首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   149篇
  免费   9篇
儿科学   2篇
妇产科学   3篇
基础医学   17篇
口腔科学   3篇
临床医学   15篇
内科学   26篇
神经病学   27篇
特种医学   7篇
外科学   20篇
预防医学   11篇
药学   15篇
肿瘤学   12篇
  2023年   2篇
  2021年   6篇
  2020年   2篇
  2019年   6篇
  2018年   6篇
  2017年   2篇
  2015年   3篇
  2014年   8篇
  2013年   11篇
  2012年   12篇
  2011年   7篇
  2010年   5篇
  2009年   6篇
  2008年   14篇
  2007年   6篇
  2006年   11篇
  2005年   14篇
  2004年   6篇
  2003年   3篇
  2002年   3篇
  2001年   3篇
  2000年   3篇
  1999年   3篇
  1998年   1篇
  1997年   1篇
  1996年   3篇
  1995年   2篇
  1992年   1篇
  1990年   1篇
  1986年   1篇
  1984年   1篇
  1983年   1篇
  1977年   1篇
  1975年   1篇
  1974年   2篇
排序方式: 共有158条查询结果,搜索用时 15 毫秒
1.
The aim of this study was to compare levels of agreement in the assessment of suicide risk by detention center staff procedures compared with those completed by a mental health clinician. Over a 6-month period, 64 young people (mean age 15.0 years; SD+/?1.3) assessed as being acutely suicidal were referred for a clinical mental health assessment and completion of the Adolescent Suicide Questionnaire (ASQ). Cohen's kappa statistic was used to determine inter-judgmental agreement between the detention center, a clinical assessment and ASQ scores. Weak levels of agreement existed in the assessment of suicide. We recommend further work in this area and broad discussion toward development of national guidelines to standardize the assessment of suicide risk for young people in youth detention.  相似文献   
2.
Introduction

Obesity is associated with increased morbidity and mortality in abdominal trauma patients. The characteristics of abdominal trauma patients with poor outcomes related to obesity require evaluation. We hypothesize that obesity is related to increased mortality and length of stay (LOS) among abdominal trauma patients undergoing laparotomies.

Methods

Abdominal trauma patients were identified from the National Trauma Data Bank between 2013 and 2015. Patients who received laparotomies were analyzed using propensity score matching (PSM) to evaluate the mortality rate and LOS between obese and non-obese patients. Patients without laparotomies were analyzed as a control group using PSM cohort analysis.

Results

A total of 33,798 abdominal trauma patients were evaluated, 10,987 of them received laparotomies. Of these patients, the proportion of obesity in deceased patients was significantly higher when compared to the survivors (33.1% vs. 26.2%, p < 0.001). Elevation of one kg/m2 of body mass index independently resulted in 2.5% increased odds of mortality. After a well-balanced PSM, obese patients undergoing laparotomies had significantly higher mortality rates [3.7% vs. 2.4%, standardized difference (SD) = 0.241], longer hospital LOS (11.1 vs. 9.6 days, SD = 0.135), and longer intensive care unit LOS (3.5 vs. 2.3 days, SD = 0.171) than non-obese patients undergoing laparotomies.

Conclusions

Obesity is associated with increased mortality in abdominal trauma patients who received laparotomies versus those who did not. Obesity requires a careful evaluation of alternatives to laparotomy in injured patients.

  相似文献   
3.
4.
5.

Introduction

β-alanine (BAl) and NaHCO3 (SB) ingestion may provide performance benefits by enhancing concentrations of their respective physiochemical buffer counterparts, muscle carnosine and blood bicarbonate, counteracting acidosis during intense exercise. This study examined the effect of BAl and SB co-supplementation as an ergogenic strategy during high-intensity exercise.

Methods

Eight healthy males ingested either BAl (4.8 g day?1 for 4 weeks, increased to 6.4 g day?1 for 2 weeks) or placebo (Pl) (CaCO3) for 6 weeks, in a crossover design (6-week washout between supplements). After each chronic supplementation period participants performed two trials, each consisting of two intense exercise tests performed over consecutive days. Trials were separated by 1 week and consisted of a repeated sprint ability (RSA) test and cycling capacity test at 110 % Wmax (CCT110 %). Placebo (Pl) or SB (300 mg kgbw?1) was ingested prior to exercise in a crossover design to creating four supplement conditions (BAl-Pl, BAl-SB, Pl–Pl, Pl-SB).

Results

Carnosine increased in the gastrocnemius (n = 5) (p = 0.03) and soleus (n = 5) (p = 0.02) following BAl supplementation, and Pl-SB and BAl-SB ingestion elevated blood HCO3 ? concentrations (p < 0.01). Although buffering capacity was elevated following both BAl and SB ingestion, performance improvement was only observed with BAl-Pl and BAl-SB increasing time to exhaustion of the CCT110 % test 14 and 16 %, respectively, compared to Pl–Pl (p < 0.01).

Conclusion

Supplementation of BAl and SB elevated buffering potential by increasing muscle carnosine and blood bicarbonate levels, respectively. BAl ingestion improved performance during the CCT110 %, with no aggregating effect of SB supplementation (p > 0.05). Performance was not different between treatments during the RSA test.  相似文献   
6.

Purpose

Exercise at 50–60 % of peak oxygen consumption (VO2 peak) stimulates maximal fat oxidation rates. Despite a lower estimated work performed; high-intensity intermittent exercise (HIIE) training produces greater fat mass reductions when compared with workload-matched continuous (CON) steady state exercise. No metabolic basis has been documented nor mechanisms offered to explain this anomaly. This study investigated the physiological and metabolic responses of two different workload-matched exercise protocols.

