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51.
We describe a 59-year-old woman with sick sinus syndrome (SSS) and arrhythmogenic right ventricular cardiomyopathy (ARVC). Diagnosis of SSS was made because she had frequent episodes of sinus arrest with prolonged ventricular asystole. Cardiac images showed a dilated right atrium (RA) and a right ventricle (RV). Electroanatomical mapping of the RA showed extensive scarring with no recordable electrical potentials. Although she had frequent premature ventricular contractions, neither spontaneous ventricular tachycardia (VT) nor induced VT was observed. Microscopic examination of the RV indicated fibrofatty myocardium. Atrial arrhythmias associated with SSS may be the cause of symptoms in some cases of ARVC.  相似文献   
52.
Type I interferons (IFN-αβ) are immunoregulatory cytokines that promote both innate and adaptive immune responses. Although they have been implicated in human SLE, recent studies in mice have helped solidify this connection. By using lupus-prone mice with knockout of the IFN-αβ receptor, we and others have documented that lack of IFN-αβ leads to a marked reduction in disease manifestations, including autoantibody production, target organ damage and mortality. Furthermore, IFN-αβ was found to potentially contribute to several levels of disease pathogenesis. These included the differentiation and activation of dendritic cells, the activation and proliferation of T cells, T cell survival and the activation and survival of autoantibody-producing B cells. These findings strongly support the targeting of IFN-αβ in SLE and suggest that definition of the specific pathways critical for disease induction will be important for optimal intervention.  相似文献   
53.
Atypical lipomatous tumor or well-differentiated liposarcoma/dedifferentiated liposarcoma (DDLPS) is the most frequent subtype of malignant adipocytic tumor. This tumor typically presents in late adult life, most commonly in the retroperitoneum, extremities, or spermatic cord. It has been reported that the dedifferentiated component consists mainly of high-grade sarcoma, including undifferentiated pleomorphic sarcoma, fibrosarcoma, and myxofibrosarcoma, and it has been recently reported that the dedifferentiated component can be also made up of a low-grade sarcomatous component. Therefore, the dedifferentiated areas exhibit a wide morphological spectrum that commonly includes fibroblastic/myofibroblastic and fibrohistiocytic tumors but very rarely includes vascular tumors. We present here the first reported case of DDLPS with a hemangioendothelioma-like component in the spermatic cord.  相似文献   
54.
Lysophosphatidylinositol acyltransferase 1 (LPIAT1), also known as MBOAT7, is a phospholipid acyltransferase that selectively incorporates arachidonic acid (AA) into the sn‐2 position of phosphatidylinositol (PI). We previously demonstrated that LPIAT1 regulates AA content in PI and plays a crucial role in brain development in mice. However, how LPIAT1 is regulated and which proteins function cooperatively with LPIAT1 are unknown. In this study, using a split‐ubiquitin membrane yeast two‐hybrid system, we identified the small subunit of serine palmitoyltransferase a (ssSPTa) as an LPIAT1‐interacting protein. ssSPTa co‐immunoprecipitated and colocalized with LPIAT1 in cultured mammalian cells. Knockdown of ssSPTa decreased the LPIAT1‐dependent incorporation of exogenous AA into PI but did not affect the in vitro enzyme activity of LPIAT1 in the microsomal fraction. Interestingly, knockdown of ssSPTa decreased the protein level of LPIAT1 in the crude mitochondrial fraction but not in total homogenate or the microsomal fraction. LPIAT1 was localized to the mitochondria‐associated membrane (MAM), where AA‐selective acyl‐CoA synthetase is enriched. These results suggest that ssSPTa plays a role in fatty acid remodeling of PI, probably by facilitating the MAM localization of LPIAT1.  相似文献   
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The purpose of this study was to determine the differences in hepatic circulation and oxygen consumption in two groups: those with nonalcoholic obesity-related fatty live and those with alcoholic fatty liver. Although the histological degree of fatty infiltration was equal in the two groups, the delta Er569-650, as an index of the regional liver blood flow estimated by spectrophotometric method, was significantly lower in alcoholic fatty liver than in nonalcoholic fatty liver, and the in vivo hepatic oxygen consumption (VO2), also determined by hepatic reflectance spectrophotometry during peritoneoscopy, tended to be lower in alcoholic fatty liver than in nonalcoholic fatty liver. The oxygen saturation of hemoglobin in local liver blood (SO2) was, however, significantly higher in alcoholic fatty liver than in nonalcoholic fatty liver. These results suggest that an increase in oxygen extraction to maintain oxygen consumption, which was indicated by the lowering of the SO2, was not found in alcoholic fatty liver, in spite of a reduction of oxygen supply to the liver. It is concluded that the impairment of hepatic circulation and hepatic oxygen consumption was more serious in alcoholic fatty liver than in nonalcoholic fatty liver, possibly contributing to a different prognosis for the two forms of fatty liver.  相似文献   
58.

Background

Little has been reported about protocol-driven outpatient palliative care consultation (OPCC) for advanced heart failure (HF).

Objectives

To describe evaluation practices and treatment recommendations made during protocol-driven OPCCs for advanced HF.

Methods

We performed content analysis of OPCCs completed as part of ENABLE CHF-PC, an early palliative care HF intervention, conducted at sites in the Northeast and Southeast. T-tests, Fisher's exact, and Chi-square tests were used to evaluate sociodemographic, outcome measures, and site content differences.

Results

Of 61 ENABLE CHF-PC participants, 39 (64%) had an OPCC (Northeast, n=27; Southeast, n=12). Social and medical history assessed most were close relationships (n=35, 90%), family support (n=33, 85%), advance directive status (n=33, 85%), functional status (n=30, 77%); and symptoms were mood (n= 35, 90%), breathlessness (n=28, 72%), and chest pain (n=24, 62%). Treatment recommendations focused on care coordination (n=13, 33%) and specialty referrals (n=12, 31%). Between-site OPCC differences included assessment of family support (Northeast vs. Southeast: 100% vs. 50%), code status (96% vs. 58%), goals of care discussions (89% vs. 41.7%), and prognosis understanding (85% vs. 33%).

Conclusion

OPCCs for HF focused on evaluating medical and social history, along with goals of care and code status discussions. Symptom evaluation commonly included mood disorders, pain, dyspnea, and fatigue. Notable regional differences were found in topics evaluated and OPCC completion rates.  相似文献   
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Background: Valproic acid (VPA) has been used to treat epilepsy and bipolar disorder. Several reports have demonstrated that VPA functions as a histone deacetylase (HDAC) inhibitor. While VPA is known to cause teratogenic changes in the embryonic zebrafish brain, its effects on neural stem cells (NSCs) in both the embryonic and adult zebrafish are not well understood. Results: In this study, we observed a proliferative effect of VPA on NSCs in the embryonic hindbrain. In contrast, VPA reduced cell proliferation in the adult zebrafish optic tectum. Treatment with HDAC inhibitors showed a similar inhibitory effect on cell proliferation in the adult zebrafish optic tectum, suggesting that VPA reduces cell proliferation through HDAC inhibition. Cell cycle progression was also suppressed in the optic tectum of the adult zebrafish brain because of HDAC inhibition. Recent studies have demonstrated that HDAC inhibits the Notch signaling pathway; hence, adult zebrafish were treated with a Notch inhibitor. This increased the number of proliferating cells in the adult zebrafish optic tectum with down‐regulated expression of her4, a target of Notch signaling. Conclusions: These results suggest that VPA inhibits HDAC activity and upregulates Notch signaling to reduce cell proliferation in the optic tectum of adult zebrafish. Developmental Dynamics 243:1401–1415, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
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