全文获取类型
收费全文 | 854篇 |
免费 | 49篇 |
国内免费 | 6篇 |
专业分类
耳鼻咽喉 | 6篇 |
儿科学 | 14篇 |
妇产科学 | 20篇 |
基础医学 | 83篇 |
口腔科学 | 24篇 |
临床医学 | 100篇 |
内科学 | 160篇 |
皮肤病学 | 4篇 |
神经病学 | 163篇 |
特种医学 | 48篇 |
外科学 | 116篇 |
综合类 | 16篇 |
预防医学 | 69篇 |
眼科学 | 3篇 |
药学 | 57篇 |
肿瘤学 | 26篇 |
出版年
2022年 | 5篇 |
2021年 | 18篇 |
2020年 | 6篇 |
2019年 | 17篇 |
2018年 | 14篇 |
2017年 | 19篇 |
2016年 | 11篇 |
2015年 | 17篇 |
2014年 | 16篇 |
2013年 | 37篇 |
2012年 | 53篇 |
2011年 | 40篇 |
2010年 | 24篇 |
2009年 | 20篇 |
2008年 | 33篇 |
2007年 | 33篇 |
2006年 | 33篇 |
2005年 | 41篇 |
2004年 | 23篇 |
2003年 | 26篇 |
2002年 | 38篇 |
2001年 | 28篇 |
2000年 | 36篇 |
1999年 | 37篇 |
1998年 | 28篇 |
1997年 | 22篇 |
1996年 | 9篇 |
1995年 | 13篇 |
1994年 | 6篇 |
1993年 | 10篇 |
1992年 | 17篇 |
1991年 | 20篇 |
1990年 | 23篇 |
1989年 | 19篇 |
1988年 | 12篇 |
1987年 | 15篇 |
1986年 | 7篇 |
1985年 | 3篇 |
1984年 | 9篇 |
1983年 | 5篇 |
1979年 | 6篇 |
1978年 | 6篇 |
1976年 | 4篇 |
1975年 | 10篇 |
1973年 | 4篇 |
1971年 | 3篇 |
1970年 | 3篇 |
1969年 | 3篇 |
1968年 | 4篇 |
1967年 | 3篇 |
排序方式: 共有909条查询结果,搜索用时 12 毫秒
901.
Gastric emptying of solids in cirrhotic and peritoneal dialysis patients: influence of peritoneal volume load 总被引:1,自引:0,他引:1
Schoonjans R Van Vlem B Vandamme W Van Vlierberghe H Van Heddeghem N Van Biesen W Mast A Sas S Vanholder R Lameire N De Vos M 《European journal of gastroenterology & hepatology》2002,14(4):395-398
INTRODUCTION: A delay in gastric emptying rate has been reported in peritoneal dialysis patients, often normalizing after evacuation of the dialysate. To evaluate the effect of the intraperitoneal volume, we compared this finding with a cirrhotic model in which gastric emptying was studied before and after a large-volume paracentesis. METHODS AND DESIGN: We used the 13C-octanoic acid breath test to measure gastric half-emptying time (T1/2) for solids in patients with alcoholic cirrhosis, non-diabetic peritoneal dialysis patients, and a control population (asymptomatic volunteers). Cirrhotic patients underwent the test on two consecutive mornings before and after an evacuating paracentesis. Peritoneal dialysis patients were studied twice on consecutive days: once with the dialysate present intra-abdominally ("full"), and once with an emptied abdomen ("empty"). Biochemical analysis was carried out on blood samples before the first test. All cirrhotics underwent a 13C-aminopyrine breath test to assess residual liver function. RESULTS: Gastric emptying in cirrhotics showed no difference before or after paracentesis (median T1/2 108.0 min v. 117.9 min), but it was delayed significantly versus normal in both tests. There was no correlation with biochemical parameters, Child-Pugh score, or 13C-aminopyrine breath test results. Gastric half-emptying times of "full" peritoneal dialysis patients (median T1/2 103.1 min) were significantly higher than those of "empty" peritoneal dialysis patients (median T1/2 68.9 min) and asymptomatic volunteers (median T1/2 60.1 min). "Empty" peritoneal dialysis patients showed no gastroparesis. CONCLUSION: In alcoholic cirrhotic patients with ascites, gastric emptying of solids is delayed, independently of the volume of ascites. In peritoneal dialysis patients, gastric emptying was delayed when "full" and normalized after drainage of the dialysate. 相似文献
902.
