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41.
After establishing a foothold in the West, the pandemic of obesity now threatens to spin out of control in the developing nations of Asia and the Indian subcontinent. Like many of its neighbors, Pakistan has witnessed an unprecedented growth in the number of overweight and obese individuals in its population, and obesity is proving to be an issue of considerable public health concern. Conventional medical therapies for obesity and related complications have proven to be less than effective, especially in the population of the southeast, which appears to be inherently predisposed to developing obesity‐related complications. Bariatric surgery is fast emerging as a definitive therapeutic alternative for obesity and has proven to be highly successful and cost‐effective at producing remission of complications of the same. In this article, we expound the need for introducing and incorporating bariatric surgery as part of the therapeutic protocols for obese individuals of South Asian descent suffering from the chronic and debilitating complications of obesity. 相似文献
42.
Conjunctival flap advancement with or without scleral graft for hypotony maculopathy after trabeculectomy 下载免费PDF全文
AIM: To introduce a novel technique for transscleral fixation of the PC-IOL that requires no sutures on the IOL haptics. METHODS: Instead of suturing polypropylene onto the IOL haptics, the method simply winds the thread on the haptics. Fifteen eyes of 15 patients underwent this technique and were followed up for more than 18 months. Surgical outcomes and post-operative complications were evaluated and compared with those of the conventional transscleral fixation method. RESULTS: Postoperative cylinder was significantly lower in the thread winding group than in the conventional transscleral fixation method group (-1.02±0.46 diopters vs -1.57±0.77 diopters; P=0.01). Further, no postoperative complications, such as optic capture, IOL dislocation, and hyphema, were detected in the thread winding group. CONCLUSION: We believe that our thread winding technique is better than previously reported methods because it is simple, mechanically stable, and free from suture-related complications. 相似文献
43.
Amir Tejani Ping Leung Ho Lea Emmett Donald M Stablein 《American journal of transplantation》2002,2(2):142-147
Chronic rejection accounted for 32% of all graft losses in 7123 pediatric transplants. In a previous study acute, multiple acute and late acute rejections were risk factors for the development of chronic rejection. We postulated that the recent decrease in acute rejections would translate into a lower risk for chronic rejection among patients with recent transplants. We reviewed our data on patients transplanted from 1995 to 2000, and using multivariate analysis and a proportional hazards model developed risk factors for patients whose grafts had failed due to chronic rejection. A late initial rejection increased the risk of chronic rejection graft failure 3.6-fold (p < 0.001), while a second rejection resulted in further increase of 4.2-fold (p < 0.001). Recipients who received less than 5 mg/kg of cyclosporine at 30 days post-transplant had a relative risk (RR) of 1.9 (p = 0.02). Patients transplanted from 1995 to 2000 had a significantly lower risk (RR = 0.54, p < 0.001) of graft failure from chronic rejection than those who received their transplants earlier (1987-94). Since we were able to demonstrate that there is a decreased risk of chronic rejection graft failure in our study cohort, we would conclude that the goal of future transplants should be to minimize acute rejections. 相似文献
44.
Abu Abeid S Szold A Gavert N Goldiner I Grynberg E Peretz H Konikoff FM 《Obesity surgery》2002,12(3):354-357
Background: Obesity and especially rapid weight loss following bariatric surgery are known risk factors for cholelithiasis.
Since the risk may be high, prophylactic cholecystectomy has been advocated. Apolipoprotein (Apo) E, an important carrier
protein in cholesterol metabolism and trafficking, is believed to play a role in gallstone pathogenesis. In particular, the
Apo E4 allele has been suggested to be associated with cholesterol cholelithiasis. The aim of this study was to assess the
incidence of postoperative cholelithiasis in our patient population and to determine a possible correlation with the Apo-E
genotype. Methods: 134 morbidly obese patients undergoing gastric restrictive surgery [laparoscopic assisted gastric banding
(LAGB) or silastic ring vertical gastroplasty (SRVG)] had abdominal ultrasound before and 6 to 12 months after operation,
to determine the presence of gallstones. None of the patients enrolled in the study had gallstones before surgery.They did
not have a prophylactic cholecystectomy or receive bile salt treatment. Apo-E genotypes were determined by Polymerase Chain
Reaction restriction enzyme analysis. Results: 10 patients (7.5%) developed postoperative cholelithiasis. The incidence of
cholelithiasis in each ApoE genotype was: E2/E3 - 1/20 (5%), E3/E3 - 3/91 (3%), E3/E4 - 6/21 (29%), and E4/E4 - 0/2. ApoE
allele frequencies in the study population were identical to those of a healthy control population. The mean BMI dropped from
43.6 to 29.4 kg/m2. Conclusions: The occurrence of postoperative gallstones was low in our population. However, in subjects with the Apo-E3/E4
genotype, the incidence is of practical significance. These data suggest that Apo-E genotyping may be useful in selecting
patients for gallstone prevention (surgical or medical) when undergoing bariatric surgery.Further testing in larger patient
populations may be able to give more definite guidelines in the future. 相似文献
45.
Abrishami S Karami M Karimi A Soufali AP Aslani HR Badizadeh K 《Journal of children's orthopaedics》2010,4(2):137-141
Background
Balanced forces around the hip joint are critical for normal development of the hip joint, so it should be considered in every hip reconstructive procedure. 相似文献46.
