全文获取类型
收费全文 | 500篇 |
免费 | 42篇 |
专业分类
耳鼻咽喉 | 1篇 |
儿科学 | 34篇 |
妇产科学 | 6篇 |
基础医学 | 55篇 |
口腔科学 | 9篇 |
临床医学 | 62篇 |
内科学 | 128篇 |
皮肤病学 | 24篇 |
神经病学 | 15篇 |
特种医学 | 38篇 |
外科学 | 73篇 |
综合类 | 15篇 |
预防医学 | 33篇 |
眼科学 | 4篇 |
药学 | 23篇 |
1篇 | |
中国医学 | 1篇 |
肿瘤学 | 20篇 |
出版年
2023年 | 4篇 |
2022年 | 3篇 |
2021年 | 11篇 |
2020年 | 6篇 |
2019年 | 6篇 |
2018年 | 14篇 |
2017年 | 5篇 |
2016年 | 13篇 |
2015年 | 16篇 |
2014年 | 11篇 |
2013年 | 20篇 |
2012年 | 16篇 |
2011年 | 20篇 |
2010年 | 19篇 |
2009年 | 17篇 |
2008年 | 17篇 |
2007年 | 24篇 |
2006年 | 13篇 |
2005年 | 18篇 |
2004年 | 20篇 |
2003年 | 12篇 |
2002年 | 9篇 |
2001年 | 13篇 |
2000年 | 14篇 |
1999年 | 10篇 |
1998年 | 12篇 |
1997年 | 25篇 |
1996年 | 14篇 |
1995年 | 9篇 |
1994年 | 11篇 |
1993年 | 8篇 |
1992年 | 7篇 |
1991年 | 5篇 |
1990年 | 10篇 |
1989年 | 11篇 |
1988年 | 14篇 |
1987年 | 9篇 |
1985年 | 10篇 |
1984年 | 7篇 |
1983年 | 6篇 |
1982年 | 5篇 |
1981年 | 6篇 |
1977年 | 11篇 |
1976年 | 5篇 |
1973年 | 2篇 |
1972年 | 3篇 |
1971年 | 3篇 |
1970年 | 2篇 |
1968年 | 2篇 |
1964年 | 2篇 |
排序方式: 共有542条查询结果,搜索用时 31 毫秒
1.
Iolter Cattabriga Davide Pacini Gaia Lamazza Francesco Talarico Roberto Di Bartolomeo Giovanni Grillone Letizia Bacchi-Reggiani 《European journal of cardio-thoracic surgery》2007,32(3):527-531
BACKGROUND: Nonsteroidal anti-inflammatory drugs and opioids are routinely used after cardiac surgery in order to mitigate postoperative pain; however, these drugs are burdened by side effects. Tramadol and paracetamol are believed to be lacking in such side effects. The aim of this study was to examine the efficacy of intravenous paracetamol as an adjunctive analgesic to a tramadol-based background analgesia after cardiac surgery. METHODS: A total of 113 patients participated in this single center, placebo-controlled, double-blind, randomized trial. Fifty-six patients were randomized to receive paracetamol and 57 to placebo. Intravenous study drug (1 g) was administered 15 min before the end of surgery and every 6h for 72 h. Standard analgesia (tramadol) and anti-emetic prophylactic regimen (ondansetron) were available to both patient groups. Postoperative pain was evaluated by visual analog scale, and it was measured at rest and during a deep breath. A rescue dose of 2-5 mg of intravenous morphine was administered whenever the VAS score was greater than 3. RESULTS: Baseline characteristics were equivalent between the two groups. At 12, 18, 24 h after the end of operation, patients who received paracetamol had significantly less pain at rest (p=0.0041, 0.0039, 0.0044, respectively); after this time the two groups did not differ. During a deep breath the difference was significant only at 12 h (p=0.0040). Paracetamol group required less cumulative morphine than placebo group (48 mg vs 97 mg) even if the difference did not reach statistical significance (p=0.274). CONCLUSIONS: In patients undergoing cardiac surgery, intravenous paracetamol in combination with tramadol provides effective pain control. 相似文献
2.
