全文获取类型
收费全文 | 26946篇 |
免费 | 2168篇 |
国内免费 | 682篇 |
专业分类
耳鼻咽喉 | 191篇 |
儿科学 | 1282篇 |
妇产科学 | 783篇 |
基础医学 | 2120篇 |
口腔科学 | 308篇 |
临床医学 | 2451篇 |
内科学 | 4985篇 |
皮肤病学 | 255篇 |
神经病学 | 987篇 |
特种医学 | 1182篇 |
外国民族医学 | 2篇 |
外科学 | 2692篇 |
综合类 | 2530篇 |
现状与发展 | 2篇 |
预防医学 | 3960篇 |
眼科学 | 224篇 |
药学 | 3670篇 |
7篇 | |
中国医学 | 976篇 |
肿瘤学 | 1189篇 |
出版年
2024年 | 32篇 |
2023年 | 562篇 |
2022年 | 938篇 |
2021年 | 1488篇 |
2020年 | 1326篇 |
2019年 | 1382篇 |
2018年 | 1254篇 |
2017年 | 1020篇 |
2016年 | 914篇 |
2015年 | 936篇 |
2014年 | 1957篇 |
2013年 | 1925篇 |
2012年 | 1531篇 |
2011年 | 1845篇 |
2010年 | 1459篇 |
2009年 | 1479篇 |
2008年 | 1459篇 |
2007年 | 1452篇 |
2006年 | 1093篇 |
2005年 | 969篇 |
2004年 | 782篇 |
2003年 | 580篇 |
2002年 | 452篇 |
2001年 | 411篇 |
2000年 | 321篇 |
1999年 | 271篇 |
1998年 | 207篇 |
1997年 | 203篇 |
1996年 | 181篇 |
1995年 | 159篇 |
1994年 | 137篇 |
1993年 | 115篇 |
1992年 | 98篇 |
1991年 | 117篇 |
1990年 | 98篇 |
1989年 | 73篇 |
1988年 | 67篇 |
1987年 | 48篇 |
1986年 | 54篇 |
1985年 | 69篇 |
1984年 | 60篇 |
1983年 | 53篇 |
1982年 | 48篇 |
1981年 | 38篇 |
1980年 | 30篇 |
1979年 | 33篇 |
1978年 | 24篇 |
1977年 | 10篇 |
1976年 | 12篇 |
1973年 | 12篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
11.
Tobias Hüppe Sascha Kreuer Hinnerk Wulf Dennik Freitag Martin Seidel Tobias Teucke Felix Maurer Andreas Kirschbaum Tilo Koch Frank Langer Thomas Volk Carsten Feldmann 《Acta anaesthesiologica Scandinavica》2023,67(4):455-461
Background
Volatile propofol can be measured in exhaled air and correlates to plasma concentrations with a time delay. However, the effect of single-lung ventilation on exhaled propofol is unclear. Therefore, our goal was to evaluate exhaled propofol concentrations during single-lung compared to double-lung ventilation using double-lumen tubes.Methods
In a first step, we quantified adhesion of volatile propofol to the inner surface of double-lumen tubes during double- and single-lumen ventilation in vitro. In a second step, we enrolled 30 patients scheduled for lung surgery in two study centers. Anesthesia was provided with propofol and remifentanil. We utilized left-sided double-lumen tubes to separately ventilate each lung. Exhaled propofol concentrations were measured at 1-min intervals and plasma for propofol analyses was sampled every 20 min. To eliminate the influence of dosing on volatile propofol concentration, exhalation rate was normalized to plasma concentration.Results
In-vitro ventilation of double-lumen tubes resulted in increasing propofol concentrations at the distal end of the tube over time. In vitro clamping the bronchial lumen led to an even more pronounced increase (Δ AUC +62%) in propofol gas concentration over time. Normalized propofol exhalation during lung surgery was 31% higher during single-lung compared to double-lung ventilation.Conclusion
During single-lung ventilation, propofol concentration in exhaled air, in contrast to our expectations, increased by approximately one third. However, this observation might not be affected by change in perfusion-ventilation during single-lung ventilation but rather arises from reduced propofol absorption on the inner surface area of the double-lumen tube. Thus, it is only possible to utilize exhaled propofol concentration to a limited extent during single-lung ventilation.Registration of Clinical Trial
DRKS-ID DRKS00014788 ( www.drks.de ). 相似文献12.
