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31.
The insulin-like and vasodilatatory polypeptide relaxin (RLX), formerly known as a pregnancy hormone, has gained interest as a potential humoral mediator in human heart failure. Controversy exists about the relation between plasma levels of RLX and the severity of heart failure. The present study was designed to determine the course of RLX, atrial, and brain natriuretic peptide (NT-proANP and NT-proBNP) during physical exercise in patients with ischemic heart disease (IHD) and to relate hormone levels to peak cardiac power output (CPO) as a measure of cardiopulmonary function with prognostic relevance. 40 patients with IHD were studied during right-heart-catheterization at rest and during supine bicycle ergometry. RLX, NTproBNP, and NTproANP were determined before, during exercise, and after recovery. NT-proANP and NT-proBNP levels increased during maximal charge, and recovery while RLX levels decreased. Cardiac power output at maximal charge correlated inversely with NTproANP and NTproBNP but positively with RLX. Patients with high degree heart failure (CPO < 1.96 W) had higher NTproANP and NTproB-NP and lower RLX levels than patients with low degree heart failure. While confirming the role of NTproANP and NTproBNP as markers for the severity of heart failure, the present data do not support the concept that plasma levels of RLX are related to the severity of myocardial dysfunction and that systemic RLX acts as a compensatory vasodilatatory response hormone in ischemic heart disease.  相似文献   
32.
Summary: IgA nephropathy, or Berger's disease (IgAN), is a worldwide disease which is characterized by a slowly progressive loss of renal function accompanied by decreasing kidney size with the development of glomerulosclerosis and interstitial fibrosis. Immunologic and non-immunologic factors are implicated in the progression of renal damage, since they are potent inducers in stimulating glomerular, tubular and interstitial cells and non-resident cells to produce free oxygen radicals, cytokines, growth factors, chemokines, etc. Recent data from our laboratory and other groups, synthesized in this review, have demonstrated the remarkable involvement of these humoral factors in the progression of renal damage in IgAN patients. Therefore, prospective therapeutic approaches have been suggested in blocking the inflammatory mediators during the pathophysiologic sequelae of immune and non-immune mechanisms which may intervene in the outcome of the disease.  相似文献   
33.
Objective: To establish two stably KGF-transfected, immortalized cell lines. Methods: HaCaT-keratinocytes and KMST-6-fibroblasts were transfected by liposome mediated gene transfer. Transfection effectivity, gene integration and configuration of the transgenic protein were investigated by ELISA, DANN-PCR and β-Gal-staining. Results: Most effective GF producing clones were tested by a colorimetric XTT-test. Conclusion: This is a significant acceleration of cell proliferation and mitosis of human keratinocytes in an Air Liquid Interface (ALI) test system.  相似文献   
34.
Background: One-week triple regimens are currently the most recommended therapy for the eradication of Helicobacter pylori. No previous study has evaluated the efficacy of a short-term regimen combining ranitidine bismuth citrate with two antibiotics. Methods: Seventy-two consecutive H. pylori-positive dyspeptic patients were recruited for this randomized, three-centre, open, parallel-group study. They were subdivided into two groups receiving either ranitidine bismuth citrate 400 mg b.d. + clarithromycin 250 mg b.d. and metronidazole 500 mg b.d. (group A) or ranitidine bismuth citrate 400 mg b.d. + clarithromycin 250 mg b.d. and metronidazole 250 mg q.d.s (group B) for 1 week. H. pylori infection was assessed by CLO-test and histology on both antral and corpus biopsies before and at least 4 weeks after the end of therapy. The bacterium was considered eradicated when both tests were negative. Eradication rates and the number of side-effects were evaluated in each group. The Chi-squared test was used for statistical analysis. Results: One patient with only CLO-test positivity was erroneously randomized to group B and four patients dropped out of the study (two in group A and two in group B), mainly because they refused the second endoscopy. In group A, H. pylori was eradicated in 31 of 36 patients intention-to-treat = 86%; 95% CI = 71–95% and (per protocol 31/34 = 91%; 95% CI = 76–98%). Side-effects occurred in 10 patients (27%) and they were generally mild. In group B, H. pylori was eradicated in 29 of 35 patients (intention-to-treat = 83%; 95% CI = 66–93%; and per protocol 29/33 = 88%; 95% CI = 72–97%). Seven patients (20%) complained of modest side-effects. There was no significant difference between the two treatment arms (P = N.S.); no severe adverse events occurred and none of the patients was withdrawn from the study because of them. Conclusions: The co-administration of ranitidine bismuth citrate plus clarithromycin at low dosage and metronidazole in twice daily doses for 1 week is a short, effective and well-tolerated regimen for the eradication of H. pylori. These findings should provide the impetus for large-scale investigations.  相似文献   
35.
