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51.
INTRODUCTION: Choosing surgery as a career is declining among U.S. medical students. The 8-wk third year surgery clerkship at our institution can be an intense learning experience, and we hypothesized that during this clerkship medical student quality-of-life would drop significantly from baseline, and that this drop would be greater among certain subgroups, such as women students not interested in pursuing a surgical career, and those who place a high value on a controllable lifestyle. METHODS: At clerkship orientation (baseline), students were asked to complete a survey that measured quality-of-life on an 84-point scale, and depression on a 40-point scale. The quality-of-life scale was composed of select questions from the Medical Outcomes Study, and the Harvard Department of Psychiatry/NDSD brief screening instrument was used to measure depression. Students were also asked the typical number of hours they slept per night. Demographics, attitude toward a controllable lifestyle, and top three specialties of interest were also gathered at baseline. On week 6 of the clerkship, students were surveyed on the same quality-of -life and depression scales, and asked average hours of sleep per night for the previous week. RESULTS: From June 2005 through December 2006, 143 of 177 (81%) students agreed to participate, and after exclusions for missing data, 137 students were included in the analysis. Sixty-nine students were women (51%), and the average age was 25.8 (sd 2.6). Mean quality-of-life at baseline was 57.0 (sd 11.3) and at week 6 was 50.4 (sd 10.1) representing a statistically significant average decline of 6.6 points (P < 0.0001). Mean depression at baseline was 14.4 (sd 3.8) and at week 6 was 15.1 (sd 3.6), representing a small but significant average decline of 0.7 points (P = 0.0155). Mean sleep at baseline was 6.3 h/night (sd 0.9) and at week 6 was 5.7 h/night (sd 1.2), representing a statistically significant average decline of 0.6 h/night (P < 0.0001). Declines were similar on all outcomes between men versus women, those who ranked surgery in their top three career choices versus those who did not, and those who ranked controllable lifestyle as "very important" versus all other categories. CONCLUSION: Quality-of-life and sleep declines and depression increases significantly in third-year medical students from orientation to week 6 of their surgery clerkship at our institution. We look forward to studying quality-of-life on other clerkships for comparison, assessing whether the magnitude of this decline in quality-of-life predicts students avoiding a future career in surgery, and testing interventions to prevent this decline in quality-of-life during the clerkship.  相似文献   
52.
PURPOSE: The purpose of this study was to evaluate the treatment of patients with Mason type III radial head fracture with and without elbow dislocation by open reduction with internal fixation, collateral ligament repair, and early mobilization. An additional purpose was to investigate whether there is any effect of elbow dislocation on the severity and functional outcome. METHODS: Twenty-five patients were treated with open reduction with internal fixation using low-profile miniplate and screws for comminuted fracture of the radial head. Eighteen fractures were Mason type III, and 7 fractures were Mason type III with elbow dislocation. There were 5 women and 20 men with a mean age of 34 years. The mean follow-up time was 27 months. Patients were reviewed for functional ability, physical examination, and radiographic assessment. RESULTS: The mean functional index in Mason type III fracture and Mason type III fracture with elbow dislocation was 87 for both groups. The mean range of motion at the elbow joint was calculated as 5 degrees extension to 136 degrees flexion for Mason type III and 7 degrees extension to 133 degrees flexion for Mason type III with elbow dislocation. The mean pronation and supination for all patients were 74 degrees and 67 degrees , respectively. CONCLUSIONS: Selected Mason III radial head fractures and fracture dislocations could be stabilized satisfactorily with internal fixation. Meticulous surgical technique, combined with rigid internal fixation, can allow early motion of the forearm and elbow after fixation of Mason type III radial head fractures with and without elbow dislocation and ligamentous injury. We believe there is still a role for prosthetic replacement in comminuted Mason III radial head fractures that cannot reliably be treated with open reduction and internal fixation. TYPE OF STUDY/LEVEL OF EVIDENCE: Prognostic II.  相似文献   
53.
