全文获取类型
收费全文 | 172853篇 |
免费 | 9933篇 |
国内免费 | 436篇 |
专业分类
耳鼻咽喉 | 2264篇 |
儿科学 | 5570篇 |
妇产科学 | 3638篇 |
基础医学 | 23487篇 |
口腔科学 | 7693篇 |
临床医学 | 12719篇 |
内科学 | 38747篇 |
皮肤病学 | 4364篇 |
神经病学 | 14460篇 |
特种医学 | 5289篇 |
外国民族医学 | 26篇 |
外科学 | 21154篇 |
综合类 | 1407篇 |
现状与发展 | 1篇 |
一般理论 | 63篇 |
预防医学 | 18085篇 |
眼科学 | 3189篇 |
药学 | 10453篇 |
中国医学 | 694篇 |
肿瘤学 | 9919篇 |
出版年
2023年 | 934篇 |
2022年 | 2011篇 |
2021年 | 3753篇 |
2020年 | 2515篇 |
2019年 | 3516篇 |
2018年 | 4909篇 |
2017年 | 3690篇 |
2016年 | 3455篇 |
2015年 | 4021篇 |
2014年 | 5504篇 |
2013年 | 6957篇 |
2012年 | 10847篇 |
2011年 | 11350篇 |
2010年 | 5749篇 |
2009年 | 5146篇 |
2008年 | 8776篇 |
2007年 | 9345篇 |
2006年 | 8675篇 |
2005年 | 8955篇 |
2004年 | 8401篇 |
2003年 | 7666篇 |
2002年 | 5708篇 |
2001年 | 4959篇 |
2000年 | 4952篇 |
1999年 | 4360篇 |
1998年 | 1544篇 |
1997年 | 1284篇 |
1996年 | 1275篇 |
1995年 | 1081篇 |
1994年 | 1075篇 |
1993年 | 978篇 |
1992年 | 2656篇 |
1991年 | 2569篇 |
1990年 | 2341篇 |
1989年 | 2348篇 |
1988年 | 2109篇 |
1987年 | 1957篇 |
1986年 | 1833篇 |
1985年 | 1756篇 |
1984年 | 1253篇 |
1983年 | 1012篇 |
1982年 | 566篇 |
1981年 | 514篇 |
1980年 | 493篇 |
1979年 | 920篇 |
1978年 | 604篇 |
1977年 | 475篇 |
1975年 | 542篇 |
1974年 | 540篇 |
1973年 | 541篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
992.
993.
994.
H J van de Wiel E Lebret W K van der Lingen H C Eerens L H Vaas M J Leupen 《Toxicology and industrial health》1990,6(5):103-115
Several national and international health organizations have derived concentration levels below which adverse effects on men are not expected or levels below which the excess risk for individuals is less than a specified value. For every priority pollutant indoor concentrations below this limit are considered "healthy." The percentage of Dutch homes exceeding such a limit is taken as a measure of indoor air quality for that component. The present and future indoor air quality of the Dutch housing stock is described for fourteen air pollutants. The highest percentages are scored by radon, environmental tobacco smoke, nitrogen dioxide from unvented combustion, and the potential presence of housedust mite and mould allergen in damp houses. Although the trend for all priority pollutants is downward the most serious ones remain high in the coming decades if no additional measures will be instituted. 相似文献
995.
Familial occurrence of gastric cancer in the 2-year experience of a population-based registry 总被引:17,自引:0,他引:17
G Zanghieri C Di Gregorio C Sacchetti R Fante R Sassatelli G Cannizzo A Carriero M Ponz de Leon 《Cancer》1990,66(9):2047-2051
The authors studied the familial occurrence of tumors in 154 individuals with gastric cancer by reviewing the clinical data and the genealogical tree of all patients registered in 1986 through 1987 in the Local Health Care District of Modena, Italy, for cancer of the stomach. Crude and age-adjusted (world population) incidence rates of gastric cancer were 34.0 and 21.4 new cases/100,000/year, respectively, in men, and 24.5 and 10.9 in women, respectively. Among first-degree relatives of the registered patients there were 30 cases of gastric carcinoma versus 15 cases in a control group matched for age and sex (Mantel-Haenszel odds ratio [M-H OR] 3.14, P less than 0.01). This excess of gastric neoplasms was observed in siblings (17 versus 7, M-H OR 4.33, P less than 0.02) but not in parents (13 versus 8, not significant). Besides gastric cancer, there was no significant excess of other type of tumors in case families. The familial occurrence of gastric cancer tended to be more frequent in patients with "diffuse" carcinoma (52%) than in subjects with "intestinal" cancer (33%), although the difference was not statistically significant. In conclusion, the current investigation suggests that a "family history" for gastric neoplasms is usually observed in approximately 10% to 15% of the registered cases. As already described for other common malignancies, therefore, the familial occurrence of gastric carcinoma suggests the existence of a genetic susceptibility to cancer of the stomach, at least in a fraction of these patients. 相似文献
996.
