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1.
Koppelstaetter C Jennings P Hochegger K Perco P Ischia R Karkoszka H Mayer G 《Mechanisms of ageing and development》2005,126(12):1331-1333
Telomere length is a well established marker of cellular senescence and thus biological age. Quantitative PCR allows the determination even from very low amounts of tissue by using telomere specific and single copy gene primers. Comparing a directly processed tissue sample to a 4% formaldehyde fixed one showed a significantly reduced efficiency of PCR reactions (mainly in single copy gene experiments) in a storage time-dependent manner resulting in an artificial increase in reported relative telomere length. This effect was not seen when the tissue was stored in RNA later solution. In summary, telomere length determination from formaldehyde fixed material by quantitative PCR is not a reliable method. Unfortunately therefore, many easily accessible tissue samples from pathology laboratories are unsuitable for this technique. 相似文献
2.
《Research in microbiology》2021,172(6):103870
We previously reported the complete genome of Streptomyces lavendulae subsp. lavendulae CCM 3239, containing the linear chromosome and the large linear plasmid pSA3239. Although the chromosome exhibited replication features characteristic for the archetypal end-patching replication, it lacked the tap/tpg gene pair for two proteins essential for this process. However, this archetypal tpgSa-tapSa operon is present in pSA3239. Complete genomic sequence of the S. lavendulae Del-LP strain lacking this plasmid revealed the circularization of its chromosome with a large deletion of both arms. These results suggest an essential role of pSA3239-encoded TapSa/TpgSa in the end-patching replication of the chromosome. 相似文献
3.
目的:探讨非小细胞肺癌(NSCLC)组织中端粒酶活性与p16基因的相关性及二者与肺癌发生发展的关系.方法:肺癌标本48例,12例癌旁组织,7例非肿瘤病例的正常肺组织.以Telomerase PCR ELISA检测标本端粒酶活性,以RT-PCR的方法检测p16基因mRNA转录情况,以免疫组化方法检测组织标本p16蛋白表达.结果:1)肺癌组织标本36/48(75.00%)和1例癌旁组织检出端粒酶活性.2)48例NSCLC组织中32例进行了p16 mRNA及蛋白表达检测.16/32(50.00%)检测到p16mRNA转录,7例正常组织中均检测到p16 mRNA转录.NSCLC组织标本中17/32(53.13%)未检测到p16蛋白表达,7例正常肺组织中均检测到p16蛋白表达.3)24例端粒酶阳性NSCLC组织中15例p16 mRNA表达缺失,8例端粒酶阴性的NSCLC组织中仅1例p16mRNA表达缺失.相关系数为-0.433,P=0.013,具有显著负相关.结论:端粒酶、p16基因在NSCLC的发生发展中起重要作用,端粒酶活性有望成为预测肿瘤发生、肿瘤诊断的良好指标.端粒、端粒酶与p16基因可能成为抗肿瘤治疗的新靶点. 相似文献
4.
目的建立非同位素标记的探针杂交测定外周血白细胞端粒DNA长度的方法,借此探讨无偿献血对献血者造血系统的影响。方法酚/氯仿提取基因组DNA,限制性内切酶消化,琼脂糖凝胶电泳,非同位素标记的探针Southern印迹杂交,化学发光X线片曝光显示杂交谱带,积分光密度扫描计算TRF值。结果所测样本获得了较好的低背景杂交谱带,测得35~40岁无偿献血组TRF值平均为11.73kb,相应无献血史对照组平均为11.78kb。结论建立了非同位素标记的探针检测端粒DNA的方法,用上述方法初步显示了固定的长期无偿献血并未对献血者的造血系统产生负面影响。 相似文献
5.
6.
1型糖尿病患者外周血白细胞端粒长度的变化及其意义 总被引:2,自引:0,他引:2
目的 探讨1型糖尿病(T1DM)患者外周血白细胞端粒长度的变化及意义.方法 T1DM患者(T1DM组)20例,健康对照组20例,提取外周血白细胞DNA,纯度检测合格后用地高辛标记的探针行Southern杂交,经图像分析系统扫描和软件分析后测得端粒长度.结果 T1DM组外周血白细胞端粒长度较对照组明显缩短(P< 0.01).结论 T1DM患者外周血白细胞端粒长度的缩短可能与自身免疫密切相关,提示端粒可能在T1DM的发病中起重要作用. 相似文献
7.
