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141.
The benign peripheral nerve sheath tumours are rare lesions mainly represented by schwannoma and neurofibroma. The present work evaluated the clinical and histopathological features of schwannomas and neurofibromas of the oral cavity diagnosed in a Brazilian population. Among 9.000 cases of oral lesions archived from 1970 to 2008, four schwannomas and 12 neurofibromas were identified, microscopically revised and immunohistochemically certified through a panel including monoclonal antibodies (anti-S100, vimentin, HHF-35 and desmin). From biopsy and histological sections records, clinical and histopathological data were retrieved, reviewed and statistically analysed. Predominantly, schwannomas affected non-white males (3:1), with an age and size averages of 34.7 years and 2.8 cm, respectively. Neurofibromas preferentially occurred on the gingival/alveolar ridge of white females (5:1), with 35.7-year mean age, peak of incidence between 3rd and 5th decade, and size average of 1.7 cm. (12 cases, 75%). The studied tumours exhibited more frequently as a painless, sessile and slow growth very similar to other oral lesions, but their microscopic features differed significantly. Schwannomas and neurofibromas are extremely uncommon in the oral cavity, exhibiting clinical features very similar but specific and peculiar microscopic findings that are useful in the establishment of the diagnosis, which in some particular cases must be confirmed by immunohistochemistry.  相似文献   
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Flagellate dermatitis, a cutaneous eruption in which the patient appears to have been whipped, has been described with antineoplastic agents and shiitake mushroom ingestion. A 15‐year‐old girl with metastatic Ewing sarcoma developed pruritic erythematous linear lesions on her trunk that became hyperpigmented over time during her first cycle of chemotherapy with doxorubicin, vincristine, cyclophosphamide, and ganitumab. Flagellate dermatitis was diagnosed based on clinical and histologic findings. Flagellate dermatitis (FD) is a rare cutaneous eruption named for its appearance, in which the patient appears to have been whipped. It has been associated with chemotherapeutic agents such as bleomycin 1 . We report FD in a child that occurred during chemotherapy treatment that included doxorubicin.  相似文献   
146.
Aims One‐eighth of young adults in the United States report that their biological father has ever been incarcerated (FEI). This study is the first to examine associations between FEI and trajectories of substance use during the transition from adolescence into young adulthood for the US population. Design Using multi‐level modeling techniques, trajectories of marijuana and other illegal drug use are examined, with FEI as the primary independent variable. Setting Data are from the first three waves of the National Longitudinal Study of Adolescent Health, a nationally representative sample of US adolescents beginning in 1995. Participants Panels of 7157 males and 7997 females followed from adolescence (7th–12th grades) into early adulthood (ages 18–27 years). Measurements Dependent variables included an ordinal measure of marijuana frequency of use in last thirty days, and a dichotomous measure for whether respondent had any use in the last thirty days of illegal drugs such crystal meth, cocaine, heroin, hallucinogens, PCP, LSD, speed, and ecstasy. Findings Among males and females, respectively, FEI is associated with an increased frequency of marijuana use, and increased odds of any other illegal drug use. Interactions between FEI and age further reveal that FEI is associated with an accentuated trajectory (i.e. a steeper slope) of marijuana use, and an elevated risk (i.e. higher mean level) of other illegal drug use. Conclusions Analysis provides some of the first evidence that paternal incarceration is significantly associated with drug use among U.S. males and females, even after controlling for a number of family background, parental, and individual characteristics.  相似文献   
147.
To maintain positive health outcomes over the life course, prevention efforts should begin early in childhood. Two research domains that significantly impact the trajectory of health over the life course are childhood obesity and early trauma and violence. Prevention strategies addressing multiple levels of influence are being adopted in these fields. Childhood obesity prevention efforts no longer focus solely on individuals, but embrace multiple ecological levels, such as family, school, and community. Similarly, research on early trauma and violence has broadened to consider risk and protective factors across domains of influence. Although we have improved our understanding and prevention of these two issues, gaps remain in research, practice, and policy. The purpose of this review is to relay relevant findings that could enhance prevention strategies. We describe early life and multilevel risk factors relevant to these areas of research. We also provide recommendations for future efforts to better ensure good health for generations to come.  相似文献   
148.
