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排序方式: 共有3124条查询结果,搜索用时 31 毫秒
61.
Aris Anastasakis Christina-Maria Kotta Stavros Kyriakogonas Bernd Wollnik Artemisia Theopistou Christodoulos Stefanadis 《Europace : European pacing, arrhythmias, and cardiac electrophysiology》2006,8(4):241-244
We aimed to verify the long QT syndrome (LQTS) genotype in a family with strong evidence of LQTS type 1 (LQT1) on the basis of so far established genotype-phenotype correlations. Genetic testing for mutations in the KCNQ1 potassium channel gene revealed an A341V mutation in three generations of the family. Existing genotype-phenotype correlations were correctly predictive of the genotype in the case of this family, despite the fact that there are no previously reported data for the Greek LQTS genetic pool. Thus, genotype-phenotype correlations are often a helpful tool in the management of LQTS patients and their families. 相似文献
62.
Relevance of Both Daily Hassles and the ALDH2 Genotype to Problem Drinking among Japanese Male Workers 总被引:1,自引:0,他引:1
Tatsuya Takeshita Soichiro Maruyama Kanehisa Morimoto 《Alcoholism, clinical and experimental research》1998,22(1):115-120
The effects of genetic polymorphisms in the ALDH2 and ADH2 genes and stress levels, as assessed by the daily hassles scale on the prevalence of problem drinkers, were investigated in males in a Japanese occupational population. The frequency of problem drinkers was estimated by the Kurihama Alcoholism Screening Test (KAST). The prevalence of those with a high KAST score (≥0.0) was significantly higher in ALDH2*1/*1 (18.4%) than in ALDH2*1/*2 (4.8%). Multiple logistic regression analysis revealed significant contributions by levels of alcohol consumption, the ALDH2 genotype, and daily hassles to the prevalence of those with a high KAST score. When we analyzed the data for each ALDH2 genotype, heavier alcohol consumption (≥28.8 ml/day), older age (≥40 years old), and very high daily hassles levels (≥20) significantly increased the prevalence of problem drinkers in ALDH2*1/*1. On the contrary, no variables other than heavier alcohol consumption influenced the prevalence in ALDH2*1/*2. In summary, the present study revealed significant contributions of both daily hassles and the ALDH2 genotype to the increase of problem drinkers in an occupational population. Health promotion activities to prevent from alcohol dependence should focus on ALDH2*1/*1 , especially those of middle age, and should include stress management as a part of their activities. 相似文献
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65.
Y.M. Chen S.H. Wu C.N. Qiu D.J. Yu X.J. Wang 《Brazilian journal of medical and biological research》2013,46(7):614-622
The objective of this study was to examine hepatitis B virus (HBV) subgenotypes
and mutations in enhancer II, basal core promoter, and precore regions of HBV in
relation to risks of liver cirrhosis (LC) and hepatocellular carcinoma (HCC) in
Southeast China. A case-control study was performed, including chronic hepatitis
B (CHB; n=125), LC (n=120), and HCC (n=136). HBV was genotyped by multiplex
polymerase chain reaction and subgenotyped by restriction fragment length
polymorphism. HBV mutations were measured by DNA sequencing. HBV genotype C
(68.2%) predominated and genotype B (30.2%) was the second most common. Of
these, C2 (67.5%) was the most prevalent subgenotype, and B2 (30.2%) ranked
second. Thirteen mutations with a frequency >5% were detected. Seven mutation
patterns (C1653T, G1719T, G1730C, T1753C, A1762T, G1764A, and G1799C) were
associated with C2, and four patterns (C1810T, A1846T, G1862T, and G1896A) were
associated with B2. Six patterns (C1653T, G1730C, T1753C, A1762T, G1764A, and
G1799C) were obviously associated with LC, and 10 patterns (C1653T, G1730C,
T1753C, A1762T, G1764A, G1799C, C1810T, A1846T, G1862T, and G1896A) were
significantly associated with HCC compared with CHB. Four patterns (C1810T,
A1846T, G1862T, and G1896A) were significantly associated with HCC compared with
LC. Multivariate regression analyses showed that HBV subgenotype C2 and
C2-associated mutation patterns (C1653T, T1753C, A1762T, and G1764A) were
independent risk factors for LC when CHB was the control, and that B2-associated
mutation patterns (C1810T, A1846T, G1862T, and G1896A) were independent risk
factors for HCC when LC was the control. 相似文献
66.
