全文获取类型
收费全文 | 6241篇 |
免费 | 497篇 |
国内免费 | 23篇 |
专业分类
耳鼻咽喉 | 46篇 |
儿科学 | 234篇 |
妇产科学 | 72篇 |
基础医学 | 762篇 |
口腔科学 | 184篇 |
临床医学 | 889篇 |
内科学 | 1341篇 |
皮肤病学 | 63篇 |
神经病学 | 538篇 |
特种医学 | 338篇 |
外科学 | 797篇 |
综合类 | 170篇 |
一般理论 | 2篇 |
预防医学 | 475篇 |
眼科学 | 60篇 |
药学 | 329篇 |
1篇 | |
中国医学 | 4篇 |
肿瘤学 | 456篇 |
出版年
2022年 | 36篇 |
2021年 | 95篇 |
2020年 | 61篇 |
2019年 | 99篇 |
2018年 | 97篇 |
2017年 | 88篇 |
2016年 | 104篇 |
2015年 | 112篇 |
2014年 | 135篇 |
2013年 | 184篇 |
2012年 | 287篇 |
2011年 | 287篇 |
2010年 | 190篇 |
2009年 | 161篇 |
2008年 | 261篇 |
2007年 | 276篇 |
2006年 | 245篇 |
2005年 | 226篇 |
2004年 | 235篇 |
2003年 | 228篇 |
2002年 | 200篇 |
2001年 | 191篇 |
2000年 | 178篇 |
1999年 | 193篇 |
1998年 | 151篇 |
1997年 | 148篇 |
1996年 | 132篇 |
1995年 | 113篇 |
1994年 | 91篇 |
1993年 | 81篇 |
1992年 | 125篇 |
1991年 | 115篇 |
1990年 | 123篇 |
1989年 | 162篇 |
1988年 | 134篇 |
1987年 | 125篇 |
1986年 | 97篇 |
1985年 | 131篇 |
1984年 | 94篇 |
1983年 | 77篇 |
1982年 | 60篇 |
1981年 | 58篇 |
1980年 | 41篇 |
1979年 | 59篇 |
1978年 | 47篇 |
1977年 | 35篇 |
1975年 | 30篇 |
1973年 | 49篇 |
1972年 | 31篇 |
1969年 | 35篇 |
排序方式: 共有6761条查询结果,搜索用时 15 毫秒
91.
Ventral wall hernias are common; despite this, there are no guidelines on the best surgical management. The aim of this study
was to examine the types of repair in use for abdominal wall hernias in the West of Scotland over a 3-month period. Data were
gathered on 120 patients. There were 60 incisional, 32 umbilical, and 28 epigastric hernias. The main indication for repair
was pain (78%), while 12 patients (10%), presented acutely with incarceration or strangulation. The most common method of
repair was sutured (55%), followed by mesh (29%) and Mayo repair (16%). There was no correlation between use of mesh and hernia
size or whether repair was for a recurrent hernia. Surgical practice varies widely in the repair of ventral wall hernias.
Clinical trials are required to establish the best method of repair for this common condition.
Electronic Publication 相似文献
92.
Zuckerman JD Gallagher MA Cuomo F Rokito A 《Journal of shoulder and elbow surgery / American Shoulder and Elbow Surgeons ... [et al.]》2003,12(2):105-109
Proprioceptive ability was prospectively evaluated in patients with recurrent traumatic anterior instability who subsequently underwent anterior shoulder repair. Thirty consecutive patients were evaluated for passive position sense and detection of motion with the shoulder in flexion, abduction, and external rotation 1 week before surgery. They were then retested at 6 and 12 months postoperatively. A significant deficit in proprioception was found when the unstable side was compared with the uninvolved side before surgery. Six months after surgical repair, position sense showed an improvement of approximately 50% but was still found to be significantly different on the involved side; detection of motion was no longer significantly different from the uninvolved shoulder. One year after open anterior shoulder repair, both position sense and detection of motion were equivalent to those of the uninvolved shoulder. 相似文献
93.
