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11.
A survey was conducted among the 1990 members of the Vitreous Society in order to measure their acceptance of pneumatic retinopexy. They were asked which treatment they would prefer should they suffer a hypothetical detachment. The choices were limited to pneumatic retinopexy or scleral buckling (encircling or segmental). The majority of respondents selected a scleral buckling procedure for a phakic retinal detachment with two adjacent superior temporal quadrant tears. Surgeons who had been in practice for 10 years or less (median for entire group = 10 years) were significantly more likely to select a pneumatic retinopexy procedure. As the details of the hypothetical detachment became more complicated with myopia, additional tears, vitreous hemorrhage, or lattice degeneration with a positive family history, the respondents selected a scleral buckling procedure with greater frequency, and the differences between the choices of the surgeons became nonsignificant. This survey shows that many surgeons feel pneumatic retinopexy is an acceptable alternative to buckling surgery in select cases. There were no trends by geographic location. 相似文献
12.
Doris Chibo Anne Mijch Richard Doherty Christopher Birch 《Journal of clinical virology》2002,25(2):165-170
BACKGROUND: Mutations in the thymidine kinase (TK) and DNA polymerase (pol) genes of herpes simplex virus (HSV) may confer resistance to antiviral drugs, particularly in the context of immunosuppression induced by infection with the human immunodeficiency virus (HIV). OBJECTIVES: To characterise the HSV type 2 (HSV-2) TK and DNA pol genes in an immunocompromised patient with clinical resistance to both acyclovir and foscarnet. STUDY DESIGN: The TK and DNA pol genes of isolates obtained over a 2-year period from an AIDS patient with severe genital herpes infection were characterised both phenotypically and genotypically. RESULTS: HSV strains that were acyclovir resistant/foscarnet sensitive, acyclovir sensitive/foscarnet sensitive and acyclovir resistant/foscarnet resistant were isolated during this time. The TK gene of all the acyclovir resistant isolates contained a large 969 bp deletion which extended into a downstream untranslated region. The foscarnet resistance was associated with an S725G mutation in a conserved region (region II) of the herpesvirus DNA pol gene. CONCLUSIONS: Clinical and virological suppression of the infection was not always associated with subsequent reactivation with wild-type virus. Mutations of the nature we describe have not previously been reported occurring simultaneously in HSV strains isolated from patients treated with acyclovir and foscarnet. 相似文献
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R L Weinsier L D James B E Darnell N H Wooldridge R Birch G R Hunter A A Bartolucci 《The American journal of clinical nutrition》1992,56(1):44-49
The separate effects of energy restriction and weight loss on serum lipids were studied in 24 postmenopausal moderately obese women before and after weight loss of greater than 10 kg to normal weight. Fasting serum triglycerides (TGs), total cholesterol (TC), high-density-lipoprotein (HDL) and low-density-lipoprotein (LDL) cholesterol, and insulin were measured at the end of four 10-d in-hospital phases, two before and two after weight loss: phase I, stable weight; phase II, 3350 kJ/d(800 kcal/d), followed by outpatient weight loss; phase III, 3350 kJ/d (800 kcal/d); and phase IV, stable weight. Diet composition and exercise were constant the entire study. Energy-restriction effect was determined by comparing average values in stable-weight phases (I and IV) with low-energy phases (II and III); weight-loss effect was determined by comparing values in obese phases (I and II) with reduced-weight phases (III and IV). Energy restriction lowered TG, TC, LDL cholesterol, the LDL-HDL cholesterol ratio, and insulin and raised HDL cholesterol (all P less than 0.05). Weight loss lowered TG, TC, LDL cholesterol, and insulin (all P less than 0.01) but did not change HDL cholesterol or the LDL-HDL cholesterol ratio. The results suggest that reduction to a weight-steady nonobese state significantly lowers TG, TC, and LDL cholesterol but does not improve HDL cholesterol or the LDL-HDL cholesterol ratio. 相似文献
16.
Elisa Faybush David C Mulligan Barry D Birch Joseph I Sirven Vijayan Balan 《Liver transplantation》2005,11(4):467-468
There are no published accounts of patients with ventriculoperitoneal shunts undergoing liver transplantation in the literature. Because patients with ventriculoperitoneal shunts are prone to infections, this may be a theoretical contraindication to transplantation. We present a case of a patient with cirrhosis who had a ventriculoperitoneal shunt placed many years prior to transplantation. The patient had no neurological complications and the shunt was intact and functioning. Prior to transplantation, the patient underwent a ventriculoperitoneal to ventriculopleural shunt conversion that was reversed posttransplantation. Apart from some minor complications, the patient has done remarkably well from a graft and neurological perspective. In conclusion, patients who have ventriculoperitoneal shunts may be considered for liver transplantation as the risk of infectious and neurological complications is low and there are no deleterious effects on graft survival. 相似文献
17.
