全文获取类型
收费全文 | 15028篇 |
免费 | 1168篇 |
国内免费 | 281篇 |
专业分类
耳鼻咽喉 | 163篇 |
儿科学 | 416篇 |
妇产科学 | 156篇 |
基础医学 | 757篇 |
口腔科学 | 230篇 |
临床医学 | 876篇 |
内科学 | 3315篇 |
皮肤病学 | 303篇 |
神经病学 | 1083篇 |
特种医学 | 245篇 |
外科学 | 1400篇 |
综合类 | 1333篇 |
预防医学 | 4508篇 |
眼科学 | 226篇 |
药学 | 531篇 |
2篇 | |
中国医学 | 52篇 |
肿瘤学 | 881篇 |
出版年
2024年 | 16篇 |
2023年 | 216篇 |
2022年 | 453篇 |
2021年 | 603篇 |
2020年 | 559篇 |
2019年 | 658篇 |
2018年 | 714篇 |
2017年 | 528篇 |
2016年 | 504篇 |
2015年 | 538篇 |
2014年 | 1176篇 |
2013年 | 1111篇 |
2012年 | 865篇 |
2011年 | 981篇 |
2010年 | 815篇 |
2009年 | 839篇 |
2008年 | 791篇 |
2007年 | 761篇 |
2006年 | 626篇 |
2005年 | 531篇 |
2004年 | 363篇 |
2003年 | 316篇 |
2002年 | 265篇 |
2001年 | 253篇 |
2000年 | 216篇 |
1999年 | 193篇 |
1998年 | 162篇 |
1997年 | 145篇 |
1996年 | 112篇 |
1995年 | 103篇 |
1994年 | 90篇 |
1993年 | 85篇 |
1992年 | 102篇 |
1991年 | 85篇 |
1990年 | 84篇 |
1989年 | 51篇 |
1988年 | 59篇 |
1987年 | 53篇 |
1986年 | 39篇 |
1985年 | 77篇 |
1984年 | 49篇 |
1983年 | 40篇 |
1982年 | 35篇 |
1981年 | 46篇 |
1980年 | 27篇 |
1979年 | 32篇 |
1978年 | 20篇 |
1977年 | 19篇 |
1976年 | 25篇 |
1975年 | 21篇 |
排序方式: 共有10000条查询结果,搜索用时 31 毫秒
161.
Nikola Bradarić Volga Punda-Polić lvo Milas Ivo Ivić Dušanka Grgić Nikola Radošević lvo Petrić 《European journal of epidemiology》1996,12(4):409-412
Two outbreaks of typhoid fever caused by Salmonella typhi of the same phagotype (A, biotype II) and antibiotic susceptibility are reported. Both occurred during the war in Bosnia and Herzegovina. The first outbreak appeared among the refugees from the town of Jajce. The second outbreak appeared among the inhabitants in the village of Vidosi near Livno. This report describes main clinical, epidemioloigcal and laboratory findings for 22 patients treated in Split University Hospital, Croatia, in the period November 1992–January 1993. Possible epidemiological connections between those two outbreaks are discussed. 相似文献
162.
A prevalence survey of movement disorders, epilepsy, hypertension and smoking was undertaken in Vejer de la Frontera, Southern Spain in 1988. A validated screening instrument designed for door-to-door tracing of specific disorders was used. Neurological diagnoses were based on: (1) direct anamnesis and examination by a senior neurologist; (2) perusal of existing medical records; and (3) in a proportion of cases, a hospital-based complementary study. This experience suggests that, while door-to-door surveys of neurological disorders have focused on multiple major outcomes: (1) scientific and logistic reasons can exist for screening for specific neurological disorders, and (2) scientific and public health-related interventional objectives can be combined advantageously when such costly investigations are conducted. 相似文献
163.
The effect of smoking at different life stages on bone mineral density in elderly men and women 总被引:6,自引:2,他引:4
D. P. Kiel MD Y. Zhang M. T. Hannan J.J Anderson J. A. Baron D. T. Felson 《Osteoporosis international》1996,6(3):240-248
To assess the effect of smoking on bone mineral density (BMD) at different life stages, to examine whether the effect of smoking differs between men and women, and to discover whether its effect in women differs according to history of estrogen use, a cohort study was carried out with single cross-section measurement of BMD by single and dual photon absorptiometry. The setting was the Framingham Study, a population-based cohort study with over 40 years prospectively collected data on smoking. Subjects (n=1164) consisted of cohort members participating in the 20th biennial Framingham examination (1988–1989). The measurements included in the study were BMD measured at the hip, spine and radius, smoking history ascertained at all Framingham Study examinations since 1948, and other factors affecting BMD (age, weight, estrogen use, caffeine use, alcohol use and physical activity). Neither current smoking, recent (last 10 years) smoking, nor early adulthood smoking resulted in significantly lower BMD at any skeletal site among women who had not taken estrogen. Among women who had taken estrogen, BMD at most sites was lower among current or recent smokers, although the small numbers of smokers made it difficult to find significant differences at all skeletal sites. Among men, a consistently lower BMD at all skeletal sites was observed for smokers regardless of when in their life they smoked (4–15.3% lower), although the effect of smoking during early adulthood was of a lesser magnitude (4–8% lower). Former male smokers who had quit <10 years ago had lower BMD than men who had quit 10 years ago. In conclusion, in women who had used estrogen, BMD was lower in current or recent smokers than it was in non-smokers. In men, smoking at any stage of life had adverse effects on the skeleton that was independent of weight, alcohol or caffeine use, implying other mechanisms for smoking's effect on bone. 相似文献
164.