Buyun Liu Yangbo Sun Guifeng Xu Linda G. Snetselaar Gabriele Ludewig Robert B. Wallace Wei Bao 《Journal of the Academy of Nutrition and Dietetics》2019,119(4):617-625
Background
Excess iron levels can induce oxidative stress and could therefore affect telomere attrition. However, little is known about the impact of body iron status on telomere length.Objective
Our aim was to examine the association between serum ferritin concentrations, an indicator of body iron status, and leukocyte telomere length in US adults.Design
We conducted a nationwide, population-based, cross-sectional study.Participants/setting
We used data from the National Health and Nutrition Examination Survey (NHANES) 1999-2002. We included 7,336 adults aged 20 years or older who had available data on serum ferritin levels and telomere length. High ferritin levels were defined as a serum ferritin level >200 ng/mL (449.4 pmol/L) in women and >300 ng/mL (674.1 pmol/L) in men. Low ferritin levels were defined as a serum ferritin level <30 ng/mL (67.4 pmol/L).Main outcome measures
Leukocyte telomere length was assayed using the quantitative polymerase chain reaction method.Statistical analyses
Linear regression with survey weights was performed to estimate the association between serum ferritin levels and telomere length.Results
The prevalence of adults with high and low serum ferritin levels was 10.9% and 17.6%, respectively. High ferritin levels were inversely associated with telomere length compared to normal ferritin levels. After adjustment for demographic, socioeconomic and lifestyle factors, body mass index, C-reactive protein, and leukocyte cell type composition, the β coefficient for log-transformed telomere length was –0.020 (standard error [SE]=0.009; P=0.047). The association was stronger in adults aged 65 years or older (β coefficient –0.081, SE=0.017; P<0.001) than in adults 20 to 44 years old (β coefficient –0.023, SE=0.019; P=0.24) or adults aged 45 to 64 years old (β coefficient 0.024, SE=0.015; P=0.10) (P for interaction 0.003). Low ferritin levels were not significantly associated with telomere length compared with normal ferritin levels.Conclusions
In a US nationally representative population, high body iron status was associated with shorter telomeres, especially in adults aged 65 years or older. 相似文献8.
9.
AIM: Telomere shortening has been reported in several diseases including atherosclerosis and Type 1 diabetes. Asian Indians have an increased predilection for Type 2 diabetes and premature coronary artery disease. The aim of this study was to determine whether telomeric shortening occurs in Asian Indian Type 2 diabetic patients. METHODS: Using Southern-blot analysis we determined mean terminal restriction fragment (TRF) length, a measure of average telomere size, in leucocyte DNA. Type 2 diabetic patients without any diabetes-related complications (n = 40) and age- and sex-matched control non-diabetic subjects (n = 40) were selected from the Chennai Urban Rural Epidemiology Study (CURES). Plasma level of malondialdehyde (MDA), a marker of lipid peroxidation, was measured by TBARS (thiobarbituric acid reactive substances) using a fluorescence method. RESULTS: Mean (+/- SE) TRF lengths of the Type 2 diabetic patients (6.01 +/- 0.2 kb) were significantly shorter than those of the control subjects (9.11 +/- 0.6 kb) (P = 0.0001). Among the biochemical parameters, only levels of TBARS showed a negative correlation with shortened telomeres in the diabetic subjects (r = -0.36; P = 0.02). However, telomere lengths were negatively correlated with insulin resistance (HOMA-IR) (r = -0.4; P = 0.01) and age (r = -0.3; P = 0.058) and positively correlated with HDL levels (r = 0.4; P = 0.01) in the control subjects. Multiple linear regression (MLR) analysis revealed diabetes to be significantly (P < 0.0001) associated with shortening of TRF lengths. CONCLUSIONS: Telomere shortening occurs in Asian Indian Type 2 diabetic patients. 相似文献
10.
Inken Padberg Sabrina Janßen Thomas F. Meyer 《International journal of medical microbiology : IJMM》2013,303(8):463-474
Epidemiological data exist to support a positive association between Chlamydia trachomatis (Ctr) infection and gynecological cancers; however, putative cellular mechanisms for this association are lacking. Here, we identified Ctr-induced perturbations to host cell phenotypes in vitro that persisted after clearance of infection and could directly contribute to host cell transformation. In particular, human telomerase catalytic subunit (hTERT) mRNA expression and catalytic subunit activity were increased in acute infected late passage IMR90E1A cells. hTERT upregulation was accompanied by recruitment of ceramide, a known regulator of hTERT, to the chlamydial inclusion and was abrogated following doxycycline-mediated infection clearance. In cells cleared of Ctr infection, average telomere length was slightly increased and immunofluorescence staining of the DNA damage marker γH2A.X was reduced after clearance of infection compared with cells that had not been infected. Reduced p53 binding to the promoter of the cell cycle checkpoint regulator p21 was also detected in cells cleared of infection and p21 levels were reduced; moreover, this cell population exhibited increased resistance to etoposide-induced DNA damage. Thus, Ctr infection altered cell aging and survival pathways, which persisted after infection clearance. Cells that survive infection are likely to exhibit altered physiology, as evidenced by an increased resistance to DNA damage-induced apoptosis, which may support cellular transformation. 相似文献