全文获取类型
收费全文 | 29596篇 |
免费 | 1360篇 |
国内免费 | 200篇 |
专业分类
耳鼻咽喉 | 322篇 |
儿科学 | 547篇 |
妇产科学 | 705篇 |
基础医学 | 3404篇 |
口腔科学 | 1524篇 |
临床医学 | 2240篇 |
内科学 | 7995篇 |
皮肤病学 | 444篇 |
神经病学 | 2751篇 |
特种医学 | 1113篇 |
外科学 | 4256篇 |
综合类 | 113篇 |
一般理论 | 7篇 |
预防医学 | 1577篇 |
眼科学 | 439篇 |
药学 | 1649篇 |
中国医学 | 119篇 |
肿瘤学 | 1951篇 |
出版年
2023年 | 176篇 |
2022年 | 420篇 |
2021年 | 808篇 |
2020年 | 459篇 |
2019年 | 637篇 |
2018年 | 824篇 |
2017年 | 576篇 |
2016年 | 698篇 |
2015年 | 804篇 |
2014年 | 1109篇 |
2013年 | 1496篇 |
2012年 | 2284篇 |
2011年 | 2447篇 |
2010年 | 1412篇 |
2009年 | 1248篇 |
2008年 | 2130篇 |
2007年 | 2189篇 |
2006年 | 2013篇 |
2005年 | 2023篇 |
2004年 | 1799篇 |
2003年 | 1559篇 |
2002年 | 1449篇 |
2001年 | 198篇 |
2000年 | 131篇 |
1999年 | 179篇 |
1998年 | 241篇 |
1997年 | 192篇 |
1996年 | 184篇 |
1995年 | 145篇 |
1994年 | 132篇 |
1993年 | 91篇 |
1992年 | 97篇 |
1991年 | 90篇 |
1990年 | 73篇 |
1989年 | 76篇 |
1988年 | 77篇 |
1987年 | 51篇 |
1986年 | 52篇 |
1985年 | 42篇 |
1984年 | 88篇 |
1983年 | 56篇 |
1982年 | 72篇 |
1981年 | 45篇 |
1980年 | 27篇 |
1979年 | 28篇 |
1978年 | 31篇 |
1977年 | 31篇 |
1976年 | 21篇 |
1974年 | 18篇 |
1973年 | 24篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
Donato Casella Marco Bernini Lapo Bencini Jenny Roselli Maria Teresa Lacaria Jacopo Martellucci Roberto Banfi Claudio Calabrese Lorenzo Orzalesi 《European journal of plastic surgery》2014,37(11):599-604
Background
Immediate implant reconstruction after a conservative mastectomy is an attractive option made easier by prosthetic devices. Titanized polypropylene meshes are used as a hammock to cover the lower lateral implant pole. We conducted a prospective nonrandomized single-institution study of reconstructions using titanium-coated meshes either in a standard muscular mesh pocket or in a complete subcutaneous approach. The complete subcutaneous approach means to wrap an implant with titanized mesh in order to position the implant subcutaneously and spare muscles.Methods
Between November 2011 and January 2014, we performed immediate implant breast reconstructions after conservative mastectomies using TiLoop® Bra, either with the standard retropectoral or with a prepectoral approach. Selection criteria included only women with normal Body Mass Index (BMI), no large and very ptotic breasts, no history of smoking, no diabetes, and no previous radiotherapy. We analyzed short-term outcomes of such procedures and compared the outcomes to evaluate implant losses and surgical complications.Results
A total of 73 mastectomies were performed. Group 1 comprised 29 women, 5 bilateral procedures, 34 reconstructions, using the standard muscular mesh pocket. Group 2 comprised 34 women, 5 bilateral procedures, 39 reconstructions with the prepectoral subcutaneous technique. Baseline and oncologic characteristics were homogeneous between the two groups. After a median follow-up period of 13 and 12 months, respectively, no implant losses were recorded in group 1, and one implant loss was recorded in group 2. We registered three surgical complications in group 1 and two surgical complications in group 2.Conclusions
Titanium-coated polypropylene meshes, as a tool for immediate definitive implant breast reconstruction, resulted as safe and effective in a short-term analysis, both for a retropectoral and a totally subcutaneous implant placement. Long-term results are forthcoming. A strict selection is mandatory to achieve optimal results. Level of Evidence: Level II, therapeutic study. 相似文献992.
Prenatal ethanol exposure modifies postnatal affinity to the drug, increasing the probability of ethanol use and abuse. The present study tested developing rats (5-day-old) in a novel operant technique to assess the degree of ethanol self-administration as a result of prenatal exposure to low ethanol doses during late gestation. On a single occasion during each of gestational days 17–20, pregnant rats were intragastrically administered ethanol 1 g/kg, or water (vehicle). On postnatal day 5, pups were tested on a novel operant conditioning procedure in which they learned to touch a sensor to obtain 0.1% saccharin, 3% ethanol, or 5% ethanol. Immediately after a 15-min training session, a 6-min extinction session was given in which operant behavior had no consequence. Pups were positioned on a smooth surface and had access to a touch-sensitive sensor. Physical contact with the sensor activated an infusion pump, which served to deliver an intraoral solution as reinforcement (Paired group). A Yoked control animal evaluated at the same time received the reinforcer when its corresponding Paired pup touched the sensor. Operant behavior to gain access to 3% ethanol was facilitated by prenatal exposure to ethanol during late gestation. In contrast, operant learning reflecting ethanol reinforcement did not occur in control animals prenatally exposed to water only. Similarly, saccharin reinforcement was not affected by prenatal ethanol exposure. These results suggest that in 5-day-old rats, prenatal exposure to a low ethanol dose facilitates operant learning reinforced by intraoral administration of a low-concentration ethanol solution. This emphasizes the importance of intrauterine experiences with ethanol in later susceptibility to drug reinforcement. The present operant conditioning technique represents an alternative tool to assess self-administration and seeking behavior during early stages of development. 相似文献
993.