Stepwise rising CO2 insufflation as an ischemic preconditioning method   总被引:2,自引:0,他引:2  
BACKGROUND: The pneumoperitoneum (Pp) is associated with ischemia and reperfusion (I/R) injury and oxidative stress. Various ischemic-preconditioning (IP) methods were used to reduce ischemic injury in intra-abdominal organs. In this experimental, randomized, controlled trial with a blind assessment of the outcome, we evaluated the effects of a new IP method, stepwise rising CO(2) insufflation, on oxidative stress and inflammatory cytokine response. METHODS: Twenty-one rats were divided into three groups. Rats in the control group were subjected to general anesthesia for only 60 minutes. The stepwise group was subjected to 5 mm Hg for 10 minutes, 10 mm Hg for 10 minutes, and 15 mm Hg of CO(2) insufflation for 60 minutes without deflation. In the Pp15 group, the pressure of CO(2) insufflation was fixed at 15 mm Hg for 60 minutes without deflation. Liver and blood samples were examined to determine malondialdehyde (MDA), the antioxidant, superoxide dismutase (SOD), and inflammatory cytokine (tumor necrosis factor-alpha [TNF-alpha], interleukin-6 [IL-6]) levels. Histopathologic scores of liver tissue were examined in all groups. RESULTS: The highest plasma and liver MDA, TNF-alpha, and IL-6 values were in the Pp15 group, followed by the stepwise and control groups. However, plasma and liver SOD levels determined in the control group were significantly higher, compared to stepwise and Pp15 groups. The lowest plasma and liver levels of SOD were in the Pp15 group, followed by the stepwise and control groups. Significantly higher histopathologic scores were found in the Pp15 group, followed by the stepwise and control groups, as well as MDA and inflammatory cytokine (TNF-alpha, IL-6) levels. CONCLUSIONS: We concluded that the stepwise rising CO(2) insufflation method may be an alternative IP method that may lead to a reduction in I/R injury.  相似文献   
54.
Heterotopic pancreas is a relatively common variant of foregut embryologic dystopia that can be described as pancreatic tissue found outside the normal anatomic location, being independent from vascular supply of normal pancreas. Having all features of pancreatic tissue except for the major duct structures, this ectopic tissue may be clinically recognized when pathologic changes take place. Inflammation, hemorrhagic or obstructive states, and eventually malignancy-related problems may become a diagnostic challenge for clinician and finally lead to consequences of misdiagnosis. In this article we will discuss a case of heterotopic pancreatic tissue located in gastric cardia, which was diagnosed preoperatively as gastrointestinal stromal tumor.Key words: Ectopic pancreas, Pseudocyst, Gastrointestinal stromal tumor, MisdiagnosisHeterotopic (ectopic) pancreas is defined as the presence of pancreatic tissue in an aberrant site that is not anatomically and vascularly connected to the pancreas proper.1,2 Ectopic pancreatic tissue is most commonly found in the duodenum (particularly the second portion), ampulla, stomach (prepyloric antrum), and upper jejunum; it can also occur in the liver, biliary tract, Meckel''s diverticulum, and several other sites such as large bowel, spleen, omentum, mediastinum, lung, thyroid, and even brain.16 The heterotopic pancreatic tissue is usually located in the submucosa and/or the muscularis or subserosa.1,2,4Practically any pancreatic pathology can also occur in the heterotopic pancreatic tissue including acute pancreatitis and neoplastic transformation.1,4,7,8 Episodes of acute pancreatitis may cause local inflammation and typical pancreatitis-related complications in the host organ. The ectopic pancreatic tissue can lead to ulceration and bleeding in the cases located beneath a mucosa. Being a mass-forming lesion, it may also result in luminal obstruction (particularly in the prepyloric antrum).1,4Although it is a relatively common congenital anomaly (0.5% to 13% in autopsy series), in most cases heterotopic pancreas remains clinically silent and is found incidentally during surgery or an endoscopic and/or radiological investigation.1,9 Heterotopic pancreas may be confused with other solid tumors of the host organ.Heterotopic pancreas in the stomach is usually located in the prepyloric area.10 We report here an unusual case of heterotopic pancreas with a pseudocyst formation in the gastric cardia mimicking gastrointestinal stromal tumor.  相似文献   
55.
