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941.
The discovery of human Metapneumovirus (hMPV) and human Bocavirus (hBoV) identified the etiological causes of several cases of acute respiratory tract infections in children. This report describes the molecular epidemiology of hMPV and hBoV infections observed following viral surveillance of children hospitalized for acute respiratory tract infections in Milan, Italy. Pharyngeal swabs were collected from 240 children ≤3 years of age (130 males, 110 females; median age, 5.0 months; IQR, 2.0-12.5 months) and tested for respiratory viruses, including hMPV and hBoV, by molecular methods. hMPV-RNA and hBoV-DNA positive samples were characterized molecularly and a phylogenetical analysis was performed. PCR analysis identified 131/240 (54.6%) samples positive for at least one virus. The frequency of hMPV and hBoV infections was similar (8.3% and 12.1%, respectively). Both infections were associated with lower respiratory tract infections: hMPV was present as a single infectious agent in 7.2% of children with bronchiolitis, hBoV was associated with 18.5% of pediatric pneumonias and identified frequently as a single etiological agent. Genetically distinct hMPV and hBoV strains were identified in children examined with respiratory tract infections. Phylogenetic analysis showed an increased prevalence of hMPV genotype A (A2b sublineage) compared to genotype B (80% vs. 20%, respectively) and of the hBoV genotype St2 compared to genotype St1 (71.4% vs. 28.6%, respectively). Interestingly, a shift in hMPV infections resulting from A2 strains has been observed in recent years. In addition, the occurrence of recombination events between two hBoV strains with a breakpoint located in the VP1/VP2 region was identified.  相似文献   
942.
943.

Background

Some clinical differences between gender regarding the course and outcome of bipolar disorders have already been described and some others remain still controversial.

Aims

To explore gender differences regarding clinical and socio-demographic characteristics amongst bipolar patients with particular attention to predominant polarity and depressive symptoms.

Method

Data were collected from DSM-IV type I and II bipolar patients (n = 604), resulting from the systematic follow-up of the Bipolar Disorders Program, Hospital Clinic of Barcelona, over an average follow-up of 10 years. Socio-demographic and clinical variables were collected in order to detect gender-related differences.

Results

Bipolar women are more likely than men to show a predominance of depressive polarity as well as a depressive onset whilst men would be more likely to suffer from comorbid substance use disorders. Women significantly have a higher lifetime prevalence of psychotic depression and a higher prevalence of axis II comorbid disorders. Bipolar women are also more likely to have a family history of suicide and a lifetime history of attempted suicide. Suicide attempts are more often violent amongst bipolar men. In a backward logistic regression model, two variables were responsible for most gender-related clinical differences: type of predominant polarity - more likely to be depressive amongst women - (B = − 0.794, p = 0.027, Exp(B) = 0.452; CI =  0.223-0.915), alcohol abuse (B = − 1.095, p = 0.000, Exp(B) = 2990; CI =  1.817-4.919) and cocaine abuse (B = 0.784, p = 0.033, Exp(B) = 2.189; CI =  1.066-4.496) - more prevalent amongst men.

