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71.

Background

Anastomotic leak is a serious complication of low anterior resection (LAR). The risk of leak in stage IV rectal cancer patients treated with synchronous or staged resection of the primary tumour and metastatic sites has not been reported. We measured the incidence of anastomotic leak and its association with clinical outcome.

Methods

With institutional review board approval, patients undergoing LAR and resection of metastatic disease were analyzed from a prospectively collected colorectal database between 1992 and 2010. Data for use of ileostomy, clinical anastomotic leak, and clinical risk score (for liver metastases, n = 86) were collected. Categorical variables were compared with the χ2 test. Estimated overall survival was compared using log-rank method and Cox regression analysis.

Results

A total of 184 patients with LAR and stage IV disease were identified. Of those, 123 had curative resection for disease at distant sites. 72 % underwent simultaneous resection, 28 % staged resection. Median follow-up was 2.9 years for survivors. Anastomotic leak occurred in 6.5 %. There was one perioperative death (not attributable to leak). Overall 3-year survival following a leak was significantly worse compared with patients without a leak (35 vs. 73 %, P = 0.01). Clinical leak was associated with worse survival when controlled for use of diverting stoma, operative year, clinical risk score, and timing of resection of metastatic disease.

Conclusions

In this series of patients with stage IV rectal cancer, anastomotic leak was uncommon. However, patients who developed a clinical leak following surgery had worse survival. This finding was independent of use of diverting stoma or staged resection.  相似文献   
72.
Piperazine designer drugs are a group of synthetic drugs of abuse that have appeared on the illicit market since the second half of the 1990s. The most common derivatives are 1-benzylpiperazine (BZP), 1-(4-methoxyphenyl)piperazine (MeOPP) and 1-(3,4-methylenedioxybenzyl)piperazine (MDBP). They can be consumed as capsules, tablets, but also in powder or liquid forms. Generally, although less potent than amphetamines, piperazines have dopaminergic and serotonergic activities. The aim of this work was to evaluate the toxic effects of BZP, MeOPP and MDBP using Caenorhabditis elegans as in vivo model for acute toxicity, development, reproduction and behavior testing. The LC50 for BZP, MeOPP and MDBP were 52.21, 5.72 and 1.22 mm , respectively. All concentrations induced a significant decrease in the body surface of the worms, indicating developmental alterations, and decrease in the brood size. Worms exposed to piperazine designer drugs also presented a decrease in locomotor activity and mechanical sensitivity, suggesting the possible dysfunction of the nervous system. Neuronal damage was confirmed through the decrease in fluorescence of BY200 strains, indicating loss of dopaminergic transporters. In conclusion, we suggest that piperazine designer drugs lead to neuronal damage, which might be the underlying cause of the altered behavior observed in humans.  相似文献   
73.
The aim of this study was to evaluate the morphological and biomechanical characteristics of a wound entrance on the parietal bone from the impact of projectiles presenting three different calibres. Three-dimensional finite element models of dry human skull and of three projectiles with calibres .380 Auto, .40 S&W and 9 × 19 mm Luger were obtained. These geometries were used to perform a simulation of projectile impact on the parietal bone by the finite element method. We calculated the morphological aspect of the wounds on the external bone surface, the equivalent von Mises stress and the kinetic energy loss. The wounds from the 9 × 19 mm and .380 calibres presented a circular aspect, while the wound from the .40 calibre presented an oval aspect. The 9 × 19 mm caused a major wound area compared with the other calibres. The maximum von Mises stress in the bone was higher from the .40 calibre penetration, and the .380 had the major kinetic energy loss. In conclusion, the 9 × 19 mm and .380 presented similarity in the shape of the entrance hole. The projectile with 9 × 19 mm calibre seems to have greater penetration power and the .40 S&W projectile greater power of destruction and dissipation of energy.  相似文献   
74.

Purpose

One-third of all pregnancies in the United States are conceived within 18 months of a prior live birth. Preventing unintended pregnancies may help to decrease the prevalence of pregnancies with these short interpregnancy intervals. However, data on factors associated with pregnancy intention among women who have had short birth intervals are sparse. Pregnancy Risk Assessment Monitoring System data were used to further evaluate these associations.

Methods

Because only Mississippi and Tennessee Pregnancy Risk Assessment Monitoring System include a survey question about birth interval length, this analysis was limited to women from those states who recently had a short birth interval (n = 384). Pregnancy intention and demographic, lifestyle, and reproductive data were obtained from surveys and birth certificates. Logistic regression was used to obtain odds ratios (ORs) and 95% confidence intervals (CIs).

Results

Nearly 76% of women with short birth intervals reported their pregnancy as unintended. Women who were non-Hispanic black or consumed alcohol during pregnancy had statistically significant increased odds of reporting the pregnancy with a short birth interval as being unintended (OR = 3.98; 95% CI: 1.73–9.16 and OR = 10.56; 95% CI: 1.80–61.83, respectively).

