全文获取类型
收费全文 | 10572篇 |
免费 | 718篇 |
国内免费 | 30篇 |
专业分类
耳鼻咽喉 | 87篇 |
儿科学 | 423篇 |
妇产科学 | 290篇 |
基础医学 | 1678篇 |
口腔科学 | 188篇 |
临床医学 | 1461篇 |
内科学 | 1994篇 |
皮肤病学 | 171篇 |
神经病学 | 1058篇 |
特种医学 | 269篇 |
外科学 | 1035篇 |
综合类 | 64篇 |
一般理论 | 9篇 |
预防医学 | 929篇 |
眼科学 | 166篇 |
药学 | 633篇 |
中国医学 | 11篇 |
肿瘤学 | 854篇 |
出版年
2023年 | 82篇 |
2022年 | 87篇 |
2021年 | 212篇 |
2020年 | 165篇 |
2019年 | 232篇 |
2018年 | 291篇 |
2017年 | 207篇 |
2016年 | 257篇 |
2015年 | 263篇 |
2014年 | 360篇 |
2013年 | 549篇 |
2012年 | 740篇 |
2011年 | 733篇 |
2010年 | 413篇 |
2009年 | 365篇 |
2008年 | 714篇 |
2007年 | 693篇 |
2006年 | 648篇 |
2005年 | 674篇 |
2004年 | 588篇 |
2003年 | 522篇 |
2002年 | 519篇 |
2001年 | 149篇 |
2000年 | 92篇 |
1999年 | 120篇 |
1998年 | 125篇 |
1997年 | 98篇 |
1996年 | 85篇 |
1995年 | 90篇 |
1994年 | 71篇 |
1993年 | 65篇 |
1992年 | 74篇 |
1991年 | 75篇 |
1990年 | 74篇 |
1989年 | 61篇 |
1988年 | 73篇 |
1987年 | 63篇 |
1986年 | 62篇 |
1985年 | 74篇 |
1984年 | 50篇 |
1983年 | 48篇 |
1982年 | 31篇 |
1981年 | 45篇 |
1980年 | 33篇 |
1979年 | 28篇 |
1978年 | 28篇 |
1977年 | 21篇 |
1976年 | 21篇 |
1971年 | 24篇 |
1969年 | 20篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Antonia Zapf Marianne Huebner Geraldine Rauch Meinhard Kieser 《Statistics in medicine》2019,38(4):695-701
Biostatisticians play an important role in medical research. They are co-responsible for an appropriate and efficient study design, they are involved in monitoring the study conduct, they plan and perform the data analysis, and they are involved in interpreting and publishing the results. However, how are the biostatisticians prepared for their tasks and responsibilities? Graduate programs in biostatistics are being offered, but some practicing biostatisticians completed their studies in a mathematical or epidemiological program, or obtained their degree in subject-specific fields (such as medicine or biology). Therefore, the expertise and the competencies can vary widely between the individual biostatisticians, also depending on the application field. In this article, focusing on European and US practices, we discuss the required professional expertise for the main areas of applications in the medical field as well as the necessary soft skill competencies of a biostatistician. 相似文献
2.
Olle Zetterström Christer Andersson Leif Eriksson ers Fredriksson Johan Friskopp Gunnar Heden Bernt Jansson Tord Lundgren Rolf Nilveus ers Olsson Stefan Renvert Lars Salonen Lars Sjöström ers Winell ers Östgren Stina Gestrelius 《Journal of clinical periodontology》1997,24(9):697-704
Abstract The aim of the present clinical trial was to test tolerability during 2 treatments with EMDOGAIN® in a large number of patients. An open, controlled study design in 10 Swedish specialist clinics was chosen, with a test group of 107 patients treated with EMDOGAIN® in connection with periodontal surgery at 2 surgical test sites per patient. The procedures were performed 2 to 6 weeks apart on one-rooted teeth with at least 4 mm deep intraosseous lesions. A control group of 33 patients underwent flap surgery without EMDOGAIN® at I comparable site. In total 214 test and 33 control surgeries were performed. Serum samples were obtained from test patients for analysis of total and specific antibody levels. 10 of the patients had samples taken before and after the first surgery. 56 other samples were taken after one treatment with EMDOGAIN®, and 63 after 2 treatments. None of the samples, not even from allergy-prone patients after 2 treatments, indicated deviations from established baseline ranges. This indicates that the immunogenic potential of EMDOGAIN® is extremely low when applied in conjunction with periodontal surgery. Comparison between the test and control groups demonstrated the same type and frequency of post-surgical experiences, i.e., reactions caused by the surgical procedure itself. Clinical probing and radiographic evaluation was performed at baseline and 8 months postsurgery. About half of the patients (44 test and 21 control) were also evaluated after 3 years. There was a significant difference between the test and control results at 8 months post surgery. and this difference had increased further at the 3 year follow-up. The 2.5–3 mm increase in attachment and bone level after treatment with EMDOGAIN® was of the same magnitude as seen in the studies with split-mouth design aiming for lest of effectiveness of EMDOGAIN®. 相似文献
3.
