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141.
Gliomas are the most common primary intracranial tumor, representing 81% of malignant brain tumors. Although relatively rare, they cause significant mortality and morbidity. Glioblastoma, the most common glioma histology (∼45% of all gliomas), has a 5-year relative survival of ∼5%. A small portion of these tumors are caused by Mendelian disorders, including neurofibromatosis, tuberous sclerosis, and Li-Fraumeni syndrome. Genomic analyses of glioma have also produced new evidence about risk and prognosis. Recently discovered biomarkers that indicate improved survival include O6-methylguanine-DNA methyltransferase methylation, isocitrate dehydrogenase mutation, and a glioma cytosine–phosphate–guanine island methylator phenotype. Genome-wide association studies have identified heritable risk alleles within 7 genes that are associated with increased risk of glioma. Many risk factors have been examined as potential contributors to glioma risk. Most significantly, these include an increase in risk by exposure to ionizing radiation and a decrease in risk by history of allergies or atopic disease(s). The potential influence of occupational exposures and cellular phones has also been examined, with inconclusive results. We provide a “state of the science” review of current research into causes and risk factors for gliomas in adults.  相似文献   
142.
The subunit stoichiometry of heteromeric glycine-gated channels determines fundamental properties of these key inhibitory neurotransmitter receptors; however, the ratio of α1- to β-subunits per receptor remains controversial. We used single-molecule imaging and stepwise photobleaching in Xenopus oocytes to directly determine the subunit stoichiometry of a glycine receptor to be 3α1:2β. This approach allowed us to determine the receptor stoichiometry in mixed populations consisting of both heteromeric and homomeric channels, additionally revealing the quantitative proportions for the two populations.  相似文献   
143.
Yuksekkaya H  Ozbek O  Keser M  Toy H 《Pediatrics》2012,129(4):e1080-e1084
Blue rubber bleb nevus syndrome (BRBNS) is a rare disorder with characteristic vascular malformations of the skin, gastrointestinal system, and, less often, other organ systems. The characteristic cutaneous lesions consist of deep-blue, soft, rubbery blebs, which are easily compressible. The most serious complication is abundant gastrointestinal bleeding. We describe the case of an 8-year-old girl with diagnosed BRBNS who had multiple venous malformations all over her body, importantly, throughout the gastrointestinal tract, mouth, esophagus, stomach, small bowel, and colon. She presented with recurrent massive gastrointestinal bleeding and soft tissue hematoma despite prednisolone and α-interferon therapy. We started low-dose sirolimus as an antiangiogenic agent. The vascular masses were reduced rapidly and there was no gastrointestinal bleeding and muscular hematoma after sirolimus therapy. There was no drug adverse reaction at 20-month follow-up. To the best of our knowledge, this is the first report related to the use of sirolimus in a patient with BRBNS.  相似文献   
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Background The significance of vascular endothelial growth factor (VEGF) and heat shock protein-90 (HSP90) has received only limited attention especially in acute lymphoblastic leukemia (ALL). In this study, we assessed expressions of HSP90 and VEGF in bone marrow samples of patients with ALL and effect of these expression quantities on the mean overall survival. Patients and methods Using immunohistochemical methods, we assessed expression of HSP90 and VEGF in 22 cases of ALL. Results Expression of HSP90 was detected in 19/22 (86.4%) and 3/22 (13.6%) of patients with ALL, for strongly positive and moderate-weakly positive, respectively. Negative HSP90 expression was not detected in patients with ALL. Expression of HSP90 in patients with ALL and in control group were statistically significant (P < 0.001), however, did not reflect the mean overall survival (P = 0.910). Mean OS was evaluated 992 ± 181 and 724.8 ± 88.2 days for moderate-weak and high HSP90 expression, respectively. VEGF expressions were not significantly different between ALL and control groups (P < 0.087). We did not find any relationship between HSP90 and VEGF expressions in bone marrow specimens of patients with ALL. Conclusion This study demonstrated that HSP90 expression grades in patients with ALL were significantly higher than that in controls and presence of strong HSP90 expression was associated with worse overall survival. VEGF expression in patients with ALL was not different from that in control samples. Determination HSP90 with immunohistochemical method in bone marrow can provide information about prognosis.  相似文献   
146.
With improved survival after liver transplantation (LT), the referral of older candidates has increased. The increasing demand for, and the decreased supply of, liver donors makes careful preoperative cardiac risk assessment imperative. There is a paucity of information regarding the cardiac characteristics of patients being referred for LT in the current era. This study aimed to describe the cardiac hemodynamic and coronary angiographic characteristics of a cohort of patients with end-stage liver disease without known coronary artery disease (CAD) being evaluated for LT. One hundred sixty-one consecutive patients aged>or=45 years with end-stage liver disease who were referred for right- and left-sided cardiac catheterization as part of a liver transplant evaluation were identified. There was a high prevalence of atherosclerotic risk factors; half had hypertension or diabetes, and more than half had >or=2 coronary risk factors other than age. There was a high prevalence of CAD, with 26% having unknown moderate to severe coronary narrowing. Patients with moderate to severe CAD were older, were more likely to be men, and were more likely to have hypertension or diabetes mellitus. Right- and left-sided filling pressures were elevated, suggesting abnormalities in left ventricular diastolic compliance. In conclusion, this study showed a high prevalence of coronary risk factors and unknown moderate to severe CAD in patients with end-stage liver disease being referred for LT.  相似文献   
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148.

Background  

To assess the intra-examiner repeatability and agreement of corneal pachymetry maps measured by time-domain (Visante OCT) and Fourier-domain optical coherence tomography (RTVue OCT).  相似文献   
149.
Skin diseases are considered to be common in Nyala, Sudan. This study was carried out to verify the prevalence of skin diseases in Nyala. This prospective observational study included skin examination of a total of 1802 people: 620 patients who were evaluated in the outpatient clinics (OC) and 1182 people from orphanages and refugee camps (ORC) in Nyala, Sudan. χ2 test was used. The total prevalence of skin disorders in the sample was 92.6% (1670/1802). One thousand and fifty of 1182 (88.8%) people from ORC had a skin disorder. The most common skin diseases in this community were: fungal infections (32.6%), dermatitis/eczema (10.5%), bacterial skin infections (10.3%), disorders of skin appendages (8.7%), parasitic infestations (7.7%), atrophic skin disorders (7.4%), disorders of pigmentation (7.4%), hypertrophic skin disorders (6.4%), viral infections (5.8), benign neoplasm (1.9%), dermatoses due to animal injury (0.4%), bullous dermatoses (0.1%), and malignant neoplasm (0.1%). Hypertrophic and atrophic disorders of the skin were mainly lesions of scarification (mostly atrophic) (5.7%) and keloids (5.6%). Fungal infection, bacterial infection, and parasitic infestation were more common in the ORC group, while dermatitis and eczema, disorders of skin appendages, hypertrophic and atrophic disorders of the skin, disorders of pigmentation, and benign neoplasm were more common in the OC group. The prevalence of skin diseases in the rural Nyala was more than our expectation and was dominated by infectious skin diseases. In addition, infectious skin diseases were more common in ORC rather than OC.  相似文献   
150.
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