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81.
Walsh RM  Henderson JM  Vogt DP  Baker ME  O'malley CM  Herts B  Zuccaro G  Vargo JJ  Dumot JA  Conwell DL  Biscotti CV  Brown N 《Surgery》2002,132(4):628-33; discussion 633-4
BACKGROUND: Optimal management of pancreatic cystic neoplasms includes identification and resection of mucinous neoplasms. This study was performed to assess the accuracy of preoperative variables in determining a mucinous lesion. METHODS: Patients referred for a cystic neoplasm were prospectively assessed by presenting symptoms, blinded radiologic review, and endoscopic ultrasound-guided cyst aspirate analysis. Patients who were symptomatic, or had aspirate findings of a mucinous neoplasm were resected. RESULTS: Eighty-seven patients were enrolled over a 22-month period ending in December 2001. There were 56 (64%) women and 31 (36%) men, with a mean age of 63 (27-86) years. Thirty-five (40%) patients were resected including 24 (69%) women and 11 (31%) men with a mean age of 58 years. Twenty-eight (80%) patients who had resection were symptomatic. Specimen histology included 18 (51%) mucinous neoplasms, 8 (23%) serous neoplasms, 4 (11%) ductal or neuroendocrine carcinomas, and 3 (9%) pseudocysts. The positive predictive value (PPV) for cyst-aspirate extracellular mucin (83%) was significant in predicting a mucinous neoplasm (P =.009). No other aspirate variables (amylase, carcinoembryonic antigen, CA15-3, viscosity), or patient characteristics were predictive of final histology. Diagnostic agreement between all 3 radiologists was 8% (P =.98). At a median follow-up of 12 months, no patients who were observed required resection. CONCLUSIONS: Patients with suspected pancreatic cystic neoplasms can be selectively treated on the basis of symptoms and cyst-aspirate mucin analysis. Symptomatic and mucin containing lesions should be resected.  相似文献   
82.
This study examined relationships between combat‐exposed Operation Enduring Freedom/Operation Iraqi Freedom veterans’ experiences related to infidelity during deployment (i.e., indicating that a partner was unfaithful or reporting concern about potential infidelity) and postdeployment mental health, as well as the role of subsequent stress exposure and social support in these associations. The sample consisted of 571 individuals (338 men). There were 128 participants (22.2%) who indicated that their partners were unfaithful during their most recent deployment. Of the remaining 443 participants, 168 (37.8%) indicated that they were concerned that their partners might have been unfaithful. Individuals who indicated that their partners were unfaithful exhibited higher levels of posttraumatic stress symptomatology (β = .08; f2= .18) and depression symptom severity (β = .09; f2 = .14), compared to individuals who did not indicate that their partners were unfaithful. For both men and women, reported infidelity was associated with mental health indirectly via postdeployment life stressors, whereas infidelity concerns were indirectly associated with mental health via postdeployment life stressors for men only. Findings suggested that infidelity can have a significant impact on combat‐exposed veterans’ mental health and highlight the need for additional research on this understudied topic within the military population.  相似文献   
83.
Fifteen patients with bilateral carpal tunnel syndrome underwent surgery using intravenous regional anaesthesia (IVRA) on one hand and local infiltration anaesthesia (LA) on the other. All 30 carpal tunnel releases were performed without complication. Patient tolerance for IVRA and LA was similar. Six patients preferred the LA, eight preferred IVRA and one had no preference. Tourniquet time averaged 16 minutes when LA was used and 24 minutes with IVRA (P<0.05). Use of local anaesthesia allows more expeditious surgery and limits costs, but intravenous regional anaesthesia is recommended if epineurotomy, internal neurolysis or flexor tenosynovectomy are planned.  相似文献   
84.
While stem cells derived from the bone marrow are well-known in clinical medicine, fatty tissue as a source of mesenchymal stem cells is still the subject of recent research. However, adipose-derived stem cells (ASC) are not only harvested less invasively, i.e. via minimally invasive liposuction, but also yield higher numbers of multipotent stem cells. Due to cell-cell interactions and also because of the very favorable secretion profile of growth factors and cytokines ASCs displayed an extraordinary regenerative potential in recent preclinical and clinical applications and achieved a significantly better healing in ischemic muscle, heart, and brain insults and in impaired wound healing. ASCs enhanced regeneration in skeletal tissues such as cartilage or bone. They also revealed immunomodulatory effects and improved the clinical status in immunological diseases. In conclusion ASCs are comparable to bone marrow-derived stem cells concerning possible applications in clinical medicine.  相似文献   
85.
Local cooling is very common after bone and joint surgery. Therefore the knowledge of bone blood flow during local cooling is of substantial interest. Previous studies revealed that hypothermia leads to vasoconstriction followed by decreased blood flow levels. The aim of this study was to characterize if local cooling is capable of inducing reduced blood flow in bone tissue using a stepwise‐reduced temperature protocol in experimental rabbits. To examine bone blood flow we utilized the fluorescent microsphere (FM) method. In New Zealand white rabbits one randomly chosen hind limb was cooled stepwise from 32 to 2°C, whereas the contra lateral hind limb served as control. Injection of microspheres was performed after stabilization of bone and muscle temperature at each temperature level. Bones were removed, dissected and fluorescence intensity was determined to calculate blood flow values. We found that blood flow of all cooled regions decreased relative to the applied external temperature. At maximum cooling blood flow was almost completely disrupted, indicating local cooling as powerful regulatory mechanism for regional bone blood flow (RBBF). Postoperative cooling therefore may lead to strongly decreased bone blood flow values. As a result external cooling has capacity to both diminish bone healing and reduce bleeding complications. © 2013 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31:1820–1827, 2013  相似文献   
86.
Establishing whether men and women tend to express different symptoms of posttraumatic stress in reaction to trauma is important for both etiological research and the design of assessment instruments. Use of item response theory (IRT) can reveal how symptom reporting varies by gender and help determine if estimates of symptom severity for men and women are equally reliable. We analyzed responses to the PTSD Checklist (PCL) from 2,341 U.S. military veterans (51% female) who completed deployments in support of operations in Afghanistan and Iraq (Operation Enduring Freedom/Operation Iraqi Freedom [OEF/OIF]), and tested for differential item functioning by gender with an IRT‐based approach. Among men and women with the same overall posttraumatic stress severity, women tended to report more frequent concentration difficulties and distress from reminders whereas men tended to report more frequent nightmares, emotional numbing, and hypervigilance. These item‐level gender differences were small (on average d = 0.05), however, and had little impact on PCL measurement precision or expected total scores. For practical purposes, men's and women's severity estimates had similar reliability. This provides evidence that men and women veterans demonstrate largely similar profiles of posttraumatic stress symptoms following exposure to military‐related stressors, and some theoretical perspectives suggest this may hold in other traumatized populations.  相似文献   
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88.
In five conscious dogs with chronic gastric fistulas we studied the effect of somatostatin solutions on pentagastrin-stimulated acid secretion. Somatostatin was dissolved in 0.154 M NaCl alone or in the same amount of saline to which dog albumin had been added to give a 0.5% solution. Somatostatin produced a dose-dependent inhibition of pentagastrin-stimulated gastric secretion. However, the inhibition was significantly less when somatostatin was dissolved in saline as compared to saline plus albumin. This study suggests that albumin should be added to somatostatin solutions to preserve biological activity, and it confirms previous reports indicating that, without albumin, basic peptides have a tendency to stick to infusion systems.  相似文献   
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