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Vasoactive intestinal peptide (VIP) and its G protein-coupled receptors, VPAC(1)R and VPAC(2)R, are prominent in the immune system and regulate many aspects of T cell-dependent immunity. In mouse T cells, VPAC(1)R is expressed constitutively, whereas VPAC(2)R is induced by immune stimuli. VPAC(2)R-null (VPAC(2)R(-/-)) mice on a C57BL/6 background are shown here to have normal basic immune characteristics, including serum Ig concentrations, blood levels of all leukocytes, and spleen number of total T cells (CD3(+)) and T cells bearing CD4, CD8, and CD28. Hapten-evoked cutaneous delayed-type hypersensitivity (DTH) was significantly enhanced in VPAC(2)R-null mice compared with age- and sex-matched wild-type mice. In contrast, generation of IgE anti-hapten antibodies and active cutaneous anaphylaxis were > or =70% lower in VPAC(2)R-null mice than in wild-type controls. Cytokine production by splenic CD4(+) T cells, stimulated with adherent anti-CD3 plus anti-CD28 antibodies, revealed higher levels of IL-2 (mean = 3-fold) and IFN-gamma (mean = 3-fold), and lower levels of IL-4 (mean = one-fifth) in VPAC(2)R-null mice than wild-type controls. Loss of VIP-VPAC(2)R maintenance of the normal ratio of Th2/Th1 cytokines thus leads to a state of enhanced DTH and depressed immediate-type hypersensitivity, which may alter both host defense and susceptibility to immune-mediated diseases.  相似文献   
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The aim of this study was to examine how similar pregnant women with self‐reported lifetime eating disorder (ED) were to pregnant women with a hospital diagnosis of ED. A total of 83 731 pregnant women enrolled in the Danish National Birth Cohort reported on ED, and by linkage to the Danish health registers, hospital diagnoses of ED were obtained. Characteristics of women with self‐reported ED, hospital diagnosed ED and without ED were compared using chi‐square tests, t‐test and logistic regression models with robust standard errors. In total, 4.8% women reported ED, and 0.5% had a hospital diagnosis of ED recorded in the health registers. Women with self‐reported ED were comparable with women with hospital diagnosed ED on most reproductive and health characteristics, while they differed from women without ED concerning all characteristics studied. Our findings highlight that women with self‐reported ED have impaired function and adverse health outcomes, consistent with diagnosable ED. Copyright © 2016 John Wiley & Sons, Ltd and Eating Disorders Association.  相似文献   
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We examined the association between parental characteristics and disordered eating among 11‐ to 12‐year‐olds within the Danish National Birth Cohort. Frequency of fasting, purging, and binge eating was obtained by self‐report from 37,592 children and combined into a measure of disordered eating (no, monthly, and weekly). Information on parental characteristics was obtained during pregnancy, from the 7‐year follow‐up, and by linkage to population registers. Data were analysed using multinomial logistic regression models with robust standard errors. In total, 3.1% reported weekly and 4.1% reported monthly disordered eating. Parental young age, low educational level, and overweight/obesity were associated with disordered eating. The relative risk ratios for, respectively, weekly and monthly disordered eating according to maternal eating disorder were 1.01 [0.75, 1.37] and 1.09 [0.84, 1.42]. Disordered eating is common among children and is associated with several parental characteristics. We found social inequality in disordered eating, but our data did not support an association with maternal eating disorder.  相似文献   
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Background Campylobacter is one of the most frequent causes of bacterial gastroenteritis. Campylobacter outbreaks are rarely reported, which could be a reflection of a surveillance without routine molecular typing. We have previously shown that numerous small outbreak-like clusters can be detected when whole genome sequencing (WGS) data of clinical Campylobacter isolates was applied.AimTyping-based surveillance of Campylobacter infections was initiated in 2019 to enable detection of large clusters of clinical isolates and to match them to concurrent retail chicken isolates in order to react on ongoing outbreaks.MethodsWe performed WGS continuously on isolates from cases (n = 701) and chicken meat (n = 164) throughout 2019. Core genome multilocus sequence typing was used to detect clusters of clinical isolates and match them to isolates from chicken meat.ResultsSeventy-two clusters were detected, 58 small clusters (2–4 cases) and 14 large clusters (5–91 cases). One third of the clinical isolates matched isolates from chicken meat. One large cluster persisted throughout the whole year and represented 12% of all studied Campylobacter cases. This cluster type was detected in several chicken samples and was traced back to one slaughterhouse, where interventions were implemented to control the outbreak.ConclusionOur WGS-based surveillance has contributed to an improved understanding of the dynamics of the occurrence of Campylobacter strains in chicken meat and the correlation to clusters of human cases.  相似文献   
66.
