全文获取类型
收费全文 | 574篇 |
免费 | 49篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 73篇 |
儿科学 | 20篇 |
妇产科学 | 7篇 |
基础医学 | 97篇 |
口腔科学 | 23篇 |
临床医学 | 72篇 |
内科学 | 90篇 |
皮肤病学 | 12篇 |
神经病学 | 79篇 |
特种医学 | 9篇 |
外科学 | 56篇 |
综合类 | 1篇 |
预防医学 | 34篇 |
眼科学 | 3篇 |
药学 | 14篇 |
肿瘤学 | 35篇 |
出版年
2023年 | 2篇 |
2022年 | 2篇 |
2021年 | 7篇 |
2020年 | 7篇 |
2019年 | 12篇 |
2018年 | 5篇 |
2017年 | 11篇 |
2016年 | 19篇 |
2015年 | 13篇 |
2014年 | 15篇 |
2013年 | 25篇 |
2012年 | 25篇 |
2011年 | 25篇 |
2010年 | 12篇 |
2009年 | 23篇 |
2008年 | 43篇 |
2007年 | 32篇 |
2006年 | 39篇 |
2005年 | 47篇 |
2004年 | 50篇 |
2003年 | 37篇 |
2002年 | 27篇 |
2001年 | 12篇 |
2000年 | 17篇 |
1999年 | 8篇 |
1998年 | 3篇 |
1997年 | 8篇 |
1996年 | 3篇 |
1995年 | 2篇 |
1994年 | 4篇 |
1993年 | 3篇 |
1992年 | 6篇 |
1991年 | 5篇 |
1990年 | 7篇 |
1989年 | 11篇 |
1988年 | 10篇 |
1987年 | 11篇 |
1986年 | 2篇 |
1985年 | 1篇 |
1984年 | 6篇 |
1983年 | 1篇 |
1982年 | 4篇 |
1981年 | 5篇 |
1980年 | 4篇 |
1979年 | 8篇 |
1978年 | 2篇 |
1977年 | 3篇 |
1967年 | 1篇 |
排序方式: 共有625条查询结果,搜索用时 31 毫秒
1.
Effect of impact exercise on bone mineral density in elderly women with low BMD: a population-based randomized controlled 30-month intervention 总被引:4,自引:3,他引:1
Raija Korpelainen Sirkka Keinänen-Kiukaanniemi Jorma Heikkinen Kalervo Väänänen Juha Korpelainen 《Osteoporosis international》2006,17(1):109-118
Evidence of the effect of exercise on bone loss comes mainly from studies in voluntary postmenopausal women, and no population-based, long-term interventions have been performed. The purpose of this population-based, randomized, controlled trial was to determine the effect of long-term impact exercise on bone mass at various skeletal sites in elderly women with low bone mineral density (BMD) at the radius and hip. Participants ( n =160) were randomly assigned to 30 months either of supervised and home-based impact exercise training or of no intervention. The primary outcome measures were femoral neck, trochanter and total hip BMD, and the secondary outcomes were bone density measures at the radius and calcaneum. Outcomes were assessed at baseline, 12 months and 30 months using blinded operators. The analyses were performed on an intention-to-treat analysis. Mean femoral neck and trochanter BMD decreased in the control group [–1.1%, 95% confidence interval (CI) –0.1% to –2.1% and –1.6%, 95% CI –0.4% to –2.7%], while no change occurred in the exercise group. Mean trochanter BMC decreased more in the control group (–7.7%, 95% CI –9.7% to –5.6% vs. –2.9%, 95% CI –5.3 to –0.9). There were six falls that resulted in fractures in the exercise group and 16 in the control group during the 30-month intervention ( P =0.019). A significant bone loss occurred in both groups at the radius and calcaneum. In multivariate analysis, weight gain was associated with increased BMD and BMC at all femur sites both in the exercise group and in the pooled groups. In conclusion, impact exercise had no effect on BMD, while there was a positive effect on BMC at the trochanter. Exercise may prevent fall-related fractures in elderly women with low bone mass.There was no conflict of interest. 相似文献
2.
Three-year results of bracing in scoliosis 总被引:2,自引:0,他引:2
We treated 107 patients with idiopathic scoliosis with the Boston brace. The primary correction was good in all the curve patterns. The follow-up time after weaning averaged 3 years. The best final result was achieved in thoracic and lumbar curves (mean 2°). The final correction was worse in patients with an initial curve less than 30° when compared with the patients with larger curves. Except the double major curves, there was a positive correlation between the primary correction, duration of the treatment, and the final result. The results in 14 patients with bracing for 12 hours daily did not differ from the remainder. Progression of the initial curve more than 5° after the treatment was noted in 24 patients. Three patients were operated on later because of progression. We conclude that bracing can prevent progress of scoliosis. 相似文献
3.
