The effects of altering time delays of coupled pacing during acute atrial fibrillation

BACKGROUND: Coupled pacing (CP), which consists of delivering a premature electrical stimulation to the heart after the effective refractory period of ventricular activation, is a novel method for controlling ventricular rate during atrial fibrillation (AF). It also has been established that CP improves pump function by enhancing external cardiac work and myocardial efficiency. OBJECTIVE: The purpose of the present study was to determine if two time delays for CP (short and long) would result in similar improvements in ventricular function. METHODS: In a canine model, we applied CP at two time delays (CP-S and CP-L) during two stages: sinus rhythm (SR) and acute AF. The cardiac responses to CP during SR served as the nontachycardic and nondepressed control. During both rhythms, we shortened the coupling interval until we obtained maximal contractility, designated CP-S. Next, we increased the delay until we started to see a measurable secondary contraction (left ventricular pressure development of approximately 20 mmHg). These longer delays were designated CP-L. RESULTS: Our results showed that the ventricular rate of intrinsic activation (VRIA) remained decreased despite prolongation of the time delay of CP during both AF and SR. Also, both delays of CP increased left ventricular systolic pressure (LVSP) and dLVP/dt, which are indices of myocardial contractility. In contrast, CP increased external cardiac work only during AF. Prolonging this time delay did not markedly decrease the improvement in external cardiac work. Myocardial O(2) consumption (MVO(2)) did not significantly change as the result of CP during either SR or AF. Finally, myocardial efficiency improved during AF as the result of CP at both time delays. CONCLUSIONS: In conclusion, shorter time delays for CP increased contractile strength during both SR and AF. However, extending the time delay of CP had minimal effects on diminishing the improved ventricular pump function and energetics that resulted from CP during AF. Thus, the maximal enhancement of myocardial contractility via CP-S was not needed to maintain the improved ventricular function during acute AF when CP is applied.     

成人护理专科教育护理学基础课堂教学设计的探讨

本文以“健康与疾病”为例，介绍了成人护理专科的护理学基础课堂教学设计。主要包括学生的情况分析、授课计划的制定、教学方法的选择、课程内容的优化、教学媒体和教学案例的运用等。同时，提出了调动学生的学习积极性、学生终身学习意识教育及医德教育等问题，从而使学生既能真正获得有用知识，又尽可能地通过考试取得学历文凭。     

Periodontal conditions in insulin-dependent diabetes mellitus.

In the present investigation, the frequency and severity of periodontal disease was assessed in a group of 71 patients with a mean duration of 16.5 years of insulin-dependent diabetes mellitus (IDD). The diabetics, aged 17-63 years, were under treatment at the diabetic outpatient clinic of the III Department of Medicine, University Central Hospital of Helsinki and at two clinics of the Helsinki Health Centre. Based upon their long-term medical records, 44 individuals were assessed to have a poorly controlled insulin-dependent diabetes mellitus (PIDD). At baseline of the present study, the PIDD group had a mean blood glucose level of 11.8 mmol/l and a mean glycosylated hemoglobin (HBA1) level of 10.7%. 27 subjects were classified as having a controlled insulin-dependent diabetes mellitus (CIDD). For each individual, site-specific recordings were made for the plaque index, gingival index, pocket depth, loss of attachment, bleeding after probing, gingival recession and radiographic loss of alveolar bone. Under similar plaque conditions, adult subjects with a long-term PIDD were found to have lost more approximal attachment and bone than subjects with a CIDD (P = 0.046, P = 0.019). These differences were not equally obvious when the subjects were classified according to the history of medical complications, such as retinopathies, neuropathies and nephropathies.     

腓骨支撑术在粉碎性胫腓骨折中的应用研究

目的：研究腓骨支撑术在粉碎性胫腓骨折中的应用价值。方法：回顾性分析1986年以来我院收治的粉碎性胫腓骨折55例临床资料。结果：全部病例均骨性愈合，总优良率95％。结论：腓骨支撑术在治疗粉碎性胫腓骨折中，损伤小，方法简单，易于操作，疗效好。     

Family Stress and Functioning in Children: the Moderating Effects of Children''s Beliefs About Their Control Over Parental Conflict

While factors such as gender and SES have been studied as moderators of stress for children, their perceptions of control have received little attention. In the current study, children's domain-specific perceptions of their control during marital conflict were investigated as potential moderators of the impact of family stress on children's behavior problems, and perceptions of competence. Ninety-four children aged 6-12 years and mothers from families ranging in level of parental conflict from nondiscordant to discordant to physically violent were interviewed. Multiple regression analyses revealed that higher levels of conflict control beliefs acted as compensatory moderators of stress, being associated with lower levels of problem behaviors across stress levels. However, higher conflict control beliefs acted as vulnerability moderators with regard to children's perceptions of competence.     