G. Dhom 《Journal of cancer research and clinical oncology》1983,106(3):210-218
Summary The worldwide incidence of prostate cancer differs greatly. The black population of the USA is at the head, while the Asian populations have the lowest incidence and mortality rates. Comparative geographic-pathologic autopsy studies on frequency and growth type of latent prostate carcinomas show that in populations with a lower incidence, for example Japan and Singapore, latent carcinomatous foci are not considerably rarer than in regions with high incidence. However, obvious differences are seen when comparing the size of the foci and the growth types. In countries with low incidence and mortality rate, the foci of the latent prostate carcinoma are small and show a slight proliferating tendency, whereas in countries with high incidence and mortality rate, they are frequently larger and more aggressive. Consequently, the different incidence of prostate cancer is not based on different initiation of malignant transformation, but on different promoting factors. In histologic-bioptical specimens from regions with high incidence and mortality rate, pluriform tumor types of malignancy grade G III and G II prevail. Definite causes of prostate cancer could not be detected by case control and migration studies up to now.Supported by the campaign Kampf dem Krebs e.V. der Deutschen Krebsgesellschaft 相似文献
165.
Failure to find a relationship between mnestic skills of octogenarians and aluminum in drinking water 总被引:3,自引:0,他引:3
A. Wettstein J. Aeppli K. Gautschi M. Peters 《International archives of occupational and environmental health》1991,63(2):97-103
Summary High concentrations of aluminum (>80 g/l) in drinking water have been related to an elevated incidence of Alzheimer's disease. Mnestic and naming skills of residents living for >15 years in districts with high (98 g/l) or low (4 g/l) aluminum concentrations [Al] in the drinking water were evaluated in a population survey by examining 800 residents aged 81 to 85 using the mnestic subtest of the Mini Mental Status test (Zurich variant). The mnestic and naming performance of the octogenarians did not differ between the high- and low-content-areas. Since 73% of dementias are at least partly caused by Alzheimer's disease in the area examined and because the short test used discriminates demented from healthy octagenarians as well as tests involving extensive examinations, the findings of this study suggest with a high probability that the [Al] of drinking water is not an essential factor in the pathogenesis of senile dementia. The serum [Al] the urinary [Al] and the urinary [Al]/creatinine ratio were measured twice in ten clinically diagnosed Alzheimer patients and ten controls in both areas. No significant difference was found, which confirms the negative epidemiological findings.Parts of this study were presented at the joint meeting of the Swedish and Swiss Neurological Association in Interlaken, Switzerland, on May 22, 1990 相似文献
166.
Progetto ATENA,A study on the etiology of major chronic diseases in women: Design,rationale and objectives 总被引:2,自引:0,他引:2
S. Panico R. Dello Iacovo E. Celentano R. Galasso P. Muti M. Salvatore M. Mancini 《European journal of epidemiology》1992,8(4):601-608
In spite of their important impact on populations, a number of diseases - all types of cancer and coronary heart disease in women - are rare events for statistical analysis and often analyzed in designs affected by selection and information biases, such as case-control studies. Large cohort studies based on the storage of biological specimens appear to be the most suitable solution for identifying risks for those diseases.Progetto ATENA, a study on the etiology of major chronic diseases in women is based on this design. Ten thousand women, aged 30–69 years, living in the area of the city of Naples, free of cancer and cardiovascular disease, are being recruited over a four-year period. Ten per cent of the cohort is being randomly selected from the electoral roles, the rest will be volunteers.Information on dietary habits, reproductive history, familiarity for chronic disease, active smoking habits and passive smoking exposure, physical activity, and socio-demographic data are being collected. Clinical data such as blood pressure, anthropometry, and electrocardiogram are also taken. All the participants provide biological samples of blood (fasting drawing) and urine (timed morning spot). The biological samples are processed in order to explore the main areas under study (nutritional markers, metabolism, endocrinology, genetics, environmental exposure markers, thrombogenesis). The samples are stored in liquid nitrogen (–196° C) as soon as the blood and urine processing have been finished. An appropriate follow-up information system on the health status of the participants is being set up to estimate incidence and mortality rates.Corresponding author. 相似文献
167.
