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71.
BACKGROUND: To study the mortality among morbidly obese patients qualifying for bariatric surgery. Mortality from bariatric surgery for morbid obesity has been widely reported; however, little is known about the mortality in morbidly obese patients who defer surgery. METHODS: Consecutive patients evaluated for bariatric surgery with an initial encounter between 1997 and 2004 were identified. The Social Security Death Index and office records were used to identify mortality through 2006. We conducted telephone interviews to determine whether the 305 patients who did not undergo bariatric surgery at our institution had undergone the surgery elsewhere. Using Cox proportional hazards models, we compared the mortality in patients undergoing surgery with that of those who did not. To evaluate bias resulting from missing data, we conducted analyses assuming that all patients with missing data had (1) undergone surgery and (2) not undergone surgery. RESULTS: A total of 908 patients underwent bariatric surgery (880 patients at our institution and 28 patients elsewhere). A total of 112 patients did not undergo surgery. Data regarding surgery on 165 patients could not be obtained. The mortality in those patients who did not undergo surgery was 14.3% compared with 2.9% for those who did undergo surgery. Adjusting for age, gender, and body mass index, patients who had undergone surgery had an 82% reduction in mortality (hazard ratio 0.18, 95% confidence interval 0.09-0.35, P <.0001). Sensitivity analysis, assuming that all patients with missing data received surgery resulted in an 85% mortality reduction (P <.001) and assuming that patients did not receive surgery resulted in a 50% mortality reduction (P = .04). CONCLUSIONS: Mortality among morbidly obese patients without surgery was 14.3% during the study period. Surgical intervention offered a 50%-85% mortality reduction benefit.  相似文献   
72.
The purpose of this study is to evaluate the effectiveness of a shorter course of Dialectical Behavior Therapy (DBT) in enhancing treatment retention and reducing: urges to engage in non-suicidal self injury (NSSI), NSSI, suicide ideation, and subjective distress in borderline personality disorder (BPD). Twenty patients with BPD received a six-month course of Dialectical Behavior Therapy (DBT-B). DBT-B was delivered in the standard manner except for the shortened duration from one-year minimum to six months. All variables were measured at baseline, and at six months. Data were analyzed using paired t-tests. Treatment retention rate was 95%. Significant reductions were found in NSSI urges, NSSI, suicide ideation, subjective distress, depression, and hopelessness between baseline and six months. These results support the use of DBT-B in a six-month format when NSSI and suicidal behavior and ideation are the targeted behaviors. Target behaviors were reduced significantly and retention was extremely high in comparison to other interventions for this population. A large scale randomized controlled trial investigating its efficacy is warranted to determine if the results can be replicated and if improvement can be sustained.  相似文献   
73.
74.
Angiogenesis precedes recovery following spinal cord injury and its extent correlates with neural regeneration, suggesting that angiogenesis may play a role in repair. An important precondition for studying the role of angiogenesis is the ability to induce it in a controlled manner. Previously, we showed that a coculture of endothelial cells (ECs) and neural progenitor cells (NPCs) promoted the formation of stable tubes in vitro and stable, functional vascular networks in vivo in a subcutaneous model. We sought to test whether a similar coculture would lead to the formation of stable functional vessels in the spinal cord following injury. We created microvascular networks in a biodegradable two-component implant system and tested the ability of the coculture or controls (lesion control, implant alone, implant + ECs or implant + NPCs) to promote angiogenesis in a rat hemisection model of spinal cord injury. The coculture implant led to a fourfold increase in functional vessels compared with the lesion control, implant alone or implant + NPCs groups and a twofold increase in functional vessels over the implant + ECs group. Furthermore, half of the vessels in the coculture implant exhibited positive staining for the endothelial barrier antigen, a marker for the formation of the blood–spinal cord barrier. No other groups have shown positive staining for the blood–spinal cord barrier in the injury epicenter. This work provides a novel method to induce angiogenesis following spinal cord injury and a foundation for studying its role in repair.  相似文献   
75.
76.
