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981.
Michaela Nagl Corinna Jacobi Martin Paul Katja Beesdo-Baum Michael Höfler Roselind Lieb Hans-Ulrich Wittchen 《European child & adolescent psychiatry》2016,25(8):903-918
We aimed to assess the prevalence, incidence, age-of-onset and diagnostic stability of threshold and subthreshold anorexia nervosa (AN) and bulimia nervosa (BN) in the community. Data come from a prospective-longitudinal community study of 3021 subjects aged 14–24 at baseline, who were followed up at three assessment waves over 10 years. Eating disorder (ED) symptomatology was assessed with the DSM-IV/M-CIDI at each wave. Diagnostic stability was defined as the proportion of individuals still affected with at least symptomatic eating disorders (EDs) at follow-ups. Baseline lifetime prevalence for any threshold ED were 2.9 % among females and 0.1 % among males. For any subthreshold ED lifetime prevalence were 2.2 % for females and 0.7 % for males. Symptomatic expressions of EDs (including core symptoms of the respective disorder) were most common with a lifetime prevalence of 11.5 % among females and 1.8 % among males. Symptomatic AN showed the earliest onset with a considerable proportion of cases emerging in childhood. 47 % of initial threshold AN cases and 42 % of initial threshold BN cases showed at least symptomatic expressions of any ED at any follow-up assessment. Stability for subthreshold EDs and symptomatic expressions was 14–36 %. While threshold EDs are rare, ED symptomatology is common particularly in female adolescents and young women. Especially threshold EDs are associated with a substantial risk for stability. A considerable degree of symptom fluctuation is characteristic especially for subthreshold EDs. 相似文献
982.
Probiotics partly reverse increased bacterial translocation after simultaneous liver resection and colonic anastomosis in rats 总被引:11,自引:0,他引:11
Seehofer D Rayes N Schiller R Stockmann M Müller AR Schirmeier A Schaeper F Tullius SG Bengmark S Neuhaus P 《The Journal of surgical research》2004,117(2):262-271
BACKGROUND: Bacterial translocation is one important cause of nosocomial infections following major abdominal surgery. Oral administration of probiotics has been proposed to diminish bacterial translocation. MATERIAL AND METHODS: In total 68 rats were divided into seven groups: five of the groups received standard rat chow and were subjected to either sham-operation, 70% liver resection, colonic anastomosis, or a combination of 30 or 70% liver resection with synchronous colonic anastomosis, respectively. In two additional groups with synchronous operation, a combination of four different lactic acid bacteria and four fibers was administered two times daily pre- and postoperatively. Bacterial concentrations in cecum, mesenteric lymph nodes, liver, and spleen were analyzed and blood cultures were taken 48 h after operation. Furthermore, the following parameters were assessed: histological changes in the intestine, intestinal paracellular permeability (Ussing chamber), bursting pressure of the colonic anastomosis, and mitosis rate of the remnant liver. RESULTS: Bacterial translocation was observed in all rats, except in the sham group. Following liver resection, the highest bacterial concentrations were seen in liver and spleen, following colon anastomosis in the mesenteric lymph nodes. Bacterial translocation was increased in the animals with combined operation, in parallel to the extent of liver resection. In rats with colon anastomosis, bacterial concentration in the cecum was also higher than in the sham group. Application of probiotics significantly decreased bacterial concentration in the lymph nodes. In addition, animals with a high cecal concentration of lactobacilli had less translocation than the others. No histological changes were observed in the intestine. Paracellular permeability for ions, but not for the larger molecule lactulose, was increased in the colon in all groups with colon anastomosis. The bursting pressure of the colon anastomosis was not significantly different between the groups. Seventy percent liver resection led to a high rate of hepatocyte mitosis, whereas combination with colon anastomosis impaired the regeneration process. CONCLUSION: Synchronous liver resection and colon anastomosis led to increased bacterial translocation compared to the single operations in the rat model. It is possible to diminish this process by oral administration of probiotics. Bacterial overgrowth in the cecum and impaired hepatic regeneration, but not histological changes or alterations of paracellular permeability, are potential pathogenic mechanisms for translocation in this setting. 相似文献
983.
