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排序方式: 共有803条查询结果,搜索用时 15 毫秒
1.
2.
A modified protein-bound cobalamin absorption test was used to study dietary cobalamin absorption in healthy adults of different age groups and patients with isolated low serum concentrations of cobalamin. Dietary cobalamin absorption was significantly reduced in healthy adults aged 55-75 years compared with young adults, with a further reduction in those older than 75 years. No difference was detected between dietary cobalamin absorption in patients with isolated low serum cobalamin and controls of a similar age group. Cobalamin malabsorption was associated with elevated serum gastrin. The diagnostic value of this protein-bound cobalamin absorption test in the elderly was limited by the frequent finding of reduced absorption in healthy elderly people with normal serum cobalamin concentrations. The performance of such tests should be evaluated in different age groups before application in diagnosis. 相似文献
3.
K T Kray E N Squire W R Tipton J C Selner J O'Dea H S Nelson 《The Journal of allergy and clinical immunology》1985,76(4):623-627
A formulation of 2% cromolyn sodium (CS) ophthalmic solution without the preservative, 2-phenylethanol, was compared with placebo in 58 patients with seasonal allergic conjunctivitis. Selection was based on history and positive skin tests. Neither immunotherapy nor use of antihistamines was allowed. This study was double-blinded and stratified by RAST scores to assure comparable groups. Either CS or placebo was used six times daily. Patients were observed weekly for 5 weeks during the peak of the fall weed-pollen exposure. Nasal symptoms were treated as required with beclomethasone nasal spray, and uncontrolled ocular symptoms were treated with boric acid and ephedrine solution. Nasal and ocular symptoms were recorded. There was a significant suppression of eye symptoms in the group receiving CS ophthalmic solution (p less than 0.02) during weeks 2, 4, and 5. There was a trend for nasal symptoms and the requirement for nasal beclomethasone to be less in patients receiving CS. 相似文献
4.
The effectiveness of an antiarrhythmic drug is judged by the degree of ventricular arrhythmia suppressed by the drug. It has been suggested that a certain degree of ventricular arrhythmia suppression should be targeted to prove efficacy. Targets used to define the effectiveness of an antiarrhythmic agent included an 80% reduction in the ventricular premature complexes (VPCs) and 90% suppression of nonsustained ventricular tachycardia (NVT) episodes or complete abolition of runs of sustained VT (SVT) [1]. Other dose-adjusted antiarrhythmic trials have attempted to achieve either isolated control of the PVCs of greater-than-or-equal70% [2--5] with the suppression of the high grades of arrhythmia such as couplets and NVT of >90% and 100%, respectively [2, 3]. Such targets of arrhythmia suppression were recommended to avoid errors encountered with the occurrence of the spontaneous variability of ventricular arrhythmia and to be confident that antiarrhythmic therapy has produced a true drug effect [6]. Presently, there is no evidence that suppression of these arrhythmias with type I antiarrhythmic drugs is likely to reduce sudden death [4, 6]. The survival of patients with frequent VPCs and high-grade forms (couplets [C], NVT) and organic heart disease is not dependent on the degree of arrhythmia suppression. The survival of patients with low LVEF of <40% and runs of NVT is improved and is similar to that of patients with good LVEF of greater-than-or-equal40%. Such a lack of correlation between arrhythmia suppression and survival might be a unique feature of the antifibrillatory drugs and might not be applied to the antiectopic drugs. If a high degree of arrhythmia suppression is not needed, lower targets of suppression may be necessary. Lower drug dosages may improve the risk--benefit ratio of antiarrhythmic treatment. 相似文献
5.
R. C. Habito M. Barnett A. Yamamoto D. Cameron-Smith K. O'Dea P. Zimmet G. R. Collier 《Acta diabetologica》1995,32(3):187-192
The aim of this study was to examine wholebody glucose turnover and glucose uptake into individual tissues inPsammomys obesus. The animals were classi-fied according to the level of circulating glucose and insulin in the fed state: group A was normoglycaemic and normoinsulinaemic (glucose <8.0 mmol/l, insulin <150 mU/l), group B was normoglycaemic and hyperinsulinaemic (glucose <8.0 mmol/l, insulin 150 mU/l), and group C was hyperglycaemic and hyperinsulinaemic (glucose 8.0 mmol/l, insulin 150 mU/l). The animals were deprived of food for 6 h, after which they were anaesthetized and cannulated, using the jugular vein for infusions and the carotid artery for blood sampling. Whole-body glucose turnover was measured using a primed-continuous infusion of 6-[3H]-glucose and saline to quantitatively assess hepatic glucose production (HGP), glucose disposal (Rd), and the metabolic clearance rate of glucose (MCR). Following the 2-h infusion period, the glucose metabolic index (Rg) of individual tissues was measured using a fixed-dose bolus of 2-deoxy-[14C]glucose. Under the steady-state conditions of the experiment, HGP was assumed to be equal to Rd, and both variables were found to be significantly correlated to the fasting glucose concentration (r=0.534,P<0.05,n=19). On the other hand, MCR was found to be inversely correlated to the fasting plasma glucose concentration (r=0.670,P<0.01,n=19). When the animals were divided into three groups as described above, HGP in group C animals was significantly elevated compared with group A (20.8±2.6 vs 12.7±0.6 mg · kg–1 · min–1;P<0.05), and MCR showed a tendency to be lower in group C than group A, although the difference was not statistically significant. HGP and MCR were not significantly different between groups A and B. Measurement of the glucose metabolic index in individual tissues showed that group C animals had significantly higher Rg values in muscles and adipse tissues compared with those in group A (P<0.05). In addition, Rg in group B white gastrocnemius and soleus were significantly higher than in group A despite similar rates of HGP and levels of glycaemia. These findings suggest that an early increase in skeletal muscle glucose uptake and hyperinsulinaemia can be demonstrated in group BPsammomysobesus before significant hyperglycaemia. 相似文献
6.
