全文获取类型
收费全文 | 2506篇 |
免费 | 279篇 |
国内免费 | 21篇 |
专业分类
耳鼻咽喉 | 45篇 |
儿科学 | 68篇 |
妇产科学 | 61篇 |
基础医学 | 154篇 |
口腔科学 | 139篇 |
临床医学 | 314篇 |
内科学 | 659篇 |
皮肤病学 | 47篇 |
神经病学 | 101篇 |
特种医学 | 301篇 |
外科学 | 211篇 |
综合类 | 35篇 |
预防医学 | 363篇 |
眼科学 | 17篇 |
药学 | 173篇 |
中国医学 | 1篇 |
肿瘤学 | 117篇 |
出版年
2023年 | 49篇 |
2022年 | 15篇 |
2021年 | 18篇 |
2020年 | 49篇 |
2019年 | 31篇 |
2018年 | 65篇 |
2017年 | 38篇 |
2016年 | 47篇 |
2015年 | 61篇 |
2014年 | 112篇 |
2013年 | 135篇 |
2012年 | 59篇 |
2011年 | 77篇 |
2010年 | 76篇 |
2009年 | 94篇 |
2008年 | 71篇 |
2007年 | 111篇 |
2006年 | 98篇 |
2005年 | 90篇 |
2004年 | 93篇 |
2003年 | 57篇 |
2002年 | 56篇 |
2001年 | 66篇 |
2000年 | 73篇 |
1999年 | 73篇 |
1998年 | 74篇 |
1997年 | 101篇 |
1996年 | 88篇 |
1995年 | 66篇 |
1994年 | 70篇 |
1993年 | 60篇 |
1992年 | 35篇 |
1991年 | 32篇 |
1990年 | 48篇 |
1989年 | 59篇 |
1988年 | 49篇 |
1987年 | 59篇 |
1986年 | 48篇 |
1985年 | 48篇 |
1984年 | 33篇 |
1983年 | 19篇 |
1982年 | 31篇 |
1981年 | 33篇 |
1980年 | 26篇 |
1979年 | 17篇 |
1978年 | 12篇 |
1977年 | 15篇 |
1976年 | 20篇 |
1975年 | 13篇 |
1974年 | 10篇 |
排序方式: 共有2806条查询结果,搜索用时 0 毫秒
1.
Lisa A. Lang DDS MS David C. Holmes DDS MS Craig Passon DDS MS Robert M. Trombly DDS JD Jeffrey D. Astroth DDS MSPH Arnold F. Tavel DMD 《Journal of prosthodontics》2003,12(3):206-210
Using complete denture treatment as an introduction to clinical patient care for dental students, the purposes of the Complete Denture Prosthodontics Transition Clinic at the University of Colorado School of Dentistry are to reduce the time lapse between the preclinical complete denture prosthodontics course and the first denture patient experience, and to encourage development of student self-confidence and skills. In the 2002 spring semester, faculty at the University of Colorado School of Dentistry initiated the Complete Denture Prosthodontics Transition Clinic for DS-II (second-year) dental students, as an introduction to clinical patient care. Each patient was assigned to a team of two dental students. Three Division of Prosthodontics faculty members staffed each clinic session, providing a student-to-faculty ratio of approximately 6.6:1 and a patient-to-faculty ratio of approximately 3.3:1. All DS-II students in the Class of 2004 delivered their first complete dentures no later than 8 months (average, 184 days) after the last day of the preclinical complete denture prosthodontics course. The time from the diagnostic appointment through the denture placement appointment averaged 39 days for patients treated in this program, compared with an average of 98 days or more for previous classes. The program was successful in achieving the goal of reducing the time lapse between the preclinical complete denture prosthodontics course and the first denture patient experience. 相似文献
2.
Maren T Scheuner William C Whitworth Henraya McGruder Paula W Yoon Muin J Khoury 《Genetics in medicine》2006,8(8):525-531
PURPOSE: We examined the performance of a familial risk assessment method that stratifies risk for early-onset coronary heart disease by considering the number of relatives with coronary disease, degree of relationship, lineage, and age at diagnosis. METHODS: By using data from the HealthStyles 2003 survey, we assessed the associations between familial risk and early-onset coronary heart disease, diabetes, hypercholesterolemia, hypertension, and obesity. By using area under the curve statistics, we evaluated the discriminatory ability of various risk assessment models. RESULTS: Of 4,035 respondents, 60% were female and 72% were white, with a mean age of 48.8 years. After adjustment for demographics, strong and moderate risk were significantly associated with approximately a five- and twofold risk of early-onset coronary disease, respectively. After adjustment for demographics and personal history of cardiovascular disease, strong familial risk was also significantly associated with diabetes, hypercholesterolemia, hypertension, and obesity. A risk assessment model that included familial risk, demographics, and personal history of diabetes, hypercholesterolemia, hypertension, and obesity was most optimal with an area under the curve statistic of 87.2% CONCLUSIONS: Familial risk assessment can stratify risk for early-onset coronary heart disease. Several conditions associated with increased familial risk can be prevented. These results have important implications for risk assessment and risk-reducing interventions. 相似文献
3.