The aim of this study was to describe and quantify systemic antibiotic prescribing for patients with chronic skin wounds presenting at the primary care, nonspecialist setting. Data for 1 year were extracted from a general practice morbidity database comprising approximately 185,000 patients attending family medical practitioners in Wales. Patients with chronic wounds (PCW) were identified using Read Codes and compared with nonwound patients who were randomly selected after matching for age-band, sex, and general practice. PCW received a significantly greater number of antibiotic courses than nonwound patients (p<0.001). This increased level of prescribing was evident for flucloxacillin, co-amoxiclav, cefaclor, cefalexin, erythromycin, trimethoprim, metronidazole, and ciprofloxacin (p<0.01 for all). While PCW also had a significantly higher prevalence of diabetes (16.5% compared with 6.6%, p<0.001), and attended at general practice significantly more frequently than nonwound patients (median (interquartile range) of 25 (17-40) visits per year compared with 12 (4-20), p<0.001), importantly, exclusion of diabetic patients and analysis of the proportion of visits on which patients received antibiotics did not affect the significance of the difference in antibiotic consumption. These data show a strong association between occurrence of chronic wounds and prescribing of antibiotics in primary health care, and wide variation in the type and duration of antibiotic therapy for chronic wounds. Further work is now indicated to rationalize this prescribing and determine the role that this exposure to antibiotics plays in the prevalence of antibiotic resistance in this at-risk elderly population.  相似文献   
77.
Background/Aims: This study was designed to assess changes in: (a) neuropsychological tests, measures of memory, quality of life and scores for anxiety and depression; (b) liver function tests; and (c) the relationship between these following transjugular intrahepatic portosystemic stent-shunt.Methods: Twenty-nine patients undergoing transjugular intrahepatic portosystemic stent-shunt for recurrent variceal haemorrhage, 12 matched patients with cirrhosis and variceal haemorrhage manage with variceal band ligation and 16 normal controls were studied. Patients in any of the groups who were clinically encephalopathic were excluded from the study. Serial changes in the conventional liver function tests and Indocyanine green clearance, and psychometric function (Hospital Anxiety Depression Scale, Rivermead Behavioral Memory Test, Quality of Life and the memory and reaction sub-tests of the Cambridge Automated Neuropsychological Test Assessment Battery) were measured prior to and 1, 3, 9 and 15 months following transjugular intrahepatic portosystemic stent-shunt.Results: Over a mean follow up of 9.1 months in the transjugular intrahepatic portosystemic stent-shunt group (range 3–28), one patient (3%) developed clinically detectable encephalopathy. Sixty-seven percent of patients with cirrhosis showed evidence of subclinical encephalopathy as compared with the control population. Significant deterioration occurred in the reaction sub-tests of the Cambridge Automated neuropsychological Test Assessment Battery in patients, both in the transjugular intrahepatic portosystemic stent-shunt group and the controls with cirrhosis, during follow up. Transjugular intrahepatic portosystemic stent-shunt was followed by significant deterioration in levels of anxiety and psychological component of the quality of life. The Rivermead Behavioural Memory Test and the memory sub-test of the Cambridge Automated Neurpsychological Test Assessment Battery did, however, improve significantly at 1 and 15 months after transjugular intrahepatic portosystemic stent-shunt, respectively. Serum alanine aminotransferase, bilirubin and indocyanine green clearance deteriorated significantly following transjugular intrahepatic portosystemic stent-shunt (p<0.001, p<0.001 and p<0.0001, respectively). Significant correlation was observed between changes in the indocyanine green clearance and changes in the complex and simple reaction time subtests of the Cambridge Automated Neuropsychological Test Assessment Battery (r=0.6 and r=0.66, respectively).Conclusions: The results of this study showed that about 67% of patients with cirrhosis were subclinically encephalopathic and that temporary deterioration occurred in the Cambridge Automated Neuropsychological Test Assessment Battery during follow up, both in patients having transjugular intrahepatic portosystemic stent-shunt and in the controls with cirrhosis. These parallel the changes in the liver function tests and indocyanine green clearance. Temporary deterioration was also observed in the Quality of Life and Hospital Anxiety Depression Scale in the transjugular intrahepatic portosystemic stent-shunt group, although the measures of memory improved. Further studies should address the biochemical mechanisms of these changes and the role of prophylactic measures.  相似文献   
78.
