全文获取类型
收费全文 | 1286711篇 |
免费 | 91524篇 |
国内免费 | 9693篇 |
专业分类
耳鼻咽喉 | 17934篇 |
儿科学 | 32209篇 |
妇产科学 | 32616篇 |
基础医学 | 181754篇 |
口腔科学 | 37969篇 |
临床医学 | 115783篇 |
内科学 | 248905篇 |
皮肤病学 | 26080篇 |
神经病学 | 96601篇 |
特种医学 | 48916篇 |
外国民族医学 | 202篇 |
外科学 | 200901篇 |
综合类 | 40556篇 |
现状与发展 | 25篇 |
一般理论 | 305篇 |
预防医学 | 80499篇 |
眼科学 | 31467篇 |
药学 | 103694篇 |
60篇 | |
中国医学 | 8665篇 |
肿瘤学 | 82787篇 |
出版年
2021年 | 12618篇 |
2019年 | 11275篇 |
2018年 | 15818篇 |
2017年 | 12490篇 |
2016年 | 13226篇 |
2015年 | 16116篇 |
2014年 | 21753篇 |
2013年 | 28047篇 |
2012年 | 39117篇 |
2011年 | 41035篇 |
2010年 | 24395篇 |
2009年 | 22403篇 |
2008年 | 36697篇 |
2007年 | 38883篇 |
2006年 | 39163篇 |
2005年 | 37819篇 |
2004年 | 34727篇 |
2003年 | 33055篇 |
2002年 | 31942篇 |
2001年 | 73848篇 |
2000年 | 75943篇 |
1999年 | 63563篇 |
1998年 | 15889篇 |
1997年 | 13849篇 |
1996年 | 13391篇 |
1995年 | 12465篇 |
1994年 | 11321篇 |
1993年 | 10189篇 |
1992年 | 46087篇 |
1991年 | 43589篇 |
1990年 | 41821篇 |
1989年 | 40871篇 |
1988年 | 37086篇 |
1987年 | 36066篇 |
1986年 | 33544篇 |
1985年 | 31763篇 |
1984年 | 22416篇 |
1983年 | 18855篇 |
1982年 | 9737篇 |
1979年 | 19553篇 |
1978年 | 13002篇 |
1977年 | 11203篇 |
1976年 | 9564篇 |
1975年 | 10534篇 |
1974年 | 12724篇 |
1973年 | 11974篇 |
1972年 | 11417篇 |
1971年 | 10906篇 |
1970年 | 10266篇 |
1969年 | 9713篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
31.
32.
AIM: The intention was to investigate cerebrospinal fluid pressure (CSFP) and volume of cerebrospinal fluid (CSF) drained during and after thoracic- and thoracoabdominal aneurysm repair. The findings were related to the occurrence of postoperative neurologic deficits. METHODS: Twenty-nine patients (12 with thoracic and 17 with thoracoabdominal aortic aneurysm) were operated without shunting or extracorporeal circulation. For monitoring of CSFP an intrathecal catheter was placed in all patients. The volume of CSF withdrawn intraoperatively, on the day of operation as well as on the 1st and 2nd postoperative day was recorded. RESULTS: Twenty-six patients had no postoperative neurologic sequelae. One patient had postoperative paraplegia while 2 had paraparesis. The three patients with neurologic sequelae had higher CSFP intraoperatively than those without neurologic symptoms (P=0.04). Median CSFP during aortic cross-clamping was 19 mmHg and 10 mmHg and the median volumes of CSF drained on the day of operation 210 and 85 mL in the two groups, respectively. There was a significant positive correlation between CSFP and central venous pressure. CONCLUSIONS: A higher intraoperative CSFP was observed in patients with neurologic sequelae following thoracic- and thoracoabdominal aneurysm repair. Further, there was a tendency of higher volumes of CSF drained in this group of patients. Although, the series is too small to allow firm conclusions, it supports the view that CSFP monitoring and drainage is beneficial during thoracic- and thoracoabdominal aneurysm repair. 相似文献
33.
34.
35.
36.
