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101.
Several antibiotic regimens have been proposed worldwide for empiric treatment of febrile neutropenia in children with cancer, but none of them shows clear advantages in terms of clinical efficacy. Therefore, other parameters, including drug acquisition costs, should be considered in the selection of treatment. Children receive a "fraction" of a standard daily dose, and this fraction is generally calculated on the basis of body weight; therefore, the cost of each day of therapy is determined by the packages available for each single drug. We calculated the acquisition costs of various drugs proposed for the empiric treatment of febrile neutropenia in children with cancer, and then we estimated the daily cost of therapy referred to different patient weights. In general, the combination regimen with ceftriaxone plus aminoglycoside turned out to be less expensive than other regimens (including monotherapy with third-generation cephalosporins or carbapenems).  相似文献   
102.
Single nucleotide polymorphisms (SNPs) in the T-cell receptor (TCR) gene segments might play a role in shaping the TCR repertoire. Three polymorphisms have been described for the TCRBV20S1 gene segment, one of which is responsible for a nucleotide substitution at position 524, resulting in the introduction of a stop codon. Individuals homozygous for this inactivating polymorphism ("null allele") are unable to express TCRBV20 gene products. Using DNA restriction digestion analysis, we investigated the frequency of this polymorphism in 111 healthy Sardinian subjects. Inhabitants of the Mediterranean island of Sardinia are considered to represent a genetically isolated population. Our analyses revealed an incidence of 19.8% of homozygosity for the null allele, corresponding to an allele frequency of 0.45. Such an incidence, significantly higher than the one detected in 83 non-Sardinian Caucasians (6%), is the most elevated so far reported in the literature. BV20 is a single member subfamily and the null allele produces a gap in the potential TCR repertoire. Therefore, it is possible that an undetermined selective pressure could have played a role in determining the high frequency of this inactivating polymorphism in Sardinians. Alternatively, this finding could be related to a founder effect in this ancient island population.  相似文献   
103.
In this study, we analyzed the expression and function of the lymphocyte surface lectin NKRP1A on peripheral blood monocytes (Mo) or Mo and dendritic cells (DC) derived from thymic and bone marrow precursors. De novo expression of NKRP1A and CD14 molecules was detected upon culture of CD2? CD3? CD14? CD16? CD1a? NKRP1A? immature thymic precursors for 7 days in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF). Under these culture conditions, by day 21, a fraction of cells had lost CD14 and acquired both CD80 (B7.1) and CD86 (B7.2) molecules. These cells displayed a DC-like morphology and were surface NKRP1A positive. CD34+ NKRP1A? CD14? precursors, isolated from bone marrow and cultured in the presence of GM-CSF, also expressed both NKRP1A and CD14: these antigens were newly expressed on about one third of cells which had lost the CD34 precursor marker. In addition, NKRP1A was constitutively present on resting CD14+ peripheral blood Mo. When these cells were cultured in the presence of GM-CSF, the resulting DC population retained the expression of NKRP1A and acquired CD80, while they lost the CD14 antigen. Functional analysis revealed that the engagement of NKRP1A molecule leads to a strong intracellular calcium ([Ca2+]i) increase both in resting peripheral blood Mo and in vitro-derived DC. [Ca2+]i increase was mainly due to extracellular calcium influx, as it was completely abrogated by the addition of EGTA. More importantly, the engagement of the NKRP1A molecule induced interleukin (IL)-1β and IL-12 production by resting Mo and DC, respectively. Altogether these data indicate that NKRP1A lectin is present at the surface of Mo and DC and may play a relevant role in the activation and function of both cell types.  相似文献   
104.
The interaction between receptor activator of nuclear factor-kappaB ligand (RANKL) and RANK has been reported to regulate immunity in addition to bone metabolism. The aim of this study was to determine if osteoprotegerin (OPG), an inhibitor of the RANKL-RANK interaction and possibly a new drug against osteoporosis, would adversely affect immunity. OPG was used to treat mice developing different models of cellular and humoral immune responses and also in vitro in T and B cell assays. In mice, OPG does not affect cell-mediated reactions such as contact hypersensitivity to the hapten oxazolone and liver damage, granuloma formation, and infectious load induced by mycobacterial infection. However, OPG increases humoral reactions such as the production of IgM, IgG, and IgE against the T cell dependent antigen keyhole limpet hemocyanin and the production of IgM against the T cell independent antigen Pneumovax. In vitro, OPG modestly co-stimulates T cells but does not affect the proliferation of B cells. OPG has modest immunoregulatory effects that seem to be confined to the humoral response to specific antigens.  相似文献   
105.
Hepatoblastoma (HB) is the most common liver tumor in childhood and differs in its environmental risk factors and genetic background from hepatocellular carcinoma. HB is associated with inherited conditions such as familial adenomatous polyposis and Beckwith-Wiedemann syndrome, suggesting the importance of genetic abnormalities in the pathogenesis and progression of this disease. It has a very polymorphous morphology. A diverse range of cytogenetic alterations has been reported to date, the most frequent being trisomy 2 and trisomy 20. Thirty-five HB specimens from 31 patients (22 purely epithelial, 4 purely mesenchymal, 9 mixed) were examined by comparative genomic hybridization (CGH), a technique that enables us to screen the entire tumor genome for genetic losses and gains. Our aims were as follows: (1) to characterize chromosome abnormalities that appear in this tumor and (2) to identify possible differences between different histologic subtypes of HB. We found significant gains of genetic material, with very little difference in the number and type of alterations between the different histologic components of HB. The most frequent alterations were gains of Xp (15 cases, 43%) and Xq (21 cases, 60%). This finding was also confirmed by fluorescent in situ hybridization performed on nuclei extracted from 6 specimens. Other common alterations were 1p-, 2q+, 2q-, 4q-, and 4q+. We found no difference between different histologic subtypes, a finding that may be in agreement with the hypothesis of a common clonal origin for the different components. An hitherto-unreported high frequency of X chromosome gains may support the assumption that X-linked genes are involved in the development of this neoplasm.  相似文献   
106.
