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851.
Background
Emergent appendectomy (EA) in children is still considered surgical dogma and continues to be recommended as a standard of care. This study examined whether emergent operation has any outcome advantages over urgent operation.Methods
The charts of children treated for appendicitis during a recent 28-month period at 2 children's hospitals, where appendectomies are not performed between midnight and 7 am, were reviewed. Outcomes were compared between patients who underwent EA (within 8 hours of presentation) vs those who underwent urgent appendectomy (UA, after 8 hours).Results
Three hundred sixty-five children met the criteria for the study. One hundred sixty-one (44%) were in the EA group (5.3 ± 2.1 hours), and 204 (56%) were in the UA group (16.8 ± 9.7 hours). The incidence of gangrenous or perforated appendicitis was significantly higher in the EA group (47% vs 36%, P = .04). There were no significant differences between EA and UA in postoperative outcomes, including readmissions (3.7% vs 1.0%, P = .08), wound infections (0.6% vs 2.4%, P = .17), or postoperative abscesses (1.9% vs 1.5%, P = .77). There were no significant differences in average hospital stay or average hospital charges between EA and UA (3.2 days for both, $14,775 vs $14,850), respectively.Conclusions
Emergent appendectomy in children has no advantages over UA with respect to gangrene and perforation rates, readmissions, postoperative complications, hospital stay, or hospital charges. Performance of a UA at a time convenient to the surgeon should be considered within the standard of care. 相似文献852.
Oh JD Karam SM Gordon JI 《Proceedings of the National Academy of Sciences of the United States of America》2005,102(14):5186-5191
Helicobacter pylori is generally viewed as an extracellular pathogen. We have analyzed the tropism of H. pylori clinical isolates in a gnotobiotic transgenic mouse model of human chronic atrophic gastritis, a preneoplastic condition. These mice lack acid-producing parietal cells and have an amplified population of dividing gastric epithelial progenitors (GEPs) that express NeuAc alpha 2,3Gal beta 1,4-glycans recognized by H. pylori adhesins. Scanning confocal and transmission electron microscopic studies of stomachs that had been colonized for 1 month or 1 year revealed intracellular bacterial collections (IBCs) in a small subset of multi- and oligopotential epithelial progenitors. Transmission electron microscopic and multilabel immunohistochemical analyses disclosed bacteria with several morphotypes, including spiral-shaped, in the cytoplasm and endosomes. Several stages in IBC evolution were documented, from a few solitary bacteria to consolidated populations in dividing and nondividing GEPs, to microorganisms traversing breaches in the GEP plasma cell membrane. IBC formation was not a unique feature of H. pylori strains isolated from patients with chronic atrophic gastritis. The notion that adult mammalian epithelial progenitors can function as a repository for H. pylori broadens the view of host habitats available to this and perhaps other pathogens. 相似文献
853.
854.
855.
Rhizomelic chondrodysplasia punctata (RCP), a rare autosomal recessive disease characterized by a disorder of peroxisome metabolism,
has been shown to affect multiple organ systems. A neonate presenting with a colonic perforation in the first few hours of
life was subsequently diagnosed with RCP. A literature search revealed no previous reports of intestinal perforation associated
with RCP. Intestinal perforation should be added to the list of medical complications associated with RCP. 相似文献
856.
El-Haggar S El-Ashmawy S Attia A Mostafa T Roaiah MM Fayez A Ghazi S Zohdy W Roshdy N 《Asian journal of andrology》2006,8(6):709-712
Aim:To access beta-endorphin levels in serum as well as seminal plasma in different infertile male groups.Methods:Beta-endorphin was estimated in the serum and seminal plasma by enzyme-linked immunosorbent assay(ELISA)method in 80 infertile men equally divided into four groups:non-obstructive azoospermia(NOA),obstructive azoosper-mia(OA),congenital bilateral absent vas deferens(CBVAD)and asthenozoospermia.The results were compared tothose of 20 normozoospermic proven fertile men.Results:There was a decrease in the mean levels of beta-endorphin in the seminal plasma of all successive infertile groups(mean±SD:NOA 51.30±27.37,OA 51.88±9.47,CBAVD 20.36±13.39,asthenozoospermia 49.26±12.49 pg/mL,respectively)compared to the normozoospermicfertile control(87.23±29.55 pg/mL).This relation was not present in mean serum level of beta-endorphin betweenfour infertile groups(51.09±14.71,49.76±12.4,33.96±7.2,69.1±16.57 pg/mL,respectively)and the fertilecontrol group(49.26±31.32 pg/mL).The CBVAD group showed the lowest seminal plasma mean level of beta-endorphin.Testicular contribution of seminal beta-endorphin was estimated to be approximately 40%.Seminal beta-endorphin showed significant correlation with the sperm concentration(r=0.699,P=0.0188)and nonsignificantcorrelation with its serum level(r=0.375,P=0.185)or with the sperm motility percentage(r=0.470,P=0.899).Conclusion:The estimation of beta-endorphin alone is not conclusive to evaluate male reproduction as there aremany other opiates acting at the hypothalamic pituitary gonadal axis.(Asian J Androl 2006 Nov;8:709-712) 相似文献
857.