S Balzer D T Schneider M B Bernbeck M J?ger O Mils J Schaper R Willers R Krauspe U G?bel R Wessalowski 《International journal of hyperthermia》2006,22(6):451-461
PURPOSE: In children with locally advanced or recurrent malignant tumours, prognosis can be improved by regional deep hyperthermia (RHT) in combination with platin-based chemotherapy. However, because of the increasing number of patients that achieve long-time remission with this therapy, it is necessary to evaluate long-term sequelae of thermochemotherapy. During the years 1993-2004 one has observed avascular osteonecrosis (AON) of the femoral head after RHT in seven children with pelvic germ cell tumours or rhabdomyosarcomas. METHODS: Although AON may develop in patients with malignancies treated with chemo- or radiotherapy alone, RHT might nevertheless contribute to the occurrence of AON. In order to determine potential risk factors for AON after RHT, this study analysed the relationship of AON to the patient's age, medical history and treatment parameters such as thermal dose equivalent and power output. RESULTS AND CONCLUSIONS: In the present study AON was associated with young age as well as intensity of hyperthermia indicated by high power levels that exceed 20 W per kg body weight and/or application of eight or more heat sessions as well as additional radiotherapy. Based on this observation, it was assumed that an optimized three dimensional thermal field modelling may be helpful to avoid hazardous temperatures in the femoral heads during RHT treatment and to reduce AON of the femoral heads. 相似文献
37.
S F Wong A Lee-Tannock D Amaraddio F Y Chan H D McIntyre 《Ultrasound in obstetrics & gynecology》2006,28(7):934-938
OBJECTIVE: To assess the effect of glucose control on the rate of growth of fetuses in women with pregestational diabetes mellitus (Types 1 and 2). METHODS: All pregestational diabetic women booked at Mater Mothers' Hospital, Brisbane, Australia, between 1 January 1994 and 31 December 2002, were included. Pregnancies with congenital fetal anomalies, multiple pregnancies, and pregnancies terminated prior to 20 weeks' gestation were excluded. Dating scans were performed before 14 weeks' gestation and serial scans were performed at 18, 24, 28, 32 and 36 weeks. Fetal parameters, including biparietal diameter, femur length and abdominal circumference, were recorded. The daily growth rates for biparietal diameter, femur length, and fetal abdominal area were calculated and compared with those in a low-risk (non-diabetic) population. The growth rates in fetuses of women with satisfactory diabetic control (HbA1c < 6.5%) and unsatisfactory control (HbA1c > or = 6.5%) in the three trimesters were compared. RESULTS: A total of 174 diabetic pregnancies were included and a total of 997 ultrasound scans were performed. The growth rates for fetuses of mothers with diabetes mellitus were significantly higher than for those in the low-risk population. The z-scores for biparietal diameter, femur length, and fetal abdominal area were 0.18, 0.59 and 1.44, respectively. Fetuses of diabetic mothers with high HbA1c in the first trimester had significantly greater fetal abdominal area growth rate than those with normal HbA1c (fetal abdominal area z-score of 1.7 vs. 0.75, P = 0.009). Although the fetal abdominal area z-scores in fetuses of diabetic mothers with high HbA1c in the second or third trimesters were also higher than those with normal HbA1c levels, the differences did not reach statistical significance. Maternal obesity did not influence the fetal growth rate. CONCLUSION: The rate of growth of fetuses of diabetic mothers differs from that of the normal population. Growth acceleration persists until the late third trimester. Moreover, periconceptional glucose control appears to have a significant effect on accelerated growth of the fetal abdominal area. 相似文献
38.
Published data devoted to making and characterization of the properties of polymeric wound dressings with proteolytic action
are reviewed. These data are indicative of individual dependence of the physicochemical properties, activity, and stability
of each particular enzyme on the type of polymer matrix and the method of immobilization. In order to obtain wound dressings,
which are active in physiological medium and retain their activity upon sterilization, it is necessary to optimize the composition
and characteristics of a polymer matrix and the enzyme included into its structure.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 40, No. 8, pp. 24–28, August, 2006. 相似文献
39.
Ohne Zusammenfassung 相似文献
40.
F Pitta T Troosters V S Probst M A Spruit M Decramer R Gosselink 《The European respiratory journal》2006,27(5):1040-1055
Accurate assessment of the amount and intensity of physical activity in daily life is considered very important due to the close relationship between physical activity level, health, disability and mortality. For this reason, assessment of physical activity in daily life has gained interest in recent years, especially in sedentary populations, such as patients with chronic obstructive pulmonary disease (COPD). The present article aims to compare and discuss the two kinds of instruments more commonly used to quantify the amount of physical activity performed by COPD patients in daily life: subjective methods (questionnaires, diaries) and motion sensors (electronic or mechanical methods). Their characteristics are summarised and evidence of their validity, reliability and sensitivity is discussed, when available. Subjective methods have practical value mainly in providing the patients' view on their performance in activities of daily living and functional status. However, care must be taken when using subjective methods to accurately quantify the amount of daily physical activity performed. More accurate information is likely to be available with motion sensors rather than questionnaires. The selection of which motion sensor to use for quantification of physical activity in daily life should depend mainly on the purpose of its use. 相似文献