Background: A variety of lasers have been used for the treatment of rosacea. However, treatment of this condition with long-pulsed neodymium-doped yttrium aluminium garnet laser has not been reported yet. Objective: To assess the efficacy and safety of long-pulsed neodymium-doped yttrium aluminium garnet laser in two different subtypes (erythematotelangiectatic and papulopustular) of rosacea. Methods: A total of 66 patients were enrolled in the study. All of the patients were treated with long-pulsed neodymium-doped yttrium aluminium garnet laser with 3- to 4-week intervals. Rosacea severity score was assessed by using photographs. Improvement in severity was defined as the percentage reduction in severity scores from baseline to the end of treatment. Patients were also asked about their own opinions of improvement at the end of the treatment. Side effects were also documented. Results: Good to excellent improvement was achieved in up to 50 percent of the patients in the erythematotelangiectatic and papulopustular groups. Percent improvement of global severity was significantly greater in the erythematotelangiectatic patients than in the papulopustular patients. The majority of patients from both groups noted a significant improvement of the lesions. Hypopigmented atrophic scars were seen in two patients. Conclusion: The long-pulsed neodymium-doped yttrium aluminium garnet laser is a safe and effective treatment for vascular and inflammatory lesions of rosacea.Rosacea is a chronic inflammatory cutaneous disorder with periods of exacerbations and remissions. Clinical findings are characterized by flushing, erythema, telangiectasia, papules, and pustules. There are four recognized subtypes—erythematotelangiectatic (ETR), papulopustular (PPR), phymatous, and ocular.1 Although angiogenic and sebaceous factors have been implicated in the etiopathology of the disease, it remains unclear. Vascular abnormalities, dermal matrix degeneration, environmental factors, and microorganisms may have a potential role in the development of rosacea.2Rosacea may significantly affect patients’ lives, leading to considerable psychological and social distress over appearance. Therefore, management of this condition is very important. There is no definite cure. Electrosurgery and lasers can be used to decrease vascular lesions.3 Topical and/or oral antibiotics can be used to suppress the inflammatory lesions. Although these methods are moderately successful in controlling symptoms, relapse usually occurs shortly after the cessation of therapy.4,5Many types of lasers and light devices have been increasingly used in the treatment of rosacea. However, the role of long-pulsed neodymium-doped yttrium aluminium garnet (Nd:YAG) laser in this condition has not been well-studied. In this study, the authors assessed the efficacy of long-pulsed Nd:YAG laser in treating patients with two different subtypes (ETR and PPR patients) of rosacea.  相似文献   
56.
BackgroundIn rectal cancer, extramural vascular invasion (EMVI) is the presence of tumour cells in blood vessels outside the muscular layer, which is associated with poor prognosis. Regression of EMVI on MRI following neoadjuvant chemoradiotherapy or its persistence may have prognostic implications.MethodsThis retrospective study included 52 patients with rectal cancer who underwent total mesorectal excision following long-course neoadjuvant chemoradiotherapy (CRT). EMVI assessments were done on previous pelvic MRIs obtained before neoadjuvant CRT and eight weeks after the completion of neoadjuvant chemoradiotherapy in initially EMVI positive cases.ResultsPersistently EMVI positive patients had worse overall survival and disease-free survival compared to initially EMVI negative patients and patients who returned to negative (p < 0.001 for both). Multivariate analysis identified persistent EMVI positivity after neoadjuvant treatment (HR, 102.9; p = 0.003) as significant independent predictor of worse overall survival; and persistent EMVI positivity (HR, 17.0; p = 0.002), mesorectal fascia involvement after neoadjuvant treatment (HR, 8.0; p = 0.017), and poor differentiation (HR, 10.3, p = 0.012) as significant independent predictors of worse disease-free survival.ConclusionPersistent EMVI positivity after neoadjuvant therapy appears to be an independent factor for poor overall survival; and persistent EMVI positivity as well as mesorectal fascia involvement on post neoadjuvant therapy MRI and poor differentiation appears to be important predictors of poor disease-free survival in rectal cancer patients.  相似文献   
57.