G Bajardi G Ricevuto G Mastrandrea F Talarico G Giuntini M Leopizzi G Pischedda 《Minerva chirurgica》1990,45(7):477-480
In this paper the Authors discuss about femoral anastomotic pseudoaneurysms. They throughly consider the etiopathogenesis of this late complication of arterial prothesic surgery, pointing out the different hypothesis currently discussed. Particularly from this analysis it can be concluded that the choice of appropriate prothesic grafts and the weakness of an eventually endarterectomized arterial wall are the principal determinants in causing pseudoaneurysms. Between the different therapeutic choices the opportunity of an interposition graft is underlined, except for (rare) cases when an extra-anatomic bypass must be preferred. 相似文献
3.
Aim of the study was to verify the reliability of thoracic bioimpedance cardiography (TEB) in detection, non-invasively, cardiac index (IC) and ejection fraction (FE), compared to simultaneous evaluation by invasive thermodilution (TD) in 39 patients with acute myocardial infarction in Killip class I-II (group I), and by cineventriculography (CVG) in 26 patients with chronic coronary artery disease in NYHA class I-II (group II). In order to define the reproducibility of TEB values, in the latter patients, the above mentioned parameters were evaluated 6 times more, running the first evaluation. The statistical analysis was performed by the linear regression test and the Student's "t" test and by the test of variance for the reproducibility evaluation. Results (mean +/- SD) were as follows: group I: TEB-IC 2.89 +/- 0.63; TD-IC 2.83 +/- 0.56 (1/min/m2); r = 0.68; p < 0.01. Group II: TEB-IC 2.88 +/- 0.71; CVG-IC 3.48 +/- 0.66; r = 0.77; p < 0.001; TEB-FE 57.7 +/- 6.8%; CVG-FE 58.1 +/- 13.7%; r = 0.40; p = ns. Results of the reproducibility referred to the 6 measurements (mean +/- SD) were the follows: TEB-IC (1/min/m2) (1) 2.83 +/- 0.76; (2) 2.85 +/- 0.73; (3) 2.8 +/- 0.79; (4) 2.83 +/- 0.71; (5) 2.87 +/- 0.81; (6) 2.88 +/- 0.8, p = ns, the variability was assesses within +/- 9.3%. TEB-FE (%): (1) 56.7 +/- 6.2; (2) 55.8 +/- 5; (3) 57.1 +/- 5.5; (4) 56.1 +/- 6.1; (5) 55.4 +/- 5.8; (6) 57.3 +/- 6.3, p = ns; the variability was assessed within +/- 9.1%. The analysis of the results showed a good correlation in the IC detection among TEB and the compared techniques, conversely TEB evaluation of FE appear of poor values in this kind of patients. Relatively to the results of the reproducibility this unquestionable characteristic of TEB was demonstrated. 相似文献
4.
Talarico S Cave MD Marrs CF Foxman B Zhang L Yang Z 《Journal of clinical microbiology》2005,43(10):4954-4960
PE_PGRS33, one of about 60 PE_PGRS genes in the Mycobacterium tuberculosis genome, encodes a surface-expressed protein that may be involved in the antigenic variation of M. tuberculosis strains and evasion of the host immune system. While genetic differences between the PE_PGRS33 genes of H37Rv and CDC1551 have been noted, genetic variation in this gene among clinical isolates has not been evaluated. In order to gain a better understanding of the genetic basis for the role of PE_PGRS in antigenic variation and evasion of the host immune system, we investigated the genetic diversity of the PE_PGRS33 gene among 123 clinical M. tuberculosis isolates from a population-based study, using PCR and DNA sequencing. The 123 isolates belonged to principal genetic groups 1, 2, and 3 and had IS6110 copy numbers ranging from 1 to 22. Eighty-four (68.3%) of the 123 isolates were found to have at least one sequence variation in the PE_PGRS33 gene, relative to that of H37Rv. Twenty-five different sequence variations were observed and included three insertions (ranging from 9 to 87 bp), nine deletions (ranging from 1 to 273 bp), one insertion-and-deletion event, and 12 single-nucleotide polymorphisms (six synonymous and six nonsynonymous). Analysis of the relationships among the different PE_PGRS33 gene sequence variations suggests that polymorphisms in the gene are shifting along evolutionary lineages. The observed genetic diversity of the PE_PGRS33 gene supports its role in antigenic variation and can serve as a basis for future investigations of the function of the PE_PGRS33 gene among clinical isolates. 相似文献
5.
