全文获取类型
收费全文 | 3270篇 |
免费 | 269篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 38篇 |
儿科学 | 91篇 |
妇产科学 | 57篇 |
基础医学 | 452篇 |
口腔科学 | 49篇 |
临床医学 | 484篇 |
内科学 | 642篇 |
皮肤病学 | 22篇 |
神经病学 | 387篇 |
特种医学 | 71篇 |
外科学 | 327篇 |
综合类 | 42篇 |
一般理论 | 2篇 |
预防医学 | 396篇 |
眼科学 | 31篇 |
药学 | 202篇 |
中国医学 | 6篇 |
肿瘤学 | 246篇 |
出版年
2023年 | 51篇 |
2022年 | 28篇 |
2021年 | 101篇 |
2020年 | 68篇 |
2019年 | 104篇 |
2018年 | 116篇 |
2017年 | 73篇 |
2016年 | 68篇 |
2015年 | 90篇 |
2014年 | 117篇 |
2013年 | 120篇 |
2012年 | 245篇 |
2011年 | 235篇 |
2010年 | 104篇 |
2009年 | 83篇 |
2008年 | 172篇 |
2007年 | 175篇 |
2006年 | 162篇 |
2005年 | 193篇 |
2004年 | 178篇 |
2003年 | 149篇 |
2002年 | 135篇 |
2001年 | 46篇 |
2000年 | 39篇 |
1999年 | 50篇 |
1998年 | 31篇 |
1997年 | 21篇 |
1996年 | 18篇 |
1995年 | 25篇 |
1994年 | 21篇 |
1993年 | 22篇 |
1992年 | 42篇 |
1991年 | 35篇 |
1990年 | 38篇 |
1989年 | 32篇 |
1988年 | 32篇 |
1987年 | 14篇 |
1986年 | 19篇 |
1985年 | 24篇 |
1984年 | 15篇 |
1980年 | 16篇 |
1979年 | 17篇 |
1977年 | 13篇 |
1976年 | 15篇 |
1973年 | 15篇 |
1972年 | 15篇 |
1971年 | 17篇 |
1970年 | 18篇 |
1969年 | 15篇 |
1966年 | 13篇 |
排序方式: 共有3545条查询结果,搜索用时 0 毫秒
1.
Paula Cristina Galati Paula Garcia Chiarello Belinda Pinto Simões 《Nutrition and cancer》2016,68(1):86-93
Changes in resting energy expenditure (REE) of cancer patients vary depending on type of tumor, treatment time point and kind of treatment. Little is known about REE of acute leukemia adult patients after treatment, especially with results related to body weight or fat free mass (FFM). This study aimed to assess changes in REE of acute leukemia adult patients before and after the first remission induction. Evaluation of REE was performed by indirect calorimetry and predicted REE was calculated by Harris-Benedict equation. Weight and height were measured and compared to a control group of healthy individuals. FFM was assessed by bioelectrical impedance for adjusting REE values. We evaluated 18 patients and 26 healthy individuals. At diagnosis, patients presented REE, REE/weight, and REE/FFM higher than the controls. Reductions of REE, REE/weight, and REE/FFM were also observed in patients after the first cycle of chemotherapy. The predicted REE for the patients group showed significant lower value compared with measured REE. Before the first cycle of chemotherapy REE was increased but undergoes a reduction after treatment, reaching values similar to the controls. For predictive Harris-Benedict equation, stress factors should be added to avoid underestimation of REE before and after chemotherapy. 相似文献
2.
3.
Diane M. Burnard Quentin J. Pittman Brian A. MacVicar 《Journal of neuroendocrinology》1991,3(4):433-439
Intracellular recordings were obtained from pituicytes in the neural lobe of the isolated rat pituitary. Like other glia, pituicytes lacked action potentials in response to depolarizing current injection, but they tended to have more positive resting membrane potentials and higher input resistances than astrocytes in other preparations. Dye-coupling typical of astrocytes was also demonstrated amongst pituicytes, and their morphologies were similar to those of pituicytes stained for glial fibrillary acidic protein. Action potentials, anode-break spikes or barium spikes were not observed in pituicytes, even under conditions that maximized the elicitation of Ca2+-dependent responses. This suggests that pituicytes either have no or a very low density of Ca2+ channels or Ca2+ currents that are too small to generate action potentials. Dynorphin A (1–13), a kappa-opioid agonist, produced long-lasting increases in pituicyte input resistance with no significant changes in resting membrane potential. Dynorphin's action was concentration-dependent and was blocked by the opioid antagonist naloxone. This is consistent with previous reports demonstrating kappa-opioid receptors on pituicytes in the neurohypophysis. The β-adrenergic agonist isoproterenol (100 μM) reversed the increases in pituicyte input resistance produced by opioid application, with no significant changes in resting membrane potential. The fact that pituicytes responded to neurotransmitters suggests a functional link between pituicytes and neurosecretory nerve fibres. 相似文献
4.
5.