Under normal conditions, reticulocytes are the youngest erythrocytes released from the bone marrow into circulating blood. They mature for 1-3 days within the bone marrow and circulate for 1-2 days before becoming mature erythrocytes. Measurement of cellular hemoglobin concentration has long been reported by automated hematology analyzers as one of the red blood cell indices. The reticulocyte hemoglobin content (CHr or Ret-He) provides an indirect measure of the functional iron available for new red blood cell production over the previous 3-4 days. Measurement of reticulocyte hemoglobin content in peripheral blood samples is useful for diagnosis of iron deficiency in adults (Mast et al., Blood 2002;99:1489-1491) and children (Brugnara et al., JAMA 1999;281:2225-2230; Ullrich et al., JAMA 2005;294:924-930; Bakr and Sarette, Eur J Pediatr 2006;165:442-445). It provides an early measure of the response to iron therapy increasing within 2-4 days of the initiation of intravenous iron therapy (Brugnara et al., Blood 1994;83:3100-3101). Sequential measurements of reticulocyte hemoglobin content in patients with iron deficiency anemia provide a rapid means for assessing the erythropoietic response to iron replacement therapy (Brugnara et al., Blood 1994;83:3100-3101). It is also an early indicator or iron-restricted erythropoiesis in patients receiving erythropoietin therapy (Fishbane et al., Kidney Int 1997;52:217-222; Fishbane et al., Kidney Int 2001;60:2406-2411; Mittman et al., Am J Kidney Dis 1997;30:912-922; Tsuchiya et al., Clin Nephrol 2003;59:115-123; Chuang et al., Nephrol Dial Transplant 2003;18:370-377). Thus, reticulocyte hemoglobin content is a recent addition to an expanding list of biomarkers that can be used to differentiate iron deficiency from other causes of anemia. 相似文献
903.
Ms Helen Crowe RN BAppSci GDip Epi Biostats MSci Nurs Mr Nicholas Howard Dip Nurs Dr Jane Crowe MBBS Mast GP Psych Mr Max Rutherford BSc Post G Dip MA MAPS Dr Niall Corcoran MB BCh BAO PhD FRACS Anthony Costello MBBS MD FRACS 《International Journal of Urological Nursing》2017,11(3):182-189
Prostate cancer is the most common male cancer, with increasingly longer survival, and many treatment options for advanced disease. Men with prostate cancer report a high level of unmet supportive care needs. To evaluate unmet needs of a small cohort of Australian men with advanced prostate cancer, and their partners, and to assess the impact of attendance at a multidisciplinary allied health clinic on meeting these needs. Fifty patients were referred to the clinic by their treating specialists. Prior to their clinic consultations patients and partners completed study questionnaires to determine their unmet needs, prostate cancer and treatment related quality of life, levels of anxiety and depression, exercise patterns and prostate cancer‐related functional status. Questionnaires were completed again 1 month post‐clinic attendance, and pre‐and post‐clinic scores were compared. Patients reported unmet needs in several domains including psychological and sexuality needs. These showed a small reduction when assessed post‐clinic. Partners also reported needs in the psychological and emotional, and information domains. Thirty‐two percent of patients reported clinical levels of distress when assessed pre‐clinic attendance, reduced to 8% reporting the same level of distress 1 month post‐clinic. The identified high levels of unmet needs and levels of distress of this group of patients and partners highlights the necessity for additional resources to assist these men. A multidisciplinary allied health care prostate clinic as described here may further assist in the comprehensive care of these men and their partners. 相似文献
904.