Endoscopic cordectomy. a proposal for a classification by the Working Committee, European Laryngological Society 总被引:6,自引:0,他引:6
M. Remacle Hans E. Eckel Antonio Antonelli Daniel Brasnu Dominique Chevalier Gerhard Friedrich Jan Olofsson Heinrich H. Rudert Walter Thumfart Marco de Vincentiis Thomas P. U. Wustrow 《European archives of oto-rhino-laryngology》2000,257(4):227-231
The European Laryngological Society is proposing a classification of different laryngeal endoscopic cordectomies in order
to ensure better definitions of postoperative results. We chose to keep the word “cordectomy” even for partial resections
because it is the term most often used in the surgical literature. The classification comprises eight types of cordectomies:
a subepithelial cordectomy (type I), which is resection of the epithelium; a subligamental cordectomy (type II), which is
a resection of the epithelium, Reinke’s space and vocal ligament; transmuscular cordectomy (type III), which proceeds through
the vocalis muscle; total cordectomy (type IV); extended cordectomy, which encompasses the contralateral vocal fold and the
anterior commissure (type Va); extended cordectomy, which includes the arytenoid (type Vb); extended cordectomy, which encompasses
the subglottis (type Vc); and extended cordectomy, which includes the ventricle (type Vd). Indications for performing those
cordectomies may vary from surgeon to surgeon. The operations are classified according to the surgical approach used and the
degree of resection in order to facilitate use of the classification in daily practice. Each surgical procedure ensures that
a specimen is available for histopathological examination.
Received: 29 December 1998 / Accepted: 2 July 1999 相似文献
997.
Lisanne E. de Koning Jessica Warnink-Kavelaars Marion A. van Rossum Diederik Bosman Leonie A. Menke Fransiska Malfait Rosa de Boer Jaap Oosterlaan Raoul H. H. Engelbert Lies Rombaut And the Pediatric Heritable Connective Tissue Disorders Study Group 《American journal of medical genetics. Part A》2023,191(7):1792-1803
The aim of the present study was to investigate the nature and prevalence of nonspecific somatic symptoms, pain and catastrophizing in children with Heritable Connective Tissue Disorders (HCTD), and to determine their association with disability. This observational, multicenter study included 127 children, aged 4–18 years, with Marfan syndrome (MFS) (59%), Loeys-Dietz syndrome (LDS) (8%), Ehlers-Danlos syndromes (EDS) (12%) and hypermobile Ehlers-Danlos syndrome (hEDS) (23%). The assessments included the Children's Somatization Inventory or parent proxy (CSI, PCSI), pain visual-analogue scale (VAS), SUPERKIDZ body diagram, Pain Catastrophizing Scale Child or parent proxy (PCS-C, PCS-P) and Childhood Health Assessment Questionnaire (CHAQ-30). Data from children aged ≥8 years were compared to normative data. In children ≥ 8 years (n = 90), pain was present in 59%, with a median of 4 (IQR = 3–9) pain areas. Compared to normative data, the HCTD group reported significantly higher on the CSI (p ≤ 0.001, d = 0.85), VAS pain intensity (p ≤ 0.001, d = 1.22) and CHAQ-30 (p ≤ 0.001, d = 1.16) and lower on the PCS-C (p = 0.017, d = −0.82) and PCS-P (p ≤ 0.001, d = −0.49). The intensity of nonspecific somatic symptoms and pain explained 45% of the variance in disability (r2 = 0.45 F(2,48) = 19.70, p ≤ 0.001). In children ≤ 7 years (n = 37), pain was present in 35% with a median of 5(IQR = 1–13) pain areas. The mean(SD) VAS scores for pain intensity was 1.5(2.9). Functional disability was moderately correlated to the number of pain areas (r = 0.56, p ≤ 0.001), intensity of nonspecific somatic symptoms (r = 0.63, p ≤ 0.001) and pain (r = 0.83, p ≤ 0.001). In conclusion, this study supports the need for comprehensive assessment of nonspecific somatic symptoms, pain, and disability in children with HCTD to allow tailored treatment. 相似文献
998.
