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981.
The purpose of this research was to determine if the conventional keratometer measures tangential or sagittal radius. A Bausch and Lomb keratometer was modified to enable an assessment of vertex radius and p-value to be made on convex conicoidal buttons of known surface form. Calculation of these two parameters was achieved assuming that the keratometer was measuring tangential radius and then repeated assuming a sagittal measurement. The resulting values could then be compared with those obtained by Form Talysurf analysis and by the use of an autokeratometer designed to measure sagittal radius. There was good agreement between the three instruments when the modified Bausch and Lomb keratometer was assumed to measure sagittal radius. We conclude that the Bausch and Lomb keratometer makes a radius measurement closer to the sagittal than the tangential radius of a conicoid of revolution.  相似文献   
982.
Introduction: Social media developments have completely changed how information is accessed and communicated. While great potential exists with these platforms, recent reports of online unprofessional behavior by doctors has threatened the medical professional identity; a matter of critical importance for clinicians and medical educators. This paper outlines a role for social media in facilitating support for clinicians and medical teachers; it will raise awareness of pitfalls and explain ethical and legal guidelines.

Methods: An analysis of inappropriate behaviors and conflicting attitudes regarding what is acceptable in online posts, including the inter-generational contrast in online presence and perceptions of where the boundaries lie.

Results and discussion: Guidance documents are analyzed and potentially confusing and conflicting statements are identified and clarified. The authors believe that clinicians and medical students must follow ethical imperatives in both personal and professional spheres.

Conclusions: It is essential that medical educational and professional bodies encourage clinicians to support one another and share information online while providing clear legal and ethical advice on maintaining standards and avoiding common pitfalls. Education on the responsible use of social media and associated risk awareness should be a priority for medical school curricula.  相似文献   

983.
Alterations in regional subcortical brain volumes have been investigated as part of the efforts of an international consortium, ENIGMA, to identify reliable neural correlates of major depressive disorder (MDD). Given that subcortical structures are comprised of distinct subfields, we sought to build significantly from prior work by precisely mapping localized MDD-related differences in subcortical regions using shape analysis. In this meta-analysis of subcortical shape from the ENIGMA-MDD working group, we compared 1,781 patients with MDD and 2,953 healthy controls (CTL) on individual measures of shape metrics (thickness and surface area) on the surface of seven bilateral subcortical structures: nucleus accumbens, amygdala, caudate, hippocampus, pallidum, putamen, and thalamus. Harmonized data processing and statistical analyses were conducted locally at each site, and findings were aggregated by meta-analysis. Relative to CTL, patients with adolescent-onset MDD (≤ 21 years) had lower thickness and surface area of the subiculum, cornu ammonis (CA) 1 of the hippocampus and basolateral amygdala (Cohen's d = ?0.164 to ?0.180). Relative to first-episode MDD, recurrent MDD patients had lower thickness and surface area in the CA1 of the hippocampus and the basolateral amygdala (Cohen's d = ?0.173 to ?0.184). Our results suggest that previously reported MDD-associated volumetric differences may be localized to specific subfields of these structures that have been shown to be sensitive to the effects of stress, with important implications for mapping treatments to patients based on specific neural targets and key clinical features.  相似文献   
984.
Cytomegalovirus (CMV) pneumonitis is one of the most severe manifestations of CMV disease among immunocompromised patients. The diagnosis of CMV pneumonitis traditionally has required the use of invasive procedures such as lung biopsy. In this retrospective study, we evaluated a centrifugation culture method in samples of bronchoalveolar fluid for the noninvasive diagnosis of CMV pneumonitis. During a 9-mo period, 75 bronchoalveolar lavage samples were collected from 58 patients with pneumonitis. We analyzed the data from 21 patients in whom lung tissue samples were obtained within 14 days of the bronchoalveolar lavage. Centrifugation cultures of bronchoalveolar fluid were positive for CMV in 12 cases. CMV pneumonitis was confirmed in samples of lung tissue from five (42%) of the 12 patients, whereas no evidence of CMV pneumonitis was found in the remaining seven (58%) cases. Of nine patients with negative centrifugation cultures, CMV pneumonitis was confirmed in two (22%). When compared with conventional cultures, we found bronchoalveolar lavage fluid centrifugation cultures to be highly sensitive (100%) and specific (92%) for the detection of CMV infection. However, detection of CMV by centrifugation culture proved to be only moderately sensitive (71%) and nonspecific (50%) for the diagnosis of CMV pneumonitis.  相似文献   
985.
Background: Enhanced recovery after surgery (ERAS) or fast-track surgery is a perioperative and postoperative care concept initiated in the early 1990s aiming to reduce the length of hospital stays following elective abdominal surgery. Twenty treatment items defined in the Consensus Guidelines established in 2009 were included in this concept. The success of ERAS depends highly on multidisciplinary teamwork and patient compliance. Several ERAS items and their impact on perioperative and postoperative care have recently been discussed. In this connection, translational research topics triggered increasing interest in ERAS and new impulses aimed at improving the ERAS concept. We thus reviewed the surgical literature to highlight the role of translational research items in ERAS. Methods: A literature search of Medline?, PubMed? and the Cochrane Database was performed. Two investigators independently reviewed the abstracts and appropriate articles were included in this review. Results: Articles have been selected. The advantages of the ERAS concept over conventional postoperative care were established by four meta-analyses and several reviews. But, due to the lack of standardization of the protocols, the level of evidence is still low. The implementation of ERAS into clinical practice is furthermore hampered by the poor compliance with ERAS protocols and remains a challenge for the future. Moreover, recent trials challenge the role of some ERAS items, e.g. epidural anesthesia. Translational research trials investigating stress, immune and inflammatory response after surgery, new analgesic concepts, goal-directed fluid therapy and new drugs and substances to improve the outcome of ERAS provide first promising data but still need to be integrated in the ERAS concept. Conclusion: The Consensus Guidelines for ERAS are subject to the constant evolution of treatment strategies and implementation of translational research findings. Improvement of the compliance with ERAS protocols in surgical clinics and updating of ERAS items taking into account recent findings in translational research may improve the outcomes of ERAS but remain a long-term challenge in surgery for the next years.  相似文献   
986.

