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961.

Background  

Obstructed abdominal wall hernias have been reported to be the leading cause of mechanical intestinal obstruction (MIO) among adults in developing countries. In the developed countries, postoperative adhesions are the commonest cause. With the worldwide improvements in health services and education, especially in developing countries, we aimed to determine the effects of these improvements on the patterns and outcomes of management of MIO in Jordan  相似文献   
962.
Traumatic brain injury (TBI) induces a cascade of primary and secondary events resulting in impairment of neuronal networks that eventually determines clinical outcome. The dynorphins, endogenous opioid peptides, have been implicated in secondary injury and neurodegeneration in rodent and human brain. To gain insight into the role of dynorphins in the brain's response to trauma, we analyzed short-term (1-day) and long-term (7-day) changes in dynorphin A (Dyn A) levels in the frontal cortex, hippocampus, and striatum, induced by unilateral left-side or right-side cortical TBI in mice. The effects of TBI were significantly different from those of sham surgery (Sham), while the sham surgery also produced noticeable effects. Both sham and TBI induced short-term changes and long-term changes in all three regions. Two types of responses were generally observed. In the hippocampus, Dyn A levels were predominantly altered ipsilateral to the injury. In the striatum and frontal cortex, injury to the right (R) hemisphere affected Dyn A levels to a greater extent than that seen in the left (L) hemisphere. The R-TBI but not L-TBI produced Dyn A changes in the striatum and frontal cortex at 7 days after injury. Effects of the R-side injury were similar in the two hemispheres. In naive animals, Dyn A was symmetrically distributed between the two hemispheres. Thus, trauma may reveal a lateralization in the mechanism mediating the response of Dyn A-expressing neuronal networks in the brain. These networks may differentially mediate effects of left and right brain injury on lateralized brain functions.  相似文献   
963.
Abstract Background and Purpose: Flexible working angles and fine optical visualization are major requisite factors in performing laparoendoscopic single-site (LESS) urologic procedures. Multiple mechanical design approaches have been used to develop deflectable laparoscopes for LESS procedures. We compared the optical characteristics of three such devices using a bench top approach to simulate LESS in straight and deflected positions. Materials and Methods: A 10-mm fixed-rod rotating lens device (Storz EndoCameleon) and two 5-mm articulating devices (Olympus EndoEye and Stryker IdealEye) were compared using standard industry testing protocols for image resolution (United States Air Force-1951 test target), distortion (multifrequency grid distortion target), and color reproducibility (Gretag Macbeth color checker). Results: The 10-mm fixed-rod rotating lens system demonstrated the highest image resolution (5.04 line pairs/mm), but also the highest distortion (22.8%). Among the 5-mm flexible articulating laparoscopes, resolution was superior with the Olympus EndoEye (4.00 line pairs/mm) compared with the Stryker IdealEye (3.17 line pairs/mm). Distortion (7.0%) and color reproduction (1.18) were superior with the IdealEye vs the EndoEye (18.8 %, 1.27). Laparoscope deflection resulted in attenuation of resolution by 11% with both articulating models, but not with the fixed rod system. Conclusions: Definition of these optical characteristics may inform further development and selection of laparoscopic systems optimized for LESS surgery. A narrow but flexible camera can be crucial in the limited working space available during these procedures. Further investigation is warranted to determine if these objective findings translate into improved surgeon performance.  相似文献   
964.
965.
Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative condition, respiratory failure being the commonest cause of death. Quality of life and survival can be improved by supporting respiratory function with non-invasive ventilation. Transcutaneous carbon dioxide monitoring is a non-invasive method of measuring arterial carbon dioxide levels enabling simple and efficient screening for respiratory failure. The aim of this study was to validate the accuracy of carbon dioxide level recorded transcutaneously with a TOSCA 500 monitor. It is a prospective, observational study of 40 consecutive patients with ALS, recruited from a specialist ALS clinic. The partial pressure of carbon dioxide (PCO(2)) in each patient was determined by both transcutaneous monitoring and by an arterialized ear lobe capillary blood sample. The carbon dioxide (CO(2)) levels obtained with these two methods were compared by Bland-Altman analysis. The results showed that the mean difference between arterialized and transcutaneous readings was - 0.083 kPa (SD 0.318). The Bland-Altman limits of agreement ranged from 0.553 to - 0.719 kPa. The difference was ?0.5 kPa, with a maximum recorded difference of 0.95 kPa. In conclusion, non-invasive carbon dioxide monitoring using a TOSCA monitor is a useful clinical tool in neurology practice. Users should be aware of the possibility of occasional inaccurate readings. A clinically unexpected or incompatible reading should be verified with a blood gas analysis, especially when a decision to provide ventilatory support is required.  相似文献   
966.
