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Background:  Epidermal squamous cell carcinoma (SCC) is a common malignancy in Pakistan. We hypothesize that it is characterized by higher frequency of p53 genetic mutations and increased AgNOR values compared with squamous cell papilloma (SCP) and basal cell carcinoma (BCC).
Experimental design: To test our hypothesis, 140 skin biopsies (including 20 normal skin, 20 SCP, 20 BCC and 80 SCC samples of various grades) were examined for p53 mutations using immunohistochemistry (IHC) and polymerase chain reaction (PCR). AgNOR staining was used for histological determination of AgNOR index.
Results:  Both markers were undetectable in normal skin and were low in SCP. They were upregulated in BCC and SCC. PCR experiments revealed p53 mutations in 70% and 96.25% of BCC and SCC, respectively. Higher AgNOR values were seen in SCC than in BCC (mean AgNOR count = 5.81 ± 31 and 8.36 ± 19; percentage of AgNOR was 43.5% and 53% in BCC and SCC, respectively). Finally, p53 IHC score was found to be related to the AgNOR index in the histological grading of BCC and SCC (r = +0.983, p < 0.0001).
Conclusion:  Our results suggest that a higher frequency of p53 genetic mutations and increased AgNOR values exist in SCC compared with BCC and SCP. 'Consequently, SCC patients may have poorer prognosis'.  相似文献   
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The genus Mentha comprises several aromatic species, which are cultivated world‐over due to their distinct aroma and commercial value. In addition to traditional food flavoring uses, Mentha are well recognized for their folk medicinal uses, especially to treat cold, fever, and digestive and cardiovascular disorders. A number of biological activities such as antioxidant, antimicrobial, biopesticidal, antitumor, anticancer, antiviral, antiallergic, antiinflammatory, antihypertensive, and urease inhibitory activity have been ascribed to Mentha. The traditional pharmacological attributes of Mentha herbs can be linked to the occurrence of bioactive phytochemicals such as terpenoids, alcohols, rosmarinic acid, and antioxidant phenolics among others. A rich source of bioactives, different species of Mentha, can be explored as a promising candidate for the development of nutra‐pharmaceuticals. This review covers the nutritional, phytochemical, and traditional medicinal aspects and multiple biological activities of some commonly available species of Mentha so as to explore their potential applications for nutra‐pharmaceutical and cosmo‐nutraceutical industry. Detailed chemical profile and pharmaceutical attributes of various Mentha essential oils are also covered. Moreover, based on computational analysis, quantitative chemical component–antioxidant activity relationship model is reviewed to predict and correlate structure–activity relationship of potential bioactives in selected Mentha essential oils leading to discovery and developmenmt of novel natural drugs.  相似文献   
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Purpose: Spinal bronchogenic cysts (SBCs) are rare congenital lesions. The clinical and imaging characteristics and treatment of SBCs are not well known. We studied three cases of SBCs retrospectively, which were registered in our department and analyzed eight case reports which were all published in English, focusing on providing a deeper knowledge of SBCs.

Methods: Three patients with SBCs registered in our department were retrospectively reviewed. Eight reported SBCs cases published from 1992 to 2015 were enrolled in our study. Imaging diagnosis was confirmed by computed tomography (CT), MRI, and computed tomography angiography (CTA). All of our patients and reviewed cases had undergone surgical resection and the final diagnosis was made by pathological examination.

Results: Five lesions were located at the cervical spinal canal. Most patients presented with pain in the limbs and back, which might be related to compression of the spinal cord and the reduced blood supply of the anterior spinal artery. The signal intensity on MRI was correlated with cystic fluid traits to a large extent. Seven lesions were partially removed because of the adhesions to the nearby spinal cord. All reported cases had no recurrence in the later follow-up.

Conclusions: SBCs can occur anywhere in the spinal canal, but they are more likely to present at the cervical canal and might be present along with some developmental malformations of the spine. We emphasize the role of CT and MRI findings in the disease diagnosis. It is recommended that the lesion should be removed as completely as possible.  相似文献   

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The present study was designed to investigate whether Khamira Abresham Hakim Arshad Wala (KAHAW), a preparation of Unani System of Medicine, is able to attenuate the isoproterenol (ISO)-induced myocardial necrosis on the basis of its effects on hemodynamic, antioxidant, histopathological and ultrastructural parameters. Male Wistar albino rats were administered KAHAW (200, 400 and 800 mg/kg/day, orally) or vehicle for 14 days with concurrent ISO administration (85 mg/kg, subcutaneously, 2 doses at 24 h interval) on 13th and 14th day. On the 15th day, vehicle+ISO-treated rats exhibit cardiac dysfunctions as indicated by decrease in systolic, diastolic, and mean arterial pressures, reduction in both maximum positive and maximum negative rates of developed left ventricular pressure (±LVdp/dt) and an increase in left ventricular end-diastolic pressure (LVEDP). Biochemical analysis of their heart homogenate presented reduced levels of enzymes viz., superoxide dismutase (SOD), catalase (CAT), lactate dehydrogenase (LDH), creatine kinase-MB (CK-MB) isoenzyme. A marked reduction in reduced glutathione (GSH) levels along with increase in levels of thiobarbituric acid reactive substances (TBARS) was also observed in rat myocardium. Myocardial necrosis, edema and inflammation were evident from the light microscopic and ultrastructural changes. KAHAW at dose of 800 mg/kg/day significantly reversed majority of hemodynamic and antioxidant derangements. The protective role of KAHAW on ISO-induced myocardial necrosis was further confirmed by histopathological and ultrastructural examination. There was no significant change in heart rate in all experimental groups. KAHAW per se groups showed no significant change when compared with vehicle control group. The study results thus demonstrated the cardioprotective potential of KAHAW against ISO-induced myocardial necrosis and associated oxidative stress.  相似文献   
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The defective insulin production is associated with severely reduced islet cell mass leading to diabetes. Growth factors preconditioned stem cells have arisen as an effective therapy to treat many diseases including diabetes. The current study was designed to assess the effect of pretreatment of ASCs derived IPCs with combination of stromal cell derived factor 1 alpha (SDF1α) and basic fibroblast growth factor (bFGF) in improving glucose tolerance in streptozotocin induced diabetic rats. The results showed maximally significant reduction in hyperglycaemia and fibrosis, while up-regulation of survival and pancreas-specific genes, insulin levels and homing of transplanted cells in SDF-1α?+?bFGF IPCs transplanted rats as compared with other groups. Moreover, increased expression of insulin, glucagon and Glut-2 in pancreas of the SDF-1α?+?bFGF IPCs transplanted group indicated more regeneration of pancreas. Hence, the use of IPCs preconditioned with SDF-1α?+?bFGF would be more effective for treating diabetes.  相似文献   
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