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61.
62.
The hepatoprotective activity of the 50% ethanol extract of the bark of Lawsonia alba syn. L. inermis was investigated against the carbon tetrachloride-induced oxidative stress. Pretreatment of rats with doses of 250 and 500 mg/kg of the plant extract significantly (P < 0.001) lowered serum transaminases (GOT and GPT) and LDH levels, respectively, in a dose dependent manner against the significant (P < 0.001) rise of these damage marker enzymes when challenged with CCl4 (1 ml/kg, orally). Parallel to these changes, the plant extract prevented CCl4-induced oxidative stress by significantly maintaining the levels of reduced glutathione (GSH), its metabolizing enzymes and simultaneously inhibiting the production of free radicals. Pretreatment of rats with the extract also inhibited the peroxidation of microsomal lipids in a dose-dependent manner.  相似文献   
63.
We report a case of cardiac tamponade in whom speedy diagnosis and immediate drainage of pericardial blood helped to save the life of a patient with ascending aortic dissection. This report illustrates the importance of physical proximity of radiologic services to the emergency department and availability of appropriately trained radiologists.  相似文献   
64.
Cadmium intoxication induces lipid peroxidation and causes oxidative damage to various tissues by altering antioxidant defence system enzymes. At 24 h after treatment with a single intraperitoneal dose of cadmium chloride (5 mg kg-1), Swiss albino mice showed a significant increase in the levels of malanodialdehyde and xanthine oxidase (P<0.001), and a concomitant depletion of renal glutathione, catalase (P<0.001) and other antioxidant enzymes. CdCl2 also led to a simultaneous increase in micronuclei formation (P<0.001) and chromosomal aberrations (P<0.05) in mouse bone marrow cells. Oral pre-treatment with Pluchea lanceolata extract at doses of 100 and 200 mg kg-1 for 7 consecutive days before CdCl2 intoxication caused a significant reduction in malanodialdehyde formation and xanthine oxidase activity (P<0.001). A significant restoration of the activity of antioxidant defence system enzymes such as catalase, glutathione peroxidase (P<0.05), glutathione-S-transferase and glutathione reductase (P<0.001) was observed. A significant dose-dependent decrease in chromosomal aberrations and micronuclei formation was also observed (P<0.05). The results indicate that pre-treatment with P. lanceolata attenuates cadmium chloride induced oxidative stress and genotoxicity by altering antioxidant enzymes and reducing chromatid breaks and micronuclei formation.  相似文献   
65.
66.
Systolic hypertension in older persons   总被引:10,自引:1,他引:9  
Chaudhry SI  Krumholz HM  Foody JM 《JAMA》2004,292(9):1074-1080
Context  The Seventh Report of the Joint National Committee on Prevention, Detection, Evaluation, and Treatment of High Blood Pressure emphasizes the importance of systolic hypertension (SH), defined as systolic blood pressure (SBP) of at least 140 mm Hg and diastolic blood pressure of less than 90 mm Hg, in older persons (60 years). Objective  To systematically review the literature on clinical management of SH in older persons. Data Sources  We performed a MEDLINE search of English-language literature from 1966-2004 to identify reports about SH in older persons, with particular emphasis on data from randomized clinical trials. Study Selection and Data Extraction  We selected 1064 studies by using the search terms hypertension combined with the terms systole (or systolic) and aged. Data Synthesis  There is strong evidence from clinical trials to support the treatment of SH in older persons with SBP of at least 160 mm Hg. Large-scale trials to assess the value of antihypertensive therapy for older patients with SBP of 140 to 159 mm Hg have not been performed, and recommendations to treat these patients are based on observational studies that show a graded relationship of cardiovascular risk with increasing SBP. The studies most strongly support the use of thiazide diuretics and long-acting calcium channel blockers as first-line therapy to treat SH. Conclusions  Treatment of SH in older patients with SBP of at least 160 mm Hg is supported by strong evidence. The evidence available to support treatment of patients to the level of 140 mm Hg or those with baseline SBP of 140 to 159 mm Hg is less strong; thus, these treatment decisions should be more sensitive to patient preferences and tolerance of therapy.   相似文献   
67.
We studied surface expression of granulocyte colony-stimulating factor receptor (G-CSFR) on CD34++  progenitor cells of myelodysplastic patients. Late stages of disease showed a higher proportion of high or low G-CSFR expression than early stages. Most of the patients with the low expression had neutropenia. Neutropenia was relatively less present in the normal group, but it reappeared in the high group. All the neutropenic patients in the high group showed response to G-CSF, while response in the normal group was minor. These findings suggest that lowered expression of G-CSFR leads to neutropenia in myelodysplastic patients. This article reviewed the knowledge of the G-CSFR and its role in the disorders of granulopoiesis, including myelodysplastic syndrome (MDS).  相似文献   
68.
Morphological evaluation and correlation of endometrial hyperplasias, leiomyoma and ovarian estrogen producing lesions. 390 specimens of hysterectomy associated or not with ovarectomy were processed by routine technique and sections stained by H&E staining. 316 cases presented different degrees of endometrial hyperplasias associated with leiomyoma. In 117 from 170 cases the ovary presented estrogen secreting lesions (follicular cyst, polycystic ovary, stromal hyperplasia, granulosa cell tumours). The highest frequency of the uterine and ovarian lesions was in the decades 41-50 years, and 31-40 years. Leiomyoma and endometrial hyperplasia, develop in a hormonal context, most frequently characterized by micropolicystic ovaries. The risk is higher in the perimenopausal period. The most frequent type is simple hyperplasia suggesting a rare progression to highest grades and a possible protective role of leiomyoma as target tissue which capture estrogens.  相似文献   
69.
To evaluate if the immunohistochemical assessment of steroid receptors is helpful in distinguishing Atypical Hyperplasia from Well Differentiated Endometrial Carcinoma, the morphological and immunohistochemical features for steroid receptors were studied in 46 cases of atypical hyperplasia alone or associated with other degrees of hyperplasia or adenocarcinoma. The estrogen and progesterone receptors were determined by the avidin-biotin complex technique using monoclonal antibodies on paraffin embedded tissue. The diagnosis of atypical hyperplasia was based on the observation of epithelial atypias and the absence of the stromal invasion. The positive reaction for steroid receptors was moderate, very variable from case to case, heterogeneous and quite similar to that observed in carcinoma. The morphological identification of the stromal invasion is the most reliable criterion in differentiating endometrial carcinoma from atypical hyperplasia. The steroid receptors assessment is not valuable in this purpose but may be useful in cases in which a hormonal therapy is recommended.  相似文献   
70.
Invasive cervical cancer represents a major health problem in Romania. When there is a functioning screening network, the incidence of invasive lesions has a marked reduction, this program being the most successful cancer prevention program of all times. 80% of the actual incidence and mortality from this disease occurs in countries without an organized screening. A good infrastructure of the cytopathologist--practitioner relation must be achieved in order to reach the standard of early detection of the preinvasive cervical lesions.  相似文献   
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