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221.

Background

Alcohol, tobacco, and illegal drug use cause considerable morbidity and mortality, but good cross-national epidemiological data are limited. This paper describes such data from the first 17 countries participating in the World Health Organization''s (WHO''s) World Mental Health (WMH) Survey Initiative.

Methods and Findings

Household surveys with a combined sample size of 85,052 were carried out in the Americas (Colombia, Mexico, United States), Europe (Belgium, France, Germany, Italy, Netherlands, Spain, Ukraine), Middle East and Africa (Israel, Lebanon, Nigeria, South Africa), Asia (Japan, People''s Republic of China), and Oceania (New Zealand). The WHO Composite International Diagnostic Interview (CIDI) was used to assess the prevalence and correlates of a wide variety of mental and substance disorders. This paper focuses on lifetime use and age of initiation of tobacco, alcohol, cannabis, and cocaine. Alcohol had been used by most in the Americas, Europe, Japan, and New Zealand, with smaller proportions in the Middle East, Africa, and China. Cannabis use in the US and New Zealand (both 42%) was far higher than in any other country. The US was also an outlier in cocaine use (16%). Males were more likely than females to have used drugs; and a sex–cohort interaction was observed, whereby not only were younger cohorts more likely to use all drugs, but the male–female gap was closing in more recent cohorts. The period of risk for drug initiation also appears to be lengthening longer into adulthood among more recent cohorts. Associations with sociodemographic variables were consistent across countries, as were the curves of incidence of lifetime use.