Charles A. Johnson Jared J. Reid William E. Allen Suvleen K. Singh Josef K. Eichinger Richard J. Friedman 《Seminars in Arthroplasty》2022,32(3):594-599
BackgroundThe purpose of this study is to evaluate the effect of body mass index (BMI) on discharge to a postacute care (PAC) facility following elective total shoulder arthroplasty (TSA).MethodsThe National Surgical Quality Improvement Program database was queried to identify adult patients (>18 years old) who underwent inpatient TSA for primary osteoarthritis between 2005 and 2018. Hemiarthroplasty, revision TSA, trauma indications, and outpatient procedures were excluded. Patient and perioperative data were identified. Univariate analysis and multivariate logistic regression were used to assess the relationship between BMI and discharge to PAC facilities.ResultsA total of 10,198 patients with a primary TSA were identified. The majority (93%) of patients were discharged home vs. 7% to PAC facilities. Patients discharged to PAC had significantly higher mean BMI (P = .006). After controlling for demographic and comorbid factors, BMI was the only modifiable risk factor that was independently associated with an increased risk of discharge to a PAC. For every increase in BMI point, there was an increased risk of discharge to a PAC by 2.9% (odds ratio [OR] 1.029, confidence interval [CI] 1.016-1.041, P < .001). Additional covariates associated with PAC discharge were older age (OR 1.113, CI 1.099-1.127, P < .001), female gender (OR 3.037, CI 2.489-3.705, P < .001), and dependent functional status (OR 8.322, CI 5.544-12.492, P < .001).ConclusionMost patients undergoing TSA were discharged home following surgery. While age, sex, and functional status also affect disposition, elevated BMI is the only modifiable risk factor that independently predicts PAC discharge. Consideration of patient BMI prior to elective TSA may greatly improve discharge planning and management of patient expectations. 相似文献
13.
Malou A.H. Nuijten Thijs M.H. Eijsvogels Valerie M. Monpellier Ignace M.C. Janssen Eric J. Hazebroek Maria T.E. Hopman 《Obesity reviews》2022,23(1):e13370
Postbariatric loss of muscle tissue could negatively affect long-term health due to its role in various bodily processes, such as metabolism and functional capacity. This meta-analysis aimed to unravel time-dependent changes in the magnitude and progress of lean body mass (LBM), fat-free mass (FFM), and skeletal muscle mass (SMM) loss following bariatric surgery. A systematic literature search was conducted in Pubmed, Embase, and Web of Science. Fifty-nine studies assessed LBM (n = 37), FFM (n = 20), or SMM (n = 3) preoperatively and ≥1 time points postsurgery. Random-effects meta-analyses were performed to determine pooled loss per outcome parameter and follow-up time point. At 12-month postsurgery, pooled LBM loss was ?8.13 kg [95%CI ?9.01; ?7.26]. FFM loss and SMM loss were ?8.23 kg [95%CI ?10.74; ?5.73] and ?3.18 kg [95%CI ?5.64; ?0.71], respectively. About 55% of 12-month LBM loss occurred within 3-month postsurgery, followed by a more gradual decrease up to 12 months. Similar patterns were seen for FFM and SMM. In conclusion, >8 kg of LBM and FFM loss was observed within 1-year postsurgery. LBM, FFM, and SMM were predominantly lost within 3-month postsurgery, highlighting that interventions to mitigate such losses should be implemented perioperatively. 相似文献
14.
Suicides by pentobarbital overdose have increased since about 2012, which appear to be influenced by technical information on active euthanasia that has spread over the Internet. We encountered a pentobarbital poisoning case of a patient with amyotrophic lateral sclerosis. A caregiver found the patient unconscious immediately after two visitors left the room. The patient was immediately transferred to the emergency hospital but eventually declared dead. A fatal concentration of pentobarbital was detected in peripheral blood samples collected in the emergency hospital and during autopsy (53.8 μg/mL and 29.4 μg/mL, respectively). Because the ratios of pentobarbital concentrations between the gastric contents and peripheral blood were 35 and 29 in the hospital and autopsy samples, respectively, it is likely that pentobarbital was administered via the gastrostomy tube. The patient had contacted the visitors through social media. Although the patient had requested the doctor perform active euthanasia and expressed a desire to end their life on social media, nobody had noticed the plan to commit suicide. 相似文献
15.
