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51.
IntroductionLiver transplantation is the standard treatment for end-stage liver disease. Brazil holds the third highest number of liver transplants performed per year, but center maldistribution results in high discrepancies in accessing this treatment. In 2012, an interstate partnership successfully implemented a new liver transplantation program in the middle west of Brazil. Here, we report the results of the first 500 liver transplants performed in this new program and discuss the impacts of a new transplant center in regional transplantation dynamics.MethodsWe reviewed data from the first 500 consecutive deceased donor liver transplants performed in the new program during an 8-year period. We analyzed data on patients’ clinical and demographic profiles, postoperative outcomes, and graft and recipient survival rates. Univariate survival analysis was conducted using log-rank tests to compare the groups.ResultsAlmost half (48%) of the procured organs and 40% of the recipients transplanted in our center were from outside our state. Recipient 30-day mortality was 9%. Overall recipient survival at 1 year and 5 years was 85% and 80%, respectively. Mortality was significantly associated with higher Model for End-Stage Liver Disease (P < .001) but not with the presence of hepatocellular carcinoma (P = .795).DiscussionThe new transplantation program treated patients from different regions of Brazil and became the reference center in liver transplantation for the middle west region. Despite the recent implementation, our outcomes are comparable to experienced centers around the world. This model can inspire the creation of new transplantation programs aiming to democratize access to liver transplantation nationwide.  相似文献   
52.
BackgroundVascular injury after hallux valgus surgery is a rare condition but serious complications can ensue.MethodsWe performed an anatomical study using 26 cadaveric lower extremities. We enhanced first metatarsal bone’s (FMB) vascularization by injecting latex. Each specimen was classified according to the severity of hallux valgus deformity (HVD). Then we measured two distances: one between the first tarsometatarsal joint (FTMJ) to the first dorsal branch’s origin, the other between the first metatarsophalangeal joint (MTP) to the dorsal plexus’s origin.ResultsThe distance between the FTMJ and the first dorsal branch to the FMB ranges from 10 mm in normal feet to 15 mm in severe deformed feet. The distance between the MTP and the dorsal plexus’ origin ranges from 20 mm in normal feet to 25 mm in severe deformed feet.ConclusionsUnderstanding the foot’s vascular anatomy has allowed us to adapt surgical landmarks to the severity of the HVD and to avoid post-operative complications.  相似文献   
53.
54.
Six stroke patients were studied using a dichotic listening CV task, 4 with left hemisphere infarction, 2 with right hemisphere infarction. It was observed a "lesion-effect", a shift of hemisphere prevalence to the side opposite a brain lesion. The authors suggest that the lesion-effect can be explained by the auditory extinction phenomenon at the linguistic level.  相似文献   
55.
Low flow veno-venous ECMO: an experimental study   总被引:1,自引:0,他引:1  
Clinical use of extracorporeal membrane oxygenation (ECMO) and carbon dioxide removal (ECCO 2R) have become well established techniques for the treatment of severe respiratory failure; however they require full cardiopulmonary bypass, representing major procedures with high morbidity. We theorized the possibility of an efficient low flow veno-venous extracorporeal membrane gas exchange method. Four mongrel 12 kg dogs were submitted to veno-venous extracorporeal membrane gas exchange via a jugular dialysis catheter using a low flow (10 ml/min) roller pump and a membrane oxygenator for a period of four hours. Respiratory rate was set at 4 breaths/min with a FiO 2 of 21% and ventilatory dead space was increased. Adequate gas exchange was obtained (pO 2139, pCO 224, Sat 99.4%), without major hemodynamic changes or hematuria. Our results demonstrate the feasibility of a low flow, less aggressive system. Further research should be considered.  相似文献   
56.
The author studied the value of therapeutic test for the diagnosis and treatment of kala-azar in children by comparing two groups of patients. The identification of Leishmania donovani in smears of bone marrow confirmed the diagnosis in all fifty seven patients of the control group. In another group with sixteen children, the diagnosis was based on the successful response to the treatment with meglumine antimonate. In none of the patients of the second group the protozoa was identified and the decision to give the specific treatment was based on epidemiological, clinical, biochemical and hematological criteria for the disease. Statistical analysis was performed by Student t test to compare clinical, biochemical and hematological variables between the groups. None of the differences between the groups was statistically significant, suggesting that the therapeutic test was valid, and all patients who received treatment had kala-azar.  相似文献   
57.
The present study aims to ascertain whether sex selection maybe inadvertently performed in human in-vitro fertilization (IVF)and embryo transfer (IVF-embryo transfer) programmes when selectingfor high quality embryos (those with the fastest cleaving ratesand/or the best morphology) at the fresh transfer cycle. Allpatients entering into the study were treated with gonadotrophinsafter pituitary suppression with gonadotrophin-releasing hormoneagonists (GnRHa) and had intrauterine embryo transfer on day2 post-insemination. These patients were retrospectively dividedinto three groups according to whether the difference in meannumber of cells between embryos transferred and all embryosavailable for transfer in a given cycle was less than (negativeselection), equal to (no selection) or greater (positive selection)than zero. In cycles resulting in singleton births, the sexratio of the resulting babies was significantly (P 0.005) shiftedtoward the female (88.8%) and to the male (90.0%) in the negativeand positive selection groups respectively. No shift in sexratio was observed in cycles resulting in multiple births. Maternalage was another independent factor affecting sex ratio at birth.Sex ratio was significantly (P 0.05) skewed in favour of males(62.7%) and females (71.4%) in women <35 and 235 years ofage respectively. Maternal age, number of embryos transferredand the event of selecting or not selecting the slowest cleavingembryos for transfer were entered automatically in a three-groupdiscriminant model for distinguishing cycles resulting in onlyboys, both boys and girls, and only girls. These data suggestthat (i) sex selection may be inadvertently performed in IVF-embryotransfer programmes when selecting for high quality embryosat the fresh transfer cycles; (ii) human endometria may be favourable,indifferent or hostile to either fast cleaving or slow cleavingembryos depending on maternal age; and (iii) ‘natural’sex selection may be performed for social, psychological ormedical reasons.  相似文献   
58.
