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BACKGROUND: International guidelines indicate that the long-acting bronchodilators play a key role in the treatment of patients with chronic obstructive pulmonary disease (COPD). The aim of this study was to assess the short term efficacy and safety of 50 and 100 microg bid inhaled salmeterol, compared with placebo and orally dose titrated slow-release theophylline in patients with stable COPD. METHODS: Thirteen patients (67+/-7 years, three females) with moderate-to-severe COPD (FEV1<70% predicted and >30% predicted) and with poor reversibility (post-bronchodilator FEV1<12% and <200 ml from pre-bronchodilator values) completed this single centre randomised, double-blind, double-dummy, four-phase cross-over clinical trial. Patients were randomised to treatment after a 2-week oral corticosteroid trial and a theophylline titration phase. Each treatment lasted 2 week with a 2-week washout period. Values at the end of treatments were compared. RESULTS: Inhaled salmeterol at both tested doses was better than placebo in improving lung function (FEV1, FVC, and morning PEF) of stable patients with moderate COPD over a period of 2 weeks. Although slight (about 170 ml, 150 ml, and 120 ml/min on average, for FEV1, FVC, and PEF, respectively) the improvement was significant. The effects seem to improve only slightly with the higher dose. Salmeterol appeared to be more effective than theophylline treatment when compared to placebo, as theophylline improved significantly, but less, the FEV1 (about 80 ml, on average) without affecting any of the other lung function variables. Salmeterol 100 microg was significantly better than theophylline in improving morning PEF. Four patients reported five adverse events while receiving placebo and 2 and 3 patients reported 2 and 3 adverse events, respectively, during salmeterol 50 microg and salmeterol 100 microg phases. None was considered drug related. Five patients experienced 13 adverse events with theophylline treatment, four of which were considered drug related. CONCLUSION: Inhaled salmeterol improves lung function in stable patients with moderate-to-severe and poorly reversible COPD. The magnitude of improvement in FEV1 observed in this study is similar to that found in longer and larger studies on similar populations of patients. In those studies, that improvement was associated with a better quality of life and less symptoms. Theophylline determined a smaller improvement in FEV1 with more unpleasant side effects that both doses of inhaled salmeterol, though there was no significant difference. It is concluded that salmeterol is an effective and well tolerated therapy, potentially preferable to theophylline, at least in the short-term management of stable COPD.  相似文献   
3.
Phenoloxidases (POs) and haemocyanins constitute a family of copper-containing proteins widely distributed among invertebrates. Both of them are able, under appropriate conditions, to convert polyphenols to quinones and induce cytotoxicity through the production of reactive oxygen species, a fundamental event in many immune responses. In ascidians, PO activity has been described and studied in both solitary and colonial species and the enzyme is involved in inflammatory and cytotoxic reactions against foreign cells or molecules, and in the formation of the cytotoxic foci which characterise the nonfusion reaction of botryllids. Expressed genes for two putative POs (CiPO1 and CiPO2) have been recently identified in C. intestinalis. In the present study, we determined the cDNA sequences of two haemocyanin-like proteins from two colonial ascidians: Botryllus schlosseri from the Mediterranean Sea and Polyandrocarpa misakiensis from Japan. Multiple sequence alignments evidenced the similarity between the above sequences and crustacean proPOs whereas the analysis of the three-dimensional structure reveals high similarity with arthropod haemocyanins which share common precursors with arthropod proPOs. Botryllus HLP grouped in the same cluster with Ciona POs, whereas Polyandrocarpa HLP clustered with arthropod haemocyanins; all of them share the full conservation of the six histidines at the two copper-binding sites as well as of other motifs, also found in arthropod haemocyanin subunits, involved in the regulation of enzyme activity. In situ hybridisation indicated that the genes are transcribed inside morula cells, a characteristic haemocyte type in ascidians where PO activity is located, at the beginning of their differentiation. These results represent a first attempt to identify candidate molecules responsible of the PO activity in compound ascidians.  相似文献   
4.
Glutathione peroxidase (GPx) is a widespread protein superfamily found in many organisms throughout all kingdoms of life. Although it was initially thought to use only glutathione as reductant, recent evidence suggests that the majority of GPxs have specificity for thioredoxin. We present a thorough in silico analysis performed on 724 sequences and 12 structures aimed to clarify the evolutionary, structural, and sequence determinants of GPx specificity. Structural variability was found to be limited to only two regions, termed oligomerization loop and functional helix, which modulate both reduced substrate specificity and oligomerization state. We show that mammalian GPx-1, the canonic selenocysteine-based tetrameric glutathione peroxidase, is a recent "invention" during evolution. Contrary to common belief, cysteine-based thioredoxin-specific GPx, which we propose the TGPx, are both more common and more ancient. This raises interesting evolutionary considerations regarding oligomerization and the use of active-site selenocysteine residue. In addition, phylogenetic analysis has revealed the presence of a novel member belonging to the GPx superfamily in Mammalia and Amphibia, for which we propose the name GPx-8, following the present numeric order of the mammalian GPxs.  相似文献   
5.

Background:

This multicentre, randomized study was designed to assess the clinical efficacy, safety and tolerability of three novel 7-day triple therapies containing ranitidine bismuth citrate (RBC) and two antibiotics.