Different modulation by histamine of IL-4 and interferon-gamma (IFN-γ) release according to the phenotype of human Th0, Th1 and Th2 clones
下载免费PDF全文
![点击此处可从《Clinical and experimental immunology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Histamine, an important inflammatory mediator in allergic diseases and asthma, has been reported to have modulator effects on T cells, suggesting that the bronchial microenvironment may regulate the function of resident T cells. We examined the effect of histamine on the release of the Th2-associated cytokines IL-4 and IL-5 and the Th1-associated cytokine IFN-γ by 30 CD4+ T cell clones from peripheral blood or bronchial biopsy of one atopic subject. Based on the IL-4/IFN-γ ratio, the clones were ascribed to the Th2 (ratio >1), Th0 (ratio 0.1 and 1) or Th1 (ratio <0.1) phenotype. Histamine inhibited IFN-γ production by Th1-like cells (P<0.02, Kruskall–Wallis), especially from bronchial biopsy, but had no effect on IL-4 release. Regarding Th0 clones, histamine inhibited IL-4 production (P<0.02) in a dose-dependent manner and slightly inhibited IFN-γ production, but had no effect on Th2-like cells. Histamine had a heterogeneous and insignificant effect on IL-5 production. The H2-receptor antagonist ranitidine completely reversed the inhibition of IL-4 and IFN-γ production, whereas the agonist dimaprit mimicked this effect. In contrast, H1- and H3-receptor agonists and antagonists had no significant effect. These data demonstrate that histamine has different effects on IL-4 and IFN-γ release by T helper cells according to their phenotype via H2-receptors. This study extends the immunomodulatory effects of histamine which may contribute to the perpetuation of airway inflammation in asthma. 相似文献
6.
The role of size, sequence and haplotype in the stability of FRAXA and FRAXE alleles during transmission 总被引:2,自引:5,他引:2
Murray A; Macpherson JN; Pound MC; Sharrock A; Youings SA; Dennis NR; McKechnie N; Linehan P; Morton NE; Jacobs PA 《Human molecular genetics》1997,6(2):173-184
Factors involved in the stability of trinucleotide repeats during
transmission were studied in 139 families in which a full mutation,
premutation or intermediate allele at either FRAXA or FRAXE was
segregating. The transmission of alleles at FRAXA, FRAXE and four
microsatellite loci were recorded for all individuals. Instability within
the minimal and common ranges (0-40 repeats for FRAXA, 0-30 repeats for
FRAXE) was extremely rare; only one example was observed, an increased in
size at FRAXA from 29 to 39 repeats. Four FRAXA and three FRAXE alleles in
the intermediate range (41-60) repeats for FRAXA, 31-60 for FRAXE) were
unstably transmitted. Instability was more frequent for FRAXA intermediate
alleles that had a tract of pure CGG greater than 37 although instability
only occurred in two of 13 such transmissions: the changes observed were
limited to only one or two repeats. Premutation FRAXA alleles over 100
repeats expanded to a full mutation during female transmission in 100% of
cases, in agreement with other published series. There was no clear
correlation between haplotype and probability of expansion of FRAXA
premutations. Instability at FRAXA or FRAXE was more often observed in
conjunction with a second instability at an independent locus suggesting
genomic instability as a possible mechanism by which at least some FRAXA
and FRAXE mutations arise.
相似文献
7.