IntroductionSemen induces mucosal changes in the female reproductive tract to improve pregnancy outcomes. Since semen‐induced alterations are likely short‐lived and genital inflammation is linked to HIV acquisition in women, we investigated the contribution of recent semen exposure on biomarkers of genital inflammation in women at high HIV risk and the persistence of these associations.MethodsWe assessed stored genital specimens from 152 HIV‐negative KwaZulu‐Natal women who participated in the CAPRISA 008 trial between November 2012 and October 2014. During the two‐year study period, 651 vaginal specimens were collected biannually (mean five samples per woman). Cervicovaginal lavage (CVL) was screened for prostate‐specific antigen (PSA) by ELISA, whereas Y‐chromosome DNA (YcDNA) detection and quantification were conducted by RT‐PCR, representing semen exposure within 48 hours (PSA+YcDNA+) and semen exposure within three to fifteen days (PSA−YcDNA+). Soluble protein concentrations were measured in CVLs by multiplexed ELISA. T‐cell frequencies were assessed in cytobrushes by flow‐cytometry, and vulvovaginal swabs were used to detect common vaginal microbes by PCR. Linear mixed models adjusting for factors associated with genital inflammation and HIV risk were used to assess the impact of semen exposure on biomarkers of inflammation over multiple visits.ResultsHere, 19% (125/651) of CVLs were PSA+YcDNA+, 14% (93/651) were PSA−YcDNA+ and 67% (433/651) were PSA−YcDNA−. Semen exposure was associated with how often women saw their partners, the frequency of vaginal sex in the past month, HSV‐2 antibody detection, current gonorrhoea infection and Nugent Score. Both PSA detection (PSA+YcDNA+) and higher cervicovaginal YcDNA concentrations predicted increases in several cytokines, barrier‐related proteins (MMP‐2, TIMP‐1 and TIMP‐4) and activated CD4+CCR5+HLA‐DR+ T cells (β = 0.050; CI 0.001 to 0.098; p = 0.046) and CD4+HLA‐DR+ T cells (β = 0.177; CI 0.016 to 0.339; p = 0.032) respectively. PSA detection was specifically associated with raised pro‐inflammatory cytokines (including IL‐6, TNF‐α, IP‐10 and RANTES), and with the detection of BVAB2 (OR = 1.755; CI 1.116 to 2.760; p = 0.015), P. bivia (OR = 1.886; CI 1.102 to 3.228; p = 0.021) and Gardnerella vaginalis (OR = 1.815; CI 1.093 to 3.015; p = 0.021).ConclusionsMore recent semen exposure was associated with raised levels of inflammatory biomarkers and the detection of BV‐associated microbes, which declined by three to fifteen days of post‐exposure. Although transient, semen‐induced alterations may have implications for HIV susceptibility in women.  相似文献   
58.