Daniel W. Birch 《Canadian journal of surgery》2007,50(3):195-201
INTRODUCTION: Laparoscopic repair of ventral and incisional hernias (LVIHRs) is feasible; however, many facets of this procedure remain poorly defined. The indications, essential technical features and postoperative management should be standardized to optimize outcomes and facilitate training in this promising approach to incisional hernia repair. METHODS: All patients referred to one surgeon at a tertiary care centre for LVIHR from 1999 to 2004 were analyzed. Patient records were analyzed and perioperative outcomes were documented. RESULTS: Of the 69 patients who were referred for management of incisional hernia, 64 underwent LVIHR. The mean age of patients selected for surgery was 61.4 years (28% of patients over age 70 years); their mean body mass index (BMI) was 32.8 kg/m2 and mean American Association of Anaesthetists (ASA) score was 2.5 (52% of patients had an ASA score equal to 3). The mean operating time was 130.7 minutes for a mean abdominal wall defect of 123.9 cm2 and a mean prosthetic mesh size of 344 cm2. Patients with recurrent incisional hernias and previous prosthetic mesh were the most challenging, with a mean BMI of 39 kg/m2, mean operating time of 191 minutes, mean defect of 224 cm2 and mean prosthetic mesh size of 508 cm2. One patient was converted to open surgery and, in 2 patients, small bowel injuries were repaired laparoscopically without adverse sequelae. The mean length of stay was 4.5 days (median 3.0 d). Postoperatively, 78% of patients developed seromas within the residual hernia sac. All seromas were managed nonoperatively; one-half resolved by 7 weeks, and larger seromas persisted for up to 24 weeks. There was an 18.7% rate of minor complications and a 3.1% rate of major complications (no deaths). After a mean follow-up of 7.7 months, 2 recurrent hernias (3.1%) were identified in patients with multiple previous open mesh repairs. CONCLUSION: Although LVIHR may be challenging, it has the potential to be considered a primary approach for most ventral and incisional hernias, regardless of patient status or hernia complexity. 相似文献
18.
Nadim Aslam Stephen Gwilym Christos Apostolou Nicholas Birch Rajan Natarajan William Ribbans 《European journal of emergency medicine》2004,11(3):148-150
OBJECTIVES: To illustrate the types of injuries seen by the accident and emergency department as a result of the use of non-motorized 'microscooters' in children, and to increase awareness of scooter-related triplane fractures of the ankle. STUDY DESIGN: A retrospective study conducted in an accident and emergency department of a district general hospital on all children who had a scooter-related limb injury over a 6-month period and were referred for orthopaedic review. METHODS: The analysis involved a case note review. Information recorded included the injury sustained, protective equipment worn at the time of the accident and management by the orthopaedic team. RESULTS: Scooter injuries accounted for 10 fractures in this period. There were three 'triplanar' injuries, which required operative fixation, and three injuries requiring manipulation under anaesthesia. No protective gear was worn by any of the patients. CONCLUSION: The popularity of microscooters seems to represent a significant risk of bony injury in the paediatric population. Medical personnel who manage acute paediatric trauma should be aware of scooter-related triplanar ankle injuries. 相似文献
19.
PURPOSE: To review what is known about the normal maturational sequence for fusion and stereopsis and the binocular sensory deficits associated with accommodative esotropia (ET) and to explore the clues that accommodative ET provides about critical periods for binocular sensory function. METHODS: Studies of binocular sensory function during infancy and early childhood are presented. RESULTS: Most of the maturation of binocular sensory function occurs during the first year of life, yet a later abnormal visual experience-such as the onset of accommodative ET--can profoundly and permanently disrupt fusion and stereopsis. CONCLUSIONS: Some binocular sensory deficits may exist before the onset of accommodative ET, but others may result directly from abnormal binocular experience. The functional organization of the maturing visual system appears to be maximally sensitive to disruption by abnormal visual experience during the first months of life, but susceptibility continues until at least 4 years of age. 相似文献
20.
Utility of a multiplex PCR assay for detecting herpesvirus DNA in clinical samples 总被引:4,自引:0,他引:4
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Druce J Catton M Chibo D Minerds K Tyssen D Kostecki R Maskill B Leong-Shaw W Gerrard M Birch C 《Journal of clinical microbiology》2002,40(5):1728-1732
A multiplex PCR was designed to amplify herpes simplex virus types 1 and 2, cytomegalovirus, and varicella-zoster virus DNA present in a diverse range of clinical material. The susceptibility of these viruses to in vivo inhibition by at least one antiviral drug was an important consideration in their inclusion in the multiplex detection system. An aliquot of equine herpesvirus was introduced into each specimen prior to extraction and served as an indicator of potential inhibitors of the PCR and a detector of suboptimal PCR conditions. Compared to virus isolation and immunofluorescence-based antigen detection, the multiplex assay yielded higher detection rates for all viruses represented in the assay. The turnaround time for performance of the assay was markedly reduced compared to those for the other techniques used to identify these viruses. More than 21,000 tests have been performed using the assay. Overall, the multiplex PCR enabled the detection of substantially increased numbers of herpesviruses, in some cases in specimens or anatomical sites where previously they were rarely if ever identified using traditional detection methods. 相似文献