Bristow CL  Mercatante DR  Kole R 《Blood》2003,102(13):4479-4486
Human leukocyte elastase (HLE) interacts with HIV-1 glycoprotein (gp)41, suggesting a nonenzymatic receptor function for HLE in the context of HIV-1. HLE is found localized to the cell surface, but not granules in HIV permissive clones, and to granules, but not the cell surface of HIV nonpermissive clones. Inducing cell-surface HLE expression on HLE null, HIV nonpermissive clones permits HIV infectivity. HIV binding and infectivity diminish in proportion to HLE RNA subtraction. HIV binding and infectivity show dose dependence for the natural HLE ligand alpha1 proteinase inhibitor (alpha1antitrypsin, alpha1PI). Chemokines prevent, whereas alpha1PI promotes, copatching of HLE with the canonical HIV receptors. Recent demonstration that decreased viral RNA is significantly correlated with decreased circulating alpha1PI in HIV seropositive individuals is consistent with a model in which HLE and alpha1PI can serve as HIV coreceptor and cofactor, respectively, and potentially participate in the pathophysiology of HIV disease progression.  相似文献   
149.
We describe the clinical features of 28 patients with juvenile dermatomyositis (JDM) and 1 patient with adult-onset dermatomyositis (DM), all of whom developed lipodystrophy (LD) that could be categorized into 1 of 3 phenotypes, generalized, partial, or focal, based on the pattern of fat loss distribution. LD onset was often delayed, beginning a median of 4.6 years after diagnosis of DM. Calcinosis, muscle atrophy, joint contractures, and facial rash were DM disease features found to be associated with LD. Panniculitis was associated with focal lipoatrophy while the anti-p155 autoantibody, a newly described myositis-associated autoantibody, was more associated with generalized LD. Specific LD features such as acanthosis nigricans, hirsutism, fat redistribution, and steatosis/nonalcoholic steatohepatitis were frequent in patients with LD, in a gradient of frequency and severity among the 3 sub-phenotypes. Metabolic studies frequently revealed insulin resistance and hypertriglyceridemia in patients with generalized and partial LD. Regional fat loss from the thighs, with relative sparing of fat loss from the medial thighs, was more frequent in generalized than in partial LD and absent from DM patients without LD. Cytokine polymorphisms, the C3 nephritic factor, insulin receptor antibodies, and lamin mutations did not appear to play a pathogenic role in the development of LD in our patients. LD is an under-recognized sequela of JDM, and certain DM patients with a severe, prolonged clinical course and a high frequency of calcinosis appear to be at greater risk for the development of this complication. High-risk JDM patients should be screened for metabolic abnormalities, which are common in generalized and partial LD and result in much of the LD-associated morbidity. Further study is warranted to investigate the pathogenesis of acquired LD in patients with DM.  相似文献   
150.
All-trans retinoic acid (ATRA) and retinoid derivatives are essential agents for multiple biological processes. Numerous immune system dysfunctions can occur in the case of retinoid deficiency. Because of the central role of dendritic cells (DCs) in controlling immunity and the wide effects of retinoids on the immune system homeostasis, we investigated the ability of ATRA to influence the differentiation of DCs from circulating peripheral blood monocytes. Human peripheral blood monocytes were cultured with granulocyte-macrophage colony-stimulating factor (GM-CSF) and various concentrations of ATRA. Differentiated cells were assayed for their morphology, phenotype, antigen uptake, allostimulatory capacity and cytokine secretion profile. ATRA (10(-12) mol/l) and GM-CSF drove the differentiation of monocytes into dendritic-like cells (ATRA-DC). ATRA-DCs exhibited DC morphology, had a phenotype of immature DCs, with the expression of CD1a, and upregulation of adhesion and co-stimulatory molecules. ATRA-DCs could induce a proliferative response in naive CD4+ T cells. Although ATRA-DCs retained their antigen-capture capacity, they secreted interleukin (IL)-12p70 without the need for any maturation agent. In addition, ATRA-DCs could drive T cells towards an IL-12-dependent T-helper cell type 1 response with secretion of interferon-gamma. DCs appear to be potential targets for ATRA, giving new insights into the immunomodulatory function of retinoids, with implications potentially related to immunotherapy.  相似文献   
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