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941.
BACKGROUND: Neurologic impairment after coronary artery bypass grafting is associated with cerebral embolization. An important cause of embolism is aortic manipulation. Constructing both distal and proximal anastomoses during a single period of aortic cross-clamping avoids this source of embolism and may reduce neurologic injury after coronary artery bypass grafting. METHODS: Fifty consecutive patients undergoing coronary artery bypass grafting were prospectively randomized to group 1, in which a single aortic cross-clamping was used to construct distal and proximal anastomoses, or to group 2, in which the proximal anastomoses were each constructed with a partial occluding aortic clamp. Levels of S-100 and troponin-T release were measured preoperatively and postoperatively. RESULTS: Aortic cross-clamp time was significantly longer in group 1, but other preoperative and intraoperative variables were equally represented in both groups. Control group levels of S-100 and troponin-T were similar. Postoperative S-100 levels were significantly higher in group 2 than in group 1 (p < 0.015). No significant difference was found between the groups in postoperative troponin-T levels. CONCLUSIONS: The results of this trial suggest improved cerebral protection is associated with the single aortic cross-clamp technique for coronary artery bypass grafting with no increase in myocardial damage. The single aortic cross-clamp technique is simple and inexpensive. We recommend its wider use.  相似文献   
942.
PURPOSE: Laser tissue soldering has been shown to provide safe and effective tissue closure by creating an immediate leak-free anastomosis with minimal scar formation. We compared the results of laser tissue soldering and conventional suturing for hypospadias repair. MATERIALS AND METHODS: A consecutive group of 138 boys 4 months to 8 years old (mean age 15 months) was divided into a standard suturing (84) and a sutureless laser (54) hypospadias repair group. Urethral repair was defined as simple (Thiersch-Duplay or Snodgrass) and complex (onlay island flap or tube) in 101 and 37 cases, respectively. Laser tissue soldering was performed with 50% human albumin solder doped with 2.5 mg./ml. indocyanine green dye using an 808 nm. diode laser at 0.5 W. In the laser group sutures were used for tissue alignment only. At surgery neourethral and penile length, operative time for neourethral construction and the number of sutures or throws were measured. Postoperatively patients were examined for complications of wound healing, stricture or fistula. RESULTS: Mean patient age, urethral defect severity, type of repair, neourethral length and stenting time plus or minus standard error of mean were not significantly different in the 2 groups. Mean operative time was a fifth as long for laser tissue soldering in simple and complex hypospadias repair compared to controls (1.5 +/- 0.1 and 5.1 +/- 0.3 versus 8.5 +/- 0.8 and 26.7 +/- 1.7 minutes, respectively, p <0.001). The mean number of sutures used for tissue alignment in the laser group for simple and complex repair was significantly less than in controls (3.0 +/- 0.2 and 8.2 +/- 0.6 versus 8.5 +/- 0.8 and 23.2 +/- 1.5, respectively, p <0.001). All patients were followed a mean of 12 months (minimum 6, maximum 22). The complication rate was 4.7% in the laser group and 10.7% in controls with fistula in 2 of 54 cases, and fistula and meatal stenosis in 7 and 2 of 84, respectively. CONCLUSIONS: These preliminary results indicate that laser tissue soldering for hypospadias repair may be performed in almost sutureless fashion and more rapidly than conventional suturing. The ease of the laser technique and the lower complication rate in the laser group indicate that laser tissue soldering is an acceptable means of tissue closure in hypospadias repair.  相似文献   
943.
PURPOSE: Studies of lower urinary tract symptoms in men have been restricted to predominately white populations and these observations may not be generalized to black American men. A goal of the Flint Men's Health Study was to evaluate the prevalence of lower urinary tract symptoms in a community based sample of black American men. MATERIALS AND METHODS: We identified 721 eligible subjects after a 2-stage stratified sampling protocol of black American men residing in Flint, Michigan and an in-home interview. Of these men 364 (50%) completed the study protocol, including serum prostate specific antigen measurement, digital rectal examination, uroflowmetry and transrectal ultrasound. These men comprised our study group. Patients completed the American Urological Association (AUA) symptom and bothersomeness scores. Moderate to severe symptoms and impairment were defined as an AUA symptom score of greater than 7 and bothersomeness score of greater than 3, respectively. Data were stratified by 10-year age groups. RESULTS: Prostate volume increased, while the peak urinary flow rate decreased with increasing age (p <0.001). Total AUA symptom and bothersomeness scores were marginally associated with age (p = 0.08 and 0.01, respectively). Although only 8.2% of the men reported an enlarged prostate and 3% reported being on medical therapy for benign prostatic hyperplasia, moderate to severe lower urinary tract symptoms were reported by 39.6% and moderate to severe impairment was present in 35%. CONCLUSIONS: To our knowledge this is the first study to describe the prevalence of lower urinary tract symptoms and its associations with age, prostate size and peak flow rate in a black American population. A large proportion of the men in this study had from moderate to severe lower urinary tract symptoms, of whom many were undiagnosed and untreated. The AUA symptom score has the potential to identify these men and its validity in black Americans has now been established.  相似文献   
944.
