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31.
目的将IL6基因转导至成纤维细胞NIH3T3,并使转染株有效地表达IL6,为IL6转基因治疗奠定基础.方法利用重组载体构建技术将质粒pUCIL6cDNA的目的片段连接于逆转录病毒载体上,并以脂质体介导的方法将重组载体转染包装细胞PA317,以G418筛选克隆细胞,浓缩克隆细胞上清以制备重组病毒液,继之感染NIH3T3细胞后,进行Southernblot和Northernblot分析,检测目的基因在靶细胞的整合与转录水平.结果成功地构建了重组载体pZIPIL6cDNA,筛选出抗生较强的克隆细胞,制备了高滴度的重组病毒液.杂交结果表明转导株3T3IL6具有IL6基因的整合和相应mRNA的高表达.结论IL6基因能稳定整合至靶细胞并进行有效的转录表达,为IL6基因治疗的应用奠定了可靠的基础 相似文献
32.
Alexander Dimitri Miras Anna Kamocka Beln Prez-Pevida Sanjay Purkayastha Krishna Moorthy Ameet Patel Harvinder Chahal Gary Frost Paul Bassett Lidia Castagnetto-Gissey Lucy Coppin Nicola Jackson Anne Margot Umpleby Stephen Robert Bloom Tricia Tan Ahmed Rashid Ahmed Francesco Rubino 《Diabetes care》2021,44(5):1082
OBJECTIVERoux-en-Y gastric bypass (RYGB) characteristically enhances postprandial levels of glucagon-like peptide 1 (GLP-1), a mechanism that contributes to its profound glucose-lowering effects. This enhancement is thought to be triggered by bypass of food to the distal small intestine with higher densities of neuroendocrine L-cells. We hypothesized that if this is the predominant mechanism behind the enhanced secretion of GLP-1, a longer intestinal bypass would potentiate the postprandial peak in GLP-1, translating into higher insulin secretion and, thus, additional improvements in glucose tolerance. To investigate this, we conducted a mechanistic study comparing two variants of RYGB that differ in the length of intestinal bypass.RESEARCH DESIGN AND METHODSA total of 53 patients with type 2 diabetes (T2D) and obesity were randomized to either standard limb RYGB (50-cm biliopancreatic limb) or long limb RYGB (150-cm biliopancreatic limb). They underwent measurements of GLP-1 and insulin secretion following a mixed meal and insulin sensitivity using euglycemic hyperinsulinemic clamps at baseline and 2 weeks and at 20% weight loss after surgery.RESULTSBoth groups exhibited enhancement in postprandial GLP-1 secretion and improvements in glycemia compared with baseline. There were no significant differences in postprandial peak concentrations of GLP-1, time to peak, insulin secretion, and insulin sensitivity.CONCLUSIONSThe findings of this study demonstrate that lengthening of the intestinal bypass in RYGB does not affect GLP-1 secretion. Thus, the characteristic enhancement of GLP-1 response after RYGB might not depend on delivery of nutrients to more distal intestinal segments. 相似文献
33.
Shaojun Liu Dongbo Cao Zhiming Xiao Fen Liu Xiaoyan Wang Lian Zhao Li Tian Shourong Shen 《African journal of traditional, complementary, and alternative medicines》2013,10(4):78-82
The active components in Folium Cordylines Fruticosae were extracted by heat reflux method. The solvents used were distilled water and ethanol. The effects of two types of extracts on gastric cancer cells were compared; dry extract yields were calculated, as well as the inhibition rates of gastric cancer MGC-803 cell proliferation and the colony cell counts. The micro-Kjeldahl method was used to measure the cell protein contents and to make a comprehensive comparison. The results showed that the MGC-803 cell inhibition rates of three different concentrations (32.5, 75 and 150 mg/ml) of ethanol extracts increased with the increase of concentration, which was 48.9% at a concentration of 150 mg/ml; aqueous extract of Folium Cordylines Fruticosae had very low inhibitory activity at a low concentration (32.5 mg/ml), which was remained at about 20%. After being affected by two types of extracts, cells had uneven sizes, with very low brightness, while the normal cells presented a uniform full form, with high definition. 相似文献
34.
35.
[目的]观察中药解毒清肝饮联合还原型谷胱甘肽静脉滴注对酒精性肝炎的临床疗效.[方法]采用前瞻性研究方法,将酒精性肝炎患者112例随机分成2组:对照组,56例,采用普通护肝、降酶治疗(给予葡萄糖、肌苷、维生素B1、维生素C、维生素E、甘草酸二胺);治疗组,56例,在对照组治疗基础上给予中药解毒清肝饮口服联合还原型谷胱甘肽静脉滴注.观察2组患者症状和血清谷丙转氨酶(ALT)、谷草转氨酶(AST)、总胆红素(TBil)、γ-谷氨酰转移酶(γ-GT)等指标变化.[结果]治疗组总有效率(96.4%)优于对照组(73.2%);治疗前后血清生化指标ALT、AST、TBIL、γ-GT和肝脏B超影像学检查等比较,治疗组症状改善均明显优于对照组(P<0.01);治疗过程中2组均未见明显不良反应.[结论]中药解毒清肝饮联合还原型谷胱甘肽治疗酒精性肝炎优于用葡萄糖、肌苷、维生素B1、维生素C、维生素E、甘草酸二胺等药,且安全性相当. 相似文献
36.