Haveman-Nies A de Groot LC Van Staveren WA 《The journal of nutrition, health & aging》1997,1(3):151-155
Dehydration is a common fluid disorder which occurs in residents, hospitalised and community-dwelling elderly people. In this study the intake of water and fluids of community-dwelling elderly Europeans is presented in relation to risk factors of dehydration: mental state, ability to perform activities of daily living (ADL), medicine use and body composition. As part of the SENECA-study of 1993, data were collected from a random age-stratified sample (birth cohorts 1913-1918) of inhabitants of small traditional towns in Europe. Food intake data were collected by using the dietary history method. The study population consisted of 629 men and 696 women of the following towns: Hamme/Belgium, Roskilde/Denmark, Haguenau/France, Romans/France, Padua/Italy, Culemborg/the Netherlands, Lisbon/Portugal, Yverdon/Switzerland, Marki/Poland and Ballymoney-Limavady-Portstewart/Northern Ireland/United Kingdom. Fluid intake of elderly people varied between the towns of Europe and between men and women. A high percentage of the female population had a water intake below the cut-off value of 1,700 g. In most towns about 70 percent of daily water intake came from the food groups 'Milk products', 'Alcoholic drinks', 'Juices' and 'Other non-alcoholic drinks'. The consumption of 'Other non-alcoholic drinks' contributed most to daily fluid intake. In the total female population, women with the lowest water intake (first tertile) scored negatively on factors influencing fluid intake (mental state, ADL) in comparison to women of the second and third tertile. However, in the distinct towns no unequivocal relationship emerged between those factors and fluid intake. Yet, women were found to be at higher risk of dehydration because of much lower water intakes than men and because of the overall relationship between a low fluid intake and a poor mental state and ADL problems. 相似文献
999.
Annaert Pieter Kinget Renaat Naesens Lieve de Clercq Erik Augustijns Patrick 《Pharmaceutical research》1997,14(4):492-496
Purpose. To evaluate intestinal transport, uptake and metabolism characteristics of the bis(pivaloyloxymethyl)-ester [bis(POM)-ester] of the antiviral agent 9-(2-phosphonylmethoxyethyl)adenine [PMEA].
Methods. Intestinal transport, uptake and metabolism of bis(POM)-PMEA were studied using an in vitro cell culture system of the intestinal mucosa (Caco-2 monolayers). Concentrations of bis(POM)-PMEA and its metabolites mono(POM)-PMEA and PMEA were determined using a reversed-phase HPLC method. Enzymatic stability of bis(POM)-PMEA was evaluated by incubation with purified liver carboxylesterase, homogenates of Caco-2 cells and scraped pig small intestinal mucosa.
Results. The use of bis(POM)-PMEA as a prodrug of PMEA resulted in a significant increase in transport of total PMEA [bis(POM)-PMEA, mono(POM)-PMEA and PMEA] across Caco-2 monolayers. While transepithelial transport of PMEA (500 M) was lower than 0.1% during a 3 hr incubation period, transport of total PMEA after addition of bis(POM)-PMEA (100 M) amounted to 8.8% over the same incubation period. Only 23% of the amount transported appeared as intact bis-ester at the basolateral side, while 33% of this amount was free PMEA and 44% was mono(POM)-PMEA, suggesting susceptibility of the prodrug to chemical and enzymatic degradation. Uptake studies revealed that only negligible amounts of bis(POM)-PMEA (< 0.2%) were present inside the cells. Very high intracellular concentrations of PMEA were found 1.2 mM, after a 3 hr incubation with 50 M bis(POM)-PMEA), which suggests that PMEA was trapped inside the cells probably due to its negative charge. This explains that efflux of PMEA was relatively slow (25% of the intracellular amount in 3 hr). Enzymatic degradation of the prodrug by carboxylesterase was confirmed by incubation of bis(POM)-PMEA with purified enzyme (Km = 87 M and Vmax = 9.5 M/min). Incubation of bis(POM)-PMEA (10 M) with cell homogenate of Caco-2 monolayers and pig small intestinal mucosa produced similar degradation profiles.
Conclusions. The use of the bis(POM)-prodrug significantly enhances the intestinal permeability of PMEA. Intracellular trapping of PMEA in the intestinal mucosa may result in slow release of PMEA to the circulation after oral administration of bis(POM)-PMEA. 相似文献
1000.
de la Cour L 《Health & place》1997,3(2):131-141
Drawing on the detailed information contained in patient case files, this study explores women patients' perceptions of the Ontario Hospital, Cobourg, a psychiatric facility for women which operated from 1920 to 1974. The paper concludes that, while twentieth-century psychiatry promoted an image of asylums as modern medical facilities, women patients continued to view these institutions as 'crazy houses', 'havens' and 'prisons'. It was not until the 1950s and 1960s, the eve of the decline of the authority of scientific psychiatry, that some women patients began to conceive of psychiatric hospitals as 'medical' facilities where therapeutic care could be sought. 相似文献