African American men with localized prostate cancer are less likely than White men to receive a radical prostatectomy. This disparity may exist because African American men have prostate cancers that are more biologically aggressive. We investigated if similar stage cancers of African American men and White men show differences in cancer control after radical prostatectomy. Men with localized prostate cancer who underwent radical prostatectomy during a 6-yr period were stratified by race, and time to prostate-specific antigen recurrence was measured. We used Chi-square and t-tests to compare baseline clinical and pathological factors based on race. Cox proportional hazards model was used to determine effects of race on cancer control while controlling for baseline measures of cancer severity. There were 1,228 cases evaluated. At baseline, African American men were treated at a significantly younger age than White men (P = 0.0027) but showed no significant difference in prostate-specific antigen PSA, Gleason score, pathology stage, maximum tumor dimension, and surgical margin status. Multivariable Cox proportional hazards analysis controlling for cancer severity at prostatectomy revealed that cancer-free survival was not worse among African Americans compared to other subjects (P = 0.16). The responsiveness of prostate cancers among African American men to radical prostatectomy was similar to White men of similar stage and grade. Early detection in African American men may facilitate diagnosis of cancer amenable to prostatectomy. Studies are needed to evaluate the possible interaction of prostate cancer stage and grade shift in African American men and the disease free survival in this population. 相似文献
984.
Chronic rejection: insights from a novel immunosuppressive-free model of kidney transplantation 总被引:2,自引:0,他引:2
Gasser M Waaga-Gasser AM Kist-van Holthe JE Yuan X Lenhard SM Abdallah KA Chandraker A 《Journal of the American Society of Nephrology : JASN》2004,15(3):687-694
The use of immunosuppressive drugs in models of chronic rejection may limit their usefulness for mechanistic studies. We have developed a new minor histocompatibility-mismatched rat kidney transplant model without the need for immunosuppression. Kidneys from LEW (RT1(l)) donors were transplanted to congenic WF.1L (RT1(l)) recipients and compared with the reversed strain combination and isogenic controls. Urinary protein excretion was measured serially in all recipients; kidneys were harvested 90, 120, and 180 d after transplantation for morphologic analysis and cytokine gene expression. In vitro lymphocytic reactivity and cytokine analysis of mixed lymphocyte reaction (MLR) culture supernatants by ELISA was also carried out. LEW into WF.1L kidney grafts developed proteinuria starting 120 d after transplantation and were associated with morphologic changes of focal segmental glomerulosclerosis together with interstitial cell infiltrates, upregulated gene expression of IL-1beta, IL-2, and TNF-alpha/-beta, as well as IL-2, IFN-gamma, and TNF-alpha production by lymphocytes in MLR culture supernatants. WF.1L kidneys transplanted into LEW recipients did not develop chronic rejection and had upregulation of Th2 cytokines, both within the allograft and in MLR supernatant of recipient lymphocytes cultured with WF.1L cells. Furthermore, these lymphocytes produced both Th1 and Th2 cytokines when cultured with WF cells, unlike lymphocytes from the LEW isografts, which produced Th1 cytokines when challenged with WF cells. These studies show that indirect allorecognition can cause strain-dependent chronic rejection associated with Th1-like cytokine production, whereas production of Th2 cytokines is associated with protection from the development of chronic rejection. 相似文献
985.
A mixed-flow blood pump for long-term applications has been developed at the Helmholtz-Institute in Aachen, Germany. Central features of this implantable pump are a centrally integrated motor, a blood-immersed mechanical bearing, magnetic coupling of the impeller, and a shrouded impeller, which allows a relatively wide clearance. The aim of the study was a numerical analysis of hydraulic and hemolytic properties of different impeller design configurations. In vitro testing and numerical simulation techniques (computational fluid dynamics [CFD]) were applied to achieve a comprehensive overview. Pressure-flow charts were experimentally measured in a mock loop in order to validate the CFD data. In vitro hemolysis tests were performed at the main operating point of each impeller design. General flow patterns, pressure-flow charts, secondary flow rates, torque, and axial forces on the impeller were calculated by means of CFD. Furthermore, based on streak line techniques, shear stress (stress loading), exposure times, and volume percentage with critical stress loading have been determined. Comparison of CFD data with pressure head measurements showed excel-lent agreement. Also, impressive trend conformity was observed between in-vitro hemolysis results and numerical data. Comparison of design variations yielded clear trends and results. Design C revealed the best hydraulic and hemolytic properties and was chosen as the final design for the mixed-flow rotary blood pump. 相似文献
986.