Saara Tyry Raija Kalimo Markku rimaa Juhani Juntunen Markku Seuri Kimmo Rsnen 《Stress and health》2004,20(4):213-221
The aim of this study was to analyse the influence of gender and children on physicians' stress and burnout and to obtain information on the compromises physicians make between family and work. The study was based on a nationwide survey of 3313 Finnish physicians. The results showed that work was the commonest reason for stress for both male and female physicians. If physicians had children, combining work and family was the commonest reason for stress among the women, but work still remained the commonest reason for stress among the men. The female physicians had made compromises between family and work more often than the male physicians (limited the number of children, delayed having children, given up postgraduate or continuing medical education, worked part‐time because of family, and given up a job because of a spouse's need to move). The female physicians—with or without children—were more likely than the male physicians to experience severe or moderate exhaustion and less likely than the male physicians to experience cynicism as components of burnout. Among both genders of physicians, having children was associated with less cynicism and reduced personal accomplishment, but the children did not affect exhaustion. In conclusion, having children is associated with a lower level of some burnout symptoms. Additional studies are needed to explain the health effects of work–family balance for physicians. Copyright © 2004 John Wiley & Sons, Ltd. 相似文献
4.
Depression-executive dysfunction syndrome in stroke patients. 总被引:6,自引:0,他引:6
Risto Vataja Tarja Pohjasvaara Riitta M?ntyl? Raija Ylikoski Maarit Leskel? Hely Kalska Marja Hietanen Hannu Juhani Aronen Oili Salonen Markku Kaste Antero Lepp?vuori Timo Erkinjuntti 《The American journal of geriatric psychiatry》2005,13(2):99-107
OBJECTIVE: It has been suggested that executive dysfunction could be the core defect in patients with geriatric or vascular depression, and that this depression-dysexecutive syndrome (DES) might be related to frontal-subcortical circuit dysfunction. The authors tested this hypothesis in 158 poststroke patients, of whom 21 had both depression and executive dysfunction. Methods: In this cross-sectional cohort study, a neurological, psychiatric, and neuropsychological examination was carried out 3 months after ischemic stroke, and brain infarcts, white-matter changes, and brain atrophy were recorded by MRI. RESULTS: The 21 patients with DES had significantly more brain infarcts affecting their frontal-subcortical circuit structures than the 137 patients without DES, or the 41 patients with depression but without executive dysfunction. Patients with DES also had more severe depressive symptoms and worse psychosocial functioning, and they coped less well in complex activities of daily living. CONCLUSIONS: DES is a valid concept and may define a subgroup of poststroke patients with frontal-subcortical pathology and with distinct prognosis and treatment options. 相似文献
5.
6.
Lindström M Nevas M Kurki J Sauna-aho R Latvala-Kiesilä A Pölönen I Korkeala H 《Journal of clinical microbiology》2004,42(10):4718-4725
The largest reported outbreak of type C botulism in fur production animals is described. Epidemiological investigation of 117 out of 157 (response rate, 74.5%) farms revealed that 44,130 animals died or were euthanized, while 8,033 animals with milder symptoms recovered. The overall death rate in all animals at risk was 21.7%. The death rates were significantly higher in blue and shadow foxes (24.2 and 27.8%, respectively) than in silver and blue silver foxes and minks (below 4%). All minks had been immunized against botulinum toxin type C. Deaths were associated with feed manufactured by a local processor, 83 of whose customer farms (70.9%) reported dead or sick animals. Five feedlots out of 19 delivered to the farms on the day preceding the onset of the outbreak (day 2) were associated with a death rate higher than 40%. These feedlots consisted of fresh feed processed on day 2 and feed processed 1 day earlier (day 1). In laboratory analysis, the day 2 feed contained botulinum toxin type C (>600 minimum lethal doses/g), while the day 1 feed did not contain toxin. Toxin was not detected in feed raw-material samples. Clostridium botulinum type C was detected by PCR in some feed components and in feed. However, as the feed temperature was continuously 8 degrees C or below and the pH was continuously 5.6 or below according to the manufacturer, it seems unlikely that spore germination and toxin formation occurred during overnight storage. Hence, the events leading to toxin formation were not determined. 相似文献
7.
The relationship between job-related burnout and depressive disorders--results from the Finnish Health 2000 Study 总被引:7,自引:0,他引:7
Ahola K Honkonen T Isometsä E Kalimo R Nykyri E Aromaa A Lönnqvist J 《Journal of affective disorders》2005,88(1):55-62
BACKGROUND: Depression and burnout are common health problems in working populations today. They appear to be interrelated, and the need for their differential diagnosis has been highlighted in many reviews. We analysed the overlap of job-related burnout and depressive disorders, i.e., major depressive disorder, dysthymia, and minor depressive disorder. METHODS: We used the population-based 'Health 2000 Study' in Finland. Our nationally representative sample comprised 3276 employees aged 30-64 years. Burnout was assessed with the Maslach Burnout Inventory-General Survey. Diagnoses of depressive disorders were based on the Composite International Diagnostic Interview. RESULTS: Burnout and depressive disorders were clearly related. The risk of depressive disorders, especially major depressive disorder (12-month prevalence), was greater when burnout was severe. Half of the participants with severe burnout had some depressive disorder. Those with a current major depressive episode suffered from serious burnout more often than those who had suffered a major depressive episode earlier. LIMITATIONS: This study was cross-sectional. CONCLUSIONS: The concepts of burnout and depression complement each other and cover partly overlapping phenomena. Depressive disorders are related to job-related burnout, particularly when it is severe. A current major depressive episode is likely to be associated with the experience of burnout. When encountering working patients, it is recommended to assess both the occurrence of burnout and of depressive disorders. 相似文献
8.