Conclusions

Although all women should be counseled on postpartum contraceptive use, findings suggest that important subpopulations of women may benefit from more targeted counseling during prenatal care visits and the immediate postpartum hospital stay regarding the importance of using contraception to not only better space pregnancies but also prevent unintended pregnancies.  相似文献   
75.
AIM: The aim of this study was to evaluate the influence of four photoactivation systems [quartz tungsten halogen (QTH), light-emitting diode (LED), argon ion laser (AL), and plasma arc curing PAC)] on cementum/dentin and enamel microleakage of Class II restorations using a microhybrid [Z250-3M ESPE] and two packable composites [(SureFil-Dentsply and Tetric Ceram HB-Ivoclair/Vivadent]. METHODS AND MATERIALS: Three hundred sixty "vertical-slot Class II cavities" were prepared at the mesial surface of bovine incisors using a 245 carbide bur in a highspeed handpiece. Specimens were divided into twelve groups (composite-photoactivation systems). Half of the specimens had the gingival margin placed in enamel (n=15) and the other half in cementum/dentin (n=15). Composites were inserted and cured in 2 mm increments according to manufacturers' recommended exposure times. After polishing, the samples were immersed in 2% methylene blue solution, sectioned, and evaluated at the gingival margins. Data were submitted to statistical analysis using the Kruskal-Wallis and Mann-Whitney tests. RESULTS: No significant differences were found among the photoactivation systems and among resin composites (p>0.05). Microleakage was not significantly affected by location (enamel vs. cementum/dentin, p>0.05). These findings suggested neither the photoactivation systems nor the resin composite types might have an effect on the microleakage at gingival margins Class II cavities.  相似文献   
76.
OBJECTIVE: Assess the effect of antioxidant treatment on late memory impairment and early hippocampus oxidative stress after cecal ligation and perforation. SUBJECTS: Male Wistar rats. INTERVENTIONS: Rats underwent sham operation or cecal ligation and perforation. Animals that underwent cecal ligation and perforation were divided into groups: 1) treated with basic support (50 mL/kg saline, 30 mg/kg ceftriaxone, and 25 mg/kg clindamycin every 6 hrs), 2) treated with basic support plus N-acetylcysteine (20 mg/kg N-acetylcysteine at 3, 6, 12, 18, and 24 hrs after cecal ligation and perforation), 3) treated with basic support plus deferoxamine (20 mg/kg deferoxamine at 3 and 24 hrs after cecal ligation and perforation), 4) treated with basic support plus N-acetylcysteine and deferoxamine, or 5) treated with N-acetylcysteine plus deferoxamine. MEASUREMENTS AND MAIN RESULTS: On days 10 and 30 after surgery, the animals underwent behavioral tasks: inhibitory avoidance task, habituation to an open field, and continuous multiple-trials step-down inhibitory avoidance task. The sepsis group showed significantly decreased performance in latency retention compared with the sham group in the inhibitory avoidance task. In the open-field task, the sepsis group presented memory impairment after sepsis. In the continuous multiple-trials step-down inhibitory avoidance task, the sepsis group showed a significant increase in the number of training trials required to reach the acquisition criterion. All these memory impairments were prevented by N-acetylcysteine plus deferoxamine treatment, but not its isolate use. In addition, the combined use of antioxidants attenuated oxidative damage in hippocampus 6 hrs after sepsis induction. CONCLUSIONS: Antioxidant treatment prevented the development of late cognitive deficits in an animal model of sepsis.  相似文献   
77.
Bisphenol A (BPA) is a synthetic non‐steroidal oestrogen used in the production of plastics. BPA can cause alterations in the endocrine system of human beings and animals at varied stages of development. During puberty, altered morphological, sexual behaviour and completion of the epididymal development occur. Therefore, this study aimed to evaluate the effects of BPA on epididymal development during the peripubertal period of rats. Male Wistar rats were treated with BPA via gavage at doses of 20 μg/kg or 200 μg/kg per day [post‐natal day (PND] 36–66). The control group received the vehicles under the same conditions. Feed and water were provided ad libitum. On PND 67, the epididymis was removed, weighed, divided into caput/corpus and cauda sections. It was then used for sperm count determination; histopathological and stereological evaluation; inflammatory cell enzymatic profiling (myeloperoxidase activity – MPO; N‐acetylglucosaminidase – NAG); immunohistochemistry for IL‐6; and evaluation of superoxide anion levels and malondialdehyde (MDA). Exposure to BPA at 200 μg/kg caused a significant increase of MPO activity and immunoreactivity to IL‐6 (interleukin‐6) as well as remodelling of tissue components in the caput/corpus and cauda regions of the epididymis. Under these experimental conditions, it is concluded that BPA alters post‐natal epididymal development.  相似文献   
78.
Canadian Journal of Anesthesia/Journal canadien d'anesthésie - Dexmedetomidine and ketamine may be administered intraoperatively as continuous infusions to provide opioid-sparing...  相似文献   
79.
80.
To verify a possible synergistic effect of smoking and varicocele on the seminal plasma proteome and biological functions, a cross-sectional study was performed in 25 smokers and 24 nonsmokers. Samples were used for conventional semen analysis, functional analysis (DNA fragmentation, acrosome integrity and mitochondrial activity) and proteomics by a shotgun approach. Functional enrichment of biological pathways was performed in differentially expressed proteins. Smokers presented lower ejaculate volume (p = .027), percentage of progressively motile spermatozoa (p = .002), total sperm count (p = .039), morphology (p = .001) and higher percentage of immotile spermatozoa (p = .03), round cell (p = .045) and neutrophil count (p = .009). Smokers also presented lower mitochondrial activity and acrosome integrity and higher DNA fragmentation. We identified and quantified 421 proteins in seminal plasma, of which one was exclusive, 21 were overexpressed and 70 were underexpressed in the seminal plasma of smokers. The proteins neprilysin, beta-defensin 106A and histone H4A were capable of predicting the smoker group. Enriched functions were related to immune function and sperm machinery in testis/epididymis. Based on our findings, we can conclude that cigarette smoking leads to the establishment of inflammatory protein pathways in the testis/epididymis in the presence of varicocele that seems to act in synergy with the toxic components of the cigarette.  相似文献   
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