Reduced variability of acetabular cup positioning with use of an imageless navigation system 总被引:10,自引:0,他引:10
Nogler M Kessler O Prassl A Donnelly B Streicher R Sledge JB Krismer M 《Clinical orthopaedics and related research》2004,(426):159-163
Positioning the acetabular component is one of the most important steps in total hip arthroplasty; malpositioned components can result in dislocations, impingement, limited range of motion, and increased polyethylene wear. Conventional surgery makes use of specialized alignment guides provided by the manufacturers of the implants. The use of mechanical guides has been shown to result in large variations of cup inclination and version. We investigated acetabular cup alignment with the nonimage-based hip navigation system compared with a conventional mechanically guided procedure in 12 human cadavers. Postoperative cup position relative to the pelvic reference plane was assessed in both groups with the use of a three-dimensional digitizing arm. In the navigated group, a median inclination of 45.5 degrees and a median anteversion of 21.9 degrees (goals, 45 degrees and 20 degrees) were reached. In the control group, the median inclination was 41.8 degrees and the median anteversion was 24.6 degrees. The ninetieth percentile showed a much wider range for the control group (36.1 degrees-51.8 degrees inclination, 15 degrees-33.5 degrees anteversion) than for the navigated group (43.9 degrees-48.2 degrees inclination, 18.3 degrees-25.4 degrees anteversion). This cadaver study shows that computer-assisted cup positioning using a nonimage-based hip navigation system allowed for more consistent placement of the acetabular component. 相似文献
987.
Stöckl B Nogler M Rosiek R Fischer M Krismer M Kessler O 《Clinical orthopaedics and related research》2004,(426):180-186
Successful total knee arthroplasty is dependent on the correct alignment of implanted prostheses. Major clinical problems can be related to poor femoral component positioning, including sagittal plane and rotational malalignment. A prospective randomized study was designed to test whether an optical navigation system for total knee arthroplasty achieved greater implantation precision than a nonnavigated technique. The primary variable was rotation of the femoral component in the transverse plane, measured from postoperative radiographs and computed tomography images. Sixty-four patients were included in the study. All patients received the Duracon total knee prosthesis. The patients were randomly divided into two groups: Group C patients had conventional total knee arthroplasty without navigation; Group N patients had total knee arthroplasty using a computer-assisted knee navigation system. Analysis showed that patients in Group N had significantly better rotational alignment and flexion angle of the femoral component than patients in Group C. In addition, superior postoperative alignment of the mechanical axis, posterior tibial slope, and rotational alignment was achieved for patients in Group N. The use of a navigation system provides improved alignment accuracy, and can help to avoid femoral malrotation and errors in axial alignment. 相似文献
988.
Short- and long-term results of liver transplantation in infants aged less than 6 months 总被引:6,自引:0,他引:6
Grabhorn E Schulz A Helmke K Hinrichs B Rogiers X Broering DC Burdelski M Ganschow R 《Transplantation》2004,78(2):235-241
BACKGROUND: Despite major surgical and medical advances, it is still a challenge to perform transplantation in small infants. This study, focusing on short- and long-term outcomes, summarizes our 10-year experience with liver transplantation (LTx) in infants aged less than 6 months. PATIENTS AND METHODS: We analyzed 43 patients aged 6 months or less (range: 12-184 days, median: 136 days) whose median weight at the time of LTx was 5.8 kg (range: 2.8-8.0 kg). The reasons for LTx were biliary atresia (n=27; 62.8%), neonatal hepatitis (n=6; 14%), neonatal cholestasis (n=4; 9.3%), and miscellaneous (n=6; 14%). The patients were followed up for a median time of 3 years and evaluated with respect to graft function, physical, and neurodevelopmental outcome. RESULTS: The patient survival was 90.7% after 1 year and 87.2% after 2 years. The graft survival was 86% after 1 year and 82.1% after 2 years. Twelve patients (27.9%) experienced 15 surgical complications requiring intervention, two of whom demonstrated vascular thrombosis (4.7%). Acute early rejection occurred in 15 patients (34.9%), and chronic rejection occurred in 3 patients (7%); 83.3% of the patients had normal liver function test results at the time of evaluation. Complications such as posttransplant lymphoproliferative disease (4.7%) and persistent arterial hypertension (4.7%) were rarely seen. The physical and neurodevelopmental outcomes were good. CONCLUSIONS: LTx in infants aged less than 6 months provides excellent short- and long-term results. Low weight or young age of infants awaiting LTx should not be exclusion criteria for LTx. 相似文献
989.