Objective

Percutaneous mechanical thrombectomy (PMT) is regularly used in the treatment of both venous and arterial thrombosis. Although there has been no formal report, PMT has been linked to cases of reversible postoperative acute kidney injury (AKI). The purpose of this study is to evaluate the risk of renal dysfunction in patients undergoing PMT vs catheter-directed thrombolysis (CDT) for treatment of an acute thrombus.

Methods

This study is a retrospective review of all patients in a single institution with a Current Procedural Terminology code for PMT or CDT from January 2009 through December 2014. Each patient was grouped into one of the four following procedural categories: PMT only, PMT with tissue plasminogen activator (tPA) pulse-spray, PMT with CDT, or CDT only. Preoperative and postoperative creatinine and glomerular filtration rate (GFR) values were obtained for each patient. The RIFLE (Risk, Injury, Failure, Loss, and End-stage renal disease) criteria were used to categorize the extent of renal dysfunction. χ2 analysis, one-way analysis of variance, and unpaired t-test were used to assess significance.

Results

A total of 227 patients were reviewed, of which 82 were excluded due to either existence of preoperative AKI, history of end-stage renal disease, or lack of clinical data. Of the remaining 145 patients, 53 (37%) presented with arterial thrombosis (mean age, 62 years; 43% male) and 92 (63%) presented with venous thrombosis (mean age, 48 years; 45% male). The incidence of renal dysfunction was highest in the PMT/tPA pulse group (21%), followed by the PMT group (20%) and the PMT/CDT group (14%). CDT was not associated with renal dysfunction. PMT (P = .046), and PMT/tPA pulse (P = .033) were associated with higher rates of renal dysfunction than the CDT controls. The average preoperative GFR for the 22 patients who developed AKI was 53.7 ± 9.4 mL/min/1.73 m2. The minimum postoperative GFR within 48 hours was an average of 35 ± 16 mL/min/1.73 m2. Stratified by the RIFLE criteria, 13 (9%) patients progressed to the risk category, 6 (4%) progressed to the injury category, and 3 (2%) progressed to the failure category. None of the patients who developed renal dysfunction from PMT progressed to dialysis within the same admission period.