Psychomotor skills assessment in practicing surgeons experienced in performing advanced laparoscopic procedures 总被引:6,自引:0,他引:6
Gallagher AG Smith CD Bowers SP Seymour NE Pearson A McNatt S Hananel D Satava RM 《Journal of the American College of Surgeons》2003,197(3):479-488
BACKGROUND: Minimally invasive surgery (MIS) has introduced a new and unique set of psychomotor skills for a surgeon to acquire and master. Although assessment technologies have been proposed, precise and objective psychomotor skills assessment of surgeons performing laparoscopic procedures has not been detailed. STUDY DESIGN: Two hundred ten surgeons attending the 2001 annual meeting of the American College of Surgeons in New Orleans who reported having completed more than 50 laparoscopic procedures participated. Subjects were required to complete one box-trainer laparoscopic cutting task and a similar virtual reality task. These tasks were specifically designed to test only psychomotor and not cognitive skills. Both tasks were completed twice. Performance of tasks was assessed and analyzed. Demographic and laparoscopic experience data were also collected. RESULTS: Complete data were available on 195 surgeons. In this group, surgeons performed the box-trainer task better with their dominant hand (p < 0.0001) and there was a strong and statistically significant correlation between trials (r = 0.47 - 0.64, p < 0.0001). After transforming raw data to z-scores (mean = 0 and SD = 1) it was shown that between 2% and 12% of surgeons performed more than two standard deviations from the mean. Some surgeons' performance was 20 standard deviations from the mean. Minimally Invasive Surgical Trainer Virtual Reality metrics demonstrated high measurement consistency as assessed by coefficient alpha (alpha = 0.849). CONCLUSIONS: Objective assessment of laparoscopic psychomotor skills is now possible. Surgeons who had performed more than 50 laparoscopic procedures showed considerable variability in their performance on a simple laparoscopic and virtual reality task. Approximately 10% of surgeons tested performed the task significantly worse than the group's average performance. Studies such as this may form the methodology for establishing criteria levels and performance objectives in objective assessment of the technical skills component of determining surgical competence. 相似文献
94.
Cor P van der Hart Michel PJ van den Bekerom Thomas W Patt 《Journal of orthopaedic surgery and research》2008,3(1):24
Objective
The objective of this study was to evaluate the incidence of radiographic osteoarthritis in the operated knee in comparison with the contralateral knee ten years after a bone-tendon bone patellar autograft ACL-reconstruction and to evaluate to which level patients regain activity ten years after reconstruction. 相似文献95.
Jonathan D. Dodd Sinead C. Barry Rupert B.M. Barry Tom. J. Cawood Malachi J. McKenna Charles G. Gallagher 《Journal of clinical densitometry》2008,11(4):746-542
The aim of this study was to evaluate the association between bone mineral density (BMD) and objective maximal exercise measurements in adults with cystic fibrosis (CF). Twenty-five CF patients (19 males, 6 females, mean age 25.5 yr, range: 17–52) underwent BMD assessment and maximal-cycle ergometer exercise testing. We examined the relationship between gas exchange (% peak-predicted O2 uptake, CO2 output, O2 saturation), exercise performance (maximum power, exercise duration), and respiratory mechanics (tidal volume, rate) with lumbar spine and total proximal femur BMD. The strongest clinical correlate with BMD was forced expiratory volume at 1 s (lumbar spine Z-score, r = 0.36; total proximal femur Z-score, r = 0.68, p < 0.01). The strongest exercise correlate was % peak-predicted O2 uptake (lumbar spine Z-score, r = 0.44, p < 0.01; total proximal femur Z-score, r = 0.59, p < 0.01). There was a closer association between exercise parameters and total proximal femur BMD (r = 0.43–0.60) than with lumbar spine BMD (r = 0.04–0.45). Multiple regression analysis revealed VO2 to be the strongest independent predictor of BMD (R2 = 0.86, p < 0.001) followed by petCO2 and body mass index (R2 = 0.7 and 0.5, respectively, p < 0.01). Exercise appears to influence total proximal femur BMD more than lumbar spine BMD in CF. Exercise rehabilitation programs focusing on peripheral strength training may benefit those CF patients with low total proximal femur BMD. 相似文献
96.
Neville CE Robson PJ Murray LJ Strain JJ Twisk J Gallagher AM McGuinness M Cran GW Ralston SH Boreham CA 《Calcified tissue international》2002,70(2):89-98
Optimizing peak bone mass in early life may reduce osteoporosis risk in later life. Such optimization may be partly dependent upon diet. In the present study, nutrient intakes and selected lifestyle parameters were assessed in adolescent subjects (238 males, 205 females; aged 15 y) and again, in the same subjects, on one occasion in young adulthood (aged between 20 and 25 y). The extent of the relationships between these parameters and bone mineral density (BMD), dual energy X-ray absorptiometry (DXA), lumbar spine (L2-L4), and femoral neck measured concurrently with diet in young adulthood only, was assessed. Adjusted linear regression models were constructed. Variables included a measure of pubertal status (at age 15 y), age (at young adulthood), height, weight, physical activity, smoking, and mean daily intakes of energy, calcium, protein, vitamin D, phosphorus, total fat, and alcohol. In both sexes, body weight at adolescence and young adulthood was the only factor consistently positively associated with BMD at both measurement sites. Effects of nutrient intake on BMD were inconsistent. Vitamin D and calcium intakes reported by female adolescents showed significant positive relationships with BMD measured in young adulthood (vitamin D measured at the lumbar spine; calcium measured at the femoral neck). The positive relationship between vitamin D and BMD remained significant at young adulthood, but at the femoral neck rather than at the lumbar spine. Also in females, intakes of phosphorus and the calcium:phosphorus ratio (Ca:P) at adolescence were strongly negatively related to femoral neck BMD measured at young adulthood. In males, however, Ca:P reported at young adulthood had a significant positive relationship with lumbar spine BMD, whereas Ca:protein was negatively associated with BMD at the lumbar spine. Intakes of Ca reported by adolescent males also had a strong negative effect on lumbar spine BMD measured at young adulthood. 相似文献
97.
