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41.
42.
OBJECTIVE: The purpose of this study was to analyze the behavior of the mitral valve ring and the left ventricle in dilated cardiomyopathy. METHODS: We analyzed 68 fixed adult human hearts, divided into 48 hearts with dilated cardiomyopathy of ischemic or idiopathic origin and 20 hearts free of pathologic heart conditions. Digital images of the mitral ring perimeter, attachment of the anterior and posterior leaflets, and fibrous and muscular portions were collected. We also measured the internal perimeter of the left ventricle, the distance from the septum to the anterior and posterior papillary muscles, the distance between the papillary muscles, and the extension of interventricular septum. RESULTS: The analysis of the results showed proportional distribution of the ring's fibrous portion (r2 = 0.98) and muscular portion (r2 = 0.99) according to the degree of mitral valve dilation. Linear regression revealed that the perimeters of anterior and posterior leaflet attachments (r2 = 0.96 and r2 = 0.98, respectively) also had a proportional relation. We did not observe proportionality between the degree of dilation of the mitral ring and the left ventricle. It was observed that dilation of the left ventricle takes place globally in its segments. CONCLUSION: Differently from what was thought, in ischemic or idiopathic dilated cardiomyopathy, dilation of mitral ring is proportional and does not exclusively affect the posterior portion. The degree of left ventricular dilation does not determine the degree of dilation of the mitral ring because they are independent processes. These observations shed new light on the techniques used to correct mitral valve insufficiency in dilated cardiomyopathy.  相似文献   
43.

Background

Prostate biopsy and postbiopsy complications represent important risks of prostate-specific antigen (PSA) screening. Although landmark randomized trials and updated guidelines have challenged routine PSA screening, it is unclear whether these publications have affected rates of biopsy or postbiopsy complications.

Objective

To evaluate whether publication of the 2008 and 2012 US Preventive Services Task Force (USPSTF) recommendations, the 2009 European Randomized Study of Screening for Prostate Cancer and the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial, or the 2013 American Urological Association (AUA) guidelines was associated with changes in rates of biopsy or postbiopsy complications, and to identify predictors of postbiopsy complications.

Design, setting, and participants

This quasiexperimental study used administrative claims of 5 279 315 commercially insured US men aged ≥40 yr from 2005 to 2014, of whom 104 584 underwent biopsy.

Interventions

Publications on PSA screening.

Outcome measurements and statistical analysis

Interrupted time-series analysis was used to evaluate the association of publications with rates of biopsy and 30-d complications. Logistic regression was performed to identify predictors of complications.

Results and limitations

From 2005 to 2014, biopsy rates fell 33% from 64.1 to 42.8 per 100 000 person-months, with immediate reductions following the 2008 USPSTF recommendations (?10.1; 95% confidence interval [CI], ?17.1 to ?3.0; p < 0.001), 2012 USPSTF recommendations (?13.8; 95% CI, ?21.0 to ?6.7; p < 0 .001), and 2013 AUA guidelines (?8.8; 95% CI, ?16.7 to ?0.92; p = 0.03). Concurrently, complication rates decreased 10% from 8.7 to 7.8 per 100 000 person-months, with a reduction following the 2012 USPSTF recommendations (?2.5; 95% CI, ?4.5 to ?0.45; p = 0.02). However, the proportion of men undergoing biopsy who experienced complications increased from 14% to 18%, driven by nonsepsis infectious complications (p < 0.001). Predictors of complications included prior fluoroquinolone use (odds ratio [OR]: 1.27; 95% CI, 1.22–1.32; p < 0.001), anticoagulant use (OR: 1.14; 95% CI, 1.04–1.25; p = 0.004), and age ≥70 yr (OR: 1.25; 95% CI, 1.15–1.36; p < 0.001). Limitations included the retrospective design.

Conclusions

Although there has been an absolute reduction in rates of biopsy and 30-d complications, the relative morbidity of biopsy continues to increase. These observations suggest a need to reduce the morbidity of biopsy.

Patient summary

Absolute rates of biopsy and postbiopsy complications have decreased following landmark publications about prostate-specific antigen screening; however, the relative morbidity of biopsy continues to increase.  相似文献   
44.