Conclusions

Globally, drug use is not distributed evenly and is not simply related to drug policy, since countries with stringent user-level illegal drug policies did not have lower levels of use than countries with liberal ones. Sex differences were consistently documented, but are decreasing in more recent cohorts, who also have higher levels of illegal drug use and extensions in the period of risk for initiation.  相似文献   
222.
Substance use is a major cause of disability globally. This has been recognized in the recent United Nations Sustainable Development Goals (SDGs), in which treatment coverage for substance use disorders is identified as one of the indicators. There have been no estimates of this treatment coverage cross‐nationally, making it difficult to know what is the baseline for that SDG target. Here we report data from the World Health Organization (WHO)'s World Mental Health Surveys (WMHS), based on representative community household surveys in 26 countries. We assessed the 12‐month prevalence of substance use disorders (alcohol or drug abuse/dependence); the proportion of people with these disorders who were aware that they needed treatment and who wished to receive care; the proportion of those seeking care who received it; and the proportion of such treatment that met minimal standards for treatment quality (“minimally adequate treatment”). Among the 70,880 participants, 2.6% met 12‐month criteria for substance use disorders; the prevalence was higher in upper‐middle income (3.3%) than in high‐income (2.6%) and low/lower‐middle income (2.0%) countries. Overall, 39.1% of those with 12‐month substance use disorders recognized a treatment need; this recognition was more common in high‐income (43.1%) than in upper‐middle (35.6%) and low/lower‐middle income (31.5%) countries. Among those who recognized treatment need, 61.3% made at least one visit to a service provider, and 29.5% of the latter received minimally adequate treatment exposure (35.3% in high, 20.3% in upper‐middle, and 8.6% in low/lower‐middle income countries). Overall, only 7.1% of those with past‐year substance use disorders received minimally adequate treatment: 10.3% in high income, 4.3% in upper‐middle income and 1.0% in low/lower‐middle income countries. These data suggest that only a small minority of people with substance use disorders receive even minimally adequate treatment. At least three barriers are involved: awareness/perceived treatment need, accessing treatment once a need is recognized, and compliance (on the part of both provider and client) to obtain adequate treatment. Various factors are likely to be involved in each of these three barriers, all of which need to be addressed to improve treatment coverage of substance use disorders. These data provide a baseline for the global monitoring of progress of treatment coverage for these disorders as an indicator within the SDGs.  相似文献   
223.
Neuronal calcium sensor-1 (NCS-1), a Ca(2+)-binding protein, plays an important role in the modulation of neurotransmitter release and phosphatidylinositol signaling pathway. It is known that the physiological activity of NCS-1 is governed by its myristoylation. Here, we present the role of myristoylation of NSC-1 in governing Ca(2+) binding and Ca(2+)-induced conformational changes in NCS-1 as compared with the role in the nonmyristoylated protein. The (45)Ca binding and isothermal titration calorimetric data show that myristoylation increases the degree of cooperativity; thus, the myristoylated NCS-1 binds Ca(2+) more strongly (with three Ca(2+) binding sites) than the non-myristoylated one (with two Ca(2+) binding sites). Both forms of protein show different conformational features in far-UV CD when titrated with Ca(2+). Large conformational changes were seen in the near-UV CD with more changes in the case of nonmyristoylated protein than the myristoylated one. Although the changes in the far-UV CD upon Ca(2+) binding were not seen in E120Q mutant (disabling EF-hand 3), the near-UV CD changes in conformation also were not influenced by this mutation. The difference in the binding affinity of myristoylated and non-myristoylated proteins to Ca(2+) also was reflected by Trp fluorescence. Collisional quenching by iodide showed more inaccessibility of the fluorophore in the myristoylated protein. Mg(2+)-induced changes in near-UV CD are different from Ca(2+)-induced changes, indicating ion selectivity. 8-Anilino-1-naphthalene sulfonic acid binding data showed solvation of the myristoyl group in the presence of Ca(2+), which could be attributed to the myristoyl-dependent conformational changes in NCS-1. These results suggest that myristoylation influences the protein conformation and Ca(2+) binding, which might be crucial for its physiological functions.  相似文献   
224.
During meiosis, sister chromatid cohesion is required for normal levels of homologous recombination, although how cohesion regulates exchange is not understood. Null mutations in orientation disruptor (ord) ablate arm and centromeric cohesion during Drosophila meiosis and severely reduce homologous crossovers in mutant oocytes. We show that ORD protein localizes along oocyte chromosomes during the stages in which recombination occurs. Although synaptonemal complex (SC) components initially associate with synapsed homologues in ord mutants, their localization is severely disrupted during pachytene progression, and normal tripartite SC is not visible by electron microscopy. In ord germaria, meiotic double strand breaks appear and disappear with frequency and timing indistinguishable from wild type. However, Ring chromosome recovery is dramatically reduced in ord oocytes compared with wild type, which is consistent with the model that defects in meiotic cohesion remove the constraints that normally limit recombination between sisters. We conclude that ORD activity suppresses sister chromatid exchange and stimulates inter-homologue crossovers, thereby promoting homologue bias during meiotic recombination in Drosophila.  相似文献   
225.
Kao RY  To AP  Ng LW  Tsui WH  Lee TS  Tsoi HW  Yuen KY 《FEBS letters》2004,576(3):325-330
Severe acute respiratory syndrome associated coronavirus main protease (SARS-CoV Mpro) has been proposed as a prime target for anti-SARS drug development. We have cloned and overexpressed the SARS-CoV Mpro in Escherichia coli, and purified the recombinant Mpro to homogeneity. The kinetic parameters of the recombinant SARS-CoV Mpro were characterized by high performance liquid chromatography-based assay and continuous fluorescence-based assay. Two novel small molecule inhibitors of the SARS-CoV Mpro were identified by high-throughput screening using an internally quenched fluorogenic substrate. The identified inhibitors have Ki values at low microM range with comparable anti-SARS-CoV activity in cell-based assays.  相似文献   
