. An MRI of the rest of the neuraxis was performed to assess for the presence of drop metastases. The spinal cord from C2-5 was expanded with areas of patchy enhancement; however, this lesion was asymptomatic. The patient's oncologist requested a biopsy of this lesion to help direct subsequent care of her recurrent germinoma. The day before surgery, the patient had an intravenous injection of ICG dye. She then underwent a C3-5 laminectomy for biopsy of her cervical intramedullary lesion. After opening of the dura, no visible abnormality of the spinal cord could be identified. A Stryker endoscope showed an area of ICG uptake in the cord at approximately the C3-4 level. A midline myelotomy was centered over the ICG demarcated area and several samples were taken for pathology. Final biopsy results determined the lesion to be spinal cord parenchyma with perivascular and intraparenchymal lymphocytes – not consistent with spinal cord tumor or germinoma.ConclusionSecond Window ICG is effective in visualizing otherwise visually unremarkable spinal cord lesions. This technology can facilitate biopsy of these lesions and possibly their surgical resection.  相似文献   
86.
目的构建一个以二维码作为电子诊疗卡替代医院传统诊疗卡的系统。方法依托医院微医疗平台,对患者唯一标识和时间戳进行MD5计算生成字符串,并以此内容生成二维码作为电子诊疗卡,同时对HIS进行相应改造,实现电子诊疗卡在全院的应用。结果利用时间戳和MD5签名生成二维码保证了电子诊疗卡加密的唯一性、时效性,医院每年节约成本5万元,患者每次就诊时间减少5 min,提升了患者满意度。结论本文构建的二维码电子诊疗卡系统,解决了使用实体诊疗卡过程中经常出现的忘带卡和重复办卡等问题,提高了医院服务质量,改善了患者就医体验。  相似文献   
87.
Solute carrier family 12 member 5 (SLC12A5) has an oncogenic role in bladder urothelial carcinoma. The present study aimed to characterize the molecular mechanisms of SLC12A5 in bladder urothelial carcinoma pathogenesis. Functional assays identified that in bladder urothelial carcinoma SLC12A5 interacts with and stabilizes SOX18, and then upregulates matrix metalloproteinase 7 (MMP7). In vivo and in vitro assays were performed to confirm the effect of SLC12A5’s interaction with SOX18 on MMP7‐mediated bladder urothelial carcinoma progression. SLC12A5 was upregulated in human bladder tumors, and correlated with the poor survival of patients with bladder urothelial carcinoma tumor invasion and metastasis, promoted by SLC12A5 overexpression. We demonstrated that SLC12A5 interacted with SOX18, and then upregulated MMP7, thus enhancing tumor progression. Importantly, SLC12A5 expression correlated positively with SOX18 and MMP7 expression in bladder urothelial carcinoma. Furthermore, SLC12A5 expression was suppressed by miR‐133a‐3p. Ectopic expression of SLC12A5 partly abolished miR‐133a‐3p‐mediated suppression of cell migration. SLC12A5‐SOX18 complex‐mediated upregulation on MMP7 was important in bladder urothelial carcinoma progression. The miR‐133a‐3p/SLC12A5/SOX18/MMP7 signaling axis was critical for progression, and provided an effective therapeutic approach against bladder urothelial carcinoma.  相似文献   
88.
目的:探讨人参皂苷Rg5通过抑制长链非编码RNA-PCAT12(lncRNA-PCAT12)抑制胃癌(GC)细胞增殖与迁移的价值。方法:对数生长期的人胃癌SNU-1 细胞分为四组,A组,B组与C组加入0.03,0.06,0.09 μmol/L Rg5处理,对照组加入5% DMSO进行处理。MTT法检测细胞增殖、双染法检测细胞凋亡、划痕实验检测细胞迁移、实时定量PCR检测lncRNA-PCAT12表达。结果:处理后24、48、72 h,对照组中lncRNA-PCAT12表达水平和癌细胞增殖指数高于各实验组(P<0.05),C组均低于B组与A组(P<0.05)。实验各组细胞凋亡率均比对照组高(P<0.05),C组比B组与A组高(P<0.05)。转染48 h后,实验各组细胞迁移距离都小于对照组(P<0.05),而C组小于其他两个实验组(P<0.05)。结论:人参皂苷Rg5能通过抑制lncRNA-PCAT12的表达,且高浓度的效果更显著,可通过抑制GC细胞增殖与迁移,促进其凋亡,从而发挥抑癌作用。  相似文献   
89.