Bleeding from esophageal varices is an important cause of morbidity and mortality in children with portal hypertension. The treatment protocol is planned according to the etiologic factors underlying the portal hypertension, which may be either intrahepatic or extrahepatic. Although portasystemic venous shunt operations were common previously, they are now regarded as nonphysiologic and are rarely used because of their unexpected results and complications. Today, in many centers, endoscopic procedures have become the first-step treatment modality in bleeding esophageal varices. More complicated surgical procedures, such as devascularization procedures in extrahepatic portal hypertension, and liver transplantation in patients with failing liver, should be performed when conservative measures fail. We followed up 69 patients with portal hypertension with endoscopic sclerotherapy in our department. Here we present a retrospective evaluation of the effect of the Sugiura operation on the prognosis of 12 children (6 with extrahepatic and 6 with intrahepatic portal hypertension) who were not responsive to the sclerotherapy program. No rebleeding was seen in 9 of the 12 (75%) patients after the procedure, and the mortality rate in this series was 1 of 12 (8.3%); this patient died of hepatic failure. Received: November 7, 2000 / Accepted: January 25, 2001  相似文献   
59.
Although, one out of every eight women has a risk of developing breast cancer, the reported incidence of breast carcinoma detection in reduction mammaplasty materials is rather low. To our knowledge, specimen radiography, which is used for breast biopsies has not been used for the assessment of breast reduction materials. We investigated the applicability of specimen radiography and its potential benefits in detection of the breast pathologies, especially malignancies in reduction mammaplasty materials. Forty patients scheduled for reduction mammaplasty operation were included. In all cases an inferior pedicle reduction technique was preferred and the radiographs of the resected breast tissues were taken immediately. The radiographs were evaluated for any possible pathologic appearance and all abnormal findings were marked. For the histopathologic evaluation, in addition to the random sampling of the pathologist, any marked areas were also microscopically examined. In two cases fibrocystic changes were found in radiographs and the same results were obtained in the histological examination. No false negative mammogram was seen. Specimen radiography, which is applicable for breast reduction materials is an easy and cheap method and does not cause any patient discomfort. It seems that the radiographs of reduction mammaplasty materials are useful to provide guidance to the pathologist during tissue sampling for microscopic examination especially when large amounts of breast tissue is excised.  相似文献   
60.
OBJECTIVE: N-acetylcysteine (NAC) has yielded some promising results recently in the prevention of radiocontrast nephropathy (RCN). In this study, the structural and functional effects of NAC on RCN were analyzed. MATERIAL AND METHODS: Twenty-eight Wistar rats were randomized into four groups, as follows: Group 1, controls; Group 2, contrast; Group 3, contrast+NAC; and Group 4, NAC. All rats were deprived of water for 24 h and then contrast medium (ioxoglate; 10 ml/kg) was administered to Groups 2 and 3. NAC (50 mg/kg) was introduced enterally to Groups 3 and 4 at a dose of 50 mg/kg in 0.5 ml of distilled water, in four sequential doses 12h apart, starting after 12?h of water deprivation. After 4 days, rats were sacrificed. Creatinine clearance was calculated. The malondialdehyde (MDA) level was quantified in tissue samples. Slides stained with hematoxylin-eosin and periodic acid-Schiff were examined by means of light microscopy. Each tubular cross-section from all images was scored as either mild (preserved brush border, no necrosis), moderate (loss of brush border, no necrosis) or severe (loss of brush border accompanied by necrosis) and the frequencies of these lesion severities were compared. RESULTS: Mean baseline serum creatinine levels and creatinine clearances were similar in all groups. Mean serum creatinine level increased significantly only in Group 2 (0.6+/-0.1 vs 0.7+/-0.2 mg/dl; p<0.05). Tissue MDA levels were similar in all groups. Moderate (13.8%+/-1.5% vs 42%+/-1.4%; p<0.05) and severe (0% vs 40%+/-2.1%; p<0.05) lesions were significantly more frequent in Group 2 compared to Group 1. The frequency of severe lesions in Group 3 was found to be halved compared to that in Group 1 (40%+/-2.1% vs 20.2%+/-0.86%; p<0.05). CONCLUSION: NAC protects the kidneys following exposure to contrast medium as it decreased the severity of tubular lesions in rats.  相似文献   
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