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排序方式: 共有534条查询结果,搜索用时 15 毫秒
31.
Narendra Joshi Sadhana Kannan Nirupama Kotian Shreyas Bhat Mithila Kale Sujata Hake 《Human immunology》2014
In our earlier studies, single nucleotide polymorphisms (SNPs) associated with anti-inflammatory cytokines were found to influence risk for breast cancer in western Indian women. Analysis of Interleukin 6 (IL-6) −174G>C polymorphism in this cohort (patients = 182; controls = 236) suggested a protective role for IL-6 −174C allele associated with the lower expression of the cytokine (OR = 0.54; 95% CI 0.32–0.89, dominant model). Together these observations suggested that in comparison to Caucasians, inflammation associated-cytokine gene polymorphisms may have higher influence on risk for cancer in this population. To examine this possibility we analyzed data assessing influence of Interleukin 6 (IL-6) −174G>C polymorphism on risk for various cancers. Overall, there was a marginally higher risk for rare allele homozygotes compared to wild type homozygotes (OR = 1.07; 95% CI 1.00–1.15). Increased risks for genitourinary cancers and for skin cancer were also indicated. The ethnicity based analysis indicated a protective effect of the minor allele in Ancestral North Indians (OR = 0.73; 95% CI 0.55–0.97). Site by ethnicity analysis once again revealed a significant protection against breast cancer (OR = 0.51; 95% CI = 0.37–0.70; dominant model) but an opposite influence on the risk of genitourinary malignancies (OR = 2.51; 95% CI 1.59–3.96; recessive model) in this population alone. The observations imply that contribution of IL-6 to inflammation or effector immunity may depend on the site of malignancy. Assessment of available data in relation to prognosis in breast cancer patients also revealed trends that are compatible with the observations of the meta-analysis. Thus, IL-6 −174G>C polymorphism clearly represents a potential modulator of risk for malignant disorders with ethnicity and site dependent trends. The results also support the possibility of higher influence of inflammation related cytokine gene polymorphisms on the risk for cancers in Ancestral North Indians. 相似文献
32.
Holstein haplotype (HH) 1, 3 and 4 are lethal mutations, responsible for early embryonic losses in Holstein Friesian (HF) cattle, worldwide. Three PCR based assays – tetra Amplification Refractory Mutation System PCR, PCR primer induced restriction analysis and PCR-restriction fragment length polymorphism techniques for screening of HH1, 3 and 4, respectively were developed and validated. During screening, six among 60 HF bulls were found as carrier for either of three mutations. These PCR assays are highly accurate and reproducible and can be used for screening of the haplotypes in HF cattle. 相似文献
33.
[目的]利用聚合酶链式反应-限制性片段长度多态性(PCR-RFLP),建立快速鉴别大蓟混伪品飞廉和魁蓟的方法。[方法]通过比对ITS基因序列,分别筛选飞廉、魁蓟的限制性内切酶位点并设计鉴别引物。考察PCR反应的退火温度、循环数及不同酶的适用性,对酶切反应时间和酶切底物量进行优化。同时对该方法适应性及掺伪比例的专属性、稳定性进行考察。[结果]当退火温度为58~60℃、循环数为30个时,样品均能扩增出一条379 bp的DNA条带。底物为8μL、酶切温度为37℃、酶切反应120 min时,ZraI酶将飞廉切割成120 bp和259 bp两条DNA条带;DNA底物为8μL、酶切温度为37℃、酶切反应60 min时,ApaLI酶将魁蓟切割成126 bp和253 bp两条DNA条带。[结论]试验建立的PCR-RFLP方法能够准确地鉴别大蓟混伪品飞廉、魁蓟,避免此类药材的混用,以保证临床用药安全。 相似文献
34.
35.
Amir FarmohammadiAli MomeniBanafshe BahmaniHossein GhorbaniRamin Ramzanpour 《Asian Pacific journal of cancer prevention》2020,21(1):255-258
Background: Paraoxonase 1 (PON1), a multifactorial antioxidant enzyme, has a defensive role against oxidative stress, which is believed to contribute to cancer development. This study aimed to investigate the association of PON1-L55M functional polymorphism with breast cancer risk. Material and methods: In the experimental study, blood samples were collected from 150 healthy women controls and 150 breast cancer subjects. The L55M genotyping was performed by polymerase chain reaction-restriction fragment length polymorphism. Results: Our analysis showed that the genotypes distribution is in Hardy-Weinberg equilibrium for both case and control groups. Our data revealed that there are significant associations between PON1-L55M polymorphism and breast cancer risk in homozygote (OR= 2.13, 95%CI= 1.14-4.00, p= 0.018), dominant (OR= 1.72, 95%CI= 1.07-2.76, p= 0.024), and allelic (OR= 1.55, 95%CI= 1.12-2.15, p= 0.008) models. Conclusions: Our results suggest that the PON1-L55M genetic variation could be a genetic risk factor for breast cancer risk and it could be considered as a molecular biomarker for screening of susceptible women. 相似文献
36.