Presently marketed vaginal barrier agents are cytotoxic and damage the vaginal epithelium and natural vaginal flora with frequent use. Novel noncytotoxic agents are needed to protect women from sexually transmitted diseases. One candidate compound is a high-molecular-mass form of soluble poly(sodium 4-styrene sulfonate) (T-PSS). The antimicrobial activity of T-PSS was evaluated in primary culture systems and in a genital herpes murine model. Results obtained indicate that T-PSS is highly effective against herpes simplex viruses, Neisseria gonorrhoeae, and Chlamydia trachomatis in vitro. A 5% T-PSS gel protected 15 of 16 mice from vaginal herpes, compared with 2 of 16 mice treated with a placebo gel. Moreover, T-PSS exhibited little or no cytotoxicity and has an excellent selectivity index. T-PSS is an excellent candidate topical antimicrobial that blocks adherence of herpes simplex virus at low concentrations, inactivates virus at higher concentrations, and exhibits a broad spectrum of antimicrobial activity.  相似文献   
945.
Exercise training leads to tissue anabolism by acting through the growth hormone (GH)-insulin-like growth factor-I (IGF-I) axis, but the role of tissue IGF-I receptors in this process is not known. Erythrocyte IGF-I receptor binding is known to be affected by circulating levels of IGF-I. We hypothesized that training would lead to alterations in erythrocyte IGF-I binding. Thirty-eight adolescent males (mean age 16+/-0.7 yr) were randomized to a control (n=18) or endurance training intervention lasting 5 weeks. Erythrocyte IGF-I binding was measured by standard techniques. Quantity of receptor binding sites (R), binding affinity constant (Kaff), and nonspecific binding (NS) were calculated. Training led to increases (p<0.05) in 1) Kaff x R - an index of overall binding capacity (control, 7.3 +/-8.0%; trained, 60+/-21%); and 2) NS (control, 1.5+/-6.6%; trained 23.2+/-7.5%). Kaff, R, and R/erythrocyte increased in trained subjects, but not significantly so. These results suggest a training-associated upregulation of IGF-I binding. Finally, the unexpected increase in NS may reflect IGF binding protein activity, rather than changes in the erythrocyte IGF-I receptors themselves.  相似文献   
946.
A term infant with congenital varicella syndrome (CVS) is reported. Monoplegia of the left arm and paraplegia were present with no evidence of dermatomal skin scarring. Following death at 12 days of age, autopsy documented severe atrophy and gliosis of the spinal cord. Testing for varicella-zoster virus by the polymerase chain reaction method on brain tissue was positive. This case extends the current understanding of the clinical and pathological features of CVS.  相似文献   
947.
948.
Serial interleukin 6 measurements in the early diagnosis of neonatal sepsis   总被引:4,自引:0,他引:4  
The objective of the present study was to evaluate serial interleukin 6 (IL6) levels in the early diagnosis of neonatal sepsis. Subjects included 255 neonates from the Neonatal Unit of Johannesburg Hospital evaluated for suspected sepsis between February and May 1998. All infants had IL6, full blood count (FBC), C reactive protein (CRP) and blood cultures done at presentation. CRP and IL6 were repeated after 24 h. Infants were categorized into groups according to the likelihood of infection on the basis of clinical presentation, CRP, FBC and culture results, i.e., group 1 (no infection) to group 4 (definite infection). IL6 was compared between the groups by the U-test of Mann-Whitney; stepwise logistic regression was done to establish the best predictors of infection, sensitivity, specificity, positive and negative predictive values were determined. The initial IL6 level was significantly raised in those infants with possible infection [880.67 pg/ml (2966.04), p value 0.0104], probable infection [422.62pg/ml (4077.7), p value 0.0021] and definite infection [11164.39pg/ml (24139.77), p value 0.0000] as compared to those infants without infection [58.65 (182.4)]. The best predictors of infection were the combination of the initial IL6 value and CRP value after 24 h (goodness of fit 97.7 per cent). An initial IL6 value below 20 pg/ml gave a negative predictive value of 90.18 per cent. It is concluded that an IL6 value done at the time of presentation of signs and symptoms suggestive of infection is useful in the early diagnosis of neonatal sepsis. In particular, an initial IL6 value below 20 pg/ml may allow antibiotics to be withheld in a number of infants evaluated for sepsis. There is no benefit in serial determination of IL6 in the diagnosis of neonatal sepsis.  相似文献   
949.
The accurate interpretation of mortality surveys in humanitarian crises is useful for both public health responses and security responses. Recent examples suggest that few medical personnel and researchers can accurately interpret the validity of a mortality survey in these settings. Using an example of a mortality survey from the Democratic Republic of Congo (DRC), we demonstrate important methodological considerations that readers should keep in mind when reading a mortality survey to determine the validity of the study and the applicability of the findings to their settings.  相似文献   
950.
Background: General anaesthesia (GA) for cardiac magnetic resonance imaging (MRI) in patients with congenital heart disease (CHD) is challenging for the anaesthesiologist.  相似文献   
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