Stoszek SK Abdel-Hamid M Saleh DA El Kafrawy S Narooz S Hawash Y Shebl FM El Daly M Said A Kassem E Mikhail N Engle RE Sayed M Sharaf S Fix AD Emerson SU Purcell RH Strickland GT 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2006,100(2):95-101
The epidemiology of hepatitis E virus (HEV), an enterically-transmitted cause of acute viral hepatitis (AVH), is not fully understood. During outbreaks on the Indian subcontinent and elsewhere, HEV causes severe AVH with mortality rates around 20% during pregnancy. In Egypt, where prevalence of HEV antibodies (anti-HEV) in rural communities is very high, severe HEV-caused AVH in pregnant women has not been reported. This study examined a cohort of 2,428 pregnant women in the Nile Delta to assess prevalence of, and risk factors for, anti-HEV and correlated these with history of liver disease. Anti-HEV prevalence was 84.3%. Several risk factors associated with anti-HEV included older age, many siblings, not using soap to wash produce and frequent contact with cats. History of jaundice and liver disease was rare and not increased in those having anti-HEV. Our results confirm Egypt's high HEV endemicity and show that almost all women of childbearing age in these communities had prior HEV exposures without a history of liver disease. Reasons for the lack of clinical hepatitis remain unclear but could be the result of early childhood HEV exposures, producing long-lasting immunity and/or modify subsequent responses to exposure. Alternatively, the predominant HEV strain(s) in Egypt are less virulent than those in South Asia. 相似文献
858.
859.
We report a term male neonate who was born with a large, red, tubular, mucosa-lined umbilical mass containing a patent lumen. Prenatal ultrasonographic screening at 20 to 28 weeks of gestation revealed a large cyst at the umbilicus, communicating with the urinary bladder. The cyst resolved at 32 weeks, and a small solid mass was newly seen on the fetal abdominal wall, inferior to the umbilical cord insertion. At operation, the mass was discovered to be the prolapsed, open, everted dome of the urinary bladder. The dome was resected, and the bladder was repaired in 2 layers after identification of the ureteral orifices.Bladder prolapse through a patent urachus can be predicted by prenatal ultrasound and has a distinct neonatal appearance. 相似文献
860.
Purpose The aim of this study was to investigate the mechanism of the effect of wet granulation process on the compaction properties
of microcrystalline cellulose (MCC).
Methods MCC alone and with hydroxypropyl cellulose (HPC) as a binder were wet granulated by a high-shear process using different granulation
parameters (over- and undergranulated). Overgranulated batches were also ball milled after drying and compared to the unmilled
material. MCC starting material and granulation were characterized for particle size distribution, surface area, porosity,
and isothermal moisture uptake. Compaction behavior of the MCC and granulations was also studied using a compaction simulator.
Results In all cases, the wet granulation process decreased MCC primary particle porosity. Wet granulation also reduced compactibility
of MCC to different degrees. Overgranulated batch with HPC showed the lowest compactibility and was less compactible than
the batch without HPC granulated using the same parameters. Ball-milled material showed an increase in porosity and was significantly
more compactible than the unmilled granulation from the same batch.
Conclusions The decrease in MCC compactibility after granulation is associated with the decrease in MCC primary particle porosity and
in some cases with the formation of large dense granules as well. Under certain conditions, milling seems to counteract the
effect of wet granulation on MCC compactibility. 相似文献