Peter B. Richman MD Shari Dominguez MD David Kasper MD Frederick Chen MD Jeremy Friese MD Joseph Wood MD JD Joseph Collins MD Jeffrey A. Kline MD 《Academic emergency medicine》2006,13(3):295-301
Objectives: To determine interobserver agreement between radiologists for computed tomography (CT) angiography and venography. CT venography of the lower extremities combined with standard CT angiography of the chest may result in an increased overall diagnosis rate of venous thromboembolism (pulmonary embolism or deep venous thrombosis).
Methods: The study had a retrospective cohort design. The population consisted of emergency department patients who were evaluated for suspected pulmonary embolism. A random sample of 50 patients diagnosed and treated for venous thromboembolism and 50 age- and gender-matched patients whose CT angiograms and venograms were read as negative were enrolled. The original reading (R1) was compared with readings of two study radiologists: R2, a general radiologist, and R3, a radiologist with fellowship training in cross-sectional imaging. All readers were blinded to each other.
Results: Both R2 and R3 found both CT angiogram and venogram components technically adequate in 95% (95% CI = 89% to 98%) and 86% (95% CI = 78% to 92%) of studies, respectively. The agreement was very good for CT angiography (lowest agreement = 92%; lowest κ = 0.83) and was good for CT venography (85%, κ = 0.65). In nine cases, R1 read the CT angiogram as negative but the venogram as positive for DVT, whereas both R2 and R3 read both components as negative in four of these nine, suggesting a false-positive isolated DVT rate of 44% (95% CI = 19% to 73%). In no case did R1 read both scan components as negative when R2 and R3 agreed on presence of pulmonary embolism or DVT.
Conclusions: Diagnosis of pulmonary embolism on CT angiography is more reliable than diagnosis of isolated DVT on CT venography. 相似文献
Methods: The study had a retrospective cohort design. The population consisted of emergency department patients who were evaluated for suspected pulmonary embolism. A random sample of 50 patients diagnosed and treated for venous thromboembolism and 50 age- and gender-matched patients whose CT angiograms and venograms were read as negative were enrolled. The original reading (R1) was compared with readings of two study radiologists: R2, a general radiologist, and R3, a radiologist with fellowship training in cross-sectional imaging. All readers were blinded to each other.
Results: Both R2 and R3 found both CT angiogram and venogram components technically adequate in 95% (95% CI = 89% to 98%) and 86% (95% CI = 78% to 92%) of studies, respectively. The agreement was very good for CT angiography (lowest agreement = 92%; lowest κ = 0.83) and was good for CT venography (85%, κ = 0.65). In nine cases, R1 read the CT angiogram as negative but the venogram as positive for DVT, whereas both R2 and R3 read both components as negative in four of these nine, suggesting a false-positive isolated DVT rate of 44% (95% CI = 19% to 73%). In no case did R1 read both scan components as negative when R2 and R3 agreed on presence of pulmonary embolism or DVT.
Conclusions: Diagnosis of pulmonary embolism on CT angiography is more reliable than diagnosis of isolated DVT on CT venography. 相似文献
4.
Müllerian duct regression is first apparent in male pouch young of the tammar wallaby (Macropus eugenii) 6–7 days after birth and, as in eutherian mammals, is characterised by a condensation of the periductal mesenchyme into
a whorl around the ductal epithelial cells. A decrease in the density of the extracellular matrix was observed in the region
of the whorl. In contrast to eutherian mammals no changes were observed in the mean outer diameter of the Müllerian duct during
the early stages of regression. The time at which these mesenchymal changes occur corresponds to the period of Müllerian inhibiting
substance secretion in the postnatal tammar testis.
Accepted: 25 February 1997 相似文献
5.
6.
Benign intracranial hypertension and recombinant growth hormone therapy in Australia and New Zealand
PA Crock JD McKenzie AM Nicoll NJ Howard W Cutfield LK Shield G Byrne 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(4):381-386
Benign intracranial hypertension (BIH) is reported in three children from Australia and one from New Zealand, who were being treated with recombinant human growth hormone (rhGH). Three males and one female, aged between 10.5 and 14.2 y, developed intracranial hypertension within 2 weeks to 3 months of starting treatment. A national database, OZGROW, has been prospectively collecting data on all 3332 children treated with rhGH in Australia and New Zealand from January 1986 to 1996. The incidence of BIH in children treated with growth hormone (GH) is small, 1.2 per 1000 cases overall, but appears to be greater with biochemical GHD (<10IUml -1 ), i.e. 6.5/1000 (3 in 465 cases), relative risk 18.4, 95% confidence interval 1.9-176.1, than in all other children on the database. The incidence in patients with Turner's syndrome was 2.3/1000 (1 in 428 cases). No cases in patients with partial GHD (10–20 IUml -1 ) or chronic renal failure were identified. Possible causative mechanisms are discussed. The authors'practice is now to start GH replacement at less than the usual recommended dose of 14IUm-2 week-1 in those children considered to be at high risk of developing BIH. Ophthalmological evaluation is recommended for children before and during the first few months following commencement of rhGH therapy and is mandatory in the event of peripheral or facial oedema, persistent headaches, vomiting or visual symptoms. The absence of papilledema does not exclude the diagnosis. 相似文献
7.