J. Turk M.D. M. Kenda I. Kranjec 《Journal of molecular medicine (Berlin, Germany)》1991,69(14):674-678
Summary Malignant primary tumors of the pericardium are rare. The autors present two male patients, aged 44 and 67 years, not exposed to asbestos, who died from pericardial mesothelioma. Repeated evacuation of fluid from the pericardium due to cardiac tamponade failed to reveal the cause of pericarditis. In one case, the diagnosis was made on surgical exploration, and in the other, at autopsy. A significant difference between benign and malignant pericardial effusion was observed. In cases of pericardial mesothelioma, symptoms of epicardial involvement cannot be attributed solely to the hindered inflow and cardiac tamponade, but also to congestive heart failure due to myocardial infiltration. In one patient, temporary improvement was achieved, first by pronisone therapy and then by radiotherapy. 相似文献
168.
Is sleep-disordered breathing an independent risk factor for hypertension in the general population (13,057 subjects)? 总被引:27,自引:0,他引:27
Ohayon MM Guilleminault C Priest RG Zulley J Smirne S 《Journal of psychosomatic research》2000,48(6):593-601
Objective: Sleep-disordered breathing has been hypothesized to have a close relationship with hypertension but previous studies have reported mixed results. This is an important health issue that requires further clarification because of the potential impact on the prevention and control of hypertension.Methods: The relationship between hypertension and three forms of sleep-disordered breathing (chronic snoring, breathing pauses and obstructive sleep apnea syndrome (OSAS)) was assessed using representative samples of the non-institutionalized population of the UK, Germany and Italy (159 million inhabitants). The samples were comprised of 13,057 individuals aged 15–100 years who were interviewed about their sleeping habits and their sleep symptoms over the telephone using the Sleep-EVAL system.Results: OSAS was found in 1.9% (95% CI: 1.2% to 2.3%) of the UK sample, 1.8% (95% CI: 1.4% to 2.2%) of the German sample and 1.1% (95% CI: 0.8% to 1.4%) of the Italian sample. OSAS was an independent risk factor (odds ratio (OR): 9.7) for hypertension after controlling for possible confounding effects of age, gender, obesity, smoking, alcohol consumption, life stress, and, heart and renal disease.Conclusions: Results from three of the most populated countries in Western Europe indicate that OSAS is an independent risk factor for hypertension. Snoring and breathing pauses during sleep appeared to be non-significant predictive factors. 相似文献
169.
目的 通过对一起输入性传染源引发的院内严重急性呼吸道综合征(SARS)感染暴发进行调查,找出其流行特点,探讨发病规律和流行因素,为预防和控制院内SARS感染提供参考。方法通过座谈了解、查阅病案和查看感染现场,描述整个感染传播过程和各因素与发病间的关系。结果 该院3月18日接诊了一名发热患后,科内5名员工相继发病,罹患率达21.74%,整个感染过程可见清晰的传播链,感染与无防护密切接触、室内小环境空气质量差有关。发病潜伏期平均10天以上,平均病程49.4天。经采取隔离、消毒措施后,未见新发病。结论 该院内SARS感染首例传染源为输入性;急诊科护士是感染的高危人群;无防护近距离密切接触是SARS的主要传播方式。 相似文献
170.
Kroke A Klipstein-Grobusch K Bergmann MM Weber K Boeing H 《Calcified tissue international》2000,66(1):5-10
Body mass is known to be related to measures of bone mineral density (BMD) as well as to parameters of quantitative ultrasound
(US). To examine the effect of the body compartment's fat mass and lean body mass on quantitative ultrasonic bone parameters,
data from a sample of 3241 German women were analyzed. Anthropometric measures, including skinfold thickness, were obtained
from standardized measurements, and fat and lean body mass were derived from classical regression formulas based on skinfold
measurements. Ultrasonic bone measurements were performed on the right os calcis, and speed of sound (SOS) and broadband ultrasound
attenuation (BUA) were determined. Women were grouped into pre- and postmenopausal status; postmenopausal women were further
stratified into ever and never hormone-replacement user. Correlation analysis indicated lean body mass to be stronger correlated
with BUA than fat mass in both pre- (r = 0.23; P= 0.0001) and postmenopausal women with (r = 0.19; P= 0.0001) and without hormone replacement therapy (HRT) (r = 0.26; p = 0.0001). SOS demonstrated very small or no associations
with body mass or its components. Multiple linear regression models were used to describe the relationship among body weight,
fat mass, and lean body mass on BUA after adjustment for confounding variables. Both in pre- and postmenopausal women lean
body mass was more strongly related to BUA than fat mass. However, body mass measures explained only small amounts of the
overall variance in BUA (R2= 1–3% in premenopausal women; R2= 1% postmenopausal with HRT; R2= 4–5% in postmenopausal women without HRT). In conclusion, the strong influence of body mass and its components previously
reported for BMD was not observed for quantitative ultrasonic bone parameters.
Received: 5 January 1999 / Accepted: 1 July 1999 相似文献