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61.
Revision endoscopic frontal sinus surgery with surgical navigation.   总被引:9,自引:0,他引:9  
BACKGROUND: Revision surgery of the frontal sinus remains one of the most difficult operations for the endoscopic surgeon. Most agree that knowledge and recognition of its complex anatomy and sparing of frontal recess mucosa are keys to a successful operation. The use of surgical navigation systems may allow for more precise dissections and greater rates of frontal recess patency. METHODS: Retrospective review of all patients undergoing revision endoscopic frontal sinus surgery with surgical navigation was performed with a minimum 24-month follow-up. RESULTS: Sixty-seven patients underwent revision endoscopic frontal sinus surgery with surgical navigation. The average follow-up was 32 months. Fifty-eight (86.6%) had a patent frontal recess and significant subjective improvement in symptoms. No patient underwent external frontal sinus obliteration, and there were no major complications. CONCLUSIONS: Endoscopic techniques with surgical navigation are effective in revision frontal sinus cases. The dissection of remnant agger nasi, obstructing frontal and supraorbital cells are necessary to widen the anterior-posterior as well as the medial-lateral dimensions of the recess. Computer navigational systems appear to serve as a valuable adjunct in preoperative planning and safe intraoperative dissection.  相似文献   
62.
Civilian helicopter accidents into water: analysis of 46 cases, 1979-2006   总被引:1,自引:0,他引:1  
BACKGROUND: When a helicopter crashes or ditches into water the crew and passengers must often make an escape from underwater and a number of the occupants do not survive. This paper examined fatality rates, human factors problems with escape, and causes of death in Canadian civilian registered helicopter accidents in water (1979-2006). METHOD: Data obtained from the Transportation Safety Board of Canada was reviewed. Key issues such as fatalities, injuries, warning time, sinking, and inversion were examined. RESULTS: There were 46 helicopters that ditched into water. There were 124 crew and passengers involved. Of those, 27 (23%) crew and passengers died. Lack of warning time (55%), rapid sinking (72%), and inversion (35%) were the most common issues in the accidents. CONCLUSION: Survival rates for Canadian registered helicopter accidents into water (78%) show little change from previously reported worldwide data. Lack of warning time, rapid sinking, and inversion were the significant factors in the survival rate. The practical implication is that crew and passengers involved in planned flights over water must wear all the life support equipment on strap-in and not have it stowed on the back of the seat or in the cabin.  相似文献   
63.
OBJECTIVE: To analyze the occurrence of fungal wound infection (FWI) after thermal injury and its relationship to mortality. BACKGROUND: FWI is an uncommon but potentially lethal complication of severe thermal injury. METHODS: The records of patients with thermal burns admitted to a single burn center (1991-2002) were reviewed. Analyses accounted for total burn size (TBS, percentage body surface area), full-thickness burn size (FTBS, percentage body surface area), age, inhalation injury, sex, and fungal-status category. Fungal colonization and infection were determined histopathologically. RESULTS: Criteria for inclusion were met by 2651 patients. Each patient's fungal-status category was defined according to the deepest level of fungal involvement observed during the hospital course: no fungus (2476 patients), fungal wound colonization (FWC, 121 patients), or fungal wound infection (FWI, 54 patients). Median TBS (9%, 47%, 64%, respectively) and mortality (5%, 27%, 76%, respectively) varied significantly among fungal-status groups. Logistic regression was used to detect significant independent associations. FWI was associated with higher TBS. Mortality was associated with TBS, FTBS, inhalation injury, FWI, and age. Unlike FWI, FWC was not independently related to mortality, the greater observed mortality in FWC being explained by other variables such as TBS. The odds ratio for FWI (8.16) suggested about the same mortality impact as augmenting TBS by 33%. A midrange TBS of 30% to 60% was required for most of the detectable association of FWI with mortality. CONCLUSIONS: FWI accompanies larger burns and is associated with mortality in burn patients, particularly in those with TBS 30% to 60%. This association is independent of burn size, inhalation injury, and age.  相似文献   
64.
The aim of this study was to determine if DNA polymorphism within runt-related gene 2 (RUNX2)/core binding factor A1 (CBFA1) is related to bone mineral density (BMD). RUNX2 contains a glutamine-alanine repeat where mutations causing cleidocranial dysplasia (CCD) have been observed. Two common variants were detected within the alanine repeat: an 18-bp deletion and a synonymous alanine codon polymorphism with alleles GCA and GCG (noted as A and G alleles, respectively). In addition, rare mutations that may be related to low BMD were observed within the glutamine repeat. In 495 randomly selected women of the Geelong Osteoporosis Study (GOS), the A allele was associated with higher BMD at all sites tested. The effect was maximal at the ultradistal (UD) radius (p = 0.001). In a separate fracture study, the A allele was significantly protective against Colles' fracture in elderly women but not spine and hip fracture. The A allele was associated with increased BMD and was protective against a common form of osteoporotic fracture, suggesting that RUNX2 variants may be related to genetic effects on BMD and osteoporosis.  相似文献   
