全文获取类型
收费全文 | 1837660篇 |
免费 | 128887篇 |
国内免费 | 4142篇 |
专业分类
耳鼻咽喉 | 23759篇 |
儿科学 | 59377篇 |
妇产科学 | 49426篇 |
基础医学 | 261495篇 |
口腔科学 | 53811篇 |
临床医学 | 159654篇 |
内科学 | 364654篇 |
皮肤病学 | 42145篇 |
神经病学 | 142966篇 |
特种医学 | 67325篇 |
外国民族医学 | 243篇 |
外科学 | 273684篇 |
综合类 | 39677篇 |
现状与发展 | 4篇 |
一般理论 | 559篇 |
预防医学 | 141422篇 |
眼科学 | 44060篇 |
药学 | 134590篇 |
7篇 | |
中国医学 | 5009篇 |
肿瘤学 | 106822篇 |
出版年
2021年 | 15156篇 |
2019年 | 16061篇 |
2018年 | 24108篇 |
2017年 | 17870篇 |
2016年 | 19333篇 |
2015年 | 21970篇 |
2014年 | 29763篇 |
2013年 | 43174篇 |
2012年 | 61701篇 |
2011年 | 64921篇 |
2010年 | 37502篇 |
2009年 | 34263篇 |
2008年 | 59242篇 |
2007年 | 63034篇 |
2006年 | 63131篇 |
2005年 | 59988篇 |
2004年 | 57640篇 |
2003年 | 54527篇 |
2002年 | 52486篇 |
2001年 | 95226篇 |
2000年 | 97478篇 |
1999年 | 79940篇 |
1998年 | 20410篇 |
1997年 | 17709篇 |
1996年 | 17795篇 |
1995年 | 17114篇 |
1994年 | 15622篇 |
1993年 | 14330篇 |
1992年 | 59146篇 |
1991年 | 56855篇 |
1990年 | 54544篇 |
1989年 | 52125篇 |
1988年 | 47459篇 |
1987年 | 46191篇 |
1986年 | 43523篇 |
1985年 | 41217篇 |
1984年 | 30220篇 |
1983年 | 25683篇 |
1982年 | 14329篇 |
1979年 | 26578篇 |
1978年 | 18274篇 |
1977年 | 15588篇 |
1976年 | 14502篇 |
1975年 | 15317篇 |
1974年 | 18615篇 |
1973年 | 17947篇 |
1972年 | 16648篇 |
1971年 | 15409篇 |
1970年 | 14317篇 |
1969年 | 13460篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Raúl González-García Francisco J Rodríguez-Campo Verónica Escorial-Hernández Mario F Mu?oz-Guerra Jesús Sastre-Pérez Luis Naval-Gías José L Gil-Díez Usandizaga 《Journal of oral and maxillofacial surgery》2006,64(11):1587-1591
PURPOSE: Temporomandibular joint (TMJ) arthroscopy has been considered a safe surgical procedure in the treatment of TMJ derangement. However, it is not exempt from complications. This study evaluates the complications of arthroscopy in patients with internal derangement of TMJ. PATIENTS AND METHODS: Five hundred consecutive patients (670 joints) with TMJ derangement who underwent arthroscopy between 1995 and 2004 were retrospectively analyzed. All the patients were classified as II to V in the Wilkes classification. Lysis and lavage, electrocautery of the posterior ligament, injection of corticoids, injection of ethanolamine, myotomy of lateral pterygoid muscle attachments, myotomy and electrocautery, motor debridement, injection of sodium hyaluronate, and meniscal suture were performed in different patients. RESULTS: Complications were recognized during or immediately after the surgery. They were observed in 5 of 341 (1.26%) arthroscopies of the right TMJ and 4 of 329 (1.21%) arthroscopies of the left TMJ. A 1.34% complication rate was found in the whole series. No blood clots within the external auditory canal were observed. Bleeding within the superior TMJ space was observed in 57 cases (8.5%), 36 of them in the right TMJ and 21 in the left TMJ, but they were not considered as true complications. Lacerations of the external auditory canal were found in 2 cases (0.3%), with no cases of perforation of the tympanic membrane. Lesion of the auriculotemporal nerve was observed in a case. Paresia of the facial nerve was found in 4 cases (0.6%). Alteration of visual accuracy of the ipsilateral eye was also observed in a patient immediately after the surgery. CONCLUSION: Special care must be taken to reduce complications within the upper joint space by means of an adequate instrumentation and by paying attention to essential points of the arthroscopic technique. 相似文献
992.
993.
Z. Malazgirt K. Topgul S. Sokmen S. Ersin A. G. Turkcapar H. Gok N. Gonullu M. Paksoy M. Ertem 《Hernia》2006,10(4):326-330
Most of the papers published on spigelian hernia are either case reports or small retrospective series. In this prospective
multicenter study, we aimed to outline the specific features of spigelian hernias and patients’ characteristics more clearly.
Surgeons enrolled patients to be entered into the database as they diagnosed and treated the hernias at will. The baseline
and surgical outcome parameters were noted in each patient. A painful mass was the main presenting complaint in half of 34
patients. Accurate preoperative diagnosis was possible in 31 patients. Open intraperitoneal mesh repair was the preferred
technique. The mean hospital stay and time until return to normal daily activities were 4.1 and 15.6 days. Although a rare
condition, diagnosis of a spigelian hernia is not difficult once remembered. Its surgical repair seems to cause few complications
and is very well tolerated by the patient. 相似文献
994.