Intravenous flecainide versus verapamil for acute conversion of paroxysmal atrial fibrillation or flutter to sinus rhythm 总被引:5,自引:0,他引:5
M J Suttorp J H Kingma L Lie-A-Huen E G Mast 《The American journal of cardiology》1989,63(11):693-696
In a single-blind randomized study, the efficacy of intravenous flecainide (2 mg/kg/10 minutes) versus verapamil (10 mg/1 minute) was assessed in 40 patients with paroxysmal atrial fibrillation (AF) or atrial flutter (AFI). The treatment was considered successful if sinus rhythm occurred within 1 hour. Of 20 patients receiving flecainide, 14 of 17 (82%) with AF converted to sinus rhythm, but in 3 patients with AFI flecainide failed. All patients treated with verapamil (17 AF, 3 AFI) showed lower ventricular rates after 1 hour; however, only 1 (6%) with AF converted to sinus rhythm and 1 (6%) converted to AFI. Patients who did not convert to sinus rhythm after treatment with verapamil were treated with flecainide and observed for another hour. After the change to flecainide, 9 of 15 patients (60%) with AF still converted. Thus, 23 of 32 patients (72%) with AF and none of 7 with AFI converted to sinus rhythm after treatment with flecainide. Conversion to sinus rhythm was achieved in 19 of 22 patients (86%) when AF lasted less than 24 hours and in 4 of 10 (40%) when the arrhythmia lasted greater than 24 hours. Transient adverse effects were noted in 10 patients (26%) after flecainide. In summary, flecainide is an effective and safe drug for conversion of paroxysmal AF to sinus rhythm, but ineffective for AFI. Verapamil appears to be of no use for conversion of AF or AFI to sinus rhythm. 相似文献
905.
Mast AE Lee TH Schlumpf KS Wright DJ Johnson B Carrick DM Cable RG Kiss JE Glynn SA Steele WR Murphy EL Sacher R Busch MP;NHLBI Retrovirus Epidemiology Donor Study-II 《British journal of haematology》2012,156(3):388-401
Frequent blood donors become iron deficient. HFE mutations are present in over 30% of donors. A 24-month study of 888 first time/reactivated donors and 1537 frequent donors measured haemoglobin and iron status to assess how HFE mutations impact the development of iron deficiency erythropoiesis. Donors with two HFE mutations had increased baseline haemoglobin and iron stores as did those with one mutation, albeit to a lesser extent. Over multiple donations haemoglobin and iron status of donors with HFE mutations paralleled those lacking mutations. The prevalence of HFE mutations was not increased in higher intensity donors. Thus, in general, HFE mutations do not temper donation-induced changes in haemoglobin and iron status. However, in Black donors there was an increase of H63D carriers at baseline, from 3·7% in first time/reactivated donors to 15·8% in frequent donors, suggesting that the relative effects of HFE mutations on iron absorption may vary between racial/ethnic groups. In secondary analyses, venous haemoglobin decreased more slowly in donors with ferritin ≥12μg/l; and haemoglobin recovery time was shorter in donors with reticulocyte haemoglobin (CHr) ≥32·6pg, indicating that these biochemical measures are better indicators of a donor's response to phlebotomy than their HFE mutation status. 相似文献
906.
Obesity prevention is necessary to address the steady rise in the prevalence of obesity. Although all experts agree that obesity prevention has high priority there is almost no research in this area. There is also no structured framework for obesity prevention. The effectiveness of different intervention strategies is not well documented. Regarding universal prevention little rigorous evaluation has been carried out in larger populations. Obesity prevention has been integrated into community‐wide programmes preventing coronary heart disease. Although effective with respect to reduction in cardiovascular risk factors these programmes did not affect mean body mass index (BMI) of the target populations. Selective prevention directed at high risk individuals (e.g. at children with obese parents) exhibited various degrees of effectiveness. However, at present, definitive statements cannot be made because of the limited number of studies as well as limits in study design. Finally, targeted prevention produced promising results in obese children when compared to no treatment. However, there are only very few long‐term follow‐up data. There is no clear idea about comprehensive interventions studying combinations of different strategies. It is tempting to speculate that predictors of treatment outcome (e.g. psychological and sociodemographic factors) may also serve as barriers to preventive strategies, but this has not yet been investigated. Taken together, obesity prevention should become a high priority research goal. First results of obesity prevention programmes are promising. As well as health promotion and counselling, better school education and social support appear to be promising strategies for future interventions. 相似文献
907.
