全文获取类型
收费全文 | 1031139篇 |
免费 | 106288篇 |
国内免费 | 4185篇 |
专业分类
耳鼻咽喉 | 17853篇 |
儿科学 | 30309篇 |
妇产科学 | 27951篇 |
基础医学 | 132312篇 |
口腔科学 | 27910篇 |
临床医学 | 104110篇 |
内科学 | 214265篇 |
皮肤病学 | 24773篇 |
神经病学 | 86852篇 |
特种医学 | 42907篇 |
外国民族医学 | 171篇 |
外科学 | 179294篇 |
综合类 | 25302篇 |
现状与发展 | 74篇 |
一般理论 | 280篇 |
预防医学 | 76617篇 |
眼科学 | 24182篇 |
药学 | 67472篇 |
1篇 | |
中国医学 | 1614篇 |
肿瘤学 | 57363篇 |
出版年
2018年 | 14626篇 |
2017年 | 12988篇 |
2016年 | 14818篇 |
2015年 | 16389篇 |
2014年 | 26993篇 |
2013年 | 33317篇 |
2012年 | 28768篇 |
2011年 | 29783篇 |
2010年 | 24701篇 |
2009年 | 27551篇 |
2008年 | 28775篇 |
2007年 | 29078篇 |
2006年 | 31313篇 |
2005年 | 28398篇 |
2004年 | 27227篇 |
2003年 | 25379篇 |
2002年 | 24535篇 |
2001年 | 39944篇 |
2000年 | 39810篇 |
1999年 | 34536篇 |
1998年 | 13266篇 |
1997年 | 12387篇 |
1996年 | 12250篇 |
1995年 | 11578篇 |
1994年 | 10077篇 |
1993年 | 9203篇 |
1992年 | 28575篇 |
1991年 | 27947篇 |
1990年 | 27144篇 |
1989年 | 26354篇 |
1988年 | 24738篇 |
1987年 | 24285篇 |
1986年 | 23128篇 |
1985年 | 22343篇 |
1984年 | 17466篇 |
1983年 | 15005篇 |
1982年 | 9895篇 |
1981年 | 9119篇 |
1979年 | 17508篇 |
1978年 | 12927篇 |
1977年 | 11001篇 |
1976年 | 9976篇 |
1975年 | 10778篇 |
1974年 | 13186篇 |
1973年 | 12678篇 |
1972年 | 12116篇 |
1971年 | 11124篇 |
1970年 | 10656篇 |
1969年 | 10194篇 |
1968年 | 9121篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
S Prescott M A Hadi R A Elton A W Ritchie G C Foubister J C Gould T B Hargreave 《British journal of urology》1990,66(5):509-514
Two different regimens of cephalosporin antibiotic prophylaxis were compared with antiseptic lubricating jelly to try to prevent infection and complications in 196 men after prostatic surgery. Pre-operative urine was cultured and prostatic chips (170 cases) were also cultured to define the source of any infection. The use of antibiotics was associated with a reduced risk of postoperative bacteriuria. No serious complications occurred, although 1 patient in the antiseptic treated group developed rigors; 79 of 170 patients (46%) had positive prostatic chip cultures, of whom 74 had sterile pre-operative urine. There was no association between the result of chip culture and the presence of a pre-operative catheter. Culture positive patients had an increased risk of post-operative urine infection, although the same organism was found in the prostate and urine in only 36% of cases of post-operative bacteriuria and in 43 (54%) the organism cultured from the prostate was Staphylococcus albus. This study provides further evidence of the benefit of true prophylactic antibiotic therapy for transurethral prostatic surgery and the prostatic chip data suggest that some of the risk is due to pre-operative contamination of the prostate in the absence of per-operative urinary infection or catheterisation. 相似文献
992.
Transcutaneous oxygen measurements (TcpO2) have been shown to be an index of tissue perfusion and it has been suggested that the main haemodynamic variable influencing tissue perfusion is cardiac output, assuming that inspired oxygen remains constant. To investigate this hypothesis we studied 23 consecutive patients in order to identify if changes in cardiac output correlated with similar changes in TcpO2 measurements. No correlation was found to suggest that cardiac output was the main haemodynamic determinant of TcpO2 measurements. 相似文献
993.
There is little data to support the efficacy of prophylactic antibiotics in traumatology. In closed fractures three randomized controlled studies using a 1-3 day prophylaxis with Cephalosporins of the first or second generation or a Penicillinase-resistent Penicillin demonstrated a reduction of the infection rate. For the Cephalosporins of the second generation it was shown, that a single dose was less efficient than five repeated applications over 24 hours. In hip-fractures a prophylaxis with Cephalothin or Cefotiam reduced the frequency of infections when compared with controls. In open fractures a treatment over 10 days using Cephalothin or Isoxazolyl-Penicillin showed a significant drop of the infection rate. If however the fractures were not treated using the principles of rigid internal fixation and were covered with Dicloxacillin over 2 days only there was no significant improvement. A multicenter study finally indicates that a one day course of cefonicid sodium is not inferior to a prolonged course of antibiotics for prevention of early postoperative fracture-site infections. We conclude, that open and closed fractures can profit from antibiotic prophylaxis which starts immediately before surgery and is continued over 24 hours. We favour Isoxazolyl-Penicillin because of its efficacy against staphylococcus aureus and epidermidis which predominate in early infection. In established bone and soft tissue infections antibiotics are used when there is local spreading, sepsis, involvement of joints or when reinterventions in the infectious focus are necessary. In these cases bacteriological testing in the laboratory is essential for the selection of antibiotics. Local application of antibiotics in irrigation-drainage solutions can not be recommended. PMMA-chains serve as temporary spacers, but should be removed early before their extraction becomes difficult and resistant bacteria develop. When defects are closed with cancellous bone or soft tissues the use of Gentamycin-fleece or Taurolin-gels is recommended. 相似文献
994.