The risk of adverse psychological outcomes in adult victims of childhood and adolescent sexual abuse (CSA) has been documented; however, research on possible mediating variables is still required, namely with a clinical perspective. The attachment literature suggests that secure interpersonal relationships may represent such a variable. Twenty‐eight women who had experienced episodes of CSA, and 16 control women, were interviewed using Bremner's Early Trauma Inventory and the DSM‐IV Global Assessment of Functioning; they also responded to Collins' Relationship Scales Questionnaire, evaluating adult attachment representations in terms of Closeness, Dependence and Anxiety. Subjects with an experience of severe abuse reported significantly more interpersonal distance in relationships (low index of Closeness) than other subjects. The index of psychopathological functioning was correlated with both the severity of abuse and attachment (low index of Closeness). Regression analysis on the sample of abused women revealed that attachment predicted psychopathology when abuse was controlled for, whereas abuse did not predict psychopathology when attachment was controlled for. Therefore, preserving a capacity for closeness with attachment figures in adulthood appears to mediate the consequences of CSA on subsequent psychopathological outcome. Copyright © 2009 John Wiley & Sons, Ltd. Key Practitioner Message: ? The way CSA victims deal with closeness and intimacy in relationships contributes to the quality of psychological outcome in adulthood. ? Treatment strategies for CSA victims should emphasize the enhancement of interpersonal experiences and the strengthening of the subject's sense of closeness to others, intimacy in relationships, and confidence in others.  相似文献   
107.
BACKGROUND: Abnormal levels of protein kinase A (PKA) were found in patients with bipolar disorder (BD). Since altered levels are generally accompanied by functional modifications, the purpose of this study was to investigate PKA activity in patients with BD. METHODS: PKA activity was assessed in platelets from 20 drug-free bipolar patients and 19 controls. RESULTS: The cAMP-stimulated PKA activity was significantly increased in bipolar patients compared with controls. LIMITATIONS: This study made use of platelets, which may not fully represent changes occurring in specific brain regions. CONCLUSION: This study adds to the growing evidence suggesting that abnormalities of PKA are associated with BD.  相似文献   
108.
From the second half of the eighties, the cases of tuberculosis (TBC) in Italy have been constantly increasing. The increase in TBC cases in developed countries is related to different factors, including HIV epidemic and increased number of immigrants from countries with high TBC incidence and important socio-economic problems. Compared with adults few children with TBC were homeless or coinfected with HIV, nonetheless the children lived frequently in low socioeconomic status and consequently high risk of being uninsured and with adults at risk for tuberculosis (immediate relative, household members, or recently immigrated). An epidemiologic study was carried out, in order to evaluate the impact of TBC infection in immigrant children. From January 2001 to December 2002, Mantoux test (5 IU) was performed in immigrant children hospitalized or followed in two children hospitals. They included 228 children: mean age 4 years (range 1 month to 15 years). The patients came from: South America (44%) (especially from Ecuador), from Africa (20%), from Eastern Europe (19%), (especially from Middle East and North Africa), from Far East (17%). In 30 cases (13,2%) Mantoux test was positive. Among these latter, 21 presented latent infection, whereas another 9 had tuberculous disease with pulmonary localization and one of them associated with cervical adenopathy. In the study period, among all children (4426) admitted the two Units, the prevalence of tuberculous disease was 2,5% in immigrant children compared 0.2% in native children. Accurate epidemiologic monitoring, further clinical studies aimed at highlighting TBC peculiar aspects in children, and adequate therapy can lead to TBC control in the immigrant children.  相似文献   
109.
A systematic analysis of both tumors and the surrounding urothelium to help identify what lies behind the mechanism of multifocal tumor development has not yet been performed. In this study we investigated chromosome 1, 7, 9, and 17 aneusomy in 25 superficial papillary carcinomas and in 51 tissue samples taken from sites of macroscopically uninvolved urothelium surrounding the tumors, using the fluorescence in situ hybridization method. Our data demonstrated a close genetic relationship between all examined tumors and normal-appearing mucosa. Numeric aberrations of chromosomes 1, 7, 9, and 17 were found to exhibit similar patterns in all analyzed specimens, although with different frequencies.  相似文献   
110.
A genetic link between cutaneous melanoma and thyroid cancer (TC) has been identified. A high percentage of both melanomas and papillary carcinomas of the thyroid harbors a recurrent mutation (i.e., BRAFV600E) in the BRAF oncogene. Herein, we report the case of a 65‐year‐old man with papillary TC and cutaneous malignant melanoma metastatic to masseter muscle, both characterized by BRAF mutation. This is one of the rare reports in which a complete molecular characterization has been performed. As the patients with papillary thyroid carcinoma have a higher risk of malignant melanoma and vice versa, continuous monitoring of such patients, with either of these tumors is necessary. Fine‐needle aspiration cytology is useful as shown in the present case. Diagn. Cytopathol. 2014;42:877–879. © Wiley Periodicals, Inc.  相似文献   
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