226.
227.
The herpes simplex virus type 1 (HSV-1) Us11 gene encodes a multifunctional double-stranded RNA (dsRNA)-binding protein that is expressed late in infection and packaged into the tegument layer of the virus particle. As a tegument component, Us11 associates with nascent capsids after its synthesis late in the infectious cycle and is delivered into newly infected cells at times prior to the expression of viral genes. Us11 is also an abundant late protein that regulates translation through its association with host components and contains overlapping nucleolar retention and nuclear export signals, allowing its accumulation in both nucleoli and the cytosol. Thus, at various times during the viral life cycle and in different intracellular compartments, Us11 has the potential to execute discrete tasks. The analysis of these functions, however, is complicated by the fact that Us11 is not essential for viral replication in cultured cells. To discover new host targets for the Us11 protein, we searched for cellular proteins that interact with Us11 and have identified PAT1 as a Us11-binding protein according to multiple, independent experimental criteria. PAT1 binds microtubules, participates in amyloid precursor protein trafficking, and has homology to the kinesin light chain (KLC) in its carboxyl terminus. The carboxyl-terminal dsRNA-binding domain of Us11, which also contains the nucleolar retention and nuclear export signals, binds PAT1, whereas 149 residues derived from the KLC homology region of PAT1 are important for binding to Us11. Both PAT1 and Us11 colocalize within a perinuclear area in transiently transfected and HSV-1-infected cells. The 149 amino acids derived from the KLC homology region are required for colocalization of the two polypeptides. Furthermore, although PAT1 normally accumulates in the nuclear compartment, Us11 expression results in the exclusion of PAT1 from the nucleus and its accumulation in the perinuclear space. Similarly, Us11 does not accumulate in the nucleoli of infected cells that overexpress PAT1. These results establish that Us11 and PAT1 can associate, resulting in an altered subcellular distribution of both polypeptides. The association between PAT1, a cellular trafficking protein with homology to KLC, and Us11, along with a recent report demonstrating an interaction between Us11 and the ubiquitous kinesin heavy chain (R. J. Diefenbach et al., J. Virol. 76:3282-3291, 2002), suggests that these associations may be important for the intracellular movement of viral components.  相似文献   
228.
RNAi for plant functional genomics   总被引:9,自引:0,他引:9  
A major challenge in the post-genome era of plant biology is to determine the functions of all the genes in the plant genome. A straightforward approach to this problem is to reduce or knock out expression of a gene with the hope of seeing a phenotype that is suggestive of its function. Insertional mutagenesis is a useful tool for this type of study, but it is limited by gene redundancy, lethal knock-outs, nontagged mutants and the inability to target the inserted element to a specific gene. RNA interference (RNAi) of plant genes, using constructs encoding self-complementary 'hairpin' RNA, largely overcomes these problems. RNAi has been used very effectively in Caenorhabditis elegans functional genomics, and resources are currently being developed for the application of RNAi to high-throughput plant functional genomics.  相似文献   
229.
BACKGROUND: Folic acid is essential for the synthesis of nucleotides and methyl transfer reactions. Folic acid-binding protein one (Folbp1) is the primary mediator of folic acid transport into murine cells. Folbp1 knockout mouse embryos die in utero with multiple malformations, including severe congenital heart defects (CHDs). Although maternal folate supplementation is believed to prevent human conotruncal heart defects, its precise role during cardiac morphogenesis remains unclear. In this study, we examined the role of folic acid on the phenotypic expression of heart defects in Folbp1 mice, mindful of the importance of neural crest cells to the formation of the conotruncus. METHODS: To determine if the Folbp1 gene participates in the commitment and differentiation of the cardiomyocytes, relative levels of dead and proliferating precursor cells in the heart were examined by flow cytometry, Western blot, and immunohistostaining. RESULTS: Our studies revealed that impaired folic acid transport results in extensive apoptosis-mediated cell death, which concentrated in the interventricular septum and truncus arteriosus, thus being anatomically restricted to the two regions of congenital heart defects. Together with a reduced proliferative capacity of the cardiomyocytes, the limited size of the available precursor cell pool may contribute to the observed cardiac defects. Notably, there is a substantial reduction in Pax-3 expression in the region of the presumptive migrating cardiac neural crest, suggesting that this cell population may be the most severely affected by the massive cell death. CONCLUSIONS: Our findings demonstrate for the first time a prominent role of the Folbp1 gene in mediating susceptibility to heart defects.  相似文献   
230.
A bacterial thermostable citrate synthase has been analyzed to investigate the structural basis of its thermostability, and to compare such features with those previously identified in archaeal citrate synthases. The gene encoding the citrate synthase from Thermus aquaticus was identified from a gene library by screening with a PCR fragment amplified from genomic DNA using a primer based on the determined N-terminal amino acid sequence and a citrate synthase consensus primer. Apart from high sequence similarities with citrate synthase sequences within the Thermus/ Deinococcus group, the analyzed enzyme has highest similarities with the enzyme from the hyperthermophilic Archaeon Pyrococcus furiosus. The recombinant enzyme is a dimer with high specific activity. Compared to its thermoactivity (T(opt)at 80 degrees C), the thermal stability of the enzyme is high, as judged from its T(m) (101 degrees C), and from irreversible thermal inactivation assays. Molecular modeling of the structure revealed an inter-subunit ion-pair network, comparable in size to the network found in the citrate synthase from P. furiosus; these networks are discussed in relation to the high thermal stability of these bacterial and archaeal enzymes.  相似文献   
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