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   125篇
  免费   3篇
儿科学   2篇
妇产科学   9篇
基础医学   3篇
临床医学   18篇
内科学   31篇
皮肤病学   5篇
神经病学   10篇
外科学   5篇
预防医学   27篇
眼科学   2篇
药学   16篇
  2015年   1篇
  2014年   4篇
  2013年   4篇
  2011年   1篇
  2010年   1篇
  2009年   4篇
  2008年   1篇
  2003年   1篇
  2001年   4篇
  2000年   2篇
  1999年   2篇
  1998年   5篇
  1997年   4篇
  1996年   8篇
  1995年   14篇
  1994年   8篇
  1993年   2篇
  1992年   5篇
  1991年   4篇
  1990年   2篇
  1989年   3篇
  1988年   6篇
  1987年   2篇
  1986年   1篇
  1985年   3篇
  1984年   2篇
  1983年   6篇
  1982年   3篇
  1981年   3篇
  1980年   3篇
  1979年   2篇
  1978年   2篇
  1977年   3篇
  1976年   1篇
  1972年   1篇
  1971年   1篇
  1970年   1篇
  1969年   1篇
  1968年   2篇
  1960年   1篇
  1959年   1篇
  1958年   2篇
  1954年   1篇
排序方式: 共有128条查询结果,搜索用时 15 毫秒
1.
2.
3.
Background: The mechanism of hypergastrinaemia during omeprazole therapy is unclear, but is generally assumed to be entirely a consequence of acid suppression. However, direct stimulation of G cells by omeprazole could also be a factor. In order to further investigate the mechanism of omeprazole-induced hypergastrinaemia, we have studied the effects of the drug on plasma gastrin in patients with achlorhydria, in whom altered acid secretion cannot play a role. Methods: We estimated fasting and peptone meal stimulated plasma gastrin in nine patients (seven female) with pernicious anaemia and achlorhydria, before and on the final day of 4 weeks’dosing with omeprazole 40 mg daily. Results: Despite the high fasting gastrin concentrations, the peptone meal produced a further elevation in plasma gastrin concentrations, median gastrin concentrations rising from 1500 ng/L (range 225–10875 ng/L) to 3750 ng/L (range 585–15600 ng/L) post-prandially (P = 0.004). The median post-prandial rise in plasma gastrin at this initial visit was 44% (3–260%), and the median time interval until plasma gastrin concentrations returned to fasting levels was 120 min (range 10- > 150 min). There was a significant negative correlation between fasting plasma gastrin concentrations and the percentage increase in plasma gastrin levels in response to meal stimulation (Spearman correlation coefficient -0.79, P= 0.01). Fasting plasma gastrin concentrations were similar pre-omeprazole (median 1950 ng/L, range 240–16500 ng/L) and postomeprazole (median 1500 ng/L, range 315–7650 ng/L). Likewise, peak plasma gastrin concentrations were also similar pre-omeprazole (median 2700 ng/L, range 585–16500 ng/L) and post omeprazole (median 3420 ng/L, range 720–11250 ng/L). Conclusions: (i) The hyperplastic G cell mass in patients with pernicious anaemia can be further stimulated by a peptone meal, which causes a prolonged rise in plasma gastrin concentrations. (ii) There is a negative correlation between fasting plasma gastrin concentrations and the percentage increase in plasma gastrin levels in response to meal stimulation. (iii) Omeprazole has no effect on plasma gastrin in achlorhydric patients, which is consistent with its hypergastrinaemic effect being entirely secondary to acid inhibition.  相似文献   
4.
Examination of dietary survey data reveals an inverse relationship between fat and sugar in the diet. The data examined here indicate that high fat diets tend to be low sugar diets and low fat diets tend to be high in sugar.  相似文献   
5.
Objective To determine the day-to-day variation in biochemical measures of iron status in a group of elderly women with rheumatoid arthritis compared with a group of healthy elderly women.Design Venous blood samples were collected from each subject on 3 nonconsecutive days during a 2-week study period; subjects had fasted overnight. Variability in hemoglobin level, hematocrit value, serum iron concentration, total iron-binding capacity, transferrin saturation, serum ferritin concentration, and plasma transferrin receptor level was determined.Subjects Two groups of women, one with rheumatoid arthritis (n=10) and another that was apparently healthy (n=10).Statistical analyses Variance component analysis was used to estimate the biological variation (σ2day) and analytic variation (σ2rep) for each iron index. The coefficient of variation (CV) for each variance component was calculated: coefficient of biological variation = CVday, coefficient of analytic variation = CVrep, and coefficient of a single future determination = CVfd.Results The CVrep for all iron indexes was smaller than the CVday in both groups. The CVday was considerably higher for serum iron concentration and for transferrin saturation than for the other indexes in both groups (16.6% arid 16.6% in healthy subjects and 33.6% and 28.2%, respectively, in subjects with rheumatoid arthritis). The higher CVday for serum iron concentration and transferrin saturation translated into a higher CVfd for these indexes. Because of the higher variance for these two indexes, more sampling days were required for reliable estimates. CVda and CVfd for plasma transferrin receptor level were relatively low.Conclusions These findings corroborate our previous finding that variation of serum ferritin concentration in the elderly is lower than that demonstrated in younger populations. This aging effect persists in the presence of rheumatoid arthritis. Fasting appeared to improve reliability in the determinations for serum iron concentration and transferrin saturation. Variability estimates for the indexes other than serum iron concentration and transferrin saturation were not altered by the inflammation of rheumatoid arthritis. Plasma transferrin receptor level is a reliable index for assessing iron status in populations with rheumatoid arthritis. J Am Diet Assoc. 1996; 96:247-251.  相似文献   
6.