Drew PJ Cule N Gough M Heer K Monson JR Lee PW Kerin MJ Duthie GS 《Journal of the Royal College of Surgeons of Edinburgh》1999,44(1):55-56
"Calmanisation" of surgical training and the introduction of the "New Deal" on doctor's hours has led to a reduction in "in service" training and a proliferation of training courses. Little research has been done into the optimum design of these courses. Education theory has shown that individuals have optimal learning styles and that these styles tend to be generalised across professional groups. It was decided, therefore, to investigate the optimal learning styles of basic surgical trainees. A learning style inventory was used to assess the preferred learning style of 52 basic surgical trainees. The predominant learning styles (86.5%) were convergent (n = 31) or accommodative (n = 14) whilst only 5 (9.6%) assimilative and 2 (3.9%) divergent styles were detected. Convergent and accommodative learners rely principally on hands on experience and problem solving as their optimal learning technique. Given the shorter hours and duration of Basic Surgical Training, in service practical training and surgical courses should be structured accordingly. 相似文献
7.
The effectiveness of an antiarrhythmic drug is judged by the degree of ventricular arrhythmia (VA) suppression. We evaluated the relationship between the degree of VA suppression and survival in a dose-adjusted trial of 110 symptomatic patients treated with amiodarone. Cohorts had left-ventricular ejection fraction (LVEF) of 41 plus minus 18%, ventricular premature contractions (VPCs) of 445 plus minus 571 h, couplets (C) of 733 plus minus 1498 24 h and nonsustained (N) ventricular tachycardia (VT) of 65 plus minus 217 24 h; these conditions were followed for 15 plus minus 11.5 months. Amiodarone was initiated with an oral loading of 670 plus minus 111.7 mg per day for 10 days and continued on maintenance of 274.9 plus minus 102 mg per day. Survival rates of responders and nonresponders with VPCs <70%, 70--89%, greater-than-or-equal90%; C greater-than-or-equal 90%; NVT (100%); and the response to all 3 criteria (suppresion of VPCs greater-than-or-equal70%, C greater-than-or-equal 90% and complete abolition of NVT) were not statistically significant. Survival rates as a function of LVEF <40% (51 patients) or greater-than-or-equal40% (59 patients), as well as responders or nonresponders to all three criteria, were not significant (p = NS). We conclude that, in patients treated with low-dose amiodarone, the degree of VA suppression of PVCs, C and NVT does not predict survival; the survival of patients with LVEF <40% improved irrespective of VA suppression; and criteria for VA suppression should be reassessed at lower levels of suppression for the improvement of the drug risk:benefit ratio. More improvement is not necessarily better. 相似文献
8.
Gilmore's groin repair in athletes 总被引:2,自引:0,他引:2
Brannigan AE Kerin MJ McEntee GP 《The Journal of orthopaedic and sports physical therapy》2000,30(6):329-332
Incapacitating groin pain is a frequent problem among athletes and its etiology may be multifactorial. A specific clinical syndrome relating to injury to the lower abdominal wall has been described and successfully treated by O. J. Gilmore. This paper presents our results of 100 consecutive groin repairs in 85 young athletes using a diagnostic and therapeutic strategy similar to Gilmore's. Ninety-six percent of our patients returned to competitive sport within 15 weeks; we suggest that this is an appropriate therapeutic intervention for athletes who develop chronic incapacitating groin pain. 相似文献
9.
10.
BACKGROUND: Endocrine therapy for breast cancer is now well established and with the identification of a second oestrogen receptor, ERbeta, 3 years ago it is timely to review the possible significance of this receptor in breast cancer management. METHODS: An up-to-date review of the current literature concerning the role and possible implications of ERbeta in human breast cancer was undertaken. RESULTS: Wild-type and variant ERbeta are expressed in human breast tumours. Expression of ERbeta correlates with accepted prognostic indicators including lymph node status and tumour grade. Furthermore, levels of ERbeta messenger RNA alter during carcinogenesis and are upregulated in breast tumours that develop antioestrogen resistance. CONCLUSION: ERbeta has potential as a novel clinical prognostic marker in breast cancer, particularly in determining tumours that are resistant to tamoxifen. 相似文献