Introduction and hypothesis

The aim of this study was to evaluate the correlations between the POP-Q Bp point and the perineal body (Pb) and genital hiatus (Gh) measurements and constipation, anal incontinence, severity of symptoms and quality of life.

Methods

The patients were distributed into two groups according to the posterior vaginal wall Bp point: one group with Bp ≤?1 (without posterior vaginal wall prolapse, control group) and the other group with Bp ≥0 (with posterior vaginal wall prolapse, case group). Demographic data, defecatory dysfunction and SF-36 scores were compared between the groups. Correlations between severity of posterior prolapse (Bp, Gh, Pb and Gh?+?Pb) and severity of bowel symptoms were also calculated.

Results

A total of 613 women were evaluated, of whom 174 were included, 69 (39.7%) in the control group and 105 (60.3%) in the case group. The groups were similar in terms of anal incontinence, fecal urgency and/or constipation. There was no correlation between the severity of constipation and anal incontinence according to the Wexner score, and the severity of posterior vaginal wall prolapse measured in terms of point Bp. There were, however, statistically significant differences in Pb, Gh and Gh?+?Pb between the groups. The Pb and Gh?+?Pb measurements were positively correlated with symptoms of constipation, as well as with the scores of some SF-36 domains, but were not correlated with anal incontinence.

Conclusions

These results suggest that the severity of posterior vaginal wall prolapse is not correlated with constipation or anal incontinence, but Pb and Gh?+?Pb measurements are correlated with constipation and SF-36 scores.
  相似文献   
45.

Objectives

To evaluate the influence of bilateral or left sympathectomy on left ventricular remodeling and function after myocardial infarction in rats.

Methods

Myocardial infarction was induced in rats by ligation of the left anterior descending coronary. Seven days later, rats were divided into 4 groups: the myocardial infarction, myocardial infarction with left sympathectomy, myocardial infarction with bilateral sympathectomy, and sham groups. After 8 weeks, left ventricular function was evaluated with the use of a pressure-volume conductance catheter under steady-state conditions and pharmacological stress. Infarct size and extracellular matrix fibrosis were evaluated, and cardiac matrix metalloproteinases and myocardial inflammatory markers were analyzed.

Results

The myocardial infarction and left sympathectomy group had an increased end diastolic volume, whereas the bilateral sympathectomy group had a mean end-diastolic volume similar to that of the sham group (P < .002). Significant reduction in ejection fraction was observed in the myocardial infarction and left sympathectomy group, whereas it was preserved after bilateral sympathectomy (P < .001). In response to dobutamine, left ventricular contractility increased in sham rats, rising stroke work, cardiac output, systolic volume, end-diastolic volume, ejection fraction, and dP/dt max. Only bilateral sympathectomy rats had significant increases in ejection fraction (P < .001) with dobutamine. Fibrotic tissue and matrix metalloproteinase expression decreased in the bilateral sympathectomy group compared to that in the myocardial infarction group (P < .001) and was associated with left ventricular wall thickness maintenance and better apoptotic markers in noninfarcted myocardium.

