全文获取类型
收费全文 | 12124篇 |
免费 | 882篇 |
国内免费 | 140篇 |
专业分类
耳鼻咽喉 | 96篇 |
儿科学 | 301篇 |
妇产科学 | 257篇 |
基础医学 | 2201篇 |
口腔科学 | 162篇 |
临床医学 | 1318篇 |
内科学 | 2596篇 |
皮肤病学 | 250篇 |
神经病学 | 760篇 |
特种医学 | 731篇 |
外国民族医学 | 1篇 |
外科学 | 1562篇 |
综合类 | 128篇 |
一般理论 | 2篇 |
预防医学 | 754篇 |
眼科学 | 143篇 |
药学 | 1108篇 |
中国医学 | 12篇 |
肿瘤学 | 764篇 |
出版年
2023年 | 76篇 |
2021年 | 172篇 |
2020年 | 157篇 |
2019年 | 209篇 |
2018年 | 262篇 |
2017年 | 218篇 |
2016年 | 230篇 |
2015年 | 261篇 |
2014年 | 323篇 |
2013年 | 457篇 |
2012年 | 568篇 |
2011年 | 529篇 |
2010年 | 327篇 |
2009年 | 340篇 |
2008年 | 475篇 |
2007年 | 525篇 |
2006年 | 457篇 |
2005年 | 448篇 |
2004年 | 395篇 |
2003年 | 343篇 |
2002年 | 322篇 |
2001年 | 328篇 |
2000年 | 338篇 |
1999年 | 320篇 |
1998年 | 221篇 |
1997年 | 190篇 |
1996年 | 218篇 |
1995年 | 145篇 |
1994年 | 167篇 |
1993年 | 150篇 |
1992年 | 244篇 |
1991年 | 258篇 |
1990年 | 294篇 |
1989年 | 321篇 |
1988年 | 286篇 |
1987年 | 259篇 |
1986年 | 254篇 |
1985年 | 277篇 |
1984年 | 191篇 |
1983年 | 171篇 |
1982年 | 109篇 |
1981年 | 96篇 |
1980年 | 82篇 |
1979年 | 117篇 |
1978年 | 86篇 |
1977年 | 74篇 |
1976年 | 86篇 |
1975年 | 85篇 |
1974年 | 99篇 |
1973年 | 91篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Summary The purpose of this study was to evaluate the role of knit structure in underwear on thermoregulatory responses. Underwear manufactured from 100% polypropylene fibres in five different knit structures (1-by-1 rib, fleece, fishnet, interlock, double-layer rib) was evaluated. All five underwear prototypes were tested as part of a prototype clothing system. Measured on a thermal manikin these clothing systems had total thermal resistances of 0.243, 0.268, 0.256, 0.248 and 0.250 m2 · K · W–1, respectively (including a value for the thermal resistance of the ambient environment of 0.104 m2 · K · W–1). Human testing was done on eight male subjects and took place at ambient temperature (T
a)=5°C, dew point temperature (T
dp)=–3.5° C and air velocity (V
a)=0.32 m · s–1. The test comprised a repeated bout of 40-min cycle exercise (315 W · m–2; 52%, SD 4.9% maximal oxygen uptake) followed by 20 min of rest (62 W · m–2). The oxygen uptake, heart rate, oesophageal temperature, skin temperature,T
a,T
dp at the skin and in the ambient air, onset of sweating, evaporation rate, non-evaporated sweat accumulated in the clothing and total evaporative loss of mass were measured. Skin wettedness was calculated. The differences in knit structure of the underwear in the clothing systems resulted in significant differences in mean skin temperature, local and average skin wettedness, non-evaporated and evaporated sweat during the course of the intermittent exercise test. No differences were observed over this period in the core temperature measurements.The views, opinions and/or findings in this report are those of the authors and should not be construed as an official Department of the Army position, policy, or decision, unless so designated by other official documentation 相似文献
92.
Intranasal and inhaled fluticasone propionate for pollen-induced rhinitis and asthma 总被引:3,自引:0,他引:3
Dahl R Nielsen LP Kips J Foresi A Cauwenberge P Tudoric N Howarth P Richards DH Williams M Pauwels R;SPIRA Study Group 《Allergy》2005,60(7):875-881
BACKGROUND: Studies suggest that nasal treatment might influence lower airway symptoms and function in patients with comorbid rhinitis and asthma. We investigated the effect of intranasal, inhaled corticosteroid or the combination of both in patients with both pollen-induced rhinitis and asthma. METHODS: A total of 262 patients were randomized to 6 weeks' treatment with intranasal fluticasone propionate (INFP) 200 microg o.d., inhaled fluticasone propionate (IHFP) 250 microg b.i.d., their combination, or intranasal or inhaled placebo, in a multicentre, double-blind, parallel-group study. Treatment was started 2 weeks prior to the pollen season and patients recorded their nasal and bronchial symptoms twice daily. Before and after 4 and 6 weeks' treatment, the patients were assessed for lung function, methacholine responsiveness, and induced sputum cell counts. RESULTS: Intranasal fluticasone propionate significantly increased the percentages of patients reporting no nasal blockage, sneezing, or rhinorrhoea during the pollen season, compared with IHFP or intranasal or inhaled placebo. In contrast, only IHFP significantly improved morning peak-flow, forced expiratory volume in 1 second (FEV1) and methacholine PD20, and the seasonal increase in the sputum eosinophils and methacholine responsiveness. CONCLUSIONS: In patients with pollen-induced rhinitis and asthma, the combination of intranasal and IHFP is needed to control the seasonal increase in nasal and asthmatic symptoms. 相似文献
93.