Association between age and clinical characteristics of renal cell carcinoma in adult patients

AIM: To study the association between age and clinical characteristics of renal cell carcinoma in adult patients. METHODS: Three hundred and ten patients with renal cell carcinoma were classified into three groups: or=60 years group. The clinical characteristics of the three groups were compared to define the association. RESULTS: The male/female ratio was 1.3/1, 2.0/1, 3.3/1 in the three groups, respectively, and a significant difference appeared when comparing the or=60 years group (P=0.010). The respective percentage of incidental renal cell carcinoma was 27.9%, 43.2%, 31.2%, and it was significantly higher in the 41-59 years group than the >or=60 years group (P=0.047). The incidence of poorly differentiated renal cell carcinoma decreased with age increasing (11.6% vs 5.2% vs 2.7%), and there was significant difference between the or=60 years group (P=0.038). In the 相似文献   

双侧内囊前肢毁损术治疗难治性强迫症疗效及随访研究

目的　对难治性强迫症进行双侧内囊前肢毁损术治疗 ,评定手术疗效并进行 2年随访 ,以进一步探索脑外科手术对难治性强迫症的疗效 ,并探讨手术治疗的良好适应症。方法　对 2 8例难治性强迫症患者进行双侧内囊前肢毁损术治疗 ,并分别在手术前、手术后二周、手术后三月、手术后六月、手术后一年、手术后二年进行Y BOCS、HAMA、HAMD量表评定及术后疗效评定。结果　 (1)强迫症患者手术后各期Y BOCS评分、HAMA评分与手术前比较均下降 ,有极显著差异 (P <0 .0 0 1) ;(2 )手术后各期Y BOCS的强迫思维评分均有明显下降 (P <0 .0 0 1) ,强迫行为在手术后 1年和 2年 ,与手术前比较无明显改变 (P >0 .0 5 ) ;(3)手术后 2年的总有效率为 5 3.5 % ,明显低于手术后 3月的总有效率 (P <0 .0 1)。结论　采用双侧内囊毁损术有相当的治疗效果 ,对于难治性强迫症患者可作为一种补充治疗手段 ;手术治疗对强迫行为的长期疗效较差 ,以严重的强迫思维为主的难治性强迫症患者为手术更好的适应症。     

Diet and premenopausal bilateral breast cancer: A case-control study

We investigated associations between diet and premenopausal bilateral breast cancer in a familial matched case-control study. We studied 140 cases from population-based registries in Los Angeles County (California) and Connecticut, and from the major hospitals in the southern parts of the Province of Quebec. Unaffected sisters of the cases served as matched controls (222 total). Dietary intake were assessed with a food frequency questionnaire. Total fat, monounsaturated fat, polyunsaturated fat, oleic acid, and linoleic acid intake was inversely associated with premenopausal bilateral breast cancer risk. Consumption of carbohydrates (and sweetened beverages) was associated with an increased risk. We observed no associations for dietary fiber, antioxidants, or major food groupings, but we did observe inverse associations for intake of low fat dairy products and tofu. These findings suggest that monounsaturated and polyunsaturated fats, as well as soy foods, might reduce the risk of premenopausal bilateral breast cancer.     

原发性闭角型青光眼发病危险因素的病例对照研究

为探讨原发性闭角型青光眼的发病危险因素，对１０３例原发性闭角型青光眼患者和９５例非青光眼对照者进行了回顾性病例对照研究。结果发现原发性闭角型青光眼的主要危险因素有青光眼家族史、脾气暴躁及易激动、近距离用眼职业和高血压病，未发现吸烟、饮酒、糖尿病、近视眼和ＡＢＯ血型与原发性闭角型青光眼的发病有统计学联系。     

同济医科大学控烟活动及效果评价

我校自1993年开展控烟工作，1995年9月开始创办无吸烟大学校园，采取了卫生宣教和行政干预等综合措施，并进行了效果评价。高强度干预措施实施前期（1995年3月）和中期（1996年10月）相比，男医学生和男女学生平均吸烟率分别从16.3％和11．4％下降到9．6％和5．94％；男教工和男女教工平均吸烟率分别从28．6％和13．8％下降到13．9％和8．86％。