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121.
Aberrant DNA methylation in the blood of patients with major depressive disorder (MDD) has been reported in several previous studies. However, no comprehensive studies using medication-free subjects with MDD have been conducted. Furthermore, the majority of these previous studies has been limited to the analysis of the CpG sites in CpG islands (CGIs) in the gene promoter regions. The main aim of the present study is to identify DNA methylation markers that distinguish patients with MDD from non-psychiatric controls. Genome-wide DNA methylation profiling of peripheral leukocytes was conducted in two set of samples, a discovery set (20 medication-free patients with MDD and 19 controls) and a replication set (12 medication-free patients with MDD and 12 controls), using Infinium HumanMethylation450 BeadChips. Significant diagnostic differences in DNA methylation were observed at 363 CpG sites in the discovery set. All of these loci demonstrated lower DNA methylation in patients with MDD than in the controls, and most of them (85.7%) were located in the CGIs in the gene promoter regions. We were able to distinguish patients with MDD from the control subjects with high accuracy in the discriminant analysis using the top DNA methylation markers. We also validated these selected DNA methylation markers in the replication set. Our results indicate that multiplex DNA methylation markers may be useful for distinguishing patients with MDD from non-psychiatric controls.  相似文献   
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In the last decades, prevalence of autism spectrum disorder (ASD) has been on the rise. However, clear aetiology is still elusive and improvements in early diagnosis are needed. To uncover possible biomarkers present in ASD, we used two‐dimensional polyacrylamide gel electrophoresis and nanoliquid chromatography‐tandem mass spectrometry (nanoLC‐MS/MS), to compare salivary proteome profiling of children with ASD and controls. A total of 889 spots were compared and only those spots with a fold change ≥1.7 and a P‐value <0.05 or a fold change of ≥3.0 between ASD cases and controls were analysed by nanoLC‐MS/MS. Alpha‐amylase, CREB‐binding protein, p532, Transferrin, Zn alpha2 glycoprotein, Zymogen granule protein 16, cystatin D and plasminogen were down‐regulated in ASD. Increased expression of proto‐oncogene Frequently rearranged in advanced T‐cell lymphomas 1 (FRAT1), Kinesin family member 14, Integrin alpha6 subunit, growth hormone regulated TBC protein 1, parotid secretory protein, Prolactin‐inducible protein precursor, Mucin‐16, Ca binding protein migration inhibitory factor‐related protein 14 (MRP14) was observed in individuals with ASD. Many of the identified proteins have previously been linked to ASD or were proposed as risk factors of ASD at the genetic level. Some others are involved in pathological pathways implicated in ASD causality such as oxidative stress, lipid and cholesterol metabolism, immune system disturbances and inflammation. These data could contribute to protein signatures for ASD presence, risk and subtypes, and advance understanding of ASD cause as well as provide novel treatment targets for ASD.  相似文献   
124.
Both otoacoustic emissions (OAEs) and auditory evoked potentials (AEPs) are sexually dimorphic, and both are believed to be influenced by prenatal androgen exposure. OAEs and AEPs were collected from people affected by 1 of 3 categories of disorders of sex development (DSD) — (1) women with complete androgen insensitivity syndrome (CAIS); (2) women with congenital adrenal hyperplasia (CAH); and (3) individuals with 46,XY DSD including prenatal androgen exposure who developed a male gender despite initial rearing as females (men with DSD). Gender identity (GI) and role (GR) were measured both retrospectively and at the time of study participation, using standardized questionnaires. The main objective of this study was to determine if patterns of OAEs and AEPs correlate with gender in people affected by DSD and in controls. A second objective was to assess if OAE and AEP patterns differed according to degrees of prenatal androgen exposure across groups. Control males, men with DSD, and women with CAH produced fewer spontaneous OAEs (SOAEs) – the male-typical pattern – than control females and women with CAIS. Additionally, the number of SOAEs produced correlated with gender development across all groups tested. Although some sex differences in AEPs were observed between control males and females, AEP measures did not correlate with gender development, nor did they vary according to degrees of prenatal androgen exposure, among people with DSD. Thus, OAEs, but not AEPs, may prove useful as bioassays for assessing early brain exposure to androgens and predicting gender development in people with DSD.  相似文献   
125.
Alternate frame folding (AFF) is a mechanism by which conformational change can be engineered into a protein. The protein structure switches from the wild‐type fold (N) to a circularly‐permuted fold (N′), or vice versa, in response to a signaling event such as ligand binding. Despite the fact that the two native states have similar structures, their interconversion involves folding and unfolding of large parts of the molecule. This rearrangement is reported by fluorescent groups whose relative proximities change as a result of the order–disorder transition. The nature of the conformational change is expected to be similar from protein to protein; thus, it may be possible to employ AFF as a general method to create optical biosensors. Toward that goal, we test basic aspects of the AFF mechanism using the AFF variant of calbindin D9k. A simple three‐state model for fold switching holds that N and N′ interconvert through the unfolded state. This model predicts that the fundamental properties of the switch—calcium binding affinity, signal response (i.e., fluorescence change upon binding), and switching rate—can be controlled by altering the relative stabilities of N and N′. We find that selectively destabilizing N or N′ changes the equilibrium properties of the switch (binding affinity and signal response) in accordance with the model. However, kinetic data indicate that the switching pathway does not require whole‐molecule unfolding. The rate is instead limited by unfolding of a portion of the protein, possibly in concert with folding of a corresponding region. Proteins 2010. © 2010 Wiley‐Liss, Inc.  相似文献   
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There is an urgent need for animal models of autism spectrum disorder (ASD) to understand the underlying pathology and facilitate development and testing of new treatments. The synaptic growth‐associated protein‐43 (GAP43) has recently been identified as an autism candidate gene of interest. Our previous studies show many brain abnormalities in mice lacking one allele for GAP43 [GAP43 (+/?)] that are consistent with the disordered connectivity theory of ASD. Thus, we hypothesized that GAP43 (+/?) mice would show at least some autistic‐like behaviors. We found that GAP43 (+/?) mice, relative to wild‐type (+/+) littermates, displayed resistance to change, consistent with one of the diagnostic criteria for ASD. GAP43 (+/?) mice also displayed stress‐induced behavioral withdrawal and anxiety, as seen in many autistic individuals. In addition, both GAP43 (+/?) mice and (+/+) littermates showed low social approach and lack of preference for social novelty, consistent with another diagnostic criterion for ASD. This low sociability is likely because of the mixed C57BL/6J 129S3/SvImJ background. We conclude that GAP43 deficiency leads to the development of a subset of autistic‐like behaviors. As these behaviors occur in a mouse that displays disordered connectivity, we propose that future anatomical and functional studies in this mouse may help uncover underlying mechanisms for these specific behaviors. Strain‐specific low sociability may be advantageous in these studies, creating a more autistic‐like environment for study of the GAP43‐mediated deficits of resistance to change and vulnerability to stress.  相似文献   
128.
目的观察国产两性霉素B抢先治疗血液病患者侵袭性肺部真菌感染(以下简称IFI)的疗效与不良反应。方法回顾性分析我院2004年12月~2008年12月间,45例免疫功能低下IFI患者接受国产两性霉素B治疗的临床资料。结果 45例患者均应用两性霉素B治疗两周以上,最长应用时间为14周,中位数6周。总有效率为86.7%,不良反应主要有低钾血症、发热、转氨酶升高、肾功损害、胃肠道反应,根据WHO药物毒性分级标准均为I~II级毒性。结论国产两性霉素B对于血液病患者IFI临床诊断的抢先治疗疗效肯定,不良反应可耐受。  相似文献   
129.
Background Children with oppositional defiant symptoms (ODS) are highly related to parental stress, especially in mothers. This study is the first to investigate the quality of life (QOL) of mothers of children with ODS in a community sample.Methods Randomly selected mothers of children attending an elementary school were contacted, and 387 who completed the questionnaire participated in this study. The children's ODS status was determined by the maternal rating of the Chinese Swanson, Nolan, and Pelham rating scale, version IV. The mothers' QOL was estimated by maternal reports from the World Health Organization Quality of Life - BREF (WHOQOL-BREF) instrument. The relationship between the children's ODS status and maternal QOL was examined by analysis of covariance (ANCOVA) with the participants' sociodemographic factors as covariables.Results Sixty-three children, mostly boys, met the screening criteria for ODS. The positive screening rate for ODS was 16.49%. The children's ODS status was a significant predictor for the maternal physical capacity, psychological wellbeing and environment domains of QOL. Mothers of children with ODS who rented a house were younger and had lower education levels and worse QOL in all domains.Conclusion A high positive screening rate for ODS children in the elementary school and a relationship between poor maternal QOL and children's ODS were found in this study. Routine screening for ODS in children and mental health services for these children and their mothers are warranted.  相似文献   
130.

