全文获取类型
收费全文 | 7970篇 |
免费 | 754篇 |
国内免费 | 15篇 |
专业分类
耳鼻咽喉 | 76篇 |
儿科学 | 323篇 |
妇产科学 | 128篇 |
基础医学 | 1268篇 |
口腔科学 | 155篇 |
临床医学 | 914篇 |
内科学 | 1517篇 |
皮肤病学 | 66篇 |
神经病学 | 647篇 |
特种医学 | 426篇 |
外科学 | 1023篇 |
综合类 | 174篇 |
一般理论 | 4篇 |
预防医学 | 799篇 |
眼科学 | 126篇 |
药学 | 491篇 |
中国医学 | 20篇 |
肿瘤学 | 582篇 |
出版年
2021年 | 130篇 |
2020年 | 90篇 |
2019年 | 114篇 |
2018年 | 162篇 |
2017年 | 83篇 |
2016年 | 139篇 |
2015年 | 135篇 |
2014年 | 167篇 |
2013年 | 261篇 |
2012年 | 349篇 |
2011年 | 385篇 |
2010年 | 204篇 |
2009年 | 200篇 |
2008年 | 277篇 |
2007年 | 365篇 |
2006年 | 366篇 |
2005年 | 301篇 |
2004年 | 287篇 |
2003年 | 263篇 |
2002年 | 274篇 |
2001年 | 257篇 |
2000年 | 261篇 |
1999年 | 181篇 |
1998年 | 121篇 |
1997年 | 119篇 |
1996年 | 108篇 |
1995年 | 89篇 |
1994年 | 97篇 |
1993年 | 94篇 |
1992年 | 162篇 |
1991年 | 163篇 |
1990年 | 150篇 |
1989年 | 177篇 |
1988年 | 167篇 |
1987年 | 209篇 |
1986年 | 161篇 |
1985年 | 160篇 |
1984年 | 130篇 |
1983年 | 109篇 |
1982年 | 63篇 |
1981年 | 63篇 |
1980年 | 65篇 |
1979年 | 74篇 |
1978年 | 78篇 |
1977年 | 66篇 |
1976年 | 66篇 |
1974年 | 72篇 |
1973年 | 80篇 |
1972年 | 65篇 |
1971年 | 65篇 |
排序方式: 共有8739条查询结果,搜索用时 31 毫秒
11.
R C Flanigan M F Ellison K M Butler L G Gomella J W McRoberts 《The Journal of urology》1986,136(1):35-37
There were 40 consecutive patients with recurrent or multiple superficial stage Ta or T1 transitional cell cancer assigned randomly to receive prophylactic thiotepa or mitomycin C intravesical chemotherapy. Patients received 8 weekly instillations followed by 22 monthly treatments of either 60 mg. thiotepa or 40 mg. mitomycin C. Of 25 patients randomized to receive mitomycin C 4 had recurrence in a total of 337 patient-months (1.19 per 100 patient-months), while disease recurred in 1 of 15 patients randomized to receive thiotepa who were followed for a total of 220 patient-months (0.45 per 100 patient-months). No significant difference in recurrence rate was noted for either drug group (p equals 0.18). Toxicity requiring cessation of therapy was observed in 7 patients (28 per cent) on mitomycin C and none on thiotepa. 相似文献
12.
Pattern of postprandial carbohydrate metabolism and effects of portal and peripheral insulin delivery 总被引:4,自引:0,他引:4
E J Kryshak P C Butler C Marsh A Miller D Barr K Polonsky J D Perkins R A Rizza 《Diabetes》1990,39(2):142-148
The importance of portal insulin delivery in the regulation of postprandial carbohydrate metabolism is uncertain. To address this question, three groups of dogs were studied: one group in which pancreatic venous drainage was transected and reanastomosed (portal insulin delivery), one in which the pancreatic drainage was transected and anastomosed to the inferior vena cava (peripheral insulin delivery), and one that received only a sham operation. Plasma insulin was greater (P less than 0.05) during peripheral insulin delivery than in either the portal or sham groups, respectively, before and after meal ingestion. On the other hand, C-peptide concentrations did not differ between groups, resulting in a higher (P less than 0.001) insulin to C-peptide ratio in the peripheral group. This indicated that the hyperinsulinemia in the peripheral group was due to decreased insulin clearance rather than increased insulin secretion. Isotopically determined splanchnic uptake of ingested glucose, postprandial suppression of hepatic glucose release, incorporation of CO2 into glucose (a qualitative measure of gluconeogenesis), and total-body glucose uptake were virtually identical in all groups. Similarly, plasma lipid, beta-hydroxybutyrate, and lactate concentrations did not differ between groups. Our data indicate that, despite differences in systemic insulin concentration, portal and peripheral insulin delivery comparably regulate hepatic and extrahepatic carbohydrate metabolism after meal ingestion. 相似文献
13.
Minor Psychiatric Morbidity, Its Prevalence and Outcome in a Cohort of Civil Servants A Seven-year Follow-up Study 总被引:1,自引:0,他引:1
Jenkins R.; Harvey S.; Butler T.; Lloyd Thomas R. 《Occupational medicine (Oxford, England)》1996,46(3):209-215
During the years 1979–1986, a cohort of direct entrantexecutive officers in the Civil Service were followed up toexamine the prevalence and outcome of minor psychiatric morbidityin an occupational setting. All studies using epidemiologicalstandardized research methods agree, that prevalence rates arehigh in occupational settings. As in primary care settings,half of the illness episodes followed a chronic course, whichemphasizes the need for early detection and prompt managementof these conditions, and for evaluative studies of interventionstrategies. 相似文献
14.