65.
A subcuticular suture is an ideal closure method of surgical wounds where the aim is healing by primary intention. The addition of adhesive strips over the subcuticular suture appears to be based on anecdotal, rather than experimental evidence. We performed a prospective study to compare the postoperative wound complications of combination closure with subcuticular closure alone. The wounds of 60 consecutive patients undergoing foot surgery were assessed clinically for wound complications at one week postoperatively. Patients who had a combined closure were more likely to develop wound complications. They were also twice as likely to return to clinic for a further wound check. The addition of adhesive strips to such a closure appears to offer no clinical benefit, and can be detrimental to wound healing. We recommend meticulous closure of surgical wounds with continuous, absorbable, subcuticular suture without adhesive strips, for an optimal outcome.  相似文献   
66.
BACKGROUND AND OBJECTIVE: Imbalance between cerebral oxygen supply and demand is thought to play an important role in the development of cerebral injury during cardiac surgery with cardiopulmonary bypass. METHODS: We studied jugular bulb oxygen saturation, jugular bulb oxygen tension, arterial-jugular bulb oxygen content difference and oxygen extraction ratio in 20 patients undergoing warm coronary artery bypass surgery (34-37 degrees C) with pH-stat blood gas management. RESULTS: Only two patients showed desaturation (jugular bulb oxygen saturation < 50%) at 5 min on bypass, and none from 20 min onwards. Multiple regression models were performed after using bypass temperature, mean arterial pressure, cerebral perfusion pressure, haemoglobin concentration and arterial carbon dioxide tension as independent variables, and arterial-jugular bulb oxygen content difference, jugular bulb oxygen saturation, oxygen extraction ratio and jugular bulb oxygen tension as individual dependent variables. CONCLUSIONS: We found that jugular bulb oxygen saturation, jugular bulb oxygen tension and oxygen extraction ratio are mainly dependent on arterial carbon dioxide tension, and arterial-jugular bulb oxygen content difference is dependent on arterial carbon dioxide tension and the bypass temperature. Our results suggest jugular bulb oxygenation is mainly dependent on arterial carbon dioxide tension during warm cardiopulmonary bypass.  相似文献   
67.
Results of L4-L5 disc excision alone versus disc excision and fusion   总被引:5,自引:0,他引:5  
We evaluated the results of 85 patients having L4-L5 disc excision (52 having disc excision alone, and 33 having disc excision and fusion) using the Smiley-Webster scale at an average follow-up of 7.3 years. Both groups (fusion and nonfusion) were comparable except that the nonfusion group had a significantly higher percentage of patients with a history of chronic back pain and degenerative changes on their initial radiographs. The fusion group had significantly better results compared with the nonfusion group (85% satisfactory results versus 39% satisfactory results). The most common cause of unsatisfactory results in the fusion group was pseudarthrosis (two) while progressive degenerative disc disease (18) and recurrent disc prolapse (eight) were the most common cause of unsatisfactory results in the nonfusion group. The overall reoperation rate was 9.4% (13.5% in the nonfusion group, and 3% in the fusion group.  相似文献   
68.
This prospective study compared 30 patients randomly assigned to either a home exercise program or supervised outpatient physical therapy following arthroscopic partial medial meniscectomy. Their knee functions were assessed at 2, 4, and 8 weeks postoperatively using isokinetic analysis and subjective questionnaires. At each evaluation, the home exercise group performed as well or better than the supervised physical therapy group. There were no statistically significant differences between the two groups. At 4 weeks postoperation, the mean percent deficit in torque (strength) between the affected and unaffected limbs was 22.1% in the supervised rehabilitation group and 22.0% in the home exercise. The percent deficit in terms of endurance was 7.7% in the supervised group and 3.6% in the home group. Similar results were noted with regard to the patients' subjective evaluations of their knee function and ability to resume work and recreational activities. We conclude that a well-planned, unsupervised home exercise knee rehabilitation program can produce equally good postoperative recovery as compared to a supervised outpatient physical therapy regimen in properly selected patients following arthroscopic partial meniscectomy of the knee.  相似文献   
69.