16.
《Vaccine》2022,40(24):3320-3329
BackgroundCurrently, booster dose is needed after 2 doses of non-live COVID-19 vaccine. With limited resources and shortage of COVID-19 vaccines, intradermal(ID) administration might be a potential dose-sparing strategy.ObjectiveTo determine immunologic response and reactogenicity of ID ChAdOx1 nCoV-19 vaccine (AZD1222,Oxford/AstraZeneca) as a booster dose after completion of 2-dose CoronaVac(SV) in healthy adult.MethodsThis is a prospective cohort study of adult aged 18–59 years who received 2-dose SV at 14–35 days apart for more than 2 months. Participants received ID AZD1222 at fractional low dose(1×1010 viral particles,0.1 ml). Antibody responses were evaluated by surrogate virus neutralization test(sVNT) against delta variant and wild type, and anti-spike-receptor-binding-domain immunoglobulin G(anti-S-RBD IgG) at prior, day14, 28, 90, and 180 post booster. Solicited reactogenicity was collected for 7 days post-booster. Primary endpoint was the differences of sVNT against delta strain ≥ 80% inhibition at day14 and 90 compared with the parallel cohort study of 0.5-ml intramuscular(IM) route.ResultsFrom August2021, 100 adults with median age of 46 years(IQR 41–52) participated. Prior to booster, geometric mean(GM) of sVNT against delta strain was 22.4% inhibition(95 %CI 18.7–26.9) and of anti-S-RBD IgG was 109.3 BAU/ml(95.4–125.1). Post ID booster, GMs of sVNT against delta strain were 95.5% inhibition (95%CI 94.2–96.8) at day14, 73.1% inhibition (66.7–80.2) at day90, and 22.7% inhibition (14.9–34.6) at day180. The differences of proportion of participants achieving sVNT against delta strain ≥ 80% inhibition in ID recipients versus IM were + 4.2% (95 %CI -2.0to10.5) at day14, and ?37.3%(-54.2to-20.3) at day90. Anti-S-RBD IgG GMs were 2037.1 BAU/ml (95%CI 1770.9–2343.2) at day14 and 744.6 BAU/ml(650.1–852.9) at day90, respectively. Geometric mean ratios(GMRs) of anti-S-RBD IgG were 0.99(0.83–1.20) at day14, and 0.82(0.66–1.02) at day90. Only 18% reported feverish, compared with 37% of IM (p = 0.003). Common reactogenicity was erythema at injection site(53%) while 7% reported blister.ConclusionLow-dose ID AZD1222 booster enhanced lower neutralizing antibodies at 3 months compared with IM route. Less systemic reactogenicity occurred, but higher local reactogenicity. 相似文献
17.
《Pancreatology》2022,22(2):270-276
Backgroundand purpose: Zinc is an essential element for human health and plays an important role in metabolic, immunological and other biological processes. The present study was conducted to investigate the association between zinc deficiency (ZD) and the perioperative clinical course in patients with pancreatic ductal adenocarcinoma (PDAC).MethodsOf 216 patients with PDAC who underwent elective pancreatectomy between 2013 and 2017 at our institution, 206 patients with sufficient clinical data were retrospectively reviewed. The perioperative variables were compared and the risk factors associated with infectious complications were identified.ResultsZD was preoperatively present in 36 (17.5%) of 206 patients with PDAC. In the patients of the ZD group, a higher proportion of males, higher preoperative modified Glasgow prognostic scores, a higher neutrophil-to-lymphocyte ratio, and a higher occurrence of postoperative infectious complications after pancreatectomy were observed, compared to the non-ZD group. By a univariate analysis, three risk factors were significantly associated with infectious complications after pancreatectomy: ZD (vs non-ZD: p = 0.002), serum albumin <3.5 g/dl (vs ≥ 3.5 g/dl: p = 0.005), and the procedure of pancreaticoduodenectomy (vs others: p = 0.013). By multivariate logistic regression analysis, the occurrence of infectious complications was significantly associated with ZD (OR 3.430, 95%CI 1.570 to 7.490, p = 0.002) and the procedure of pancreaticoduodenectomy (OR 2.030, 95%CI 1.090 to 3.770, p = 0.025).ConclusionsThe current study newly demonstrated that ZD could serve as a preoperative predictor of infectious complications after pancreatectomies in the patients with PDAC. 相似文献
18.