The performance of a tooth replacement by using a dental implant relies on the mechanical and biological capability of the anatomical substitute to restore lost physiological functions. The design of an implant device able to properly replace the physiological tooth requires the study of the load transfer mechanism at the implant-bone interface and the understanding of the relevance of the periodontal ligament (PDL) in this mechanism. The PDL is a connective soft tissue that provides the fixation of the tooth in its bone-socket and the attenuation of occlusal loads. It also provides the ground cells that are involved in the remodelling process, induced by a change in the stress-strain pattern of the alveolar bone and also in the cementum of the tooth root. The purpose of this study was to determine the PDL effects on the dynamic load transfer mechanism, from the tooth to the alveolar bone, evaluating the equivalent dynamic stiffness of the ligament structure. A porcine fresh mandible with a tooth was used within the study, applying an experimental procedure to identify the dynamic transmissibility of the entire system. The transmissibility function provided information about the stiffness and damping of the PDL, information that can assist the design of an improved dental implant system. 相似文献
995.
Cari Borrás 《Pan American journal of public health》2006,20(2-3):173-187
This report summarizes and analyzes the responses of various organizations that provided assistance to the National Oncology Institute (Instituto Oncológico Nacional, ION) of Panama following the overexposure of 28 radiation therapy patients at the ION in late 2000 and early 2001. The report also looks at the long-term measures that were adopted at the ION in response to the overexposure incident, as well as implications that the incident has for other cancer treatment centers worldwide. In March 2001, the director of the ION was notified of serious overreactions in patients undergoing radiation therapy for cancer treatment. Of the 478 patients treated for pelvic cancers between August 2000 and March 2001, 3 of them had died, possibly from an overdose of radiation. In response, the Government of Panama invited international experts to carry out a full investigation of the situation. Medical physicists from the Pan American Health Organization (PAHO) were among those invited. They ascertained that 56 patients treated with partially blocked teletherapy fields for cancers of the uterine cervix, endometrium, prostate, or rectum, had had their treatment times calculated using a computerized treatment planning system. PAHO's medical physicists calculated the absorbed doses received by the patients and found that, of these 56 patients, only 11 had been treated with acceptable errors of +/-5%. The doses received by 28 of the 56 patients had errors ranging from +10 to +105%. These are the patients identified by ION physicists as overexposed. Twenty-three of the 28 overexposed patients had died by September 2005, with at least 18 of the deaths being from radiation effects, mostly rectal complications. The clinical, psychological, and legal consequences of the overexposures crippled cancer treatments in Panama and prompted PAHO to assess radiation oncology practices in the countries of Latin American and the Caribbean. ION clinicians evaluated the outcome of 125 non-overexposed patients who had been treated in the same time period and for the same cancer sites as the overexposed patients. The clinicians uncovered a larger recurrence of cervical cancers than expected. The finding prompted PAHO to launch an initiative for the accreditation of radiation oncology centers in Latin America and the Caribbean, working in collaboration with professional societies for radiation oncologists, medical physicists, and radiotherapy technologists. The Latin American Association for Radiation Oncology (Asociación Latinoamericana de Terapia Radiante Oncológica) has established an accreditation commission. Accreditation will require that centers implement a comprehensive radiation oncology quality assurance program that follows international guidelines. Statistical data on patient outcomes will be collected in order to document needs in radiotherapy centers in Latin America and the Caribbean and to define future strategies for cancer treatment. 相似文献
996.
997.
998.
To evaluate use of a digital photostimulable phosphor imaging system in the neonatal nursery, 150 newborns were divided into three groups of 50. In the first two groups, screen-film and computed radiographs of the chest were obtained at the same radiation exposure; in the third group, computed radiographs were obtained with a 50% dose reduction (half-exposure computed radiographs). All images were blindly evaluated by three readers who scored the quality of visualization of the mediastinum, lung, bone, soft tissues, and endotracheal and nasogastric tubes, and also image density. No statistical differences in visualization of tubes existed among the three groups. Visualization of the mediastinum, lung, bones, and soft tissues was statistically significantly better on computed radiographs than on half-exposure computed radiographs; visualization of the lungs, bones, and soft tissues was statistically significantly better on screen-film radiographs than half-exposure computed radiographs. Image density was statistically better on computed and half-exposure computed radiographs than on screen-film radiographs. 相似文献
999.
Sheela R Geraghty Barbara S Davidson Barbara B Warner Amy L Sapsford Jeanne L Ballard Betsy A List Rachel Akers Ardythe L Morrow 《Journal of human lactation》2005,21(1):59-66
Although there are well-established clinical human milk banks in the United States, there are no milk banks specifically intended to foster research on human milk. The authors' goal was to establish a milk bank with a core data set to support exploratory and hypothesis-driven studies on human milk. Donations to the Cincinnati Children's Research Human Milk Bank are accepted within the context of ongoing, hypothesis-driven research or on an ad hoc basis. Donors must give informed consent, and scientists wishing to use the samples must have Institutional review board approval for their use. Development of more research human milk banks can potentially provide resources for multidisciplinary collaboration and advance the study of human milk and lactation. 相似文献
1000.
S Lori Brown Roselie A Bright Diane E Dwyer Betsy Foxman 《Journal of human lactation》2005,21(2):169-174
Breast pumps are medical devices used to express milk and maintain the milk supply. The purpose of this study was to characterize adverse events reported to the United States Food and Drug Administration (FDA) on breast pumps. Thirty-seven adverse event reports on breast pumps were identified from the Manufacturer and User Facility Device Experience database between 1992 and 2003. Four additional reports were found in the Device Experience Network database from 1992 to 1996. The most commonly reported adverse events for electric breast pumps were pain, soreness, or discomfort; the need for medical intervention; and breast tissue damage. Most frequently reported problems for manual breast pumps were breast tissue damage and infection. Contamination of breast milk during pumping was also reported. Breast pump adverse events are likely underreported to the FDA. Reporting adverse events is important for improving the design and manufacture of breast pumps and subsequently decreasing adverse events. 相似文献