Essentials

  • Endothelial activation initiates multiple processes, including hemostasis and inflammation.
  • The molecules that contribute to these processes are co‐stored in secretory granules.
  • How can the cells control release of granule content to allow differentiated responses?
  • Selected agonists recruit an exocytosis‐linked actin ring to boost release of a subset of cargo.

Summary

Background

Endothelial cells harbor specialized storage organelles, Weibel‐Palade bodies (WPBs). Exocytosis of WPB content into the vascular lumen initiates primary hemostasis, mediated by von Willebrand factor (VWF), and inflammation, mediated by several proteins including P‐selectin. During full fusion, secretion of this large hemostatic protein and smaller pro‐inflammatory proteins are thought to be inextricably linked.

Objective

To determine if secretagogue‐dependent differential release of WPB cargo occurs, and whether this is mediated by the formation of an actomyosin ring during exocytosis.

Methods

We used VWF string analysis, leukocyte rolling assays, ELISA, spinning disk confocal microscopy, high‐throughput confocal microscopy and inhibitor and siRNA treatments to demonstrate the existence of cellular machinery that allows differential release of WPB cargo proteins.

Results

Inhibition of the actomyosin ring differentially effects two processes regulated by WPB exocytosis; it perturbs VWF string formation but has no effect on leukocyte rolling. The efficiency of ring recruitment correlates with VWF release; the ratio of release of VWF to small cargoes decreases when ring recruitment is inhibited. The recruitment of the actin ring is time dependent (fusion events occurring directly after stimulation are less likely to initiate hemostasis than later events) and is activated by protein kinase C (PKC) isoforms.

Conclusions

Secretagogues differentially recruit the actomyosin ring, thus demonstrating one mechanism by which the prothrombotic effect of endothelial activation can be modulated. This potentially limits thrombosis whilst permitting a normal inflammatory response. These results have implications for the assessment of WPB fusion, cargo‐content release and the treatment of patients with von Willebrand disease.
  相似文献   
70.

Objective

To examine associations between antidepressant use and health care utilization in young adults beginning maintenance hemodialysis (HD) therapy.

Patients and Methods

Antidepressant use, hospitalizations, and emergency department (ED) visits were examined in young adults (N=130; age, 18-44 years) initiating HD (from January 1, 2001, through December 31, 2013) at a midwestern US institution. Primary outcomes included hospitalizations and ED visits during the first year.

Results

Depression diagnosis was common (47; 36.2%) at HD initiation, yet only 28 patients (21.5%) in the cohort were receiving antidepressant therapy. The antidepressant use group was more likely to have diabetes mellitus (18 [64.3%] vs 33 [32.4%]), coronary artery disease (8 [28.6%] vs 12 [11.8%]), and heart failure (9 [32.1%] vs 15 [14.7%]) (P<.05 for all) than the untreated group. Overall, 68 (52.3%) had 1 or more hospitalizations and 33 (25.4%) had 1 or more ED visits in the first year. The risk of hospitalization during the first year was higher in the antidepressant use group (hazard ratio, 2.35; 95% CI, 1.39-3.96; P=.001), which persisted after adjustment for diabetes, coronary artery disease, and heart failure (hazard ratio, 1.94; 95% CI, 1.22-3.10; P=.006). Emergency department visit rates were similar between the groups.

Conclusion

Depression and antidepressant use for mood indication are common in young adult incident patients initiating HD and and are associated with higher hospitalization rates during the first year. Further research should determine whether antidepressants are a marker for other comorbidities or whether treated depression affects the increased health care use in these individuals.  相似文献   
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