Three males with Robertsonian translocations were found in a sample of 1115 males examined for military service. One was a 14/15 translocation, and two were 13/14 translocations. One was spontaneous and two familial. The segregation rate of the translocations did not deviate significantly from unity in the sibships where the mother was the carrier, whereas all five children had the translocation in the two sibships where the father was the carrier. There were no abortions and no aneuploid chromosome abnormalities in the progeny of carriers with D/D translocation. There were no indications of any association between the D/D translocations and physical or mental development. 相似文献
94.
95.
96.
To elevate effects of carbon dioxide (CO2) retention by way of an increased respiratory load during submaximal exercise (150 W), the concentration changes of oxy‐ (ΔHbO2) and deoxy‐haemoglobin (ΔHb) of active muscles and the brain were determined by near‐infrared spectroscopy (NIRS) in eight healthy males. During exercise, pulmonary ventilation increased to 33 (28–40) L min–1 (median with range) with no effect of a moderate breathing resistance (reduction of the pneumotach diameter from 30 to 14 and 10 mm). The end‐tidal CO2 pressure (PETCO 2) increased from 45 (42–48) to 48 (46–58) mmHg with a reduction of only 1% in the arterial haemoglobin O2 saturation (SaO 2). During control exercise (normal breathing resistance), muscle and brain ΔHbO2 were not different from the resting levels, and only the leg muscle ΔHb increased (4 (–2–10) μM , P < 0.05). Moderate resistive breathing increased ΔHbO2 of the intercostal and vastus lateralis muscles to 6 ± (–5–14) and 1 (–7–9) μM (P < 0.05), respectively, while muscle ΔHb was not affected. Cerebral ΔHbO2 and ΔHb became elevated to 6 (1–15) and 1 (–1–6) μM by resistive breathing (P < 0.05). Resistive breathing caused an increased concentration of oxygenated haemoglobin in active muscles and in the brain. The results indicate that CO2 influences blood flow to active skeletal muscle although its effect appears to be smaller than for the brain. 相似文献
97.
98.
O. Ravlo V. Bach H. Lybecker J. T. Møller M. Werner H. K. Nielsen 《Acta anaesthesiologica Scandinavica》1987,31(4):317-319
As part of a training programme for younger doctors, two commercially available, emergency cricothyroidotomy sets were evaluated. Prior to the surgical procedure, half of the doctors in each group received an audiovisual lesson. In a simulated but realistic emergency situation, involving autopsy material, cricothyroidotomy was performed utilizing either the "Nutrake" or the "Gentofte" system. The audiovisual lesson increased the speed and the success rate of the doctors performing this procedure as well as strengthening their confidence. Both systems allowed positive pressure ventilation. The participating doctors achieved a higher success rate at a faster speed with the "Nutrake" set. 相似文献
99.
100.
Angela B. Smith Cleo A. Samuel Sean D. McCabe Allison Deal Mattias Jonsson Dana E. Mueller Zahra M. Mahbooba Antonia V. Bennett Arlene E. Chung Matthew E. Nielsen Hung-Jui Tan Eric Wallen Raj Pruthi Andrew Wang Ethan Basch Bryce B. Reeve Ronald C. Chen 《Urologic oncology》2021,39(1):77.e1-77.e8
ObjectiveTo assess the feasibility of enrollment and collecting patient-reported outcome (PRO) data as part of routine clinical urologic care for bladder and prostate cancer patients and examine overall patterns and racial variations in PRO use and symptom reports over time.Subjects/Patients and MethodsWe recruited 76 patients (n = 29 Black and n = 47 White) with prostate or bladder cancer at a single, comprehensive cancer center. The majority of prostate cancer patients had intermediate risk (57%) disease and underwent either radiation or prostatectomy. Over half (58%) of bladder cancer patients had muscle invasive disease and underwent cystectomy.Patients were asked to complete PRO symptom surveys using their preferred mode [web- or phone-based interactive voice response (IVR)]. Symptom summary reports were shared with providers during visits. Surveys were completed at 3 time points and assessed urinary, sexual, gastrointestinal, anxiety/depression, and sleep symptoms. Feasibility of enrollment and survey completion were calculated, and linear mixed effects models estimated differences in outcomes by race and time.ResultsSixty three percent of study participants completed all PRO measures at all 3 time points. Black patients were more likely to select IVR as their survey mode (40% vs. 13%, P < 0.05), and less likely to complete all surveys (55% vs. 74%, P = 0.13). Patients using IVR were also less likely to complete all surveys (41% vs. 69%, P = 0.046).ConclusionsReported preferences for survey mode and completion rates differ by race, which may influence survey completion rates and highlight potential obstacles for equitable implementation of PROs into clinical care. 相似文献