ABSTRACT: Sigmoid volvulus is a rare surgical complication occurring in pregnancy and puerperium. Only 84 cases of sigmoid volvulus in pregnancy have been reported in the English literature so far. We have reviewed the available literature on this subject and present another case recently managed at our institution. The available literature suggests that over the years, there has been an improvement in the maternal and fetal outcome for this critical condition, but delay in presentation and a further delay in diagnosis remain a challenge for the treating physicians. Our patient was a 30-week pregnant lady, who presented late with 6?days history of abdominal pain, distension and absolute constipation. She had evidence of multi-organ dysfunction at presentation due to complicated sigmoid volvulus. She was resuscitated and surgical exploration revealed gangrenous large bowel. Bowel resection with diverting ileostomy was performed, but she succumbed to the septic shock due to late presentation. Acute surgical pathology may be overlooked in pregnant patients due to reluctance in radiological workup and a high index of suspicion is essential for enhanced outcome. There is a need to increase the awareness amongst the obstetricians and general practitioners. Early diagnosis and referral and timely surgical intervention could significantly improve the outcome of this surgical and obstetric catastrophe.  相似文献   
967.
blaNDM genes, encoding metallo-β-lactamases providing resistance to carbapenems, have been reported in many locations since the initial report in 2008, including in several Enterobacteriaceae isolates in Australia/New Zealand. Here, we compare 4 additional carbapenem-resistant Klebsiella pneumoniae carrying blaNDM-1 isolated in Australia. Two are sequence type ST147, previously associated with blaNDM in Australia and elsewhere. They carry blaNDM-1 and different 16S rRNA methylase genes (armA or rmtC) on different conjugative plasmids, in 1 case with an IncFIIY replicon. One isolate belongs to the globally important ST11 but did not transfer a plasmid to Escherichia coli. The fourth isolate belongs to the novel ST1068 and transferred blaNDM-1, armA, and an IncA/C plasmid. Amplification and sequencing of ompK porin genes suggest that, unlike the case for other carbapenemase genes, ompK36 defects may not be required for NDM to cause clinically relevant levels of carbapenem resistance.  相似文献   
968.
Fallopian tube torsion is a rare but important cause of acute pelvic pain in young adolescent girls. It is a surgical emergency treated with either detorsion or salpingectomy. The imaging findings can be nonspecific and challenging. However, an accurate early diagnosis is essential for prompt surgical treatment. Our objective was to review whether imaging findings can be specific enough to suggest the diagnosis of tubal torsion prospectively in the appropriate clinical setting. An Institutional Review Board–approved retrospective review of our imaging database from 2005 to 2012 revealed 10 surgically proven cases of fallopian tube torsion. All cases had sonography performed; 5 cases had additional multidetector computed tomography. All 10 patients (9–17 years) presented with acute pelvic pain. Sonographic findings included dilated tubular structures in 6 of 10 cases: adjacent to a normal ipsilateral ovary in 5 of 6 and adjacent to a benign ovarian teratoma in 1. In 4 cases, no dilated tube was identified; 3 of 4 had a cystic mass separate from the ovaries, and 1 had the imaging appearance of a multicystic ovary. Computed tomographic findings in the 5 cases that underwent multidetector computed tomography included a dilated tubular structure in 3 of 5; 2 of 5 had a cystic adnexal mass identified. Although rare, tubal torsion should be considered in female adolescents with acute pelvic pain. Sonography should be the first imaging choice. When a tubular structure or a midline cystic mass associated with a normal ipsilateral ovary is noted, tubal torsion should be considered in the differential diagnosis.  相似文献   
969.
Chronic hyperglycemia impairs insulin action, resulting in glucotoxicity, which can be ameliorated in animal models by inducing glucosuria with renal glucose transport inhibitors. Here, we examined whether reduction of plasma glucose with a sodium-glucose cotransporter 2 (SGLT2) inhibitor could improve insulin-mediated tissue glucose disposal in patients with type 2 diabetes. Eighteen diabetic men were randomized to receive either dapagliflozin (n = 12) or placebo (n = 6) for 2 weeks. We measured insulin-mediated whole body glucose uptake and endogenous glucose production (EGP) at baseline and 2 weeks after treatment using the euglycemic hyperinsulinemic clamp technique. Dapagliflozin treatment induced glucosuria and markedly lowered fasting plasma glucose. Insulin-mediated tissue glucose disposal increased by approximately 18% after 2 weeks of dapagliflozin treatment, while placebo-treated subjects had no change in insulin sensitivity. Surprisingly, following dapagliflozin treatment, EGP increased substantially and was accompanied by an increase in fasting plasma glucagon concentration. Together, our data indicate that reduction of plasma glucose with an agent that works specifically on the kidney to induce glucosuria improves muscle insulin sensitivity. However, glucosuria induction following SGLT2 inhibition is associated with a paradoxical increase in EGP. These results provide support for the glucotoxicity hypothesis, which suggests that chronic hyperglycemia impairs insulin action in individuals with type 2 diabetes.  相似文献   
970.
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