D1 and D2 dopamine receptors (D1DRs and D2DRs) may contribute differently to various aspects of memory and cognition. The D1DR system has been linked to functions supported by the prefrontal cortex. By contrast, the role of the D2DR system is less clear, although it has been hypothesized that D2DRs make a specific contribution to hippocampus-based cognitive functions. Here we present results from 181 healthy adults between 64 and 68 y of age who underwent comprehensive assessment of episodic memory, working memory, and processing speed, along with MRI and D2DR assessment with [11C]raclopride and PET. Caudate D2DR availability was positively associated with episodic memory but not with working memory or speed. Whole-brain analyses further revealed a relation between hippocampal D2DR availability and episodic memory. Hippocampal and caudate D2DR availability were interrelated, and functional MRI-based resting-state functional connectivity between the ventral caudate and medial temporal cortex increased as a function of caudate D2DR availability. Collectively, these findings indicate that D2DRs make a specific contribution to hippocampus-based cognition by influencing striatal and hippocampal regions, and their interactions.Dopamine (DA) plays a key role in several cognitive processes (14). Reductions of D1 and D2 DA receptors (D1DRs and D2DRs) in aging (57) have been linked to age-related cognitive deficits (8, 9). The D1DR system has been related to functions supported by the prefrontal cortex (PFC), such as working memory and executive functions (1012), which may reflect the relatively high density of D1DRs in the PFC (13). However, the role of D2DRs is far less clear. D2DRs are present in the PFC at very low densities (13), and evidence supporting a role for the D2DR system in working memory and executive functions is elusive (10). Pharmacological (14, 15) and PET studies assessing striatal D2DR availability (or binding potential to nondisplacable tissue uptake; BPND) with [11C]raclopride (16, 17) have yielded mixed findings in relation to cognition. It has been hypothesized that D2DRs make a specific contribution to hippocampus-based cognitive functions (10, 18, 19). Supporting these claims, positive links between D2DR BPND and episodic memory are commonly observed (2023). PET imaging of hippocampal D2DR BPND also provides support for this hypothesis, although some studies indicate that hippocampal D2DRs may be related to both episodic memory and PFC-based executive functions (22, 23), including verbal working memory (24). Medial temporal lobe regions have been implicated in working memory (25, 26), and D2DR-mediated modulation may be exerted via hippocampal–cortical pathways (27). In addition, a [11C]raclopride task-activation PET study demonstrated contributions of striatal D2DRs to a verbal working-memory task (11).Taken together, the specific role of the D2DR system in cognition remains unclear, likely due to the fact that past studies included small and age-heterogeneous samples and lacked comprehensive test batteries that allowed systematic comparison of the role of D2DRs in different cognitive functions. Here we present results from the Cognition, Brain, and Aging (COBRA) study that include assessment of episodic memory, working memory, and processing speed, in combination with [11C]raclopride PET and MRI of 181 healthy adults between 64 and 68 y of age (28). The main analyses concerned caudate D2DR–cognition associations, as this striatal region has been implicated in cognitive functioning (11, 12, 29, 30). Subsequently, whole-brain analyses were conducted to examine extrastriatal (especially hippocampal) D2DRs in relation to cognition. Finally, resting-state functional connectivity patterns were analyzed in relation to D2DR BPND, with special focus on interactions between the ventral caudate (31) and medial temporal cortex regions (32, 33).  相似文献   
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Mucosal surfaces are a main entry point for pathogens and the principal sites of defense against infection. Both bacteria and phage are associated with this mucus. Here we show that phage-to-bacteria ratios were increased, relative to the adjacent environment, on all mucosal surfaces sampled, ranging from cnidarians to humans. In vitro studies of tissue culture cells with and without surface mucus demonstrated that this increase in phage abundance is mucus dependent and protects the underlying epithelium from bacterial infection. Enrichment of phage in mucus occurs via binding interactions between mucin glycoproteins and Ig-like protein domains exposed on phage capsids. In particular, phage Ig-like domains bind variable glycan residues that coat the mucin glycoprotein component of mucus. Metagenomic analysis found these Ig-like proteins present in the phages sampled from many environments, particularly from locations adjacent to mucosal surfaces. Based on these observations, we present the bacteriophage adherence to mucus model that provides a ubiquitous, but non–host-derived, immunity applicable to mucosal surfaces. The model suggests that metazoan mucosal surfaces and phage coevolve to maintain phage adherence. This benefits the metazoan host by limiting mucosal bacteria, and benefits the phage through more frequent interactions with bacterial hosts. The relationships shown here suggest a symbiotic relationship between phage and metazoan hosts that provides a previously unrecognized antimicrobial defense that actively protects mucosal surfaces.  相似文献   
70.
Clinical relevance of genetic testing is increasing in autism spectrum disorder (ASD). Information about genetic risk may contribute to improved diagnostics, treatment and family planning, but may also be perceived as a burden. Knowledge about the families’ preferences with regard to genetic risk information is important for both health care professionals and policy makers. We investigated attitudes towards sharing information about genetic risk of ASD and knowledge about future health among parent members of the Norwegian Autism Association (N = 1455) using a questionnaire, and the relationships with parent and child characteristics, such as age, gender and ASD severity. Most preferred autonomy in deciding whom to inform about genetic risk of ASD (74.4%) and a minority supported extensive intra-familial disclosure of the genetic risk (41.1%). The majority agreed that it is an obligation to know as much as possible relevant for future health (58.0%) and only 51.7% agreed to a principle of a ‘right not to know’. In regression models, the attitudes were associated with opinions about benefits and harms of genetic testing (e.g., treatment, family planning, understanding of ASD pathology, insurance discrimination and family conflict). In sum, the findings show that most parents want to know as much as possible relevant for their children’s future health and keep their autonomy and intra-familial confidentiality about genetic risk information. Nearly half of the parents were not concerned with a “right not to know”. These attitudes can inform development of guidelines and bioethics in the age of genomic precision medicine.Subject terms: Genetic counselling, Ethics, Medical ethics  相似文献   
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