37.
Cytochrome P450 CYP1A1 is a phase 1 xenobiotic metabolizing enzyme involved in the metabolism of toxins, endogenous hormones and pharmaceutical drugs. It is therefore possible that polymorphism of CYP1A1 gene producing functional changes in the enzyme may be susceptible factors in cervical carcinogenesis. This study was aimed to look association of CYP1A1 m1 (T > C) and m2 (A > G) gene polymorphisms in Chhattisgarh population. In this case-control study, we analyzed leukocyte DNA from a total of 200 subjects form Chhattisgarh (100 cases and 100 controls). All subjects were genotyped for CYP1A1 m1 (T > C) and m2 (A > G) using PCR-RFLP with statistical analysis by using SPSS version 16.0 and VassarStats (online). Among the two gene variants rs4646903 (T > C) and rs1048943 (A > G), individuals with AG and GG genotypes of CYP1A1 m2 polymorphism have significantly higher and increased risk of cervical cancer (OR = 2.0, 95%CI = 1.04-3.84, p = 0.035; OR = 62.9, 95%CI = 3.72-1063.83, p = 0.004 respectively) and the association of CYP1A1 m1 polymorphism did not show any significant relationship with cervical cancer patients (p = 0.23). The ‘G’ allele showed strong association with the disease (p < 0.0001). Thus, CYP1A1 m2 polymorphism showed an increased risk in the population leading to cervical cancer. Our study suggested that the presence of ‘C’ allele of rs4646903 (T > C) showed no risk and ‘G’ allele of rs1048943 (A > G) might be a leading allele to cause increased cervical cancer susceptibility due to significant association of CYP1A1 m2 gene polymorphism. 相似文献
38.
目的:寻找简便、可重复的分子标记方法对绞股蓝属Gynostemma植物及其混淆品乌蔹莓Cayratia japonica进行鉴别。方法:对7种常见药用绞股蓝属植物及其混淆品乌蔹莓的6个cpDNA片段进行PCR 扩增,再利用TaqⅠ,HpaⅡ,EcoRⅠ,RsaⅠ,HhaⅠ,HindⅢ等6种限制性内切酶分别对扩增片段进行消化。结果:36种DNA片段/内切酶组合中,trnK1f -trnK2r片段与RsaⅠ组合可将乌蔹莓从绞股蓝属植物中区分出来,产物清晰、结果稳定。结论:PCR-RFLP分析方法可有效区分常见绞股蓝属植物与其混淆品乌蔹莓。 相似文献
39.
有研究显示,体液中的游离核酸可直接用于肿瘤的分子诊断,且效果优于以体液中的脱落细胞为实验材料[1].近年来随着肿瘤发病率的上升,恶性浆膜腔积液的比例不断升高,但部分恶性积液的诊断一直困扰人们.ras基因第12密码子突变广泛存在于多种恶性肿瘤,是研究肿瘤基因诊断较为理想的"通用"靶基因之一.本研究以浆膜腔积液上清为标本对K-ras和H-ras基因第12密码子突变进行聚合酶链反应扩增及限制性片段长度多态性(PCRRFLP)分析,探讨它们对恶性积液的诊断价值. 相似文献
40.
目的:了解护骨素(osteoprotegerin,OPG)基因启动子区A163G、T245G和T950C位点多态性对青春前期汉族女童骨密度(BMD)的影响。方法:采用PCR-RFLP技术检测广州地区214名青春前期女童护骨素基因三个位点的基因型。采用双能X线骨密度仪测量全身、腰椎(L1-4)、股骨颈和Ward三角区骨矿含量(BMC)和骨密度。同时测定三种骨代谢生化指标。结果:OPG基因启动子区A163G、T245G和T950C位点基因型分布频率均符合Hardy-Weinberg遗传平衡定律,分布频率分别为:A163G:AA-74.8%,AG-21.5%,GG-3.7%;T245G:TT-77.1%,TG-21.5%,GG-1.4%;T950C:TT-41.1%,TC-50.5%,CC-8.4%。T950C位点CC基因型女童的全身骨量、骨密度及股骨颈和Ward三角区骨密度均显著高于TT、TC基因型女童(P<0.05),而TT和TC基因型女童未见显著差异(P>0.05)。A163G和T245G位点多态性与女童BMC和BMD的相关性未发现有统计学意义(P>0.05)。结论:护骨素基因T950C位点含有T等位基因的青春前期女童,其全身骨密度及股骨颈和Ward’s三角区骨密度均较低,该等位基因可能为我国青春期女童低骨量者筛选的遗传学标志提供了研究方向。 相似文献