全文获取类型
收费全文 | 1088篇 |
免费 | 96篇 |
国内免费 | 7篇 |
专业分类
耳鼻咽喉 | 8篇 |
儿科学 | 138篇 |
妇产科学 | 14篇 |
基础医学 | 163篇 |
口腔科学 | 11篇 |
临床医学 | 67篇 |
内科学 | 203篇 |
皮肤病学 | 15篇 |
神经病学 | 28篇 |
特种医学 | 93篇 |
外科学 | 219篇 |
综合类 | 88篇 |
预防医学 | 52篇 |
眼科学 | 31篇 |
药学 | 22篇 |
中国医学 | 2篇 |
肿瘤学 | 37篇 |
出版年
2022年 | 12篇 |
2021年 | 11篇 |
2020年 | 8篇 |
2019年 | 7篇 |
2018年 | 14篇 |
2017年 | 9篇 |
2016年 | 17篇 |
2015年 | 23篇 |
2014年 | 14篇 |
2013年 | 16篇 |
2012年 | 35篇 |
2011年 | 35篇 |
2010年 | 34篇 |
2009年 | 24篇 |
2008年 | 44篇 |
2007年 | 46篇 |
2006年 | 53篇 |
2005年 | 49篇 |
2004年 | 65篇 |
2003年 | 27篇 |
2002年 | 46篇 |
2001年 | 40篇 |
2000年 | 36篇 |
1999年 | 27篇 |
1998年 | 40篇 |
1997年 | 35篇 |
1996年 | 26篇 |
1995年 | 22篇 |
1994年 | 24篇 |
1993年 | 14篇 |
1992年 | 16篇 |
1991年 | 27篇 |
1990年 | 24篇 |
1989年 | 32篇 |
1988年 | 34篇 |
1987年 | 27篇 |
1986年 | 25篇 |
1985年 | 20篇 |
1984年 | 18篇 |
1983年 | 22篇 |
1982年 | 20篇 |
1981年 | 15篇 |
1980年 | 11篇 |
1979年 | 3篇 |
1978年 | 7篇 |
1977年 | 3篇 |
1976年 | 7篇 |
1975年 | 11篇 |
1974年 | 4篇 |
1971年 | 5篇 |
排序方式: 共有1191条查询结果,搜索用时 15 毫秒
61.
62.
The extra-skeletal effects of vitamin D have been increasingly recognized in the recent years and its effects on blood pressure
and cardiac function are areas of active investigation. This article reviews the current state of knowledge about vitamin
D with respect to blood pressure and left ventricular hypertrophy. Potential biological mechanisms implicated in linking vitamin
D deficiency with hypertension and cardiac dysfunction are outlined along with data from both observational and randomized
controlled trials on this topic. 相似文献
63.
Francesco Casella M.D. Bushra Rana M.D. Giovanni Casazza Ph.D. † Amit Bhan M.D. Stam Kapetanakis M.D. Joe Omigie Joseph Reiken Mark J. Monaghan M.Sc. Ph.D. 《Echocardiography (Mount Kisco, N.Y.)》2009,26(8):900-906
Background: Between 1987 and 1994, several studies demostrated transthoracic echocardiography (TTE) to be less sensitive than transesophageal echocardiography (TEE) in detecting native valve endocarditis. Recent technologic advances, especially the introduction of harmonic imaging and digital processing and storage, have improved TTE image quality. The aim of this study was to determine the diagnostic accuracy of contemporary TTE. Methods: Between 2003 and 2007, 75 patients underwent both TTE and TEE for clinically suspected infective endocarditis. The diagnostic accuracy of TTE was assessed using transesophageal echocardiography as the gold standard for diagnosis of endocarditis. Results: Of the 75 patients in this study, 33 were found to be positive by TEE. The sensitivity for detection of infective endocarditis by TTE was 81.8%. It provided good image quality in 81.5% of cases; in these patients sensitivity was even greater (89.3%). Conclusion: Contemporary TTE has improved the diagnostic accuracy of infective endocarditis by ameliorating image quality; it provides an accurate assessment of endocarditis and may reduce the need for TEE. 相似文献
64.
We describe the case of a 40‐year‐old woman who presented with a pararenal hyaline‐vascular type Castleman’s disease that had an arterial supply from the renal artery and a draining vein as showed by multidetector CT. Identification of the renal artery relationship to the feeding vessel of the mass is critical to prevent potential surgical complications. 相似文献
65.
66.
T H Bourne M I Whitehead S Campbell P Royston V Bhan W P Collins 《Gynecologic oncology》1991,43(2):92-97
We have used transvaginal ultrasonography to screen 776 asymptomatic women for familial ovarian cancer. Every woman had at least one first- or second-degree relative develop the disease (677, 87%; and 98, 13%, respectively). The mean age of the study population was 51 years (range, 24 to 78 years); 52% were premenopausal, 36% were naturally postmenopausal, and 12% had undergone a hysterectomy. Overall, 43 women (5.5%) were referred for surgical investigation and 39 had a laparatomy. Nineteen/thirty-nine (48%) had bilateral ovarian masses, and 15% of abnormal ovaries had more than one type of histopathology. Twenty-three tumors and thirty-two tumor-like conditions were detected. There were 3 cases of primary ovarian cancer (prevalence, 3.9/1000), all FIGO stage Ia. None of the women has developed ovarian cancer within the first year of the scan (giving a provisional detection rate of 100%). The false positive rate was 40/773 (5.2%), the predictive value of a positive screen result was 7.7%, and the odds in favor of finding any mass at laparotomy were about 19 to 1 or for any tumor, 1 to 1. At surgery the odds against finding primary ovarian cancer were 12 to 1. The positive predictive value of the screening procedure and the prevalence of the disease were significantly higher than the corresponding values from a previous population-based screening program. 相似文献
67.