BACKGROUND: Surgical resection remains the treatment of choice for patients with colorectal cancer metastatic to the liver. Hepatic arterial infusion pump (HAIP) chemotherapy in combination with surgical resection has been demonstrated in a recent study to improve disease-free and overall survival for patients with colorectal cancer metastatic to the liver. Other reports, however, have indicated significant toxicity related to HAIP chemotherapy in the form of biliary sclerosis. Thus, the value of adjuvant HAIP chemotherapy following hepatic resection or ablation remains controversial. The aim of this study was to examine the survival and toxicity in a single institutional experience with adjuvant HAIP chemotherapy. METHODS: Review of a prospective hepatobiliary database was performed. HAIP were placed in the standard technique following resection and/or radiofrequency ablation (RFA) of all liver metastases. Patients received floxuridine (FUDR) via the HAIP at standard doses. Complications were graded according to a standard 5-point grading scale. Statistical analysis was performed by chi(2) test. RESULTS: Thirty-four of 86 patients underwent placement of HAIP at the time of hepatic resection or ablation between January 1999 and November 2002. The HAIP group demonstrated a significantly greater (P <0.05) number (median 5 vs. 2) and size (median 5 cm vs. 3 cm) of hepatic lesions compared to the group without HAIP. The HAIP group experienced a greater frequency of complications (53% vs. 33%), with 6 (18%) patients in the HAIP group demonstrating biliary sclerosis. There were no deaths within 30 days of surgery. Median survival was similar in both groups (HAIP 20 months, no HAIP 24 months). CONCLUSIONS: Patients in the HAIP group had significantly worse overall predictors of outcome in metastatic colorectal cancer, yet the median overall survival in both groups was similar. However, adjuvant HAIP chemotherapy was associated with significantly greater morbidity. Given the availability of newer active systemic agents and regimens, the value of adjuvant HAIP chemotherapy remains controversial. 相似文献
990.
The prevention of incisional hernia formation using a delayed-release polymer of basic fibroblast growth factor 总被引:7,自引:0,他引:7 下载免费PDF全文
OBJECTIVE: We sought to reduce the high incidence of abdominal wall incisional hernias using sustained release growth factor therapy. SUMMARY BACKGROUND DATA: Incisional hernias complicate 11% of abdominal wall closures, resulting in 200,000 incisional hernia repairs in the United States each year. Mechanical improvements alone in mesh, suture material, and surgical technique have failed to reduce the high rate of fascial wound failure. METHODS: Sprague-Dawley rats underwent midline celiotomies that were closed with fast-absorbing suture to induce early biomechanical wound failure and incisional hernia formation. In primary wounds, fascial incisions were closed adjacent to a continuous release polygalactone polymer rod containing basic fibroblast growth factor (bFGF), no growth factor (control-rod), or without rods. In a second group, incisional hernias were repaired with either bFGF or control-rod therapy. Breaking strength was measured on postoperative day (POD) 7, and the incidence of incisional hernia formation was determined on POD 28. RESULTS: Treatment with bFGF rods significantly increased fascial wound breaking strength. In the "hernia-prevention" experiments, incisional hernias developed in 90% of untreated incisions, 60% of control-rod incisions, and only 30% of bFGF-rod incisions (P < 0.05). In the "hernia-treatment" experiments, recurrent incisional hernias developed in 86% of control-rod incisions compared with only 23% of bFGF-rod treated incisions (P < 0.05). Immunohistochemistry demonstrated increased angiogenesis and collagen protein production in bFGF treated incisions. CONCLUSION: The treatment of abdominal fascial incisions with a sustained-release bFGF polymer significantly lowered the incidence of incisional hernias and the recurrence rate after repair. 相似文献