Roberto Sebastián Miranda-Morales Michael E. NizhnikovDustin H. Waters Norman E. Spear 《Alcohol》2014
Ethanol induces appetitive, aversive, and anxiolytic effects that are involved in the development of ethanol use and dependence. Because early ethanol exposure produces later increased responsiveness to ethanol, considerable effort has been devoted to analysis of ethanol's appetitive and aversive properties during early ontogeny. Yet, there is a relative scarcity of research related to the anxiolytic effects of ethanol during early infancy, perhaps explained by a lack of age-appropriate tests. The main aim of this study was to validate a model for the assessment of ethanol's anxiolytic effects in the infant rat (postnatal days 13–16). The potentially anxiolytic effects of ethanol tested included: i) amelioration of conditioned place aversion, ii) ethanol intake in the presence of an aversive conditioned stimulus, iii) the inhibitory behavioral effect in an anxiogenic environment, and iv) innate aversion to a brightly illuminated area in a modified light/dark paradigm. Ethanol doses employed across experiments were 0.0, 0.5, and 2.0 g/kg. Results indicated that a low ethanol dose (0.5 g/kg) was effective in attenuating expression of a conditioned aversion. Ethanol intake, however, was unaffected by simultaneous exposure to an aversive stimulus. An anxiogenic environment diminished ethanol-induced locomotor stimulation. Finally, animals given 0.5 g/kg ethanol and evaluated in a light/dark box showed increased time spent in the illuminated area and increased latency to escape from the brightly lit compartment than rats treated with a higher dose of ethanol or vehicle. These new results suggest that ethanol doses as low as 0.5 g/kg are effective in ameliorating an aversive and/or anxiogenic state in preweanling rats. These behavioral preparations can be used to assess ethanol's anxiolytic properties during early development. 相似文献
994.
Walderez P. Gaeti Paulo R. Obreli-Neto Roberto K. N. Cuman 《Central European Journal of Medicine》2014,9(2):231-234
Several case reports have associated the combined use of thyroid drugs and oral anticoagulants, like coumarin, with overanticoagulation. However, this effect has never been described for phenprocoumon, a coumarin derivate that is widely prescribed in continental European countries and in Latin America. We describe a 62-year-old female who had an unexpectedly labile anticoagulation profile when levothyroxine (Puran T4®) was added to her drug therapy regimen, which included phenprocoumon (Marcoumar®). This resulted in an elevated international normalized ratio (INR) that was unrecordable and bleeding (macroscopic hematuria) that required hospitalization and treatment with vitamin K. The patient had been taking phenprocoumon for almost ten years for systemic embolism prophylaxis because of her history of mechanical bileaflet mitral valve prosthesis. One month before the events described, the patient was prescribed sodium levothyroxine (50 mcg daily) to treat hypothyroidism (TSH = 40 µU/mL; reference range, 0.40–4.0 µU/mL). Approximately 3 weeks prior to initiation of levothyroxine treatment, her INR was 2.8. A drug interaction was therefore suspected. The Horn Drug Interaction Probability Scale (DIPS) indicated a probable interaction between oral phenprocoumon and levothyroxine in this case. Clinicians should be aware that levothyroxine may interact with oral phenprocoumon, resulting in overanticoagulation. 相似文献
995.
996.
Marianna Redoni Sophie Yacoub Laura Rivino Daniele Roberto Giacobbe Roberto Luzzati Stefano Di Bella 《Reviews in medical virology》2020,30(4)
Dengue is an emerging mosquito‐borne viral infection with increasing reports of outbreaks. The clinical picture ranges from a benign febrile illness through to severe and potentially fatal manifestations. No specific anti‐viral treatment exists, and therapy only consists of supportive care. During the last three decades, several attempts to develop an effective vaccine have been made. The first dengue vaccine to obtain licensure was Dengvaxia, which was authorized in 2015 and is currently available in over 20 countries. Its use has been approved with strict limitations regarding age and serostatus of the recipients, highlighting the necessity for a more safe and efficacious vaccine. At present several vaccine, candidates are undergoing clinical and pre‐clinical trials. The most advanced candidates are TDV and TDV 003/005, two live‐attenuated vaccines, but another 15 vaccines are under development, introducing novel immunization strategies to the traditional dengue vaccine scenario. This work reviews the current research status on dengue vaccines. 相似文献
997.
Aldo Bonaventura Federico Carbone Alessandra Vecchié Jennifer Meessen Sandra Ferraris Eduardo Beck Roberto Keim Silvia Minetti Edoardo Elia Daniele Ferrara Anna Maria Ansaldo Deborah Novelli Pietro Caironi Roberto Latini Fabrizio Montecucco 《European journal of clinical investigation》2020,50(10):e13333
998.
999.
1000.