V Bhan N Amso M I Whitehead S Campbell P Royston W P Collins 《British journal of obstetrics and gynaecology》1989,96(12):1384-1391
Persistent ovarian masses have been found in a substantial proportion of 5479 self-selected asymptomatic women who were screened for early ovarian neoplasia. Each woman was scheduled to undergo three ultrasound screens (consisting of 1-12 scans) to detect regressing and non-regressing masses. A total of 14,594 screens (15,977 scans) was performed. The average interval between successive screens was 595 days (range 214-1134 days). Overall, 650 screens (4.4%; 10.1% of women) produced a positive result which became negative with successive scans (four times more frequently in pre- than naturally postmenopausal women), and 338 screens (2.3%; 5.9% of women) had a final positive result (at least one ovary that was grossly abnormal or contained a persistent mass). Biopsies were taken from 336 ovaries (89% of total, 271 women). Overall, 134 tumour-like conditions and 119 benign tumours were identified. The detection rate of tumour-like conditions was 1.5 times higher in premenopausal than naturally postmenopausal women, whereas the proportion of tumours to normal ovaries was similar in both groups. Overall, 51% of tumour-like conditions and 70% of all tumours were detected at screen 1. Four women had metastatic ovarian cancer (three at screen 1, one at screen 2; two were bilateral). Five women (0.1%) had a primary malignant tumour (two at screen 1, three at screen 2; four were stage 1a and one was stage 1b). All women are being monitored to obtain additional information about the significance of the findings. 相似文献
68.
SK Bhattacharya MK Bhattacharya B Manna D Dutta A Deb P Dutta AG Goswami A Dutta S Sarkar A Mukhopadhaya T Krishnan TN Naik GB Nair 《Acta paediatrica (Oslo, Norway : 1992)》1995,84(2):160-164
In a case-control study to understand the risk factors for development of life-threatening dehydration, a total of 379 children comprising 243 cases (moderate or severe dehydration) and 136 controls (non or mild dehydration) up to 2 years of age suffering from acute watery diarrhoea were studied. By univariate analysis, the presence of vibrios in stool, withdrawal of breast feeding during diarrhoea, not giving fluids, including oral rehydration solution (ORS), during diarrhoea, frequent purging (> 8/ day), vomiting (> 2/day) and undernutrition were identified as risk factors. However, by multivariate analysis after controlling for confounders, withdrawal of breast feeding during diarrhoea (odds ratio (OR) = 6.8, p < 0.00001) and not giving ORS during diarrhoea (OR = 2.1, p < 0.006) were identified as significant risk factors. The confounding variables which also contributed significantly to increasing the risk were age (≤ 12 months; OR = 2.7, p = 0.001), frequent purging (> 8/day; OR = 4.1, p < 0.00001), vomiting (> 2/day; OR = 2.4, p = 0.001) and severe undernutrition (%median <60 weight-for-age of Indian Academy of Paediatrics classification; OR = 3.1, p = 0.001). We feel that these findings will be useful for Global and National Diarrhoeal Diseases Control Programmes for formulating intervention strategies for preventing death due to diarrhoeal dehydration. 相似文献
69.
V Khoshoo M K Bhan N K Arora D Sood R Kumar G Stintzing 《Acta paediatrica Scandinavica》1986,75(2):308-312
The leucocyte migration inhibition (LMI) was determined in an assay after in vitro challenge with beta-lactoglobulin. The assay was considered positive when migration inhibition index was greater than 20% (mean +3 SD of healthy infants). Ninety-eight infants with protracted diarrhoea and failure to thrive, 16 healthy, 12 malnourished, and 16 infants suffering from acute gastroenteritis were studied. Of the 98 patients with protracted diarrhoea, 12 fulfilled Goldman's criteria for cow's milk protein intolerance, 63 had lactose malabsorption, and in 15 no associated causative factor was identified. The mean index of migration inhibition in the cow's milk allergic group (58.83 +/- 11.98) was higher than in healthy controls (8.25 +/- 3.91), the difference being statistically significant (p less than 0.05). The test was positive in all patients with cow's milk protein intolerance. The assay was also positive in four other patients suffering from protracted diarrhoea, two of whom had lactose malabsorption. All the infants with acute gastroenteritis and malnutrition had values within the normal range. The migration inhibition index in five patients with cow's milk intolerance had declined to 24.74 +/- 4.87 in assays performed 1-6 weeks after return of clinical tolerance to cow's milk (p less than 0.05) but the test was still within the positive range in three of the five infants. These results suggest that this cell mediated immune assay is a sensitive test for the diagnosis of cow's milk protein intolerance in infants. The specificity needs to be reassessed in the light of more objective criteria for the diagnosis of cow's milk protein intolerance. 相似文献
70.
Durairaj M Sharma R Choudhary SK Bhan A Venugopal P 《The Annals of thoracic surgery》2002,74(3):931-932
A 12-year-old child with chronic pleural effusions for a month and a half after a fenestrated Fontan operation underwent bilateral diaphragmatic fenestrations with complete relief. We suggest this approach as an alternative treatment for chronic pleural effusions that may ensue after total cavopulmonary connection. 相似文献