全文获取类型
收费全文 | 832篇 |
免费 | 41篇 |
国内免费 | 2篇 |
专业分类
耳鼻咽喉 | 3篇 |
儿科学 | 53篇 |
妇产科学 | 4篇 |
基础医学 | 64篇 |
口腔科学 | 19篇 |
临床医学 | 45篇 |
内科学 | 94篇 |
皮肤病学 | 63篇 |
神经病学 | 13篇 |
特种医学 | 51篇 |
外科学 | 91篇 |
综合类 | 278篇 |
预防医学 | 33篇 |
眼科学 | 3篇 |
药学 | 20篇 |
1篇 | |
肿瘤学 | 40篇 |
出版年
2022年 | 4篇 |
2021年 | 9篇 |
2020年 | 9篇 |
2019年 | 9篇 |
2018年 | 18篇 |
2017年 | 14篇 |
2016年 | 9篇 |
2015年 | 26篇 |
2014年 | 26篇 |
2013年 | 30篇 |
2012年 | 25篇 |
2011年 | 29篇 |
2010年 | 64篇 |
2009年 | 47篇 |
2008年 | 54篇 |
2007年 | 47篇 |
2006年 | 46篇 |
2005年 | 27篇 |
2004年 | 49篇 |
2003年 | 23篇 |
2002年 | 28篇 |
2001年 | 29篇 |
2000年 | 18篇 |
1999年 | 19篇 |
1998年 | 26篇 |
1997年 | 30篇 |
1996年 | 28篇 |
1995年 | 18篇 |
1994年 | 21篇 |
1993年 | 10篇 |
1992年 | 9篇 |
1991年 | 2篇 |
1990年 | 6篇 |
1989年 | 5篇 |
1988年 | 7篇 |
1987年 | 5篇 |
1986年 | 8篇 |
1985年 | 5篇 |
1984年 | 3篇 |
1983年 | 3篇 |
1982年 | 6篇 |
1981年 | 4篇 |
1980年 | 2篇 |
1978年 | 5篇 |
1977年 | 2篇 |
1976年 | 4篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1955年 | 1篇 |
1953年 | 1篇 |
排序方式: 共有875条查询结果,搜索用时 15 毫秒
41.
42.
The word tracheostomy derived from two greek words meaning ‘I cut the trachea’ has been known for about 3500 yrs. The process has evolved over the years and has undergone revolutionary changes in the methodology, instrumentation and indications. Although tracheostomy is now commonly used the complication rate remains high. In our series it was 48% which is comparable with other series. The purpose of this paper is to discuss the complications of tracheostomy with special attention to their management and prevention.KEY WORDS: Complications, Tracheostomy 相似文献
43.
The effects of an ionic contrast agent, meglumine iothalamate (Conray-60), and two newer low-osmolality radiographic contrast media, sodium meglumine ioxaglate (Hexabrix) and iopamidol (B-15,000), on platelet aggregation and secretion responses were studied. All three agents inhibited platelet responses during stimulation with adenosine diphosphate (ADP), epinephrine, and collagen. Platelet function was inhibited by iothalamate at concentrations of 11 mg iodine/ml and above, and by the newer agents at concentrations above 30 mg iodine/ml. Addition of exogenous calcium decreased the iothalamate-induced inhibition of aggregation but did not improve dense granule secretion. There was no consistent effect of exogenous calcium on platelet inhibition by iopamidol and ioxaglate. These studies indicate that the newer agents inhibit platelet function less than iothalamate does, and that chelation of Ca2+ may not be the major mechanism of platelet inhibition by contrast agents. 相似文献
44.
AI Zijlstra GD Offner NH Afdhal M van Overveld GN Tytgat AK Groen 《Gastroenterology》1996,110(6):1926-1935
BACKGROUND & AIMS: Many putative pronucleating proteins have been isolated from the biliary concanavalin A (con A)-binding fraction. The pronase resistance of the overall nucleating-promoting activity was almost never taken into consideration. The aim of this study was to identify the major pronase-resistant con A-binding glycoproteins. METHODS: Pronase-treated and -untreated con A-binding glycoproteins were separated on a Superose 12 gel permeation column (Pharmacia, Uppsala, Sweden) and tested in a crystal growth assay. Proteins were identified by amino-terminal sequencing. RESULTS: Con A-binding pronucleating activity eluted in two peaks on the Superose column. This activity was unaltered after pronase treatment. Activity peak I contained too little protein to allow amino-terminal sequencing. In activity peak II, the major pronase-resistant con A-binding glycoproteins were identified as alpha 1-antitrypsin and alpha 1- antichymotrypsin. The 130-kilodalton nucleation promoter was identified as aminopeptidase N, but the full pronase resistance of this protein, reported earlier, was not confirmed. Immunoabsorptive removal of alpha 1-antitrypsin and alpha 1-antichymotrypsin and immunopurification showed that only alpha 1-antichymotrypsin had pronucleating activity. CONCLUSIONS: The pronase resistance of the nucleating-promoting activity of the con A-binding glycoprotein fraction was confirmed. An important part of this activity could be attributed to alpha 1- antichymotrypsin. It is an acute-phase protein, as are many other pronucleating proteins, which might indicate a general mechanism of action in gallstone formation. (Gastroenterology 1996 Jun;110(6):1926-35) 相似文献
45.
