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991.
目的:探讨和研究乙型肝炎患者乙型肝炎病毒(HBV)DNA复制水平与丙氨酸氨基转移酶(ALT)水平之间的关系,为临床中乙肝患者的诊治提供参考。方法:对240例慢性乙型肝炎患者采用荧光标记定量PCR方法测定血清HBV-DNA含量,采用全自动生化分析仪测定血清ALT水平,比较和分析HBV-DNA含量与ALT水平之间的关系。结果:慢性乙肝轻、中、重度患者的HBV-DNA含量三组之间差异有统计学意义(p0.01),肝脏的损害程度与HBV-DNA含量之间具有一定的关联,等级相关系数为0.162(P=0.012);ALT水平也与HBV-DNA载量之间存在关联,等级相关系数为0.371(P0.0001)。结论:肝损伤程度与HBV-DNA含量有显著相关性;同时血清ALT水平与HBV-DNA含量呈正相关。检测血清中的HBV-DNA含量和ALT水平为指导乙肝患者HBV感染、复制、传染性的判断、治疗方案的选择和疗效评定提供有一定的依据。 相似文献
992.
Psychotic experiences are far more prevalent in the population than psychotic disorders and are associated with a wide range of depressive, anxiety and behavioral disorders, as well as increased risk for psychotic disorder. Recently, psychotic experiences have been highlighted as a potentially valuable clinical marker of risk for suicidal behavior. There have been few studies to date, however, to assess psychotic experiences as a predictor of suicidality over time. We wished to assess whether young persons with suicidal ideation at baseline assessment who reported psychotic experiences were at higher risk for persistence of suicidal ideation at follow‐up than young persons who also reported suicidal ideation at baseline but who did not report co‐occurring psychotic experiences. A total of 2,263 adolescents were assessed at age 13 to 14 years for psychotic experiences, suicidal ideation and internalizing and externalizing psychopathology. Participants were re‐assessed at ages 16 to 17 years and 19 to 20 years. Among 13‐ to 14‐year olds with suicidal ideation, co‐occurring psychotic experiences did not predict an increased odds of persistence of suicidal ideation to age 16 to 17 years (OR=0.94, 95% CI: 0.19‐4.78). Among 16‐ to 17‐year olds with suicidal ideation, however, co‐occurring psychotic experiences predicted a 6‐fold increased odds of persistence of suicidal ideation to age 19 to 20 years (OR=5.53, 95% CI: 1.33‐23.00). Psychotic experiences are an important but under‐recognized marker of risk for persistence of suicidal ideation, in particular from mid‐adolescence. An increased emphasis on the clinical assessment of psychotic experiences in mental health services should be a priority. 相似文献
993.
P. T. Goodbourn J. M. Bosten G. Bargary R. E. Hogg A. J. Lawrance‐Owen J. D. Mollon 《Genes, Brain & Behavior》2014,13(2):144-151
Deficits in sensitivity to visual stimuli of low spatial frequency and high temporal frequency (so‐called frequency‐doubled gratings) have been demonstrated both in schizophrenia and in autism spectrum disorder (ASD). Such basic perceptual functions are ideal candidates for molecular genetic study, because the underlying neural mechanisms are well characterized; but they have sometimes been overlooked in favor of cognitive and neurophysiological endophenotypes, for which neural substrates are often unknown. Here, we report a genome‐wide association study of a basic visual endophenotype associated with psychological disorder. Sensitivity to frequency‐doubled gratings was measured in 1060 healthy young adults, and analyzed for association with genotype using linear regression at 642 758 single nucleotide polymorphism (SNP) markers. A significant association (P = 7.9 × 10?9) was found with the SNP marker rs1797052, situated in the 5′‐untranslated region of PDZK1; each additional copy of the minor allele was associated with an increase in sensitivity equivalent to more than half a standard deviation. A permutation procedure, which accounts for multiple testing, showed that the association was significant at the α = 0.005 level. The region on chromosome 1q21.1 surrounding PDZK1 is an established susceptibility locus both for schizophrenia and for ASD, mirroring the common association of the visual endophenotype with the two disorders. PDZK1 interacts with N‐methyl‐d ‐aspartate receptors and neuroligins, which have been implicated in the etiologies of schizophrenia and ASD. These findings suggest that perceptual abnormalities observed in two different disorders may be linked by common genetic elements . 相似文献
994.
At the dawn of a new era in label‐free quantitation on high‐resolution MS instruments, classical methods such as iTRAQ continue to provide very useful insights in comparative proteomics. The potential to multiplex samples makes this reporter‐based labeling technique highly suited for method optimization as demonstrated here by a set of standard series. Instead of studying ratios of annotated proteins, we propose an alternative method, based on the analysis of the average reporter ratios of all the spectra from a sample or a large distinct subset herein. This strategy circumvents the bias, associated with the annotation and iTRAQ quantitation, leading to increased adequacy in measuring yield differences between workflows. As gel electrophoresis prior to MS analysis is highly beneficial, for example, as a fractionation step, the approach was applied to evaluate the influence of several parameters of the established in‐gel digestion protocol. We quantified the negative effect of SYPRO Ruby staining and the positive effect of gel fixation prior to digestion on peptide yield. Finally, we emphasize the benefits of adding CaCl2 and ACN to a tryptic in‐gel digest, resulting in an up to tenfold enhanced peptide recovery and fewer trypsin missed cleavages. 相似文献
995.
996.
