全文获取类型
收费全文 | 71978篇 |
免费 | 4893篇 |
国内免费 | 202篇 |
专业分类
耳鼻咽喉 | 532篇 |
儿科学 | 2110篇 |
妇产科学 | 1169篇 |
基础医学 | 9882篇 |
口腔科学 | 1518篇 |
临床医学 | 7552篇 |
内科学 | 15245篇 |
皮肤病学 | 981篇 |
神经病学 | 6840篇 |
特种医学 | 2250篇 |
外国民族医学 | 1篇 |
外科学 | 10079篇 |
综合类 | 880篇 |
一般理论 | 72篇 |
预防医学 | 6408篇 |
眼科学 | 1749篇 |
药学 | 4918篇 |
1篇 | |
中国医学 | 80篇 |
肿瘤学 | 4806篇 |
出版年
2023年 | 377篇 |
2022年 | 522篇 |
2021年 | 1403篇 |
2020年 | 845篇 |
2019年 | 1368篇 |
2018年 | 1664篇 |
2017年 | 1239篇 |
2016年 | 1360篇 |
2015年 | 1591篇 |
2014年 | 2371篇 |
2013年 | 3223篇 |
2012年 | 5253篇 |
2011年 | 5372篇 |
2010年 | 3010篇 |
2009年 | 2669篇 |
2008年 | 4890篇 |
2007年 | 5350篇 |
2006年 | 5248篇 |
2005年 | 4984篇 |
2004年 | 4776篇 |
2003年 | 4317篇 |
2002年 | 4214篇 |
2001年 | 578篇 |
2000年 | 407篇 |
1999年 | 644篇 |
1998年 | 901篇 |
1997年 | 755篇 |
1996年 | 642篇 |
1995年 | 607篇 |
1994年 | 493篇 |
1993年 | 466篇 |
1992年 | 351篇 |
1991年 | 306篇 |
1990年 | 257篇 |
1989年 | 250篇 |
1988年 | 263篇 |
1987年 | 215篇 |
1986年 | 234篇 |
1985年 | 245篇 |
1984年 | 309篇 |
1983年 | 326篇 |
1982年 | 384篇 |
1981年 | 369篇 |
1980年 | 343篇 |
1979年 | 200篇 |
1978年 | 242篇 |
1977年 | 193篇 |
1976年 | 136篇 |
1975年 | 106篇 |
1974年 | 110篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Anand Dayama Nikolaos Tsilimparis Stephen Kolakowski Nathaniel M. Matolo Misty D. Humphries 《Journal of vascular surgery》2019,69(1):156-163.e1
Background
Chronic limb-threatening ischemia (CLTI), defined as ischemic rest pain or tissue loss secondary to arterial insufficiency, is caused by multilevel arterial disease with frequent, severe infrageniculate disease. The rise in CLTI is in part the result of increasing worldwide prevalence of diabetes, renal insufficiency, and advanced aging of the population. The aim of this study was to compare a bypass-first with an endovascular-first revascularization strategy in patients with CLTI due to infrageniculate arterial disease.Methods
We reviewed the American College of Surgeons National Surgical Quality Improvement Program targeted lower extremity revascularization database from 2012 to 2015 to identify patients with CLTI and isolated infrageniculate arterial disease who underwent primary infrageniculate bypass or endovascular intervention. We excluded patients with a history of ipsilateral revascularization and proximal interventions. The end points were major adverse limb event (MALE), major adverse cardiovascular event (MACE), amputation at 30 days, reintervention, patency, and mortality. Multivariable logistic regression was used to determine the association of a bypass-first or an endovascular-first intervention with outcomes.Results
There were 1355 CLTI patients undergoing first-time revascularization to the infrageniculate arteries (821 endovascular-first revascularizations and 534 bypass-first revascularizations) identified. There was no significant difference in adjusted rate of 30-day MALE in the bypass-first vs endovascular-first revascularization cohort (9% vs 11.2%; odds ratio [OR], 0.73; 95% confidence interval [CI], 0.50-1.08). However, the incidence of transtibial or proximal amputation was lower in the bypass-first cohort (4.3% vs 7.4%; OR, 0.60; CI, 0.36-0.98). Patients with bypass-first revascularization had higher wound complication rates (9.7% vs 3.7%; OR, 2.75; CI, 1.71-4.42) compared with patients in the endovascular-first cohort. Compared with the endovascular-first cohort, the incidence of 30-day MACE was significantly higher in bypass-first patients (6.9% vs 2.6%; adjusted OR, 3.88; CI, 2.18-6.88), and 30-day mortality rates were 3.23% vs 1.8% (adjusted OR, 2.77; CI, 1.26-6.11). There was no difference in 30-day untreated loss of patency, reintervention of treated arterial segment, readmissions, and reoperations between the two cohorts. In subgroup analysis after exclusion of dialysis patients, there was also no significant difference in MALE or amputation between the bypass-first and endovascular-first cohorts.Conclusions
CLTI patients with isolated infrageniculate arterial disease treated by a bypass-first approach have a significantly lower 30-day amputation. However, this benefit was not observed when dialysis patients were excluded. The bypass-first cohort had a higher incidence of MACE compared with an endovascular-first strategy. These results reaffirm the need for randomized controlled trials, such as the Bypass versus Angioplasty in Severe Ischaemia of the Leg (BASIL-2) trial and Best Endovascular vs Best Surgical Therapy in Patients with Critical Limb Ischemia (BEST-CLI), to provide level 1 evidence for the role of endovascular-first vs bypass-first revascularization strategies in the treatment of this population of challenging patients. 相似文献2.