Conclusions

Bilateral sympathectomy effectively attenuated left ventricular remodeling and preserved systolic function after myocardial infarction induction in rats.  相似文献   
46.
Even though very precise at describing pelvic organ position, our criticism to the Pelvic Organ Prolapse Quantification (POP-Q) system is its limited ability to quantify the prolapse itself, since it still classifies prolapse into four stages, almost the same way as Baden and Walker (Clin Obstet Gynecol 15(4):1070-1072, 1972) did in 1972. As a result, the same grade can include a wide prolapse intensity range. The objective of this study was to assess inter-observer reliability in the Pelvic Organ Prolapse Quantification Index (POP-Q-I; Lemos et al., Int Urogynecol J 18(6):609-611, 2007) on a prospective randomized trial. Fifty consecutive women were prospectively examined by two members of the urogynecology staff, blinded to each other's results. Spearman's rank correlation was used to assess inter-observer reliability. Excellent correlation coefficients were observed, with an overall coefficient of 96.5% (CI: 0.889-1.042; p < 0.0001). The POP-Q-I is a method that makes POP research more efficient by directly measuring prolapse as a continuous variable, which is statistically more powerful than the categorical variables proposed by the POP-Q system. This study suggests that the POP-Q-I is applicable to clinical POP research.  相似文献   
47.
This paper presents a nonlinear model‐based predictive controller (NMPC) for trajectory tracking of a four‐wheeled omnidirectional mobile robot. Methods of numerical optimization to perform real‐time nonlinear minimization of the cost function are used. The cost function penalizes the robot's position error, the robot's orientation angle error, and the control effort. Experimental results of the trajectories following and the performances of the methods of optimization are presented. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
48.
The purpose of the current study was to compare the workout volume (sets x resistance x repetitions per set) completed during two upper body resistance exercise sessions that incorporated 1 minute versus 3 minute rest intervals between sets and exercises. Twelve trained men completed two experimental sessions that consisted of 5 upper body exercises (i.e. barbell bench press, incline barbell bench press, pec deck flye, barbell lying triceps extension, triceps pushdown) performed for three sets with an 8-RM load. The two experimental sessions differed only in the length of the rest interval between sets and exercises; one session with a 1-minute and the other session with a 3-minute rest interval. The results demonstrated that for each exercise, significantly greater workout volume was completed when resting 3 minutes between sets and exercises (p < 0.05). These results indicate that during a resistance exercise session, if sufficient time is available, resting 3 minutes between sets and exercises allows greater workout volume for the upper body exercises examined.

Key points

  • The length of the rest interval between sets is an important variable when designing a resistance exercise program and may vary depending on the characteristic being emphasized (i.e. maximal strength, hypertrophy, localized muscular endurance, power).
  • Although acknowledged, this variable is rarely monitored precisely in field settings.
  • Previous studies that examined rest interval lengths from 1 to 5 minutes between sets for single exercises demonstrated significant differences in repetition performance and the exercise volume completed.
  • There is a need for further research to compare the workout volume (sets x resistance x repetitions per set) completed over an entire resistance exercise session with different rest intervals between sets.
  • The results of the current study indicate that during a resistance exercise session, if sufficient time is available, resting 3 minutes between sets and exercises allows greater workout volume for the upper body exercises examined.
Key words: Recovery, fatigue, strength, muscle endurance, weight training, strength training  相似文献   
49.
Polychlorinated biphenyls (PCBs) are a group of environmental contaminants widely reported to cause gonadal toxicity in both humans and animals. This study investigated the amelioratory role of quercetin in PCBs‐induced DNA damage in male Wistar rats. Polychlorinated biphenyls were administered intraperitoneally at a dose of 2 mg kg?1 alone or in combination with quercetin (orally) at 50 mg kg?1 for 25 days. Quercetin modulation of PCBs‐induced gonadal toxicity was evaluated using selected oxidative stress indices, comet assay, measurement of DNA concentration and histology of the testes. Administration of PCBs alone caused a significant (P < 0.05) depletion in the total thiol level in testes of treated rats. Conversely, the levels of reactive oxygen species (ROS) and thiobarbituric acid reactive substances (TBARS) production were markedly elevated in testes of PCBs‐treated rats compared with control. Further, PCBs exposure produced statistically significant increases in DNA tail migration, degraded double‐stranded DNA (dsDNA) concentration and histological alterations of testes of the treated rats compared to control. Quercetin cotreatment significantly improved the testicular antioxidant status, decreased DNA fragmentation and restored the testicular histology, thus demonstrating the protective effect of quercetin in PCBs‐treated rats.  相似文献   
50.
Currently, new types of intraocular lenses have been developed aiming to eliminate presbyopia and the use has become more popular. The authors report the case of a patient with bilateral cataract and corneal irregularities and astigmatism higher than 2D in the corneal topography, in which AcrySof ReSTOR intraocular lens was implanted in the left eye associated to relaxing limbal incisions trying to reduce corneal astigmatism. The near and distance postoperative visual acuity were worse than expected, with no improvement with refraction. Apparently, no other reason apart from irregular astigmatism/multifocal lens justified the low vision. After 45 days, with no visual acuity improvement, the intraocular lens was explanted and a monofocal one was implanted. The final corrected visual acuity improved. Thus, the present case emphasizes the need of a correct preoperative selection of patients to implant this type of multifocal lens, with special attention to corneal topography data.  相似文献   
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