BACKGROUND:

The β-thalassemia syndrome is a genetically inherited commonly encountered hematological disorder in the state of Orissa. It causes high degree of morbidity, mortality and fetal wastage in the poor vulnerable people.

AIMS AND OBJECTIVES:

There is an equal probability (50% chance) in every singleton pregnancy that a carrier parent of β-thalassemia major would either bear normal or carrier offspring, but not two offspring with carrier of β-thalassemia major genotype together. For the first time, a carrier parent of β-thalassemia major gene has born progeny (three daughters and a twin male offspring) with a carrier status of β-thalassemia major in Dudh Kharia tribal family studied from Sundargarh district of Orissa.

MATERIALS AND METHODS:

We screened randomly selected population of Dudh Kharia tribe from Sundargarh district of Orissa for hemoglobinopathies to assess the extent of the problem, design possible interventions and provide genetic counseling to them. A family with twin children was identified during screening in Lata Gaon in Bargaon block of Sundargarh district of Orissa for the above-mentioned study. Background information for this family such as name, age, sex, tribe, native place, reproductive history, family pedigree and clinical signs and symptoms were also recorded. Standardized genetic and hematological procedures and techniques were followed for analysis.

RESULTS:

Laboratory investigations for alkaline electrophoresis of blood lysate on cellulose acetate membrane showed raised hemoglobin A2 level in mother (Hb A2 = 5.3%), in three daughters (Hb A2 =6.5, 5.9, 5.5% in chronological and birth order), in two twin sons (Hb A2 =5.9% and 6.0%) and normal (Hb A2 = 3.3%) for father. Hence, all the children i.e., three daughters and two twin sons, including the mother were β-thalassemia carriers. Since all the hematological parameters i.e., red cell indices, G-6-PD enzyme activity, ABO and Rhesus blood groups and identical β-thalassemia (trait) genotypes with identical clinical manifestations and hematological profile of the twin sons under similar environmental conditions, hence they were labeled as identical monozygotic twins.

CONCLUSIONS:

It is a rare occasion when a single pregnancy carries either one or two abnormal genotypes at a time in a womb in human beings. Monozygotic twins are genetically alike and provide appraisal of the expression of identical genotype under the different environmental conditions.  相似文献   
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