Cerebral function in normoxia and its reactions to standard periods of hypoxia of increasing severity were studied in 30 newborn guinea pigs less than 3 days old. Intrauterine growth retardation was induced either by uterine artery ligation at midgestation or by feeding the female in late gestation with khat leaves, an amphetamine-like stimulant chewed by men and women in several countries in eastern Africa and Arabia. After spontaneous delivery, the neonates were anesthetized and ventilated. Cardiovascular, metabolic, and neurophysiologic (somatosensory evoked potentials) parameters were monitored. Under normoxia, the khat-exposed group showed prolonged latency of the primary response of the somatosensory evoked potentials and a reduced amount of secondary components. Under hypoxia, this group also has a greater reduction of amplitude of the somatosensory evoked potentials. It is concluded that khat exposure during fetal life has an impact on the cerebral function during the neonatal period (at least up to 3 days of age) which is not solely explained by the concomitantly produced growth retardation. 相似文献
4.
5.
Signe S?nderkaer Marianne Schmiegelow Henrik Carstensen Lars B?geskov Nielsen J?rn Müller Kjeld Schmiegelow 《Journal of clinical oncology》2003,21(7):1347-1351
PURPOSE: To evaluate the pattern of neurological late effects in patients who have received surgery only for a brain tumor in childhood and to identify possible risk factors for neurological sequelae. PATIENTS AND METHODS: The medical, histologic, and operative records were reviewed for 65 consecutive patients operated for a benign brain tumor from 1970 to 1997, and all patients were re-examined after a median length of follow-up of 10.7 years. Thirty-four patients had posterior fossa tumors, 22 patients had cerebral hemisphere tumors, and nine patients had midline tumors. RESULTS: At the time of follow-up, 20 patients (31%) had no neurological deficits, 22 patients (34%) had minor deficits that did not interfere with their daily life activities, and 23 patients (35%) had moderate or severe deficits such as severe ataxia, spastic paresis, seriously reduced vision, or epilepsy with more than two seizures per year. Fourteen of the 31 patients (45%) registered with ataxia preoperatively had recovered fully. Six of seven patients had persistence of a pre- or postoperatively developed hemiparesis. Thirteen of 23 patients had persistence of cranial nerve deficits that developed second to surgery. Fifty-five percent of the 18 patients with seizures at diagnosis were seizure-free at follow-up. At follow-up both ataxia and hemiparesis were significantly more frequent among females (P =.02 and P =.03, respectively). CONCLUSION: In patients who received operation as the only treatment for their brain tumor, there was a good chance of total or partial recovery of preoperative and postoperative neurological deficits, although only one third of the patients will have no long-term neurological deficits. 相似文献
6.
Udo Lorenz Marianne Abele-Horn Dieter Bussen Arnulf Thiede 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》2007,392(6):761-765
Background To our best knowledge, Panton–Valentine leucocidin (PVL)-positive methicillin-sensitive Staphylococcus aureus (MSSA) has not been described yet as cause for severe pyomyositis.
Case report We present a 23-year-old apparently healthy male patient without any typical predisposing findings who developed severe pyomyositis
secondary to an operated pilonidal cyst. In the follow-up, the patient showed signs of immunocompromisation. The causative
agent for purulent infection of multiple muscles was a MSSA strain harbouring PVL toxin.
Results In the reported case, aggressive antibiotic and surgical treatment with additional application of immunoglobulins has lead
to recovery from the disease without relapse.