《Clinical breast cancer》2020,20(1):e89-e98
IntroductionA reliable risk stratification on the basis of tumor biology and host factors of HER2-positive (HER2+) early breast cancer (eBC) patients is needed. The aim of our study was to assess the prognostic role of body mass index (BMI) and hormone receptor (HR) expression in this setting.Patients and MethodsWe retrospectively evaluated 238 women with stage I to III HER2+ breast cancer who completed adjuvant chemotherapy (CHT) and 1 year of treatment with trastuzumab. The end point was 3-year distant disease-free survival (3yDDFS). Survival analysis was evaluated using the Kaplan–Meier method. Multivariate analysis was performed using Cox proportional-hazards model adjusting for HR status, BMI, tumor staging, size, nodal status, and type of adjuvant CHT. Association among categorical variables was assessed using χ2 test.ResultsThe early recurrence rate after 3 years resulted as 4.2% (40% HR+ patients and 60% HR− patients). Neither HR status nor BMI alone showed an association with 3yDDFS in multivariate analysis. However, the hazard ratios for patients with HR− tumors who had also BMI ≥25 (3yDDFS 86.9%; 95% confidence interval [CI], 75.0%-97.7%) were amplified compared with patients with HR+ tumors and with BMI <25 (3yDDFS 98%; 95% CI, 94.8%-100.0%) and other subgroups (P = .003). This observation was confirmed in multivariate analysis (hazard ratio, 1.79; 95% CI, 1.04-3.07; P = .03).ConclusionOur real-life data highlight a different risk of eBC recurrence after grouping patients according to HR status and BMI. These results might help clinicians to identify correct treatment strategies. Patients who are HR− and have BMI ≥25 might benefit from escalation approaches, whereas those who are HR+ and have BMI <25 might be eligible for a shorter duration of adjuvant treatment with anti-HER2 agents. 相似文献
19.
Seulbi Lee Hyesook Park Soontae Kim Eun-Kyung Lee Jiyoung Lee Young Sun Hong Eunhee Ha 《International journal of hygiene and environmental health》2019,222(3):533-540
Background
It has been reported that particulate matter (PM) is associated with cardiovascular diseases (CVD) while metabolic syndrome is also an important risk factor for CVD. However, few studies have investigated the epidemiological association between PM and metabolic syndrome.Objective
To investigate the association between one-year exposure to PM with an aerodynamic diameter <2.5?μm (PM2.5) and the risk of metabolic syndrome in Korean adults without CVD.Methods
Exposure to PM2.5 was assessed using a Community Multiscale Air Quality (CMAQ) model. Metabolic syndrome was defined by National Cholesterol Education Program Adult Treatment Panel III. Andersen and Gill model with time-varying covariates, considering recurrent events, was used to investigate the association between one-year average PM2.5 and the risk of incident metabolic syndrome in 119,998 adults from the national health screening cohort provided by Korea National Health Insurance from 2009 to 2013.Results
Higher risk of metabolic syndrome, waist-based obesity, hypertension, hypertriglyceridemia, low HDL cholesterol, and hyperglycemia were significantly associated with a 10-μg/m3 increase in PM2.5 [adjusted hazard ratio (HR): 1.070, 1.510, 1.499, 1.468, 1.627 and 1.380, respectively]. In addition, the risk of metabolic syndrome associated with PM2.5 exposure was significant in the consistently obese group (obese at baseline and endpoint).Conclusion
Exposure to one-year average PM2.5 is associated with an increased risk of metabolic syndrome and its components in adults without CVD. These associations are particularly prominent in the consistently obese group (obese at baseline and endpoint). Our findings indicate that PM2.5 affects the onset of MS and its components which may lead to increase the risk of CVD. 相似文献20.
Joshua Demb Esther K. Wei Monika Izano Stephen Kritchevsky Helen Swede Anne B. Newman Michael Shlipak Tomi Akinyemiju Steven Gregorich Dejana Braithwaite 《Journal of Geriatric Oncology》2019,10(2):265-271