This study examined the impact of self-reported doctor's depression diagnosis on burden and grief expression in dementia caregivers (N?=?80). Depression was not related to overall grief and burden levels, but influenced the item endorsement pattern on these measures. Depressed caregivers were significantly more likely to endorse items concerning loss of freedom and control in their lives. Furthermore, caregivers with a depression diagnosis scored significantly higher on a personal sacrifice and burden subscale, compared to caregivers who had never received a diagnosis. There was no difference on subscales measuring heartfelt sadness and longing or worry and felt isolation. Caregivers with past depression may not necessarily demonstrate greater grief and burden levels, but may experience these differently than caregivers without past depression. 相似文献
908.
ABSTRACTObjectives: The Symptoms of Dementia Screener (SDS) is an 11-item scale developed to screen for cognitive impairment. We aim to evaluate the psychometric properties of the SDS for use in primary care.Methods: We analyzed data from 192 patients: 25 not impaired, 42 with mild cognitive impairment (MCI), and 125 with dementia. Cronbach’s reliability, convergent validity, and clinical utility were examined. The SDS was investigated at the item level using binary two-parameter model item response theory (IRT) techniques.Results: The SDS demonstrated good reliability (11 items; α = .74). We found negative correlations between SDS and the Mattis DRS-2 (r = ?.523, p < .01). Receiver operating characteristic (ROC) curves demonstrated acceptable clinical utility for detecting MCI and dementia with sensitivities and specificities of 83% and 52% for MCI; 78.4% and 84% for dementia, and 91% and 52% for any impairment. IRT analyses revealed 10 out of 11 items were moderately to very highly related to underlying latent factors of impairment.Conclusions: The SDS demonstrates good psychometric properties and is useful for detecting cognitive impairment in primary care settings.Clinical Implications: The SDS is an effective screening tool that does not require special training for its use in primary care. A positive screen indicates a need for further cognitive testing. 相似文献
909.
Estimates of total body iron indicate 19 mg and 38 mg oral iron are equivalent for the mitigation of iron deficiency in individuals experiencing repeated phlebotomy 下载免费PDF全文
Walter Bialkowski Joseph E. Kiss David J. Wright Ritchard Cable Rebecca Birch Pam D'Andrea Barbara J. Bryant Bryan R. Spencer Alan E. Mast 《American journal of hematology》2017,92(9):851-857
Iron deficiency anemia is a common clinical condition often treated with tablets containing 65 mg of elemental iron. Such doses can elicit gastrointestinal side effects lowering patient compliance. Oral iron supplements also increase hepcidin production causing decreased fractional absorption of subsequent doses. Frequent blood donors often become iron deficient. Therefore, they were enrolled in a two‐year study involving continued blood donations and randomization to receive no pill, placebo, 19, or 38 mg ferrous gluconate for 60 days. Total body iron (TBI) did not change for the subset of donors in the no pill and placebo groups who completed both enrollment and final visits (P = .21 and P = .28, respectively). However, repeated measures regression analysis on the complete dataset estimated a significant decrease in TBI of 52 mg/year for the placebo and no pill groups (P = .001). The effects of 19 and 38 mg iron supplementation on TBI were indistinguishable (P = .54). TBI increased by 229 mg after the initial 60 days of iron supplementation (P < .0001) and was maintained at this higher level with continued iron supplementation following each subsequent donation. The TBI increase was apportioned 51 mg to red cell iron (P < .0001) and 174 mg to storage iron (P < .0001). Changes in storage iron were negatively impacted by 57 mg due to concurrent antacid use (P = .04). These findings in blood donors suggest that much lower doses of iron than are currently used will be effective for clinical treatment of iron deficiency anemia. 相似文献