This work describes the design and construction of a device that facilitates the loading of DNA samples onto polyacrylamide gels for detection in the Perkin Elmer/Applied Biosystems (PE/ABI) 373 and 377 DNA sequencing instruments. The device is mounted onto the existing gel cassettes and makes the process of loading high-density gels less cumbersome while the associated time and errors are reduced. The principle of operation includes the simultaneous transfer of the entire batch of samples, in which a spring-loaded air cylinder generates positive pressure and flexible silica capillaries transfer the samples. A retractable capillary array carrier allows the delivery ends of the capillaries to be held up clear of the gel during loader attachment on the gel plates, while enabling their insertion in the gel wells once the device is securely mounted. Gel-loading devices capable of simultaneously transferring 72 samples onto the PE/ABI 373 and 377 are currently being used in our production sequencing groups while a 96-sample transfer prototype undergoes testing.  相似文献   
79.
The anucleate (distal) segment of a crayfish medial giant axon (MGA) remains intact for months in vivo after severing the axon from its cell body, a phenomenon referred to as long-term survival (LTS). We collected axoplasm from chronic anucleate MGAs by perfusing 2-cm lengths of axons with an intracellular saline. This axoperfusate was analyzed by SDS-PAGE and silver stained. Axoperfusate proteins from intact MGAs and from chronic anucleate MGAs exhibiting LTS for up to 6 months were the same. Furthermore, immunoreactive levels of actin and β-tubulin were similar in axoperfusates from intact and chronic anucleate MGAs. This maintenance of proteins in chronic anucleate MGAs must be due to a lack of protein degradation and/or to local protein synthesis by a source other than the cell body. To investigate local protein synthesis in vitro, we added [35S]-methionine to the extracellular saline surrounding intact and chronic anucleate MGAs. After 4- to 6-h incubations, radiolabelled proteins were detected in axoperfusates analyzed by SDS-PAGE and fluorography. The similarity between radiolabelled proteins in axoperfusates and MGA glial sheaths indicated a glial origin for the radiolabelled axoperfusate proteins. Various observations and control experiments suggested that glial-axonal protein transfer occurred by a physiological process. Glial-axonal protein transfer may contribute to the maintenance of proteins during LTS of chronic anucleate MGAs.  相似文献   
80.
2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) causes cardiovascular toxicity in laboratory animals, including alteration in several processes in which beta-adrenergic receptor (beta-AR) signaling plays important roles. Thus, our laboratory investigated the effects of TCDD on beta-AR expression and signal transduction. Fertile chicken eggs were injected with vehicle (corn oil), 0.24 or 0.3 pmol TCDD/g egg on incubation day 0 (D0) or D5. On D10, heart function was assessed by ECG in ovo. Exposure to TCDD increased the incidence of arrhythmias and decreased the positive chronotropic responsiveness of the heart to isoproterenol. The reduced beta-AR responsiveness was, in part, independent of any overt morphological changes in the heart as chick embryos exposed to TCDD on D5 displayed an intermediate responsiveness to beta-AR agonist in the absence of the dilated cardiomyopathy observed in chick embryos exposed to TCDD on D0. TCDD did not decrease the chronotropic response of the heart to agents that stimulate signals downstream of the beta-AR. In fact, TCDD-exposed embryos were more sensitive than controls to forskolin, increasing heart rates (HR) 21.8 +/- 3.5 beats per min (bpm) above baseline versus control values at 6.3 +/- 2.7 bpm above baseline. TCDD exposure also augmented the negative chronotropic response of the heart to verapamil, decreasing HR -23.2 +/- 7.4 bpm relative to baseline versus control embryos at -12.7 +/- 5.9 bpm below baseline. Finally, the mean cardiac beta1-AR mRNA expression in D10 embryos was not significantly altered by exposure to TCDD on D0. These findings establish that a functional end point of the developing chick heart is sensitive to TCDD exposure and that the TCDD-induced reduction in beta-AR responsiveness may result from alterations in signal transduction upstream of adenylyl cyclase.  相似文献   
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