Methods

On separate occasions and at least 1 week apart, eight apparently healthy males cycled for 30 min at either 50 % VO2 peak (CON) or performed repeated 20 s bouts of supramaximal exercise at 150 %VO2 peak separated by 40 s rest (HIIE).

Results

The average heart rate, oxygen consumption, plasma glycerol and free fatty acid concentrations were not different during exercise and recovery between the trials. Plasma lactate and hypoxanthine (Hx) concentrations were elevated and urinary excretion rates of Hx and uric acid were greater following HIIE as compared to CON (P < 0.05).

Conclusion

Exercise-induced plasma Hx accumulation and urinary purine excretion are greater following HIIE and indirectly represents a net loss of adenosine triphosphate (ATP) from the muscle. The subsequent restorative processes required for intramuscular de novo replacement of ATP may contribute to a negative energy balance and in part, account for the potential accelerated fat loss observed with HIIE when compared with CON training programs.  相似文献   
7.
Chronic mild stress (CMS) has been reported to induce an anhedonic-like state in rats that resembles some of the symptoms of endogenous depression in humans. In the present study, CMS-induced behavioural responses along with neurochemical alterations in dopaminergic and serotonergic function in prefrontal cortex, striatum, hypothalamus and hippocampus were examined following treatment with imipramine in Wistar and Sprague-Dawley rats. The CMS procedure lasted 7 weeks in total. Once per week, a 1-h preference test for 1% sucrose solution was conducted. Treatment with imipramine (10mg/kg i.p., once daily) commenced after experimental week 3. CMS induced significant reductions in absolute and relative sucrose intake and sucrose preference in both rat strains but their temporal pattern was different especially during the weeks 0-3. These effects were reversed by IMI. An increase in the dopaminergic and a decrease in the serotonergic activity were observed in the prefrontal cortex in both rat strains following CMS. A decrease in the striatal dopaminergic activity and an increased hippocampal serotonergic activity were also seen in both rat strains following CMS. In Wistar rats, dopaminergic and serotonergic activities were enhanced in the hypothalamus whereas in Sprague-Dawley rats no such stress-induced changes were observed. Notably, the clear decrease in sucrose consumption observed in stressed Wistar rats could be directly associated with a respective increase in the dopaminergic hypothalamic activity. Chronic treatment with imipramine normalized all neurochemical alterations induced by CMS. Our results suggest that a specific and regionally differentiated serotonin-dopamine interaction is directly related to the observed stress-induced anhedonia.  相似文献   
8.
A 26-year old symptom-free woman was admitted to our Clinic for evaluation of hyperprolactinemia. The patient, who had normal menstrual cycles, was found accidentally to have a cystic adnexal mass and was placed on oral contraceptives (OC) for 3 months. During the first OC-cycle a bilateral breast nipple discharge was noticed and an elevated serum prolactin (PRL) was detected (2.7 nmol/l). The OC was discontinued and bromocriptine therapy was started. Serum PRL levels were restored and spontaneous menses resumed. The Pituitary magnetic resonance imaging (MRI), the anterior pituitary function, assessed by dynamic tests, and the thyroid hormone levels were normal. Upon bromocriptine discontinuation, PRL levels increased to 13.8 nmol/l. Poly-ethylene-glycol precipitation of the patient's serum, in two consecutive measurements, demonstrated the presence of macroprolactinemia. Since the patient was asymptomatic, a dopamine agonist was not resumed. Macroprolactinemia is characterized by most authors, as a benign condition with no clinical implications. However, a number of investigators challenge this view, suggesting that in some cases mild symptomatology is present possibly requiring therapeutic intervention.  相似文献   
9.
In general, the biological activation of nephrocarcinogenic chlorinated hydrocarbons proceeds via conjugation with glutathione. It has mostly been assumed that the main site of initial conjugation is the liver, followed by a mandatory transfer of intermediates to the kidney. It was therefore of interest to study the enzyme activities of subgroups of glutathione transferases (GSTs) in renal cancers and the surrounding normal renal tissues of the same individuals (n = 21). For genotyping the individuals with respect to known polymorphic GST isozymes the following substrates with differential specificity were used: 1-chloro-2,4-dinitrobenzene for overall GST activity (except GST theta); 7-chloro-4-nitrobenzo-2-oxa- 1,3-diazole for GST alpha; 1,2-dichloro-4-nitro-benzene for GST mu; ethacrynic acid and 4-vinylpyridine for GST pi; and methyl chloride for GST theta. In general, the normal tissues were able to metabolize the test substrates. A general decrease in individual GST enzyme activities was apparent in the course of cancerization, and in some (exceptional) cases individual activities, expressed in the normal renal tissue, were lost in the tumour tissue. The GST enzyme activities in tumours were independent of tumour stage, or the age and gender of the patients. There was little influence of known polymorphisms of GSTM1, GSTM3 and GSTP1 upon the activities towards the test substrates, whereas the influence of GSTT1 polymorphism on the activity towads methyl chloride was straightforward. In general, the present findings support the concept that the initial GST-dependent bioactivation step of nephrocarcinogenic chlorinated hydrocarbons may take place in the kidney itself. This should be a consideration in toxicokinetic modelling.  相似文献   
10.

Background  

Out of 1705 patients hospitalised for various reasons in the 3rd Internal Medicine Department of the Regional General Hospital of Nikaea, in Piraeus, 146(8,5%) persons were admitted for drug intoxication between November 1999 and November 2000.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号