The present study explored the question of whether the grief process affects the characteristics of relationships within the family system or, alternatively, whether family characteristics affect the experience of grief symptoms. Sixty-one people who had recently experienced the death of a parent (82%) or spouse (18%) completed a questionnaire to assess their current grief symptomatology and characteristics of the relationships within their family 4-5 weeks after the death, and again six months later. Results from cross-lagged panel analyses suggested that increased expression of family affect, family cohesion, and both higher total Family Environment Scale and Family Assessment Measure Version III General scores were predictors of fewer grief symptoms over time. Overall, these results suggest that knowledge of a variety of aspects of a family's structure and process shortly after a death may help predict the later grief of the loss of a loved one.  相似文献   
7.
Antibodies are known to be important in mediating malarial immunity, but the influence of the various immunoglobulin isotypes on parasite elimination is unclear. The purpose of this study was to provide basic information on the induction of isotype expression in genetically different mice during primary malaria. Parasitaemias and the serum antimalarial IgM, IgG1, IgG2, IgG3 and IgA antibody titres measured in a radioimmunoassay were followed in outbred and 11 inbred strains of mice infected with 17XNL Plasmodium yoelii. Severity of infection, as judged by length of infection, peak parasitaemias and death, was found to differ between the strains. All strains developed rapid IgM responses, but only 3/11 inbred strains produced significant antimalarial IgG1 levels during primary infection. All strains produced an IgG2 response, which developed slightly more quickly in strains with the least severe courses of malaria. A large variation in the IgG3 response was noted between strains. In general, IgG3 antibodies were the first IgG-isotype to appear in serum. They were detected as early as day 8 in strains that developed mild infections but were not present until around day 20 in strains with the most severe cases of malaria. Only one strain produced detectable antimalarial IgA antibodies. These results show that different patterns of isotype expression are induced in inbred strains of mice during primary P. yoelii infection.  相似文献   
8.
9.
Introduction: Emergency pericardiocentesis during electrophysiology procedures is often associated with significant aspiration of pericardial blood, requiring transfusion. We sought to assess the feasibility of urgent use of an autologous blood recovery system in the electrophysiology laboratory to autotransfuse blood aspirated from the pericardium.
Methods and Results: We retrospectively analyzed Mayo Clinic electrophysiology records for patients who had ablation procedure-related pericardial effusions requiring emergency pericardial drainage during an 8-month period. An autologous blood recovery system was used during pericardiocentesis to separate and clean packed red blood cells from the pericardial aspirate. These cells were returned acutely to the patient intravenously. The procedural safety, aspirated and autotransfused volumes, and efficacy of this approach were evaluated. During the study period, nine patients underwent pericardial drainage with autotransfusion using a cell-salvage instrument during electrophysiology procedures. The mean aspirated volume was 1,078 mL, with a mean autotransfused volume of 390 mL. For four patients, all with aspirated volumes of 1,100 mL or less, autotransfusion alone was sufficient to maintain hemodynamic stability and avoid allogeneic transfusion. One patient required surgical intervention because of ongoing pericardial bleeding. The ablation procedure was completed after aspiration in two patients. No procedural complications related to the use of the cell-salvage system occurred. 
Conclusion: Autologous blood recovery during pericardiocentesis is safe, convenient, and feasible. With early use it may decrease or eliminate the need for allogeneic blood transfusion and, in selected cases, may permit completion of the ablation procedure.  相似文献   
10.
Summary
  • ? Interviews were undertaken with 202 men admitted to five hospitals in northeast England following an uncomplicated first myocardial infarction. The likelihood of patients speaking to a nurse about recovery or seeing a physiotherapist, dietician or specialist rehabilitation nurse, varied considerably between hospitals.
  • ? Whilst virtually all patients received written information concerning some aspect of life-style change or cardiac rehabilitation, the quality and range of information, particularly with regard to information about stress or anxiety, was frequently limited.
  • ? Instructions about seeing a general practitioner following discharge were often vague; formal rehabilitation programmes, where they existed, excluded some patients.
  • ? The study suggests that much patient education is dependent on the provision of written information alone, and that further evaluation of the effectiveness of self-help material supported by nursing input is desirable.
  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