Elizabeth Kunkel Peter Tanuseputro Amy Hsu Robert Talarico Julie Lapenskie Samantha Calder-Sprackman Daniel Kobewka 《Journal of the American Medical Directors Association》2021,22(4):901-906.e4
ObjectivesTo investigate the association between rapid access to radiographs, blood tests, urine cultures, and intravenous (IV) therapy in a long-term care (LTC) home with resident transfers to the emergency department (ED).DesignRetrospective cohort study.Setting and Participants21,811 residents living in 162 LTC homes in Ontario, Canada.MethodsWe administered a survey to LTC homes to collect wait times for radiographs, basic blood tests, urine culture, and IV therapy. Rapid availability was defined as typically receiving test results within 1 or 2 days, or same-day IV therapy. We linked the survey results to administrative data and defined a cohort of residents living in survey-respondent homes between January and May 2017. We followed residents in the linked administrative databases for 6 months, until discharge, or death. Two physicians identified diagnostic codes for ED visits that were potentially preventable with rapid availability of each of the 4 resources. Multilevel logistic regression models estimated associations between potentially preventable ED visits and rapid diagnostic tests and intravenous access while controlling for demographic characteristics, illness severity, LTC home size, chain status, and physician availability.ResultsRapid blood tests, radiographs, urine culture, and IV therapy were available in 55%, 47%, 34%, and 45% of LTC homes, respectively. LTC homes that were part of multihome chains were less likely to have rapid access to the 4 resources. Of the 4736 residents (27%) who visited an ED during follow-up, individuals from homes with rapid access to radiographs (odds ratio 0.79, 95% confidence interval 0.66-0.97), urine culture (0.88, 0.72-1.08), blood tests (0.83, 0.69-1.00), and IV therapy (0.93, 0.70-1.23) tended to have fewer potentially preventable ED visits.Conclusions and ImplicationsRapid access to diagnostic testing and IV therapy in LTC reduced ED visits. Improving access to these resources may prevent ED visits and allow residents to stay home. 相似文献
8.
JM Langley JC LeBlanc EE Wang BJ Law NE MacDonald I Mitchell D Stephens J McDonald FD Boucher S Dobson 《Pediatrics》1997,100(6):943-946
OBJECTIVE: To determine nosocomial transmission of respiratory syncytial virus (RSV) in Canadian pediatric hospitals, outcomes associated with nosocomial disease, and infection control practices. DESIGN: A prospective cohort study in the 1992 to 1994 winter respiratory seasons. SETTING: Nine Canadian pediatric university-affiliated hospitals. PARTICIPANTS: Hospitalized children with symptoms of lower respiratory tract infection (at least one of cough, wheezing, dyspnea, tachypnea, and apnea) and RSV antigen identified in a nasopharyngeal aspirate. RESULTS: Of 1516 children, 91 (6%) had nosocomial RSV (NRSV), defined as symptoms of lower respiratory tract infection and RSV antigen beginning >72 hours after admission. The nosocomial ratio (NRSV/[com-munity-acquired RSV {CARSV})] + NRSV) varied by site from 2.8% to 13%. The median length of stay attributable to RSV for community-acquired illness was 5 days, but 10 days for nosocomial illness. Four children with NRSV (4. 4%) died within 2 weeks of infection, compared with 6 (0.42%) with CARSV (relative risk = 10.4, 95% confidence interval: 3.0, 36.4). All sites isolated RSV-positive patients in single rooms or cohorted them. In a multivariate model, no particular isolation policy was associated with decreased nosocomial ratio, but gowning to enter the room was associated with increased risk of RSV transmission (incidence rate ratio 2.81; confidence interval: 1.65, 4.77). CONCLUSIONS: RSV transmission risk in Canadian pediatric hospitals is generally low. Although use of barrier methods varies, all sites cohort or isolate RSV-positive patients in single rooms. Children with risk factors for severe disease who acquire infection nosocomially have prolonged stays and excess mortality. 相似文献
9.
A 17-year-old girl was found vomiting and somnolent at home and was taken to a hospital. The girl initially presented with ventricular tachycardia with broad QRS complexes which was very difficult to control. During the course a subsequent cardiogenic shock developed and despite exhaustion of all therapeutic options the fatal outcome could not be averted. The medicolegal autopsy revealed no evidence of any form of violence but the signs of medical treatment. Furthermore, no pathology of internal organs was detected. The toxicological analyses revealed a lethal intoxication with flecainide as the cause of death. The investigations of the police indicated that the girl took flecainide in suicidal intention. 相似文献
10.