Serial peritoneal macrophage function studies in new and established continuous ambulatory peritoneal dialysis patients 总被引:1,自引:0,他引:1
Peritoneal macrophages (PM) perform first-line defense activity against peritonitis, the most important complication in continuous ambulatory peritoneal dialysis (CAPD) therapy. Our longitudinal study has compared the PM function in 20 uremic patients during periods free of peritonitis since they started CAPD therapy in January 1987. The results showed that at the initiation of CAPD, there was a higher bactericidal activity, phagocytosis index, H2O2 production and interleukin-1 (IL-1), gamma-interferon (IFN-gamma) and tumor necrosis factor (TNF) production ability and MHC expression. As time went on, these progressively decreased, and by 9 months after CAPD therapy had started they were significantly lower than at the beginning. During the 1.5-year follow-up period, there was a significantly increased peritonitis rate in the period 6 months after the beginning of CAPD than in the period before the 6th month (88.3 vs. 11.7% respectively; p less than 0.001). These results indicate that PM of new CAPD patients have a more active function than those of established patients. The established patients had a greater risk of peritonitis. A comparison of the immunological profiles of PM from patients who had a peritonitis history shows that phagocytosis index, bactericidal activity and IL-1 and TNF production of PM were significantly decreased during the period free of peritonitis. This result suggests that these parameters may serve as an indicator in developing peritonitis. 相似文献
995.
Scoliosis in pediatric spinal cord-injured patients 总被引:1,自引:0,他引:1
W W Dearolf R R Betz L C Vogel J Levin M Clancy H H Steel 《Journal of pediatric orthopedics》1990,10(2):214-218
One hundred thirty children who sustained spinal cord injuries between birth and age 21 years were reviewed to determine the progression rate of paralytic scoliosis and the effects of bracing and surgery. Patients were divided into two groups: those injured before and those injured after the adolescent growth spurt. Scoliosis developed in 97 and 52%, respectively. Bracing was effective in delaying progression in the preadolescent group. The progressive paralytic spinal deformity did not appear to be related to the level of injury. The older patient is at much less risk for paralytic scoliosis, but still requires routine examination. 相似文献
996.
Acute viral myocarditis A death associated with anaesthesia 总被引:1,自引:0,他引:1
The death of a 35-year-old woman in the immediate postoperative period as a result of undiagnosed acute viral myocarditis is described. The presentation, diagnosis and course of the disease is discussed. It is recommended that wider use to be made of routine electrocardiographs as a screening test. 相似文献
997.
998.
Development of grating acuity in infants with regressed stage 3 retinopathy of prematurity 总被引:4,自引:0,他引:4
The acuity card procedure was used to measure grating acuity in 17 infants with regressed Stage 3 retinopathy of prematurity (ROP) who had no lasting anatomic changes in the retina or optic nerve. Results were compared with those of 28 healthy preterm infants and 28 infants matched by birth weight and gestational age who did not have Stage 3 ROP. Infants in the ROP group showed delayed grating acuity development until 2 years of age. This difference among groups was significant at the 3-5- and 10-12-month test ages but not at the 0-1-, 8-9-, and 16-18-month test ages. Post hoc analyses indicated that the delay in acuity development shown by the ROP group was due to the poor acuity scores of the infants in that group who had central nervous system abnormalities of periventricular leukomalacia or severe (Grade III or IV) intraventricular hemorrhage. When the data of these infants were removed from the analysis, the ROP group showed acuity development similar to that of both the healthy preterm group and the group of infants with matched birth weights and gestational ages who did not have Stage 3 ROP. 相似文献
999.
A B Fulton J Dodge J L Schremser A Armstrong F Lanier W W Dawson T P Williams 《Current eye research》1990,9(12):1211-1216
The content of rhodopsin in the eyes of 15 donors (30 eyes) was determined. Both retinal and pigment epithelial fractions were collected from each globe, extracted using 1% CTAB, and the rhodopsin difference spectrum of each fraction was obtained separately. The total amount of rhodopsin, obtained by summing the amounts recovered from the retinal and PE fractions, ranged from 2.00 to 11.94 (median: 6.40) nmoles/eye. Previously reported mean values of about 3.5 to 4.0 nmoles per retina have been obtained using a variety of methods. The present higher values, perhaps largely dependent on procedural details described herein, appear plausible given the known concentrations of rhodopsin in rod outer segments, rod outer segment volumes, and number of rods in the human retina. 相似文献
1000.
Relaxing retinotomies. Analysis of anatomic and visual results 总被引:6,自引:0,他引:6
The authors analyzed 100 consecutive eyes undergoing relaxing retinotomies to determine the anatomic and visual results associated with the use of this procedure. With a minimum follow-up of 6 months, 58 eyes were completely attached, 8 were partially attached (macula on), and 34 were detached. Thirty-four percent of all eyes and 50% of attached eyes obtained a visual acuity of 5/200 or greater at 6 months. At last examination, 29% of all eyes and 43% of attached eyes had a visual acuity of at least 5/200. Eyes that had circumferential relaxing retinotomies involving the entire temporal quadrant generally had lower visual acuities when compared with eyes that had relaxing retinotomies sparing the entire temporal quadrant. The use of a radial relaxing retinotomy also was associated with lower final visual acuity. The length of the relaxing retinotomy or the placement of the relaxing retinotomy either anterior or posterior to the encircling scleral buckle did not appear to influence the anatomic or visual results. Hypotony (intraocular pressure less than 5 mmHg) was seen in 43% of reattached eyes. 相似文献