37.
Jianghong Hu Yue Fang Yuan Cao Rong Qin Qiaoyun Chen 《Digestive diseases and sciences》2014,59(2):336-345
Background
Recently, several miRNAs have been determined as tumor suppressors in various cancers, such as microRNA-449a. However, the exact molecular mechanisms underlying miR-449a regulated cell proliferation and chemosensitivity in gastric cancer cells have not been well documented.Aim
The present study was designed to test whether miR-449a mediates cell proliferation and chemosensitivity in gastric cancer cells via regulating cyclin D1 and BCL2.Methods
In vitro, the ability of cell proliferation and cell viability were measured by MTT assay; cell cycle and cell apoptosis was detected by FCM. qRT-PCR was used to measure the expression of miR-449a. Western blot and real-time PCR assays were used to detect the expression of cyclin D1 and BCL2 in gastric cancer cell line SGC7901.Results
miR-449a expression was downregulated in gastric cancer cell line SGC7901 and human gastric cancer tissues, compared to the gastric epithelial cell line GES-1 and matched non-tumor associated tissues. Upregulation of miR-449a reduced the proliferation of SGC7901 cells. Ectopic expression of miR-449a decreased the percentage of S phase cells, increased the percentage of G1/G0 phase cells and increased the apoptosis induced by cisplatin. Moreover, miR-449a inhibited SGC7901 cells proliferation and enhanced cisplatin chemosensitivity by downregulating expression of BCL2 and cyclin D1, respectively, via directly targeting the 3′-untranslated regions of BCL2 and cyclin D1 mRNA.Conclusions
This is the first report to provide evidence that miR-449a could modulate cell cycle and apoptosis through regulating cyclin D1 and BCL2 expression in SGC7901 cells. 相似文献38.
Mucosal surfaces are key interfaces between the host and its environment, but also constitute ports of entry for numerous pathogens. The gut and lung mucosae act as points of nutrient and gas exchange, respectively, but the physiological purpose of the female reproductive tract (FRT) is to allow implantation and development of the fetus. Our understanding of immune responses in the FRT has traditionally lagged behind our grasp of the situation at other mucosal sites, but recently reproductive immunologists have begun to make rapid progress in this challenging area. Here, we review current knowledge of immune responses in the human FRT and their heterogeneity within and between compartments. In the commensal-rich vagina, the immune system must allow the growth of beneficial microbes, whereas the key challenge in the uterus is allowing the growth of the semi-allogeneic fetus. In both compartments, these objectives must be balanced with the need to eliminate pathogens. Our developing understanding of immune responses in the FRT will help us develop interventions to prevent the spread of sexually transmitted diseases and to improve outcomes of pregnancy for mothers and babies. 相似文献
39.
Qianwen Zhao Meng Meng Rahul Kumar Yinlian Wu Jiaofeng Huang Ningfang Lian Yunlei Deng Su Lin 《Journal of medical virology》2020,92(10):1915-1921
Comorbidities are associated with the severity of coronavirus disease 2019 (COVID-19). This meta-analysis aimed to explore the risk of severe COVID-19 in patients with pre-existing chronic obstructive pulmonary disease (COPD) and ongoing smoking history. A comprehensive systematic literature search was carried out to find studies published from December 2019 to 22 March 2020 from five databases. The languages of literature included English and Chinese. The point prevalence of severe COVID-19 in patients with pre-existing COPD and those with ongoing smoking was evaluated with this meta-analysis. Overall 11 case series, published either in Chinese or English language with a total of 2002 cases, were included in this study. The pooled OR of COPD and the development of severe COVID-19 was 4.38 (fixed-effects model; 95% CI: 2.34-8.20), while the OR of ongoing smoking was 1.98 (fixed-effects model; 95% CI: 1.29-3.05). There was no publication bias as examined by the funnel plot and Egger's test (P = not significant). The heterogeneity of included studies was moderate for both COPD and ongoing smoking history on the severity of COVID-19. COPD and ongoing smoking history attribute to the worse progression and outcome of COVID-19. 相似文献
40.
Autoimmune hepatitis (AIH), primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) are complex disorders, resulting from the interaction of genetic and environmental factors. For many years, investigators have attempted to delineate the genetic architecture of these conditions, aiming to elucidate disease pathogenesis and identify molecular targets for pharmacotherapy. Early genetic studies consisted of HLA association studies and non-HLA candidate gene association studies, designed to identify association with selected HLA or non-HLA loci. HLA association studies identified HLA risk loci that are now well-established. Non-HLA candidate gene studies were less fruitful because they were mostly underpowered to detect modest effects and were frequently designed to investigate one or two functional polymorphisms, meaning that gene coverage was poor. Furthermore, weak associations detected in one small cohort were often never validated. If replication studies were undertaken, the results were often conflicting. More recently, a series of genome-wide association studies (GWAS) and related study designs have evaluated the impact of common genetic variants (frequency >5% in the general population) across the entire genome. These studies have identified several non-HLA risk loci for autoimmune liver disease. The majority of risk loci detected are similar to those of non-hepatic immune-mediated diseases, suggesting that outcomes from GWAS and related genetic studies reflect broad phenotypic themes rather than traditional clinical conditions. The specific genetic basis of these PBC and PSC associated inflammatory themes as determined by GWAS is described and discussed in the context of interacting genetic and non-genetic (including environmental) factors. 相似文献