There are 80 medical schools in Brazil, of which 14 were selected for this study based on their regional distribution and representative characteristics. A survey in 1995 showed a heavy concentration (86%) of in-house practical training in major university hospitals. Only 14% of the hands-on training of students occurred in primary health or community-based clinics or other services related to the nationwide Unified Health System (SUS). University hospitals have been organized according to the specialized ward model, with extensive fragmentation of health care. This article makes several proposals for improving medical training. Changes in medical care are considered crucial to improvement of physician training. Reforms in medical care in such hospitals would be more important than reformulating the medical school itself. A move towards other health care services is recommended; more time devoted to teaching in primary health care systems and other extramural services is crucial for achieving better physician responsibility and competence.  相似文献   
59.
Laparoscopic management of benign solid and cystic lesions of the liver   总被引:20,自引:0,他引:20  
OBJECTIVE: The authors present their experience in the laparoscopic management of benign liver disease. The aim of the study is to analyze technical feasibility and evaluate immediate and long-term outcome. SUMMARY BACKGROUND DATA: Indications for the laparoscopic management of varied abdominal conditions have evolved. Although the minimally invasive treatment of liver cysts has been reported, the laparoscopic approach to other liver lesions remains undefined. METHODS: Between September 1990 and October 1997, 43 patients underwent laparoscopic liver surgery. There were two groups of benign lesions: cysts (n = 31) and solid tumors (n = 12). Indications were solitary giant liver cysts (n = 16), polycystic liver disease (n = 9), hydatid cyst (n = 6), focal nodular hyperplasia (n = 3), and adenoma (n = 9). Only solid tumors, hydatid cysts, and patients with polycystic disease and large dominant cysts located in anterior liver segments were included. All giant solitary liver cysts were considered for laparoscopy. Patients with cholangitis, cirrhosis, and significant cardiac disease were excluded. Data were collected prospectively. RESULTS: The procedures were completed laparoscopically in 40 patients. Median size was 4 cm for solid nodules and 14 cm for solitary liver cysts. Conversion occurred in three patients (7%), for bleeding (n = 2) and impingement of a solid tumor on the inferior vena cava (n = 1). The median operative time was 179 minutes. All solitary liver cysts were fenestrated in less than 1 hour. There were no deaths. Complications occurred in 6 cases (14.1%). Two hemorrhagic and two infectious complications were noted after management of hydatid cysts. There were no complications after resection of solid tumors. Three patients received transfusions (7%). The median length of stay was 4.7 days. Median follow-up was 30 months. There was no recurrence of solitary liver or hydatid cysts. One patient with polycystic disease had symptomatic recurrent cysts at 6 months requiring laparotomy. CONCLUSION: Laparoscopic liver surgery can be accomplished safely in selected patients with small benign solid tumors located in the anterior liver segments and giant solitary cysts. The laparoscopic management of polycystic liver disease should be reserved for patients with a limited number of large, anteriorly located cysts. Hydatid disease is best treated through an open approach.  相似文献   
60.
OBJECTIVE: The purpose of this study was to assess whether the extent of intestinal metaplasia is related to the severity of the gastroesophageal reflux disease. METHODS: A total of 556 consecutive patients with symptoms suggestive of foregut disease had upper gastrointestinal endoscopy with extensive biopsies from the gastroesophageal junction and the esophagus. All patients had esophageal motility and 24-hour pH monitoring. In 411 patients, cardiac-type mucosa was identified; in 147 patients, the cardiac-type mucosa showed intestinal metaplasia. They were divided into 3 groups based on the extent of intestinal metaplasia commonly seen clinically: long segments (>3 cm), short segments (<3 cm), and limited to the gastroesophageal junction. The duration of symptoms, the status of the lower esophageal sphincter, the degree of esophageal acid exposure, and the time to clear a reflux episode were assessed in each group. RESULTS: The presence of intestinal metaplasia in cardiac-type mucosa was associated with the hallmarks of gastroesophageal reflux disease. The extent of intestinal metaplasia correlated strongly with the degree of esophageal acid exposure (r = 0.711; P <.001) and inversely with the lower esophageal sphincter pressure (r = 0.351; P <.001) and length (r = 0. 259; P =.002). Patients with a long segment of intestinal metaplasia (>3 cm) had longer duration of symptoms (16 years) than those patients with a segment of intestinal metaplasia less than 3 cm (10 years; P =.048) or those patients with intestinal metaplasia limited to the gastroesophageal junction (10 years; P =.01). CONCLUSION: The extent of intestinal metaplasia, that is, Barrett's esophagus, is related to the status of the lower esophageal sphincter and the degree of esophageal acid exposure.  相似文献   
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