《Epigenetics》2013,8(10):1322-1328
In the last years, epigenetic processes have emerged as a promising area of complex diseases research. DNA methylation measured in Long Interspersed Nucleotide Element 1 (LINE-1) sequences has been considered a surrogate marker for global genome methylation. New findings have suggested the potential involvement of epigenetic mechanisms in Type 2 diabetes (T2DM) as a crucial interface between the effects of genetic predisposition and environmental influences. Our study evaluated whether global DNA methylation predicted increased risk from T2DM or other carbohydrate metabolism disorders in a cohort study. We used a prospective cohort intervention study and a control group. We collected phenotypic, anthropometric, biochemical, and nutritional information from all subjects. Global LINE-1 DNA methylation was quantified by pyrosequencing technology. Subjects that did not improve their carbohydrate metabolism status showed lower levels of global LINE-1 DNA methylation (63.9 ± 1.7 vs. 64.7 ± 2.4) and they practiced less intense physical activity (5.8% vs. 21.5%). Logistic regression analyses showed a significant association between LINE-1 DNA methylation and metabolic status after adjustment for sex, age, BMI, and physical activity. Our study showed that lower LINE-1 DNA methylation levels were associated with a higher risk metabolic status worsening, independent of other classic risk factors. This finding highlights the potential role for epigenetic biomarkers as predictors of T2DM risk or other related metabolic disorders. 相似文献
997.
目的了解近年来我院甲真菌病病原菌的种类和构成分布情况,并研究其流行病学特点。方法收集2008年6月-2012年11月间我院皮肤科实验室甲真菌病患者病甲真菌学培养阳性的病例并进行分析。结果共收集到805例病甲真菌培养阳性的甲真菌病病例。酵母菌407株,占50.55%,皮肤癣菌385株,占47.95%,霉菌13株,占1.61%。不同年龄段的甲真菌病患者的菌属分布存在差异。结论我院近年来甲真菌病病原菌最常见为酵母菌,其次为皮肤癣菌和霉菌。年龄是影响菌属分布的重要因素。 相似文献
998.
《Expert review of proteomics》2013,10(6):819-826
Proteomics is emerging as a valuable tool in nutritional research. Proteome analysis from plasma and blood cells can identify thousands of proteins that can potentially provide valuable new biomarkers for health, reveal early indications for disease disposition, assist in dietary responders from nonresponders, and enable the discovery of mechanisms of beneficial food component effects. This review discusses the latest developments in plasma, platelet and peripheral blood mononuclear cell proteomics, specifically in the field of nutritional proteomics, including issues relating to study design, sample preparation and data interpretation. 相似文献
999.
Dr Šárka Králíková Dr Miloš Buděšínský Dr Ivan Barvík Dr Milena Masojídková Dr Zdeněk Točík Ivan Rosenberg 《Nucleosides, nucleotides & nucleic acids》2013,32(7-8):524-543
A complete series of the 2 ′–5 ′ and 3 ′–5 ′ regioisomeric types of r(ApA) and 2 ′-d(ApA) analogues with the α-hydroxy-phosphonate C3 ′-O-P-CH(OH)-C4 ″ internucleotide linkage, isopolar but non-isosteric with the phosphodiester one, were synthesized and their hybridization properties with polyU studied. Due to the chirality on the 5 ′-carbon atom of the modified internucleotide linkage bearing phosphorus and hydroxy moieties, each regioisomeric type of ApA dimer is split into epimeric pairs. To examine the role of the 5 ′-hydroxyl of the α-hydroxy-phosphonate moiety during hybridization, the appropriate r(ApA) analogues with 3 ′(2 ′)-O-P-CH2-C4 ″ linkage lacking the 5 ′-hydroxyl were synthesized. Nuclear magnetic resonance (NMR) spectroscopy study on the conformation of the modified sugar-phosphate backbone, along with the hybridization measurements, revealed remarkable differences in the stability of complexes with polyU, depending on the 5 ′-carbon atom configuration. Potential usefulness of the α-hydroxy-phosphonate linkage in modified oligoribonucleotides is discussed. 相似文献
1000.
目的:对比分析人类表皮生长因子受体2(HER-2)阳性和阴性乳腺癌X线特征,探讨乳腺癌X线征象与HER-2基因之间的相关性。方法:回顾性分析经手术病理确诊的1153例女性乳腺癌患者的X线表现,根据免疫组织化学结果分为HER-2阳性组(314例)和HER-2阴性组(839例)。对比分析两组乳腺癌肿块和钙化的X线特征,肿块主要分析形态、边界及边缘,钙化主要分析形状及分布形式,并对各项分析结果进行X2检验,P〈0.05为差异性有统计学意义。结果:HER-2阳性组乳腺癌较阴性组多表现为钙化(X2=42.528,P=0.001),HER-2阴性组乳腺癌X线表现多为单纯肿块(389/839,X2=16.374,P=0.001)。星芒状肿块在HER-2阴性组比例较高(57/514,X2=5.912,P=0.015),两组类圆形(P=0.480)、分叶状(P=0.111)、不规则形肿块(P=0.152)分布比例则无明显统计学差异。HER-2阳性组乳腺癌肿块边界多模糊不清(X2=8.319,P=0.004),阴性组肿块边界多为部分清楚(X2=5.818,P=0.016)。HER-2阳性组乳腺癌钙化形态多表现为沙砾状(X2=8.955,P=0.001)、多形性和不定形(X2=7.137,P=0.001),分布形式无明显统计学差异。结论:HER-2阳性乳腺癌X线表现钙化居多,且多为沙砾状、多形性和不定形钙化,肿块边界多模糊不清;HER-2阴性乳腺癌多表现为单纯肿块,边界多为部分清楚,星芒状肿块多见。 相似文献