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91.

Background  

Theories of behavior change indicate that an analysis of barriers to change is helpful when trying to influence professional practice. The aim of this study was to assess the perceived barriers to practice change by eliciting nurses' opinions with regard to barriers to, and facilitators of, implementation of a Fall Prevention clinical practice guideline in five acute care hospitals in Singapore.  相似文献   
92.
93.
BACKGROUND: GnRH agonists constitute a well-documented treatment for premenstrual syndrome (PMS). However, the hypo-estrogenic state induced by the treatment renders it less suitable for long-term clinical use. The aim of the current study was to investigate the efficacy of a low dose GnRH agonist with respect to its ability to relieve premenstrual symptoms and maintain regular ovulatory cycles. METHODS: The effect of a low dose GnRH agonist (buserelin) on luteal phase symptomatology was evaluated in 27 women with severe premenstrual syndrome. The design was doubleblind, placebo-controlled and cross-over. Patients were randomized to either GnRH-agonist intranasally in a dosage of 100 microg once daily for two months or placebo for two months before the cross-over was made. The primary outcome measure consisted of daily symptom ratings for mood and physical symptoms made by the patients throughout the study. Adverse events and hormone concentrations were assessed at visits every second week. RESULTS: Premenstrual irritability and depression were significantly relieved by low dose GnRH agonist. Positive symptoms such as friendliness and cheerfulness were also improved during the premenstrual week. Likewise physical symptoms of swelling and headache displayed a significant improvement during buserelin treatment, whereas breast tenderness scores were unaffected by the treatment. The low dose GnRH agonist treatment regimen induced anovulation in as much as 56% of patients, but these subjects were significantly older than those women who maintained ovulatory cycles throughout the study. CONCLUSION: GnRH treatment significantly reduced premenstrual depression and irritability. However, low dose GnRH therapy is prone to induce anovulation, particularly with increasing age.  相似文献   
94.
The significance of donor age, cause of death, and morbidity for the outcome of renal cadaveric transplantation was evaluated in 534 cases from 1994 through 2001. Half of the kidneys (49.4%) were from donors without identified risk, the others were age 50-64 or > or =65 years, had died of cerebrovascular lesion (CVL), or had known cardiovascular disease, or hypertension. Only death from CVL influenced cumulative graft survival (P=0.04), the actual survival at 6 months being 87% vs 95% with other donors (P=0.004). Clearance of 51Cr EDTA (glomerular filtration rate, GFR) after 1 year was a more sensitive marker of graft quality and was significantly reduced with each tested risk factor. For instance, the median GFR (range) in the three donor age groups was 52 (9-125), 37 (13-83), and 29 (15-60) ml/min, respectively (P<0.0001). Combinations of risk factors significantly increased their impact on GFR. However, the overall results with such suboptimal donors should rather encourage a widening of the donor acceptance criteria.  相似文献   
95.
Nyberg  DA; Mack  LA; Laing  FC; Jeffrey  RB 《Radiology》1988,167(3):619-622
Endovaginal sonography results were compared with quantitatively determined human chorionic gonadotropin (hCG) levels in 84 women referred for early pregnancy complications. Of the 27 with normal intrauterine pregnancies, an intrauterine gestational sac was prospectively identified in one of five cases (20%) in which hCG levels were below 500 IU/L (Second International Standard), four of five (80%) with hCG levels of 500-1,000 IU/L, and all 17 with hCG levels above 1,000 IU/L. In comparison, 17 of the 26 women with ectopic pregnancies (65%) had hCG levels greater than 1,000 IU/L, and none of the 26 had an intrauterine gestational sac. Endovaginal sonography demonstrated an adnexal mass and/or a gestational sac-like structure in 16 of the 17 cases (94%) in which hCG levels were above 1,000 IU/L, compared with only three of the nine (33%) with lower hCG levels (P less than .01). These findings indicate that an intrauterine gestational sac should be normally visualized with endovaginal sonography when the hCG level exceeds 1,000 IU/L, and that visualization of an extrauterine gestational sac and/or adnexal mass is significantly more likely in ectopic pregnancies when the hCG level exceeds 1,000 IU/L.  相似文献   
96.
Summary In a single-blind cross-over study, 6 healthy volunteers took three different formulations, each containing 0.33 g of quinidine base, every 12 h for 96 h. A mean steady state serum level of 1.8 mg/l of quinidine base was produced by bisulphate tablets that dissolved rapidly. Long-acting Quinidine Durules® (sustained-release quinidine bisulphate) produced a mean steady state serum level that was 23% lower (NS) and Longacor® (quinidine arabogalactone sulphate) led to one that was 46% lower (p<0.05). The time taken to reach a steady state was longer after Longacor® than Quinidine Durules®. The results are discussed in relation to the conventional clinical use of quinidine, methods of estimating its concentration in serum, and the relative value of different formulations of quinidine salts.  相似文献   
97.
98.
Thirteen patients with schizophrenia received injections of 25, 50, or 75 mg of long-acting risperidone every 2 wk. Brain D2 receptor occupancy was assessed with [11C]raclopride 2 wk after the last (fifth) injection (day 71) in seven subjects and 2 wk after the third injection (day 44) in one subject. Stable plasma concentrations were reached after the third injection and steady-state concentrations of the active moiety (risperidone + 9-hydroxyrisperidone) after the fourth injection. Steady-state plasma concentrations were maintained for 4-5 wk after the last injection and then declined rapidly. After injections of 25, 50 and 75 mg on day 44 or day 71, D2 receptor occupancy ranged from 25-48%, 59-83% and 62-72% respectively, while plasma active-moiety levels ranged from 4.4-8.8, 15.0-31.1 and 22.5-26.3 ng/ml respectively. The results indicate that brain D2 receptor occupancy at steady state after injections of long-acting risperidone was in the range found in patients effectively treated with 2-6 mg of oral risperidone.  相似文献   
99.
The United Network for Organ Sharing (UNOS) Expanded Criteria Donor (ECD) system utilizes pre-transplant variables to identify deceased donor kidneys with an increased risk of graft loss. The aim of this study was to compare the ECD system with a quantitative approach, the deceased donor score (DDS), in predicting outcome after kidney transplantation. We retrospectively reviewed 49 111 deceased donor renal transplants from the UNOS database between 1984 and 2002. DDS: 0-39 points; >or=20 points defined as marginal. Recipient outcome variables were analyzed by ANOVA or Kaplan-Meier method. There was a 90% agreement between the DDS and ECD systems as predictors of renal function and graft survival. However, DDS identified ECD- kidneys (10.7%) with a significantly poorer outcome than expected (DDS 20-29 points, n = 5,252). Stratification of ECD+ kidneys identified a group with the poorest outcome (DDS >or=30 points). Predictability of early post-transplant events (i.e. need for hemodialysis, decline of serum creatinine and length of hospital stay) was also improved by DDS. DDS predicted outcome of deceased donor renal transplantation better than the ECD system. Knowledge obtained by stratification of deceased donor kidneys can allow for improved utilization of marginal kidneys which is not achieved by the UNOS ECD definition alone.  相似文献   
100.
Summary Three cases of Down's syndrome, one of which had a clinical history of a presenile dementia during final years, were analyzed for the content of tyrosine (Tyr), dopamine (DA), noradrenaline (NA), tryptophan (Try), 5-hydroxytryptamine (5-HT), and 5-hydroxyindoleacetic acid (5-HIAA) in the following regions: the caudate nucleus, the putamen, the thalamus, the mesencephalon, and the hippocampus. A rather generalized reduction of DA, NA, 5-HT, and 5-HIAA was noted in the demented DS case.  相似文献   
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