目的探讨CYP2C19、CYP3A5基因的多态性与心肌梗死发病风险的相关性。方法随机选取心肌梗死患者及健康对照各500例,采用荧光PCR法和Sanger测序分别检测其CYP2C19、CYP3A5基因的多态性,用Logistic回归分析其与心肌梗死的相关性,用Quanto软件评估统计学效能。结果CYP2C19基因rs4986893位点的AG、GG基因型和A等位基因的频率以及CYP3A5基因rs776746位点的AA、AG、GG基因型和G等位基因频率在两组之间的差异具有统计学意义(P<0.05),CYP2C19基因rs4244285、rs12248560位点的基因型和等位基因以及rs4986893位点的AA基因型的频率在两组之间差异无统计学意义(P>0.05)。在校正年龄、性别、体质指数后,Logistic回归分析显示CYP2C19基因rs4986893的AG基因型和A等位基因以及CYP3A5基因rs776746的GG基因型和G等位基因可能是心肌梗死发病的风险因素,而rs4986893的GG基因型以及rs776746的AA、AG基因型可能是心肌梗死的保护因素。依据样本量、样本结构和等位基因频率以及Quanto分析,本研究的结果具有理想的统计学效能(99%)。结论CYP2C19、CYP3A5基因的多态性可能增加心肌梗死的发病风险。 相似文献
67.
《Saudi Pharmaceutical Journal》2020,28(2):215-219
AimBreast cancer is the most common cancer and the second leading cause of cancer-related deaths among women. Several genetic and environmental factors are known to be involved in breast cancer pathogenesis, but the exact etiology of this disease is complicated and not completely understood. We aimed to investigate whether the gene polymorphisms of ABCB1 and ABCG2 carrier proteins and COX-2 enzyme affect breast cancer risk.MethodABCG2 C421A (rs2231142), ABCB1 C3435T (rs1045642), COX-2 T8473C (rs5275) and COX-2 G306C (rs5277) were genotyped 104 breast cancer patients and 90 healthy controls using a real-time PCR for breast cancer susceptibility.ResultsPatients carrying ABCG2 C421A, the CC genotype, had a higher risk of disease compared with patients carrying any A allele (OR = 3.06; 95% CI = 1.49–6.25, p = 0.0019). The other variants showed no association with breast cancer (p > 0.05). Comparing the pathological parameters with the variants, only, the frequency of C allele of ABCB1 C3435T was significantly lower in the estrogen receptor-α (ERα) (OR = 2.25; 95% CI: 0.75–6.76; p = 0.041) and progesterone receptor (PgR) (OR = 3.67; 95% CI: 1.34–10.03; p = 0.008) positive breast cancer patients.ConclusionABCB1 C3435T and ABCG2 C421A might represent a potential risk factor for breast cancer for Turkish women. 相似文献
68.
《Drug metabolism and pharmacokinetics》2020,35(2):191-200
Atomoxetine is an approved medicine for attention-deficit/hyperactivity disorder and a cytochrome P450 2D6 (CYP2D6) probe substrate. Simple physiologically based pharmacokinetic (PBPK) models and compartment models were set up to account for drug monitoring results of 33 Japanese patients (6–15 years of age) to help establish the correct dosage for the evaluation of clinical outcomes. The steady-state one-point drug monitoring data for the most participants indicated the extensive biotransformation of atomoxetine to 4-hydroxyatomoxetine under individually prescribed doses of atomoxetine. However, 5 participants (with impaired CYP2D6 activity scores based on the CYP2D6 genotypes) showed high plasma concentrations of atomoxetine (0.53–1.5 μM) compared with those of total 4-hydroxyatomoxetine (0.49–1.4 μM). Results from full PBPK models using the in-built Japanese pediatric system of software Simcyp, one-compartment models, and new simple PBPK models (using parameters that reflected the subjects' small body size and normal/reduced CYP2D6-dependent clearance) could overlay one-point measured drug/metabolite plasma concentrations from almost common 28 participants within threefold ranges. Validated one-compartment or simple PBPK models can be used to predict steady-state plasma concentrations of atomoxetine and/or its primary metabolites in Japanese pediatric patients (>6 years) who took a variety of individualized doses in a clinical setting. 相似文献
69.
载脂蛋白E基因多态性与高脂血症的相关性研究 总被引:6,自引:5,他引:6
选取133例高脂血症患者及122例正常对照人群,用多聚酶链反应方法快速鉴定其载脂蛋白E的基因型,结合血脂分析,研究载脂蛋白基因多态性与高脂血症的关系,结果表明,E3等位基因的分布频率在病例组中明显低于对照且,病例组中E4等位基因的分布频率明显高于对照组,表明E4等位基因与高脂血症显著相关。 相似文献
70.
目的探讨HBV基因型、YMDD变异与拉米夫定抗病毒治疗后HBV DNA反弹的关系。方法应用多引物对巢式PCR法、PCR-序列分析法检测拉米夫定治疗的27例乙型肝炎患者和19例从未用过抗病毒治疗的患者HBV基因型和P区(YMDD)的突变位点。结果在27例HBV DNA反弹的患者中,13例(48.15%)检出YMDD变异,而对照人群无YMDD变异(P〈0.05)。YMDD变异的位点为rtM204V/I(C区)±rtL180M(B区);在治疗组YMDD变异的患者中,B、C基因型构成比(46.15%和59.26%)与对照组(53.85%和68.42%)比较无显著性差异(P〉0.05)。结论YMDD变异是拉米夫定治疗后出现耐药导致HBV DNA反弹的主要原因;YMDD变异的常见位点依然为rtM204V/I(C区)±rtL180M(B区);YMDD变异在B、C基因型病人中无差别。 相似文献