VS Gurunadh A Banarji S Patyal AK Upadhyay TS Ahluwalia RP Gupta M Bhaduria 《Medical Journal Armed Forces India》2010,66(2):125-128
Background
Vitreous substitutes presently in use for intraoperative tamponade are perfluorocarbon liquids (PFCL) and for post operative tamponade are silicon oil (SO), sulphur hexafluoride (SF6) and perfluorocarbon gas (PFC). Several factors are important for a thorough understanding of each of these vitreous substitutes. The absorption or necessity for removal, indications for use (including clinical studies and special surgical methods), additives and complications of use have to be considered.Methods
Three port standard pars plana vitrectomy was performed in 60 consecutive cases requiring intra-vitreal intervention. PFCL was used intra-operatively in 30 cases (PFCL group and X group). The eyes were implanted with SO (silicon oil subgroup), PFC (C3F8 sub-group) and SF6 (SF6 sub-group) in twenty cases each. Apart from best corrected visual acuity (BCVA), the retinal status and the longevity of gas when used, changes and reaction in both the anterior and posterior segments were noted.Result
The difference of postoperative BCVA in the PFCL and non-PFCL groups was statistically significant with p < 0.001. In both the PFCL and non-PFCL groups the difference between preoperative and postoperative BCVA was statistically significant with p < 0.0001. All three vitreous substitutes studied are effective given the case where they had been utilised.Conclusion
PFCL is invaluable in the management of complicated retinal detachment (RD). Where a vitreous microsurgery is indicated, the visual outcome is good. SF6 is useful for short-term tamponade. Silicon oil and C3F8 are useful for longer tamponade.Key Words: Tamponade, Perfluorocarbon liquids, Silicon oil, Sulphur hexafluoride, Perfluorocarbon gas, Retinal detachment 相似文献46.
47.
48.
49.
50.
MUAMMER SEYHAN BAAK KANDI COKUN HÜLYA SALAM HAMDI ÖZCAN YELDA KARINCAOLU 《Pediatrics international》2006,48(6):525-530
BACKGROUND: The present study was aimed to define the gender ratio, familial occurrence, age of onset, precipitating factors, clinical types, nail and joint involvement of psoriasis in childhood and adolescence in Turkey. METHODS: A total of 61 children with psoriasis under 18 years old were evaluated retrospectively, for age, gender, age of disease onset, family history, concomitant disease, the clinical type of psoriasis, clinical localization, nail and joint involvement and treatment modalities. RESULTS: Of the patients, 23 (37.70%) were boys and 38 (62.30%) were girls. Mean age was 9.28 +/- 4.02 years in girls and 11.18 +/- 3.85 years in boys (9.96 +/- 4.03 years in all children). Mean age at the onset of the disease was 6.81 +/- 4.11 years in girls and 7.03 +/- 4.28 years in boys (6.89 +/- 4.14 years in all patients). In 14 (23%) cases, a positive family history was detected. The most frequent probable triggering factors were upper respiratory tract infections (14.8%) and positive throat culture for A group ss-hemolytic streptococcus (21.3%). Frequency of emotional stress and psychiatric morbidity were 54% and 9.8%, respectively. The most frequent localizations at onset were trunk (44.3%), extremities (54.0%), and scalp (36.0%). Three children (4.9%) had a history of dissemination from psoriatic diaper rash. In total, 51 (83.6%) patients presented with psoriasis vulgaris, eight (13.1%) with generalized pustular psoriasis, and the remaining two (3.3%) with erythrodermic psoriasis. CONCLUSION: The incidence of psoriasis among dermatological patients in childhood and adolescence was 3.8%. The disease tends to appear earlier in girls than boys. The authors suggested that stress and upper respiratory infections are the most important triggering factors in childhood and adolescence psoriasis. 相似文献