Conclusion

The main characteristic featuring bipolar women is depression, both at illness onset and as a predominant polarity all along the illness course. This may have important diagnostic and therapeutic implications.  相似文献   
944.
945.
Hagen C  Frizzi A  Kao J  Jia L  Huang M  Zhang Y  Huang S 《Archives of virology》2011,156(7):1209-1216
In a virus-infected plant, small interfering RNAs (siRNAs) corresponding to the viral genome form a large proportion of the small RNA population. It is possible to reassemble significant portions of the virus sequence from overlapping siRNA sequences and use these to identify the virus. We tested this technique with a resistance-breaking and a non-resistance-breaking strain of tomato spotted wilt virus (TSWV). We were able to assemble contigs covering 99% of the genomes of both viruses. The abundance of TSWV siRNAs allowed us to detect TSWV at early time points before the onset of symptoms, at levels too low for conventional detection. Combining traditional and bioinformatic detection methods, we also measured how replication of the resistance-breaking strain differed from the non-resistance-breaking strain in susceptible and resistant tomato varieties. We repeated this technique in identification of a squash-infecting geminivirus and also used it to identify an unspecified tospovirus.  相似文献   
946.
Marioni G, Staffieri A, Giacomelli L, Lionello M, Guzzardo V, Busnardo A & Blandamura S
(2011) Histopathology  58, 1148–1156
Mammalian target of rapamycin expression and laryngeal squamous cell carcinoma prognosis: novel preliminary evidence Aims: The mammalian target of rapamycin (mTOR) has a key role in regulating cancer cell proliferation, apoptosis, cell migration, and angiogenesis. The aim of this study was to assess the relationships between mTOR and clinicopathological and prognostic parameters in laryngeal squamous cell carcinoma (SCC). Methods and results: Mammalian target of rapamycin expression was determined in 103 consecutive operable laryngeal SCCs. Among the mTOR‐positive cases, the locoregional recurrence rate was higher (P = 0.048) and the disease‐free survival (DFS) rate was shorter (P = 0.031) in patients with mTOR expression >50.7%. In the N0 subgroup, the disease recurrence rate was higher (P = 0.034) and the DFS was shorter (P = 0.009) in patients with mTOR expression >50.7%. In mTOR‐positive patients, multivariate analysis showed that N stage (P = 0.0001) and mTOR status (P = 0.042) were independent indicators of a poor prognosis. Conclusions: mTOR appeared to be a significant predictor of DFS in univariate and multivariate models. mTOR expression in laryngeal SCC may be useful for the detection of patients at higher risk for recurrence, and N0 patients at higher risk for early locoregional recurrence who might benefit from more aggressive therapy. The role of mTOR inhibitors in multimodality or multitarget strategies against laryngeal SCC warrants investigation.  相似文献   
947.
Friedreich's ataxia (FRDA) is a devastating orphan disease, with no specific treatment. The disease is caused by reduced expression of the protein frataxin, which results in mitochondrial defects and oxidative damage. Levels of residual frataxin critically affect onset and progression of the disease. Understanding the molecular mechanisms that regulate frataxin stability and degradation may, therefore, be exploited for the design of effective therapeutics. Here we show that frataxin is degraded by the ubiquitin-proteasome system and that K(147) is the critical residue responsible for frataxin ubiquitination and degradation. Accordingly, a K(147)R substitution generates a more stable frataxin. We then disclose a set of lead compounds, computationally selected to target the molecular cleft harboring K(147), that can prevent frataxin ubiquitination and degradation, and increase frataxin levels in cells derived from FRDA patients. Moreover, treatment with these compounds induces substantial recovery of aconitase activity and adenosine-5'-triphosphate levels in FRDA cells. Thus, we provide evidence for the therapeutic potential of directly interfering with the frataxin degradation pathway.  相似文献   
948.
Glycosylation is the most abundant and diverse form of post-translational modification of proteins. Two types of glycans exist in glycoproteins: N-glycans and O-glycans often coexisting in the same protein. O-glycosylation is frequently found on secreted or membrane-bound mucins whose overexpression and structure alterations are associated with many types of cancer. Mucins have several cancer-associated structures, including high levels of Lewis antigens characterized by the presence of terminal fucose. The present study deals with the identification of MR signals from N-acetylgalactosamine and from fucose in HeLa cells by detecting a low-field signal in one-dimensional (1D) spectra assigned to the NH of N-acetylgalactosamine and some cross peaks assigned to fucose in two-dimensional (2D) spectra. The increase of Golgi pH by treatment with ammonium chloride allowed the N-acetylgalactosamine signal assignment to be confirmed. Behaviour of MR peak during cell growth and comparison with studies from literature taken together made it possible to have more insight into the relationship between aberrantly processed mucin and the presence of non-processed N-acetylgalactosamine residues in HeLa cells. Fucose signals, tentatively ascribed to residues bound to galactose and to N-acetylglucosamine, are visible in both intact cell and perchloric acid spectra. Signals assigned to fucose bound to galactose are more evident in ammonium chloride-treated cells where structural changes of mucin-related Lewis antigens are expected as a result of the higher Golgi pH. A common origin for the N-acetylgalactosamine and fucose resonances attributing them to aberrantly processed mucin can be inferred from the present results.  相似文献   
949.
950.
Stem cell therapy has been considered a promise for damaged myocardial tissue. We have previously shown that S-nitroso-N-acetyl-D,L-penicillamine (SNAP) increases the expression of several muscular markers and VEGF in mesenchymal stem cells, indicating that transplantation of SNAP-treated cells could provide better functional outcomes. Here, we transplanted SNAP-treated adipose tissue-derived stem cells (ADSCs) in rat infarcted myocardium. After 30 days, we observed a significant improvement of the ejection fraction in rats that received SNAP-treated ADSCs, compared with those that received untreated cells (p = 0.008). Immunohistochemical reactions showed an increased expression of troponin T–C and von Willebrand factor, and organized vascular units in the infarcted area of tissue transplanted with treated ADSCs. SNAP exposure induced intracellular S-nitrosation, a decreased GSH/GSSG ratio, but did not increase cGMP levels. Collectively, these results indicate that SNAP alters the redox environment of ADSCs, possibly associated with a pre-differentiation state, which may improve cardiac function after transplantation.  相似文献   
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