Conclusions PVL-positive S. aureus are associated with skin diseases, multiple abscesses and often complicated by severe sepsis and necrotising pneumonia. Under
such circumstances, the mortality rate can reach up to 75%. In addition, the PVL toxin can cause immunocompromisation and
might be therefore involved in the aetiology of pyomyositis. Aggressive antibiotic and surgical treatment with additional
application of immunoglobulins is recommended for treatment. 相似文献
7.
8.
Anita Rachlis Jonathan Angel Marianne Harris Richard Lalonde Fiona Smaill Cecile Tremblay Chris Tsoukas Sharon Walmsley 《The Canadian Journal of Infectious Diseases & Medical Microbiology》2006,17(3):155-163
BACKGROUND AND OBJECTIVES: An eight-member group consisting of Canadian infectious disease and immunology specialists and a family physician with significant experience in HIV management was convened to update existing recommendations, specifically intended for use by Canadian HIV-treating physicians, on the appropriate use of enfuvirtide in HIV/AIDS patients with resistance to other antiretroviral drugs. METHODS: Evidence from the literature and expert opinions of the group members formed the basis of the guidelines. Comments on the draft guidelines were obtained from other physicians across Canada with HIV expertise. The final guidelines represent the group's consensus agreement. RESULTS AND CONCLUSIONS: The recommendations were developed to guide physicians in optimal practices in patient selection for enfuvirtide treatment and subsequent patient management. The issues considered include positive predictors of response to enfuvirtide, stage of disease, optimization of the background regimen, early indicators of enfuvirtide response, and patient education and support. 相似文献
9.
R F Rossi R Ekroth K Jansson M Scallan R J Thompson C Lincoln 《Scandinavian journal of thoracic and cardiovascular surgery》1990,24(1):75-77
The concentration of brain type creatine kinase (CK-BB) was measured in blood from the internal jugular vein in 32 children (less than 1 year old) with congenital heart disease. In transposition of the great arteries the CK-BB levels were significantly higher than in children without cyanosis (10.1 +/- 4.1 vs. 3.0 +/- 0.5 ng/ml). A negative correlation was found for CK-BB concentration and arterial oxygen saturation (r = -0.41, p less than 0.02 for all children and r = -0.62, p less than 0.05 for those with tetralogy of Fallot). It is suggested that the increased CK-BB levels in the blood of cyanotic children reflect chronic cerebral hypoxia, which may explain other reports of reduced psycho-intellectual function in patients with cyanotic heart disease. 相似文献
10.
Christopher R Pryce Andrea C Dettling Marianne Spengler Christian R Schnell Joram Feldon 《Neuropsychopharmacology》2004,56(2):72-79
BACKGROUND: Early environment is a major determinant of long-term mental health, evidenced by the relationship between early-life neglect or abuse and chronically increased vulnerability to developmental psychopathology, including major depressive disorder (MDD). Animal studies can increase understanding of environmentally mediated causal risk processes. We describe how daily deprivation of biological parenting in primate infants disrupts development of homeostatic and reward systems central to MDD. METHODS: Nine breeding pairs of marmoset monkeys provided control twins (CON) and early-deprived twins (ED); the latter were socially isolated for 30-120 min/day on days 2-28. During the first year of life, basal urinary norepinephrine (NE) titers and cardiophysiologic activity were measured. At the end of year 1 (adolescence), automated neuropsychologic tests were conducted to measure responsiveness to changes in stimulus-reward association (simple/reversed visual discrimination learning) and to reward per se (progressive ratio [PR] reinforcement schedule). RESULTS: The ED monkeys exhibited increased basal urinary NE titers and increased systolic blood pressure relative to CON siblings. The ED monkeys required more sessions to reinstate stimulus-oriented behavior following reversal, suggesting increased vulnerability to perceived loss of environmental control; ED monkeys also performed less PR operant responses, indicating that reward was less of an incentive and that they were mildly anhedonic relative to CON. CONCLUSIONS: In marmoset monkeys, neglect-like manipulation of ED leads to chronic changes in homeostatic systems, similar to those in children and adolescents exposed to early-life adversity and in MDD, and to responses to environmental stimuli similar to those that characterize MDD. 相似文献