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61.
62.
Excluding studies from Brechot and co-workers, little supporthas been found for a role of the hepatitis B virus in the pathogenesisof HBsAg seronegative patients with predominantly chronic liverdiseases, including primary liver cancer. In this study liverDNA from 59 predominantly British patients (four cases withpaired biopsies, 6–12 months apart) with different, mostlychronic, liver diseases was analysed by molecular hybridization.All were seronegative for HBsAg and serum hepatitis B virusDNA (dot blot hybridization) and their liver diseases were believedto be unrelated to hepatitis B virus infection. Hepatitis Bvirus DNA was detected in liver of 11 (18.6 per cent) patients;nine had episomal(3.2 Kb) DNA and eight had higher molecularweight bands suggesting integrated forms. Six patients werealso seronegative for anti-HBc. Patients of UK and non-UK originwere equally represented. Hepatitis B virus DNA was detectedin serum of six of nine patients tested using the polymerasechain reaction. The detection of hepatitis B virus DNA in liverand in serum by this assay in a significant proportion of patientswith chronic liver disease, hitherto unsuspected of being hepatitisB virus-related, suggests a possible role for this virus inlow- as well as high-prevalence countries.  相似文献   
63.
目的:总结低氧训练对下丘脑-垂体-肾上腺皮质轴内分泌相关激素的影响,为科学运动训练提供依据。资料来源:应用计算机检索中国期刊全文数据库1994-01/2006-10的相关文章,检索词"低氧,低氧训练,下丘脑-垂体-肾上腺,激素",并限定文章语言种类为中文。并应用计算机检索美国国立医学图书馆NCBI1980-01/2006-10的相关文章,检索词"Hypoxic Training,organism endocrine system,hormone",并限定文章语言种类为English。资料选择:对资料进行初审,选取低氧训练与下丘脑-垂体-肾上腺分泌的相关激素有关的文献,并作初步分类,同类文献首选近年发表的核心期刊文章。排除重复及综述类文献。资料提炼:共收集到95篇相关文章,其中56篇属于重复及综述类文献,对符合标准38篇文献进行分析整理。资料综合:①高海拔状态下机体对低氧产生应激反应,表现为下丘脑-垂体-肾上腺皮质轴的适应性运转,血中促肾上腺皮质激素浓度增加,以调节机体对应激刺激的适应能力,同时使促肾上腺皮质激素释放因子分泌增加。②高原训练后,睾酮和皮质醇的变化都较明显,其总体变化均趋于降低,睾酮/皮质醇值有升有降,从一定意义上反映了机体的机能状况与疲劳积累程度。③低氧还引起大鼠血浆β-内啡肽浓度升高,可使心房钠尿素增加、前列腺素增加、血管内皮素分泌增加及抑制血管内皮舒张因子的分泌。结论:激素对机体的新陈代谢、生长发育、各种功能活动以及维持内环境稳态等方面发挥重要的调节作用,低氧训练对机体激素的影响一直应该受到人们的关注。  相似文献   
64.
1. In the present investigation with rings of everted rat small intestine, carbohydrate gelling agents (plant polysaccharides) such as guaran, pectin, tragacanth, carubin and carrageenan were employed to study their direct effect on intestinal absorption of alpha-methyl-D-glucoside, D-galactose, L-leucine and L-phenylalanine. 2. Inhibition was found to correlate with the viscosity of the incubation medium, a function only of the polysaccharide concentration, and was independent of other properties of the carbohydrate gelling agents. 3. Reversal of this inhibition was achieved either by washing the tissue free of polysaccharide or by raising tissue agitation. 4. Uptake kinetics in polysaccharide-containing solutions revealed a marked increase of the apparent Michaelis constant although the maximal transport capacity remained essentially unaltered. 5. Since there was no binding of the substrate by the polysaccharides under experimental conditions as judged by a membrane filtration technique, it is concluded that carbohydrate gelling agents may impair intestinal absorption by means of an increased unstirred layer resistance.  相似文献   
65.
AIM: To correlate the significance of liver biochemical tests in diagnosing post orthotopic liver transplantation (OLT) biliary complications and to study their profile before and after endoscopic therapy. METHODS: Patients who developed biliary complications were analysed in detail for the clinical information,laboratory tests,treatment offered,response to it,follow up and outcomes. The profile of liver enzymes was determined. The safety,efficacy and outcomes of endoscopic retrograde cholangiography (ERC) were also analysed. RESULTS: 40 patients required ERC for 70 biliary complications. GGT was found to be > 3 times (388.1 ± 70.9 U/mL vs 168.5 ± 34.2 U/L,P = 0.007) and SAP > 2 times (345.1 ± 59.1 U/L vs 152.7 ± 21.4 U/L,P = 0.003) the immediate post OLT values. Most frequent complication was isolated anastomotic strictures in 28 (40%). Sustained success was achieved in 26 (81%) patients. CONCLUSION: Biliary complications still remain an important problem post OLT. SAP and GGT can be used as early,non-invasive markers for diagnosis and also to assess the adequacy of therapy. Endoscopic management is usually effective in treating the majority of these biliary complications.  相似文献   
66.