Milton J. Guiberteau MD Pamela A. Wilcox RN MBA Sandra Bjork RN JD 《Journal of the American College of Radiology》2004,1(2):92-97
Clinical practice guidelines have emerged as a reality for medical practitioners over the past 20 years. Although virtually all groups interested in the development of practice guidelines hope for improvements in patient care, secondary expectations vary widely among those using them. Their use in daily practice by physicians has met with resistance from barriers including concerns of “cookbook” medicine, a loss of autonomy, and increased professional liability. The recent experience of the ACR in addressing these challenges illustrates that physicians are receptive to steps perceived to mitigate the risks accompanying the use of guidelines as well as to efforts to increase their understanding of implementing guidelines in clinical practice. The experiences of other medical societies and an inventory of future trends reveal additional challenges associated with the use of practice guidelines, as third parties look to guidelines as points of reference for gauging the performance of health care providers. 相似文献
8.
目的由于卒中风险随着狭窄严重程度的增加而升高,因此认为颈内动脉(ICA)接近闭塞患者的卒中风险很高。在现有的随机试验中,还没有专门针对这种情况进行探讨,因此其处理尚存在争汶。方法:对相关文献进行系统评价。结果:对ICA接近闭塞患者的处理还存在争议:一些学者支持进行干预,而另一些学者则认为存在风险或没有益处而反对进行干预。在ICA接近闭塞的有症状患者中进行一项比较外科治疗与最佳内科治疗的多中心前瞻性随机试验似乎非常困难,因为这类研究需要大量的患者。尽管如此,基于目前的证据,似乎很难拒绝手术治疗。结论:由于目前对ICA接近闭塞患者的最佳处理方案仍存在着争议,因此需要前瞻性观察性研究以证实其在有症状和无症状人群中的患病率以及相关的卒中风险。基于目前的证据,大多数医疗中心选择手术治疗,但它相对干内科治疗的特粱尚右待证章. 相似文献
9.
Neuropsychological assessment, neuroimaging, and neuropsychiatric evaluation in pediatric and adult patients with sickle cell disease (SCD) 下载免费PDF全文
Christopher L Edwards Renee Dunn Raynor Miriam Feliu Camela McDougald Stephanie Johnson Donald Schmechel Mary Wood Gary G Bennett Patrick Saurona Melanie Bonner Chante Wellington Laura M DeCastro Elaine Whitworth Mary Abrams Patrick Logue Lekisha Edwards Salutario Martinez Keith E Whitfield 《Neuropsychiatric Disease and Treatment》2007,3(6):705-709
Traditionally, neuropsychological deficits due to Sickle Cell Disease (SCD) have been understudied in adults. We have begun to suspect, however, that symptomatic and asymptomatic Cerebrovascular Events (CVE) may account for an alarming number of deficits in this population. In the current brief review, we critically evaluated the pediatric and adult literatures on the neurocognitive effects of SCD. We highlighted the studies that have been published on this topic and posit that early detection of CVE via neurocognitive testing, neuropsychiatric evaluations, and neuroimaging may significantly reduce adult cognitive and functional morbidities. 相似文献
10.
C H Stuppaeck R Pycha C Miller A B Whitworth H Oberbauer W W Fleischhacker 《Alcohol and alcoholism (Oxford, Oxfordshire)》1992,27(2):153-158
The use of more than 130 drugs and drug combinations against the alcohol withdrawal syndrome reflects the fact that views on its treatment are far from being unequivocal. Benzodiazepines are the first choice treatment but it should not be disregarded that they have side effects and, above all, a varying risk of dependency themselves. In recent years many trials have focused on carbamazepine in this respect. Its efficacy was proven in various open and double-blind studies, most of them using concomitant sedative drugs, thereby diminishing the reliability of the results. In a double-blind study we compared the efficacy of carbamazepine with that of oxazepam, in 60 in-patients suffering from alcohol withdrawal syndrome. The main rating instrument was the Clinical Institute Withdrawal Scale--Alcohol (CIWA-A). The 7-day trial showed equal efficacy of carbamazepine and oxazepam during the first 5 days and a statistically significant superiority of carbamazepine on days 6 and 7. Four patients in each group had to be dropped from the study due to side effects or after having withdrawn informed consent. There was no decrease in white blood counts under carbamazepine. The experiences with carbamazepine up to now suggest a more widespread use, especially in non-delirious withdrawal states. 相似文献