Belinda Joy Deal Rebecca A Fountain Carol Ann Russell-Broaddus Melinda Stanley-Hermanns 《Disaster Management & Response》2006,4(4):100-105
Hurricanes Katrina and Rita forced many individuals along the coast of Texas and Louisiana to seek shelter inland. Among the evacuees were residents with special needs and residents of nursing homes and group homes caring for mentally retarded and physically disabled persons. Many nurses volunteered to provide health care for those in need. This article discusses challenges and opportunities that were encountered by nurses volunteering in special-needs shelters. Issues related to human and physical resources, patient care, and confidentiality are discussed including lessons learned. As nurses who cared for evacuees in the shelter, it is hoped some of the lessons learned can be utilized in future disasters. 相似文献
6.
Creating empowering meaning: an interactive process of promoting health with chronically ill older Canadians 总被引:2,自引:1,他引:1
McWilliam C; Stewart M; Brown J; McNair S; Desai K; Patterson M; Del Maestro N; Pittman B 《Health promotion international》1997,12(2):111-123
Many health promotion approaches afford education about disease prevention
and enhancement of one's health status. But strategies for enabling older
people with chronic illness to better mobilize their resources for everyday
living still require development. This practical action research study
explored the experiences of 13 purposefully selected older persons who
participated in a health promotion intervention premised on the adult
education theory of perspective transformation. Findings illuminate health
promotion through a holistic interactive process in which professional and
chronically ill older person together evolved a caring relationship and
enhanced conscious awareness of life and health experiences. Five
health-promoting strategies were identified: building trust and meaning;
connecting; caring; mutual knowing; and mutual creating. Researchers
suggest several important directions to refine professional practice
approaches and health care delivery systems in order to promote the health
of older persons with chronic conditions. 相似文献
7.
Prevention of arginine-vasopressin-induced motor disturbances by a potent vasopressor antagonist 总被引:2,自引:0,他引:2
The antivasopressor analog d(CH2)5Tyr(Me) arginine-vasopressin completely blocked the convulsive-like behavior and other severe motor disturbances which are normally observed following a second central arginine-vasopressin injection. This vasopressor antagonist appears to be selective for arginine-vasopressin-induced motor disturbances, in that the convulsive and motor effects of pentylenetetrazol and somatostatin were not altered significantly by pretreatment with the central antagonist. Results suggest that arginine-vasopressin-induced motor disturbances are mediated via central receptors. The classic antidiuretic (V2) type of arginine-vasopressin receptor does not appear to be involved, since the agonist 1-desamino-8-D-arginine-vasopressin did not elicit convulsive-like behavior or other severe motor disturbances 2 days following a first ('priming') injection of arginine-vasopressin. 相似文献
8.
Elevated serum sodium and potassium levels were recently observed when sampled through a heparin-bonded umbilical catheter and measured with certain ion-selective electrodes. The cationic surfactant, benzalkonium chloride (BZC), is known to falsely elevate those cations in serum. Inasmuch as most heparin-bonded umbilical catheters use BZC during the bonding process, an in vitro study was performed to estimate the quantity of BZC released and the duration of sodium and potassium elevations during pooled sera infusion. Three heparin-bonded umbilical catheters and 3 silastic umbilical catheters were first flushed with 0.3 mL of normal saline and then perfused with pooled sera (sodium, 142 mEq/L; potassium, 4.6 mEq/L) at 2.5 microL/h. Effluent samples were collected from 0 to 8 hours and analyzed by ion-selective electrodes. Elevated serum sodium concentrations from 160 to greater than or equal to 250 mEq/L and potassium concentrations from 6.0 to greater than or equal to 9.6 mEq/L were observed. The BZC concentration in the catheter effluent was measured by mass spectrometry, with peak values of 10 micrograms/mL detected by this method. When varying concentrations of BZC (1 to 100 micrograms/mL) were added directly to pooled serum, a dose-dependent increase in serum sodium was observed. These data demonstrate that BZC released from heparin-bonded umbilical catheters elevates serum electrolyte values measured with some ion-selective electrodes. The observed increase in sodium and potassium concentrations may lead to clinical errors in management. Benzalkonium chloride is associated with myriad of linical symptomatology. Whether this amount of BZC is toxic in the small premature neonate is presently unknown. 相似文献
9.
10.
Andrea J Fradkin Peter A Cameron Belinda J Gabbe 《Journal of Science and Medicine in Sport》2007,10(1):66-71
Golfing injuries have been shown to occur frequently, and injury countermeasures have been suggested to help reduce injury risk. Performing an appropriate warm-up is thought to reduce injury risk, however there is a lack of evidence to support this notion. Therefore this study aimed to investigate the relationships between warm-up participation and injury in a cohort of female golfers. A total of 522 golfers participating in the Victorian Women's Pennant Competition completed the study. Over one-third (35.2%) of the golfers reported having sustained a golfing injury within the previous 12 months, with the lower back the most commonly injured region. Most golfers reported not warming-up prior to play or practice. Golfers who reported not warming-up on a regular basis were more likely to have reported a golfing injury in the previous 12 months than those reporting frequent warm-up participation (OR=45.2; 95% CI: 13.5, 151.7). Less skilled golfers were also less likely to report sustaining a golfing injury than more skilled golfers (OR=0.2; 95% CI: 0.1, 0.5). This study is one of the few to establish an association between warm-up participation and injury. Further prospective studies are warranted to determine whether warm-up reduces injury risk for golf participation. 相似文献