Personalised cancer treatment depends on identification of therapeutically relevant biological subgroups of patients for assessing effect of treatment and to discover new therapeutic options. By analyses in heterogeneous patient populations, the effects may be lost in noise. Squamous cell carcinoma of the lung is a major killer worldwide. Despite recent advances, mortality is high and response to therapies varies greatly from patient to patient. Target search in biologically relevant subgroups may identify treatment options not so far discovered. A total of 198 patients undergoing surgery for squamous cell carcinomas of the lung were included in the study. The tumours were analysed for copy number alterations (n = 152) and gene expression from tumour (n = 188) and normal lung (n = 21), with both data levels present in 140 patients. We studied alterations in tumours harbouring mutations in TP53 and in previously published gene expression subtypes. Genes with consistent alterations in both genomic levels were identified as putative biomarkers. Results were validated in TCGA. The most convincing biomarker in TP53 mutated squamous cell carcinomas of the lung was BIRC5 with amplification in 36% of mutated samples, 5% in wild-type samples and a 17%-fold change of expression between TP53 mutated tumours and normal lung tissue. BIRC5 was significantly altered in the classical and primitive subtypes. We suggest BIRC5 as a putative predictive biomarker and putative druggable target in squamous cell lung carcinomas harbouring TP53 mutation or classified as classical and primitive subtypes.  相似文献   
90.
目的:探讨引经药防风对痛泻要方调控腹泻型肠易激综合征(IBS-D)大鼠水液代谢和5-羟色胺(5-HT)信号系统的影响。方法:将40只IBS-D SD大鼠随机分为模型组,痛泻要方缺防风组(26 g·kg^-1),痛泻要方全方组(30 g·kg^-1)和痛泻要方倍用防风组(34 g·kg^-1),另取10只正常SD大鼠作为正常组,除正常组外,其余各组采用母子分离联合乙酸灌肠法,建立腹泻型肠易激综合征大鼠模型,造模后各组灌胃给予相应药物,连续14 d,观察并计算腹泻指数和粪便含水量,微量法检测肠黏膜Na^+-K^+-ATP酶活性,酶联免疫吸附测定(ELISA)检测5-HT的含量,化学发光法检测单胺氧化酶-A(MAO-A)活性,通过免疫组化法检测结肠中水通道蛋白4(AQP4)的表达,蛋白免疫印迹法(Western blot)检测下丘脑和结肠中5-HT受体3(5-HT3R),5-HT受体4(5-HT4R)和5-HT转运体(SERT)的蛋白表达水平。结果:与正常组比较,模型组大鼠的粪便含水量,5-HT含量,MAO-A酶活性,5-HT3R表达均显著升高(P<0.01),肠黏膜Na^+-K^+-ATP酶活性,AQP4,5-HT4R和SERT表达均显著降低(P<0.01);与模型组比较,各给药组大鼠的腹泻指数和粪便含水量、下丘脑与结肠中的5-HT含量,MAO-A酶活性,5-HT3R蛋白表达均明显降低(P<0.05,P<0.01),但痛泻要方缺防风组5-HT3R蛋白表达未见明显差异,各给药组肠黏膜Na^+-K^+-ATP酶活性,AQP4,5-HT4R和SERT表达均明显增加(P<0.05,P<0.01);与痛泻要方缺防风组比较,痛泻要方全方组和痛泻要方倍用防风组大鼠腹泻指数和粪便含水量,5-HT含量及MAO-A酶活性,5-HT3R的蛋白表达均明显降低(P<0.05,P<0.01),Na^+-K^+-ATP酶活性和SERT的蛋白表达明显增加(P<0.05,P<0.01)。结论:防风可增强痛泻要方改善IBS-D水液代谢、调控5-HT信号系统多靶点的效应,进一步证实了防风的引经增效作用。  相似文献   
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