Gilboa A Winocur G Rosenbaum RS Poreh A Gao F Black SE Westmacott R Moscovitch M 《Hippocampus》2006,16(11):966-980
Lesions restricted to the hippocampal formation and/or extended hippocampal system (hippocampal formation, fornix, mammillary bodies, and anterior thalamic nuclei) can disrupt conscious recollection in anterograde amnesia, while leaving familiarity-based memory relatively intact. Familiarity may be supported by extra-hippocampal medial temporal lobe (MTL) structures. Within-task dissociations in recognition memory best exemplify this distinction in anterograde amnesia. The authors report for the first time comparable dissociations within recognition memory in retrograde amnesia. An amnesic patient (A.D.) with bilateral fornix and septal nuclei lesions failed to recognize details pertaining to personal past events only when recollection was required, during recognition of episodic details. His intact recognition of generic and semantic details pertaining to the same events was ascribed to intact familiarity processes. Recollective processes in the controls were reflected by asymmetrical Receiver's Operating Characteristic curves, whereas the patient's Receiver's Operating Characteristic was symmetrical, suggesting that his inferior recognition performance on episodic details was reliant on familiarity processes. Anterograde and retrograde memories were equally affected, with no temporal gradient for retrograde memories. By comparison, another amnesic person (K.C.) with extensive MTL damage (involving extra-hippocampal MTL structures in addition to hippocampal and fornix lesions) had very poor recognition and no recollection of either episodic or generic/semantic details. These data suggest that the extended hippocampal system is required to support recollection for both anterograde and retrograde memories, regardless of their age. 相似文献
47.
In humans, hyperbaric pressure induces the high-pressure neurological syndrome (HPNS). HPNS is characterized by tremor, sleep disorders, electroencephalographic changes, and impairment of cognitive and motor performances. In animals, higher pressures result in convulsions and death. An increased N-methyl-d-aspartate receptor (NMDAR) response has been implicated with HPNS. We studied high-pressure effects on pharmacologically isolated NMDAR field excitatory postsynaptic potentials (fEPSPs). Hippocampal coronal brain slices from male Sprague-Dawley rats were prepared, constantly superfused with physiological solutions, gas-saturated at normobaric pressure and compressed up to 10.1 MPa with helium. fEPSPs were recorded from the dendritic layer of CA1 pyramidal neurones. High pressure significantly increased the single fEPSP delay, maximal initial slope, amplitude, decay time and time integral (elevated Na(+) and Ca(2+) influx) despite the known general decrease in glutamatergic synaptic release. The estimated negative and positive activation volumes (DeltaV*) for various kinetic segments of the fEPSP suggest a complex response of the receptor to pressure. The NMDAR frequency response was tested by a train of five stimuli. At 50-100 Hz, high pressure did not increase the fEPSPs' frequency-dependent depression and the train's time integral remained unchanged. At 25 Hz, pressure induced a larger frequency-dependent depression and significantly increased the time integral. Our results provide, for the first time, direct information on the isolated brain NMDAR response under hyperbaric conditions. These observations may explain some increase in the excitability of single normal glutametergic fEPSPs and their frequency responses. 相似文献
48.
49.
50.
Biomechanical evaluation of paracoccygeal transsacral fixation 总被引:1,自引:0,他引:1
STUDY DESIGN: This is a biomechanical study using human cadaveric lumbar spine. OBJECTIVE: To evaluate the biomechanics of paracoccygeal transsacral rod fixation. SUMMARY OF BACKGROUND DATA: Various types of transsacral fixation either by posterior and paracoccygeal approaches have been described in the literature. The biomechanical advantage of transsacral rod fixation is the preservation of supporting structures at L5-S1 level. No biomechanical data on human cadavers have been reported in the literature. The aim of this study is to evaluate the biomechanics of the transsacral rod fixation. METHODS: Six fresh human cadaveric L5-S1 motion segments (mean age 67.5 y; range 46 to 82 y ) were used in the study. Unconstrained and nondestructive pure moments in axial torsion (AT), lateral bending (LB), and flexion-extension (FE) were applied to each specimen after applying transsacral rod and after additional augmentation methods, including bilateral screws, facet screws, and pedicle screw and rod system. Range of motion (ROM) was calculated for each surgical treatment. The disc space was measured with lateral plain radiographs of intact specimens and after transsacral rod insertion to evaluate the amount of distraction. RESULTS: The mean ROM of the intact specimens was 3.5, 6.4, and 11.0 degrees in AT, LB, and FE, respectively. Standalone transsacral rod reduced ROM more than 40% compared with the intact condition (P=0.002). Bilateral screws further reduced the ROM in AT (64%) and LB (70%), but not in FE (53%). Both facet screws and pedicle screw and rod system achieved high construct stability under all loading conditions. The transsacral rod augmented with facet screws reduced ROM by 70%, 80%, and 90% compared with the intact condition. When augmented with pedicle screw and rod system, the transsacral rod reduced ROM by 73%, 87%, and 88% in AT, LB, and FE, respectively. There was no statistical difference between these 2 facet screws and pedicle screw and rod system (P>0.8). CONCLUSIONS: Transsacral rod fixation provides strong ligamentotaxis due to intact annulus. Standalone transsacral rod is able to reduce ROM significantly and achieve indirect decompression by distracting L5-S1 disc space. However, additional posterior fixation, such as facet screws or pedicle screws, is required to achieve better construct stability for successful fusion. 相似文献