Perkovic V Ninomiya T Arima H Gallagher M Jardine M Cass A Neal B Macmahon S Chalmers J 《Journal of the American Society of Nephrology : JASN》2007,18(10):2766-2772
Chronic kidney disease (CKD) is associated with a high risk of cardiovascular disease, but evidence regarding the effectiveness of interventions to reduce that risk is lacking. The Perindopril Protection against Recurrent Stroke Study (PROGRESS) study enrolled 6105 participants with cerebrovascular disease and randomly allocated them to perindopril-based blood pressure-lowering therapy or placebo. Individuals with CKD were at approximately 1.5-fold greater risk of major vascular events, stroke, and coronary heart disease, and were more than twice as likely to die (all P< or =0.002). Perindopril-based treatment reduced the risk of major vascular events by 30% and stroke by 35% among subjects with CKD, and the absolute effects of treatment were 1.7-fold greater for those with CKD than for those without. Considering patients with CKD and a history of cerebrovascular disease, perindopril prevented one stroke or other cardiovascular event among every 11 patients treated over five years. In conclusion, kidney function should be considered when determining the need for blood pressure lowering therapy in patients with cerebrovascular disease. 相似文献
98.
S. A. Shah M. S. Cattral I. D. McGilvray L. D. Adcock G. Gallagher R. Smith L. B. Lilly N. Girgrah P. D. Greig G. A. Levy D. R. Grant 《American journal of transplantation》2007,7(1):142-150
Many centers are reluctant to use older donors (>44 years) for adult right-lobe living donor liver transplantation (RLDLT) due to concerns about possible increased morbidity in donors and poorer outcomes in recipients. Since 2000, 130 adult RLDLTs have been performed at our institution. Recipients were divided into those who received a right lobe graft from a donor ≤age 44 (n = 89, 68%; median age 30) and those who received a liver graft from a donor age >44 (n = 41, 32%; mean age 52). The two donor and recipient populations had similar demographic and operative profiles. With a median follow-up of 29 months, the severity and number of complications in older donors were similar to those in younger donors. No living donor died. Older donor allografts had initial allograft dysfunction compared to younger donors. Complication rates were similar among recipients in both groups but there was a higher bile duct stricture rate with older donor grafts (27% vs. 12%; p = 0.04). One-year recipient graft survival was 86% for older donors and 85% for younger donors (p = 0.95). Early experience with the use of selected older adults (>44 years) for RLDLT is encouraging, but may be associated with a higher rate of biliary complications in the recipient. 相似文献
99.
Nucleotides such as adenosine triphosphate (ATP) and uridine triphosphate (UTP) exist in the extracellular environment where they are agonists at P2 receptors. Both P2Y G-protein-coupled receptors and P2X ligand-gated ion channels are expressed by osteoblasts and osteoclasts, reflected in the diverse nucleotide-induced effects reported to occur in bone. Previous reports have implicated ATP as a proresorptive agent; however, these studies were unable to determine whether ATP mediated its actions directly on osteoclasts, or indirectly via osteoblasts. The development of techniques to generate human osteoclasts in vitro has allowed us to further investigate the intriguing role of extracellular nucleotides with regard to osteoclast activity. This study reports that nearly all P2-receptor-subtype mRNAs were expressed throughout human osteoclast development, and provides evidence for functional P2 receptor expression by these cells. In cultures of human osteoclasts alone, neither ATP nor UTP affected the quantity of resorption by these cells; however, in cocultures of osteoblast-like UMR-106 cells and human osteoclasts, ATP, but not UTP, greatly enhanced resorption, indicating a role for osteoblasts in mediating the proresorptive effects of ATP. Furthermore, ATP, but not UTP, elevated receptor activator of nuclear factor-kappaB ligand (RANKL) mRNA and protein expression by UMR-106 cells. These data are consistent with observations that UMR-106 cells predominantly express P2Y(1) with low expression of P2Y(2), thereby explaining the response to ATP and not UTP, and further substantiating the involvement of osteoblasts in ATP-induced effects on osteoclasts. These results significantly advance our understanding of the role of P2 receptors in bone, and indicate that local-acting ATP may play a pivotal role in osteoclast activation at bone-resorbing sites by inducing elevated expression of RANKL. 相似文献
100.