Comparison of the nasal bacterial floras in two groups of healthy subjects and in patients with acute maxillary sinusitis. 总被引:7,自引:1,他引:7
下载免费PDF全文
![点击此处可从《Journal of clinical microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
H R Jousimies-Somer S Savolainen J S Ylikoski 《Journal of clinical microbiology》1989,27(12):2736-2743
The nasal bacterial flora was studied in 183 healthy men entering military service (entry group), 103 healthy recruits in service (service group), and 185 recruits with acute maxillary sinusitis. The 267 nasal and ipsilateral sinus aspirate findings in the same patients with acute maxillary sinusitis were compared pairwise. In the entry group presumed sinus pathogens were only rarely isolated from the nasal cavities: Haemophilus influenzae in 4%, Streptococcus pneumoniae in 1%, Branhamella catarrhalis in 3%, and Streptococcus pyogenes in 0%. The corresponding isolation frequencies in the service group were 19, 13, 3, and less than 1%, respectively, and those in the group with acute maxillary sinusitis were 61, 25, 7, and 6%, respectively. Suppression of the major components of the normal nasal flora, Corynebacterium sp., coagulase-negative staphylococci, Propionibacterium acnes, and Staphylococcus aureus, was seen in the group with acute maxillary sinusitis and also occasionally in the service group. When a sinus aspirate culture yielded a presumed sinus pathogen, the same pathogen was found in the nasal samples in 91% of the cases. The predictive value of a pathogen-positive nasal finding was highest (93.8%) for S. pyogenes, followed by 77.7% for H. influenzae and 68.7% for S. pneumoniae, and lowest (20%) for B. catarrhalis. 相似文献
9.
Pekka Oja Raija M. T. Laukkanen T. Katriina Kukkonen-Harjula Ilkka M. Vuori Matti E. Pasanen Seppo P. T. Niittymäki Tiina Solakivi 《European journal of applied physiology》1991,62(6):400-404
Summary Two experiments were carried out to compare the cardiorespiratory and metabolic effects of cross-country skiing and running training during two successive winters. Forty-year-old men were randomly assigned into skiing (n = 15 in study 1,n = 16 in study 2), running (n = 16 in study 1 andn = 16 in study 2) and control (n = 17 in study 1 andn = 16 in study 2) groups. Three subjects dropped out of the programme. The training lasted 9–10 weeks with 40-min exercise sessions three times each week. The training intensity was controlled at 75%–85% of the maximal oxygen consumption (VO2max) using portable heart rate metres and the mean heart rate was 156–157 beats·min–1 in the training groups. In the pooled data of the two studies the mean increase in theVO2max (in ml·min–1·kg–1) on a cycle ergometer was 17% for the skiing group, 13% for the running group and 2% for the control group. The increase inVO2max was highly significant in the combined exercise group compared to the control group but did not differ significantly between the skiing and running groups. The fasting serum concentrations of lipoproteins and insulin did not change significantly in any of the groups. These results suggested that training by cross-country skiing and running of the same duration and intensity at each session for 9–10 weeks improved equally the cardiorespiratory fitness of untrained middle-aged men. 相似文献
10.
H R Jousimies-Somer S Savolainen J S Ylikoski 《Journal of clinical microbiology》1988,26(10):1919-1925
Bacteriological findings in 339 sinus secretions obtained by puncture were investigated in 238 young adult patients with acute maxillary sinusitis. Aerobic and anaerobic cultures were performed immediately. A total of 76% of the secretions were positive. The most common pathogens isolated were Haemophilus influenzae (50%), Streptococcus pneumoniae (19%), Streptococcus pyogenes (5%), and Branhamella catarrhalis (2%). Coagulase-negative staphylococci and Staphylococcus aureus were isolated in 8 and 1% of the specimens, respectively. The staphylococci were almost invariably present in low numbers and, therefore, probably represented nasal contamination. Other aerobic species were found only occasionally. Anaerobes were isolated in 5% of the secretions. In one-half of these, a low concentration of Propionibacterium acnes was the sole anaerobe that was found, and it was usually mixed with a facultative organism (suggestive of contamination with nasal flora). Only 2% of the sinuses were considered to have true anaerobic infections (high concentrations of several species typical of anaerobic infection), indicating that anaerobes are not a significant cause of acute maxillary sinusitis in a young adult population. The high recovery of H. influenzae in this study indicates that aminopenicillins may be more appropriate choice than conventional penicillin in the antimicrobial therapy of acute maxillary sinusitis (only 2 of 168 H. influenzae strains produced beta-lactamase). 相似文献