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61.
<正>A (very) brief history of tension in nerve repair:Successful nerve repair is achieved by conveying as many axons successfully to their targets as possible.Typically,this is best achieved through a direct end-to-end repair under minimal tension (Millesi,1986).However,this is not feasible in most cases of trauma,where a segment of tissue damage must be excised and overcome.This has most commonly been addressed with the use of nerve grafts to bridge the gap.Autologous nerve grafts are cons...  相似文献   
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We have evaluated the effect of variation in aryl-tetralin lignans on the radioprotective properties of Podophyllum hexandrum. Two fractionated fractions of P. hexandrum [methanolic (S1) and chloroform fractions (S2)], with varying aryl-tetralin lignan content were utilized for the present study. The peroxyl ion scavenging potentials of S1 and S2 were found to be comparable [i.e. 45.88% (S1) and 41% (S2)] after a 48 h interval in a time-dependent study, whereas in a 2 h study, S2 exhibited significant (P < 0.05) antioxidant activity in different metal ion + flux states. In the aqueous phase, S2 exhibited non-site-specific reactive oxygen species scavenging activity, i.e. 73.12% inhibition at 500 mug ml(-1). S1 exhibited 58.40 +/- 0.8% inhibition (at 0.025 mug ml(-1)) of the formation of reactive nitrite radicals, comparable to S2 (52.45 +/- 0.825%), and also showed 45.01% site-specific activity (1000 mug ml(-1)), along with significant (P < 0.05) electron donation potential (50-2000 mug ml(-1)) compared to S2. Such activities of S1 could be attributed to the significantly (P < 0.05) higher levels of podophyllotoxin beta-d-glucopyranoside (16.5 times) and demethyl podophyllotoxin glucoside (2.9 times) compared with S2. Together, these findings clearly prove that aryl-tetralin lignan content influences the radiation protective potential of the Podophyllum fractions to a great extent.  相似文献   
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Neurofibroma is a benign nerve sheath tumor of the peripheral nervous system. A young male presented with complaints of gradually increasing breathlessness and heaviness on the right side of the chest, and percussion notes over the chest were impaired all over the right lung fields except the basal zone. Contrast-enhanced computed tomography scan of the thorax revealed a large heterogeneous mass occupying most of the right hemithorax. Intraoperatively, the huge mass measuring about 18 cm?×?13 cm?×?12 cm was seemed to arise from the right fourth intercostal space. Histopathology revealed a neurofibroma. Giant intrathoracic neurofibroma is very uncommon and its malignant potential should be evaluated.  相似文献   
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Worldwide increases in diabetes prevalence in the face of limited medical resources have prompted international interest in innovative healthcare delivery models. Project ECHO (Extension for Community Healthcare Outcomes) is a “telementoring” program which has been shown to increase capacity for complex disease management in medically underserved regions. In contrast to a traditional telemedicine model which might connect a specialist with one patient, the ECHO model allows for multiple patients to benefit simultaneously by building new expertise. We recently applied the ECHO model to improve health outcomes of patients with complex diabetes (Endo ECHO) living in rural New Mexico. We describe the design of the Endo ECHO intervention and a 4-year, prospective program evaluation assessing health outcomes, utilization patterns, and cost-effectiveness. The Endo ECHO evaluation will demonstrate whether and to what extent this intervention improves outcomes for patients with complex diabetes living in rural New Mexico, and will serve as proof-of-concept for academic medical centers wishing to replicate the model in underserved regions around the world.  相似文献   
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Ticagrelor is a cornerstone of modern antithrombotic therapy alongside aspirin in patients with acute coronary syndrome and after percutaneous coronary intervention. Adverse effects such as bleeding and dyspnea have been associated with premature ticagrelor discontinuation, which may limit any potential advantage of ticagrelor over clopidogrel. The randomized trials of ticagrelor captured adverse events, offering the opportunity to more precisely quantify these effects across studies. Therefore, a meta-analysis of 4 randomized clinical trials of ticagrelor conducted between January 2007 and June 2017 was performed to quantify the incidence and causes of premature ticagrelor discontinuation. Among 66,870 patients followed for a median 18 months, premature ticagrelor discontinuation was seen in 25%; bleeding was the most common cause of discontinuation followed by dyspnea. Versus the comparators, the relative risk of dyspnea-related discontinuation during follow-up was 6.4-fold higher, the relative risk of bleeding was 3.2-fold higher, and the relative risk of discontinuation due to any adverse event was 59% higher for patients receiving ticagrelor. Understanding these potential barriers to adherence to ticagrelor is crucial for informed patient-physician decision making and can inform future efforts to improve ticagrelor adherence. This review discusses the incidence, causes, and biological mechanisms of ticagrelor-related adverse effects and offers strategies to improve adherence to ticagrelor.  相似文献   
69.