Conclusions

The use of PMT as a treatment for vascular thrombosis is associated with renal dysfunction. Patients treated with PMT require postoperative vigilance and renal protective measures.  相似文献   
987.
Objective  The aim of this study was to compare the outcomes of enucleation versus resection in patients with small pancreatic, ampullary, and duodenal neuroendocrine tumors (NETs). Methods  Multi-institutional retrospective review identified all patients with pancreatic and peri-pancreatic NETs who underwent surgery from January 1990 to October 2008. Patients with tumors ≤3 cm and without nodal or metastatic disease were included. Results  Of the 271 patients identified, 122 (45%) met the inclusion criteria and had either an enucleation (n = 37) and/or a resection (n = 87). Enucleated tumors were more likely to be in the pancreatic head (P = 0.003) or functioning (P < 0.0001) and, when applicable, less likely to result in splenectomy (P = 0.0003). The rate of pancreatic fistula formation was higher after enucleation (P < 0.01), but the fistula severity tended to be worse following resection (P = 0.07). The enucleation and resection patients had similar operative times, blood loss, overall morbidity, mortality, hospital stay, and 5-year survival. However, for pancreatic head tumors, enucleation resulted in decreased blood loss, operative time, and length of stay compared to pancreaticoduodenectomy (P < 0.05). Conclusion  These data suggest that most outcomes of enucleation and resection for small pancreatic and peri-pancreatic NETs are comparable. However, enucleation has better outcomes than pancreaticoduodenectomy for head lesions and the advantage of preserving splenic function for tail lesions. Presented at the 2009 American Hepatopancreaticobiliary Association, March 14, 2009, Miami, FL American College of Surgeons Resident Research Scholarship, NIH Grant T32 CA009614 Physician Scientist Training in Cancer Medicine.  相似文献   
988.
Breast‐specific gamma imaging (BSGI) is a physiologic breast imaging modality that provides more sensitive detection of breast lesions than mammography or ultrasound, and appears to have greater specificity than breast MRI. The purpose of this study was to evaluate how often BSGI changed surgical management in patients with breast cancer. Charts were reviewed from 218 consecutive eligible patients who had preoperative evaluation with BSGI or MRI before surgery for breast cancer from January 2008 to May 2010. Patients who were initially considered eligible for breast‐conserving therapy (BCT) were evaluated to determine how many ultimately had mastectomies. Patients who underwent mastectomy because of personal choice or ineligibility for BCT were excluded. Management was changed to mastectomy in 11.9% of those who had BSGI and 28.9% of those who had MRI. Review of pathology demonstrated that all patients who underwent mastectomies were not candidates for breast conservation. 15.4% of patients who underwent BCT based on BSGI findings required a single re‐excision due to positive surgical margins. 14.4% required mastectomy. In the MRI group, 18.8% required a single re‐excision, and 6.3% required mastectomy. Evaluation with BSGI changed management to mastectomy in a substantial proportion of patients believed to be eligible for BCT following standard imaging. BSGI is effective in evaluation of extent of disease in patients with breast cancer, and is comparable to MRI in terms of its influence on surgical management.  相似文献   
989.
Background Revascularization of a limb following prolonged ischemia results in substantial skeletal muscle injury. Statins play a well-understood role in the treatment of hypercholesterolemia but are also known to have anti-inflammatory properties. The purpose of this study was to examine the effects of pravastatin pre-treatment in the setting of skeletal muscle ischemia reperfusion injury (IRI).

Methods Adult male Sprague Dawley rats (n = 27) were randomized into 3 groups: control group, I/R group, IR group pre-treated with pravastatin. Bilateral hind-limb ischemia was induced by rubber band application proximal to the level of the greater trochanters for 2.5 h. Treatment groups received normal saline in equal volumes prior to tourniquet release. Following 12 h reperfusion, the tibialis anterior muscle was dissected and muscle function assessed electrophysiologically by electrical field stimulation. The animals were then killed and skeletal muscle harvested for evaluation.

Results We found that pre-treatment with pravastatin reduces the tissue oxidative damage and edema associated with skeletal muscle reperfusion injury. Skeletal muscle injury, measured by edema, leucose-questration and electrical properties were significantly lower with pravastatin pre-treatment compared to the non-treated group.

Interpretation We feel that pravastatin pre-treatment may be a potential therapeutic intervention for skeletal muscle ischemia reperfusion injury in the clinical setting. ▪  相似文献   
990.
Diagnostic and therapeutic strategies for acute biliary inflammation/infection (acute cholangitis and acute cholecystitis), according to severity grade, have not yet been established in the world. Therefore we formulated flowcharts for the management of acute biliary inflammation/infection in accordance with severity grade. For mild (grade I) acute cholangitis, medical treatment may be sufficient/appropriate. For moderate (grade II) acute cholangitis, early biliary drainage should be performed. For severe (grade III) acute cholangitis, appropriate organ support such as ventilatory/circulatory management is required. After hemodynamic stabilization is achieved, urgent endoscopic or percutaneous transhepatic biliary drainage should be performed. For patients with acute cholangitis of any grade of severity, treatment for the underlying etiology, including endoscopic, percutaneous, or surgical treatment should be performed after the patient's general condition has improved. For patients with mild (grade I) cholecystitis, early laparoscopic cholecystectomy is the preferred treatment. For patients with moderate (grade II) acute cholecystitis, early laparoscopic or open cholecystectomy is preferred. In patients with extensive local inflammation, elective cholecystectomy is recommended after initial management with percutaneous gallbladder drainage and/or cholecystostomy. For the patient with severe (grade III) acute cholecystitis, multiorgan support is a critical part of management. Biliary peritonitis due to perforation of the gallbladder is an indication for urgent cholecystectomy and/or drainage. Delayed elective cholecystectomy may be performed after initial treatment with gallbladder drainage and improvement of the patient's general medical condition.  相似文献   
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