OBJECTIVE: This study was conducted to compare an otolaryngologist's experience with a cohort of epilepsy patients implanted with a vagal nerve stimulator (VNS) to previously published data. METHODS: Demographics, preoperative seizure frequency, medications, and complications were retrospectively collected from patients implanted by the senior author. Postoperative medications and seizure frequency were obtained from referring neurologists. RESULTS: Seventeen patients were implanted over a 24-month period. Average age was 28.3 years. Patients presented with petit mal (n = 3), tonic-clonic (n = 6), complex partial (n = 5), and grand mal (n = 8) seizures. Mean follow-up postimplantation was 13.5 months. Most patients had at least a 50% reduction of seizure frequency, with 3 patients being seizure free. There were no postoperative infections. One patient had left vocal cord immobility. The most common side effect was voice disturbance during device activation. CONCLUSION: Otolaryngologists are well equipped to perform VNS implantation and to diagnose and treat possible laryngeal side effects. EBM rating: C-4. 相似文献
3.
4.
Elaina F. George Arnold Komisar Stephen C. Scharf Adrienne Ferracci Stanley Blaugrund 《The Laryngoscope》1998,108(5):627-629
A retrospective chart review of 43 patients who underwent technetium 99m (Tc-99m) sestamibi scans from June 1995 to January 1997 was performed. Only those who underwent subsequent parathyroid exploration with excision were included in the study. Twenty subjects (13 women and seven men) were included in the study. Ages ranged from 21 to 84 years (mean, 58 years). All patients had laboratory values and clinical findings consistent with primary hyperparathyroidism. Two patients had preoperative magnetic resonance imaging (MRI) scans (one patient with recurrent disease), and one had a preoperative computed tomography (CT) scan. The remaining patients had the sestamibi scan as the only preoperative localization study. There were 18 pathologic diagnoses of parathyroid adenoma and two of parathyroid hyperplasia. Sestamibi failed to correctly identify the location of the parathyroid lesion in two cases. In 18 cases the preoperative sestamibi scan correctly localized the lesion, a predictive value of 90%. We conclude that the Tc-99m sestamibi scan is an accurate preoperative tool that can be used as a single modality to localize parathyroid adenomas. 相似文献
5.
6.
7.
Hung-Tao Hsu Stephen J. Ryan 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1986,224(1):1-6
In one eye each of four cynomolgus monkeys, an 8-mm penetrating injury was made through the equator; there was retinal perforation with vitreous loss. None of the four eyes with this injury developed posterior vitreous detachment or retinal detachment during a follow-up period of 8 months to 1 year.Another group of 26 monkeys had the same injury but also had 0.5 ml autologous whole blood injected into the vitreous at the time of injury. The eyes were examined weekly and enucleated at scheduled intervals from 1 day to 52 weeks post-injury. Posterior vitreous detachment occurred at the earliest at 2 weeks post-injury, and was ultimately present in 91% of the eyes. Vitreous detachment can occur either as a separation at the level of the internal limiting membrane or as a cleavage within the cortical vitreous. Retinal detachment occurred at the earliest at 8 weeks post-injury, and eventually was present in 50% of the eyes. The retinal detachment was tractional; no retinal breaks were detected in any of the eyes.This study was supported by grants EY02061 and EY03040 from the National Institutes of HealthPresented at the 1984 meeting of the Club Jules Gonin in Lausanne, Switzerland 相似文献
8.
9.
10.