Dr. Thomas C. Hardin Pharm.D. FCCP Dr. Steven C. Butler M.D. Dr. Sabine Ross M.D. Dr. John H. Wakeford Pharm.D. Dr. James H. Jorgensen Ph.D. 《Pharmacotherapy》1994,14(2):147-152
Study Objectives . To evaluate the pharmacodynamic antibacterial activity of ticarcillin-clavulanic acid (T-C) and ampicillin-sulbactam (A-S) combinations against reference bacterial strains in patients with end-stage renal disease maintained on long-term hemodialysis. Design . Randomized, crossover, controlled study. Setting . National Institutes of Health-funded general clinical research unit in a Veterans Administration Medical Center. Patients . Nine adult men with end-stage renal disease maintained on long-term hemodialysis. Two subjects did not complete the study due to problems of vascular access, and another withdrew for personal reasons. Interventions . On a nondialysis day, each subject was randomly administered either T-C 3.1 g or A-S 3 g as a slow intravenous infusion over 30 minutes. Serial blood samples were collected for measurement of antibiotic serum concentrations and determination of serum bactericidal titers. Following a washout period, the study was repeated with the alternative antibiotic combination. Measurements and Main Results . The mean observed apparent β-half-life of clavulanic acid was substantially shorter than that for the other three drugs. The bactericidal activity of both A-S and T-C against non-β-lactamase-producing (Nβ-LP) strains of S. aureus and E. coli was consistently high, as indicated by geometric mean SBTs of at least 1:5 at 24 hours. Against β-lactamase-producing (β-LP) S. aureus, the geometric mean SBTs for A-S were at least 1:25 throughout the study period, while the geometric mean SBTs for T-C decreased over 24 hours from 1:29 to 1:6. Against β-LP E. coli, the bactericidal activities for both A-S and T-C were poor, with geometric mean peak SBTs of only 1:6 and 1:3, respectively. The geometric mean SBT for T-C against this E. coli strain had declined to 1:1 at 6 hrs. Conclusion . Increasing the dosing interval for T-C in patients with end-stage renal disease may lead to periods of insufficient clavulanic acid to protect ticarcillin from β-lactamase degradation. 相似文献
15.
Paediatric dacryocystorhinostomy 总被引:1,自引:0,他引:1
KN Hakin FRCS FRCOphth TJ Sullivan FRACO FRACS A Sharma FCOphth † RAN Welham FRCS FCOphth † 《Clinical & experimental ophthalmology》1994,22(4):231-235
Of 258 cases of dacryocystorhinostomy performed on children in the period September 1981 to September 1991, 130 were for simple, unresolved congenital nasolacrimal duct obstruction. Other indications for surgery included punctal agenesis, lacrimal fistula, post-traumatic and post-inflammatory canalicular obstruction. Of 177 children without canalicular pathology, 171 (96%) were relieved of symptoms with one operation, without canalicular intubation. Of 81 cases with canalicular disease, 55 of 70 (79%) who underwent DCR plus canalicular intubation, and 10 of 11 who underwent DCR plus Lester-Jones tube, were substantially improved with one operation. No child required peroperative or postoperative blood transfusion. Dacryocystorhinostomy in childhood, in experienced surgical hands, is a safe procedure, achieving relief of symptoms in most cases, particularly in the absence of canalicular disease. 相似文献
16.
17.
D Anderson S Goyle B J Phillips A Tee L Beech W H Butler 《Occupational and environmental medicine》1988,45(4):269-274
Since the Bhopal disaster, in which the causal agent was methyl isocyanate (MIC), exposed people have complained of various disorders including neuromuscular dysfunction. In an attempt to gain some information about the response of muscle tissue to MIC its effects were investigated in cells in culture isolated from muscle of 2 day old rats. After treatment with a range of MIC concentrations (0.025-0.5 microliter/5 ml culture) the total number of nuclei of the two main cell types (fibroblasts and myoblasts) and the number of nuclei in muscle fibres (myotubes) were recorded. At lower doses which had little effect on the total number of nuclei, the formation of muscle fibres--that is, fusion of muscle cells--was prevented as the proportion of nuclei in myotubes was decreased. At higher doses both cell types were killed. This would suggest either an effect on muscle differentiation or a selective toxicity towards myoblasts. The observations were supported by light and electron microscopy. 相似文献
18.
19.
OBJECTIVE: This study investigated non-adherence to antiepileptic drug treatment amongst patients with epilepsy in secondary care. The associations between adherence and seizure control, perceptions of illness and medication, anxiety and depression were also examined. METHODS: A cross-sectional study of fifty-four patients with epilepsy were recruited from a hospital epilepsy clinic. RESULTS: Fifty-nine percent were estimated to be non-adherent to medication. There was a negative correlation between adherence and frequency of seizures. Patients with poorly controlled epilepsy were more anxious, and expected a longer duration of their epilepsy. CONCLUSION: Assessment of adherence should be a routine part of management of epilepsy. Further recognition and support should be given to patients who have poor seizure control since they are more likely to be more anxious and have unhelpful illness and treatment beliefs. 相似文献
20.