Methods:

We studied patients with non-ulcer dyspepsia and gastritis who were randomly assigned to one of three treatment regimens given for 7 days in a b.d. dosing schedule: RBC 400 mg plus clarithromycin 250 mg and tinidazole 500 mg (RBCCT); RBC 400 mg plus clarithromycin 500 mg and amoxycillin 1 g (RBCCA); RBC 400 mg plus tinidazole 500 mg and amoxycillin 1 g (RBCTA). H. pylori status was determined by CLO-test, histology and 13C-urea breath test. A repeat breath test was performed at least 28 days after completion of therapy to assess eradication.

Results:

One hundred and fifty-seven patients were eligible for intention-to-treat analysis (ITT) and 140 patients completed the study and returned for assessment of eradication. Intention-to-treat cure rates were 78% with RBCCT, 71% with RBCCA and 61% with RBCTA. An all-patients-treated analysis (APT), performed on evaluable patients, demonstrated eradication rates of 85% with RBCCT, 81% with RBCCA and 70% with RBCTA. No statistically significant difference was found between treatment groups. Twenty-four patients experienced side-effects, but in only seven cases was treatment discontinued due to adverse events.

Conclusions:

A 7-day course of RBC, clarithromycin and either tinidazole or amoxycillin provides a good rate of H. pylori eradication. Three novel RBC-based triple therapies proved to be safe and well tolerated, with discontinuations due to side-effects occurring in less than 5% of cases.
  相似文献   
6.
Accurate prediction of the impact of genomic variation on phenotype is a major goal of computational biology and an important contributor to personalized medicine. Computational predictions can lead to a better understanding of the mechanisms underlying genetic diseases, including cancer, but their adoption requires thorough and unbiased assessment. Cystathionine‐beta‐synthase (CBS) is an enzyme that catalyzes the first step of the transsulfuration pathway, from homocysteine to cystathionine, and in which variations are associated with human hyperhomocysteinemia and homocystinuria. We have created a computational challenge under the CAGI framework to evaluate how well different methods can predict the phenotypic effect(s) of CBS single amino acid substitutions using a blinded experimental data set. CAGI participants were asked to predict yeast growth based on the identity of the mutations. The performance of the methods was evaluated using several metrics. The CBS challenge highlighted the difficulty of predicting the phenotype of an ex vivo system in a model organism when classification models were trained on human disease data. We also discuss the variations in difficulty of prediction for known benign and deleterious variants, as well as identify methodological and experimental constraints with lessons to be learned for future challenges.  相似文献   
7.
A 71-year-old man, with a pial micro-arteriovenous malformation (pAVM) draining into the confluence of the vein of Trolard and the vein of Labbé was surgically removed, sparing these cortical veins. 4-months MR and angiographic controls showed a de novo dural arteriovenous fistula (dAVF) draining into the previously spared cortical veins. It was removed using intraoperative motor evoked potentials (MEP). This is the first case of iatrogenic dAVF developing on the same draining vein of a previously treated pAVM. De novo dAVFs are generally iatrogenic. This case suggests that the unresected venous drainage of an AVM might be the substratum for neo-angiogenetic processes; moreover inflammation related to surgery might be the trigger factor for the development of the dAVF.  相似文献   
8.
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   
9.
Sequence alignment remains a fundamental tool in most tasks related to the prediction of protein sequence and structure. A C++ class library was developed to facilitate the rapid implementation of a variety of state-of-the-art pairwise sequence alignment techniques. These range from simple sequence to sequence to the advanced profile to profile alignments with optional secondary structure information. Suboptimal alignments, frequently used to estimate regions of confidence, can also be generated. The object oriented design facilitates rapid implementation, testing and extension of existing functionality. A simple web interface, which can also be useful in bioinformatics education, is also provided. Source code, online documentation and a prototypical web interface are freely accessible to academic users from the URL: http://protein.cribi.unipd.it/align/. A sample case study in the modelling of human Cytochrome P450 is discussed.  相似文献   
10.
Chronic respiratory diseases affect a large number of subjects in Italy and are characterized by high socio-health costs. The aim of the Social Impact of Respiratory Integrated Outcomes (SIRIO) study was to measure the health resources consumption and costs generated in 1 year by a population of patients with chronic obstructive pulmonary disease (COPD) in a real-life setting. This bottom-up, observational, prospective, multicentric study was based on the collection of demographic, clinical, diagnostic, therapeutic and outcome data from COPD patients who reported spontaneously to pneumological centers participating in the study, the corresponding economic outcomes being assessed at baseline and after a 1-year survey. A total of 748 COPD patients were enrolled, of whom 561 [408 m, mean age 70.3 years (SD 9.2)] were defined as eligible by the Steering Committee. At the baseline visit, the severity of COPD (graded according to GOLD 2001 guidelines) was 24.2% mild COPD, 53.7% moderate and 16.8% severe. In the 12 months prior to enrollment, 63.8% visited a general practitioner (GP); 76.8% also consulted a national health service (NHS) specialist; 22.3% utilized Emergency Care and 33% were admitted to hospital, with a total of 5703 work days lost. At the end of the 1-year survey, the severity of COPD changed as follows: 27.5% mild COPD, 47.4% moderate and 19.4% severe. Requirement of health services dropped significantly: 57.4% visited the GP; 58.3% consulted an NHS specialist; 12.5% used Emergency Care and 18.4% were hospitalized. Compared to baseline, the mean total cost per patient decreased by 21.7% (p<0.002). In conclusion, a significant reduction in the use of health resources and thus of COPD-related costs (both direct and indirect costs) was observed during the study, likely due to a more appropriate care and management of COPD patients.  相似文献   
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