Long-term Effects of Gastric Pacing to Reduce Feed Intake in Swine   总被引:8,自引:2,他引:6  
Background: The purpose of this study was to show the effect of chronic antral gastric electrical stimulation on the feeding behaviour of swine. Methods: Three groups of swine were investigated; first group control-group, second group - 8 months of electrical antral stimulation (10 Volts; 450 micros; Hertz 100; Mode: Cycling; on time 3.25 s; off time 5.15 s), the third group - 3 months of stimulation with modification of the following parameters - amplitude 8 Volts, hertz 5. All animals were nourished with commercial balanced dry feed ad libitum. Results: Group one demonstrated continued increased weight gain. After 90 days of stimulation, group two noted a net decrease of feed intake from 12% to 16%, followed by a net cyclical weight loss 30 days later (2 weeks of weight gain followed by 1 week of weight loss). The percentage difference between group one and two in increasing weight was-12 to 29% respectively. The feed output of the stimulated group (group two) was 12.8 less compared with control. The net weight loss was of 19 to 29.6 kg compared with control. Finally, group three was used to test a lower stimulation rate, resulting in a shorter rest during feeding and a 7% increase in consumption compared with control. Conclusions: Long-term antral gastric pacing influences the alimentary behaviour of swine. We attempt to extrapolate this influence in humans for possible attendant applications in patients with consumption dysfunction (e.g. bulimia and/or anorexia).  相似文献   
36.
In several families with non-specific X-linked mental retardation (XLMR) linkage analyses have assigned the underlying gene defect to the pericentromeric region of the X chromosome, but none of these genes have been isolated so far. Here, we report on the cloning and characterization of a novel gene, DXS6673E, that maps to Xq13.1, is subject to X-inactivation and is disrupted in the 5' untranslated region by a balanced X;13 translocation in a mentally retarded female. The DXS6673E gene is highly conserved among vertebrates and its expression is most abundant in brain. It encodes a hydrophilic protein of 1358 amino acids (aa) that does not show sequence homology to other known proteins. A segment of this protein consisting of neutral and hydrophobic aa with a proline residue in every second position may represent a transmembrane domain. Almost complete sequence identity was found between the 3' end of the DXS6673E gene and two expressed sequence tags (ESTs) and between the 5' end of the DXS6673E gene and a third EST. Moreover, weaker sequence similarity was observed between coding regions and two other ESTs.   相似文献   
37.
Journal of Neuro-Oncology - Medulloblastoma is the most frequent pediatric malignant brain tumor, and is divided into four main subgroups: WNT, SHH, group 3, and group 4. MYCN amplification is an...  相似文献   
38.
BACKGROUND: Proton pump inhibitors can be effective as maintenance therapy in reducing the relapse rate of reflux oesophagitis at a dose lower than that used for acute healing. PATIENTS AND METHODS: Patients (n=396, 18-88 years old) with healed reflux oesophagitis (grade II or III before healing) were included in this multinational, prospective, parallel-group, randomized double-blind study. They took oral pantoprazole 20 mg (n=203) or 40 mg (n=193), once daily for up to 12 months. Scheduled endoscopies were performed at entry, after 6 and 12 months, or when symptoms of at least moderate intensity were perceived on 3 consecutive days; symptoms were assessed every 3 months. The primary efficacy parameter was the time until endoscopically proven relapse of reflux oesophagitis occurred; the secondary parameters included tolerability, safety and time until symptomatic relapse occurred. RESULTS: Analysis was performed using the 'all-patients-treated' approach. Endoscopic relapse rates in the 20 mg group after 6 and 12 months were 16 and 29%, respectively; in the 40 mg group, they were 7 and 19%, respectively. Symptomatic relapse rates after 6 and 12 months were 14 and 21% in the 20 mg group and 10 and 17% in the 40 mg group, respectively. Pantoprazole 20 mg and 40 mg were well tolerated throughout the study; the type and frequency of adverse events reported were similar for both treatment groups. CONCLUSION: The 20 mg dose was proven to be 'at least equivalent' to the 40 mg dose with respect to endoscopic and symptomatic relapse. The 20 mg once daily dose represents an effective and safe maintenance regimen for the majority of patients with healed reflux oesophagitis.  相似文献   
39.
黑翠碱甲和黑翠碱乙的化学结构   总被引:2,自引:0,他引:2  
浦海燕  王锋鹏 《药学学报》1994,29(9):689-692
从黑水翠雀(Delphinium potaninii W.T.Wang)根中分得2个新的牛扁碱型C19-二萜生物碱(I和II),由光谱分析(1HNMR,13CNMR和MS)和化学方法,确定碱I为黑翠碱甲(potanidineA)、碱II为黑翠碱乙(potanidineB)。  相似文献   
40.
Background: This study was initiated 3 years ago when antral gastric electric stimulation was first used successfully to reduce free feeding in swine. Methods: Three swine weighing 45 kg each were implanted with one subserosal bipolar electrode, positioned in the antrum, close to the pylorus, at the anterior side of the lesser gastric curvature. Results: During 4 h of kethamine anaesthesia we paced the stomach by various patterns of electrical stimulation and obtained both forward and backward peristalsis, as well as gastric paresis. Conclusion: Variations in antral electrical stimulation produce characteristic patterns of forward and reverse peristalsis.  相似文献   
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