BACKGROUND AND GOALS: To develop and validate a disease-specific instrument for measuring health-related quality of life (HRQOL) in patients with adult celiac disease (CD). STUDY: Based on a Medline search of the literature, responses from 10 CD patients and 4 medical experts items potentially affecting HRQOL in CD were identified. This pool was reduced and pretested by 10 other patients and 4 medical experts constructing a preliminary version of the Celiac Disease Questionnaire (CDQ). In a national survey involving 522 respondents of 1000 CD patients (median age 45 y; 78% female) posted by the German Celiac Society completed a medical and sociodemographic questionnaire, the CDQ, the Short Form Health Survey (SF-36), the Hospital Anxiety and Depression Scale German Version HADS-D and the Giessener Symptom List (GBB 24). Subscales were constructed by a principal factor analysis following predefined criteria and validated with other HRQOL measures. Forty-seven out of one hundred patients answered the CDQ a second time 4 weeks after the first posting for the assessment of test-retest reliability. RESULTS: The factor analysis suggested 4 domains with 7 items each: emotional and social problems, disease-related worries, and gastrointestinal symptoms. The Cronbach alpha for the subscales ranged from 0.80 to 0.91. Test-retest reliability correlations ranged from 0.45 to 0.89. The correlation coefficients with comparable subscales of other instruments ranged between 0.26 and 0.79. The CDQ discriminated in all subscales patients with CD-associated diseases from patients without CD-associated diseases (P<0.001). CONCLUSIONS: The CDQ is an instrument suited for future use in clinical and research settings.  相似文献   
67.
BACKGROUND: Antacids are widely used in the self-treatment of gastroesophageal reflux-induced complaints, but respective studies are lacking. GOALS: To compare the efficacy and safety of hydrotalcite with the H2 receptor antagonist famotidine and placebo in the on-demand treatment of acute heartburn under daily practice conditions. STUDY: Five hundred sixty-two individuals in 4 centers were randomized in a double-blind, double-dummy, 3-fold cross-over study to single-dose treatments of 1000 mg hydrotalcite, 10 mg famotidine, or placebo. Heartburn severity and relief was measured with numerical and visual rating scales. RESULTS: A significantly better heartburn relief score was achieved 60 minutes after administration of hydrotalcite compared with placebo (primary end point, P<0.0001). Better efficacy was also observed 30 minutes and 3 hours after the intake of hydrotalcite in comparison with famotidine or placebo. A significant decrease in heartburn severity compared with placebo occurred within 10 minutes for hydrotalcite and was faster compared with both controls. CONCLUSIONS: For subjects self-administering antacids for episodic heartburn, antacid hydrotalcite provides symptom relief significantly faster and, within the first 3 hours postdosing, more effective than famotidine or placebo. These results suggest that on-demand treatment of hydrotalcite is an effective and well-tolerated therapy for heartburn.  相似文献   
68.
The therapeutic potential for manipulation of glucocorticoid metabolism in cardiovascular disease was revolutionized by the recognition that access of glucocorticoids to their receptors is regulated in a tissue-specific manner by the isozymes of 11β-hydroxysteroid dehydrogenase. Selective inhibitors of 11β-hydroxysteroid dehydrogenase type 1 have been shown recently to ameliorate cardiovascular risk factors and inhibit the development of atherosclerosis. This article addresses the possibility that inhibition of 11β-hydroxsteroid dehydrogenase type 1 activity in cells of the cardiovascular system contributes to this beneficial action. The link between glucocorticoids and cardiovascular disease is complex as glucocorticoid excess is linked with increased cardiovascular events but glucocorticoid administration can reduce atherogenesis and restenosis in animal models. There is considerable evidence that glucocorticoids can interact directly with cells of the cardiovascular system to alter their function and structure and the inflammatory response to injury. These actions may be regulated by glucocorticoid and/or mineralocorticoid receptors but are also dependent on the 11β-hydroxysteroid dehydrogenases which may be expressed in cardiac, vascular (endothelial, smooth muscle) and inflammatory (macrophages, neutrophils) cells. The activity of 11β-hydroxysteroid dehydrogenases in these cells is dependent upon differentiation state, the action of pro-inflammaotory cytokines and the influence of endogenous inhibitors (oxysterols, bile acids). Further investigations are required to clarify the link between glucocorticoid excess and cardiovascular events and to determine the mechanism through which glucocorticoid treatment inhibits atherosclerosis/restenosis. This will provide greater insights into the potential benefit of selective 11β-hydroxysteroid dehydrogenase inhibitors in treatment of cardiovascular disease.  相似文献   
69.
Large vessel vasculitis is characterized by local inflammation of the vessel wall of the aorta and its first and second degree branches. Giant cells are found regularly. The process leads to stenoses and occlusions as well as to aneurysmatic dilatation. Recent progress in vascular imaging (colour Doppler ultrasound, MRI and PET) allows to detect Takayasu arteritis at an earlier stage and to reveal the involvement of larger arteries in temporal arteritis (giant cell arteritis, GCA). With increasing frequency, a subtype of predominantly female and less aged GCA patients without cranial symptoms is noticed in whom obstructions are prevailing in the proximal arm vessels or in the aorta. The latter may be affected exclusively. Initial therapy is based on corticosteroids. In GCA, methotrexate hitherto is the only other immunosuppressive drug that has proved to be helpful. Disease activity has to be controlled both by laboratory parameters and vascular imaging.  相似文献   
70.
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