ABSTRACT

The spread of HIV/AIDS is a major public health problem in military personnel in Africa. However, the epidemiological evidence regarding HIV/AIDS prevention practices among military personnel in Ethiopia remains unclear. The aim of this study was to investigate HIV/AIDS prevention practices among military personnel in Northwest Ethiopia. A cross-sectional study among military personnel (n?=?410) was conducted in Northwest Ethiopia in 2015. Data were collected using a pre-tested questionnaire. Multivariable logistic regression model was fitted to ascertain factors influencing participation in HIV/AIDS prevention programs. About one-fourth (24.6%) of the military personnel had multiple sexual partners, of whom 24.7% failed to use condoms regularly when having sex with non-regular sexual partners. Majority of the sample (n?=?355, 86.6%) participated in HIV/AIDS prevention programs. Military personnel who had multiple sexual partners were 6.3 times more likely to report history of non-participation in HIV/AIDS prevention programs (AOR?=?6.3, CI95?=?3.5–11.54). A considerable proportion of military personnel had multiple sexual partners with lower levels of condom utilization with non-regular sexual partners. The study further demonstrated misconceptions about HIV/AIDS in Ethiopian military personnel, which reduce their likelihood of participation in HIV/AIDS prevention programs. Health authorities need to strengthen and accelerate HIV/AIDS prevention programs focusing towards military personnel.  相似文献   
70.
BACKGROUND: Current guidelines stratify patients with a personal history of adenomas as low risk (ie, 1-2 small [<10 mm] adenomas at index colonoscopy) or high risk (> or =3 small adenomas or advanced adenoma at index colonoscopy) for recurrent advanced adenomas. Guidelines recommend longer intervals between surveillance colonoscopies for low-risk patients, but physicians frequently perform surveillance colonoscopy at shorter intervals for these patients. OBJECTIVE: Our purpose was to perform a meta-analysis about the incidence of advanced adenomas at 3-year surveillance colonoscopy among high- and low-risk patients. METHODS: Computer searches of MEDLINE, PREMEDLINE, and EMBASE were performed to identify appropriate studies. Study selection criteria were (1) study design--prospective or registry-based study, (2) study population--patients with a personal history of adenomas, and (3) intervention--completion of surveillance colonoscopy at an interval of > or =2 years. Data were extracted on (1) incidence of advanced adenomas at surveillance colonoscopy, (2) interval between colonoscopies, and (3) risk factors associated with recurrent adenomas. After the validity of study design was assessed and independent, duplicate data extraction was performed from selected trials, summary relative risks (RR) for the incidence of advanced adenomas at 3-year colonoscopy were calculated. RESULTS: Fifteen studies met study selection criteria, but only 5 studies stratified surveillance colonoscopy results according to findings at the index colonoscopy. Patients with > or =3 adenomas at index colonoscopy were more likely to have recurrent advanced adenomas than were patients with 1 to 2 adenomas: RR 2.52, 95% CI 1.07-5.97. Patients with adenomas with high-grade dysplasia at index colonoscopy were also at increased risk for recurrent advanced adenomas: RR 1.84, 95% CI 1.06-3.19. In the individual studies, increasing size of adenomas and increasing number of adenomas at index colonoscopy were the most commonly reported risk factors associated with recurrent advanced adenomas. No studies stratified surveillance colonoscopy results according to the definitions of low risk and high risk used in current guidelines. CONCLUSION: Few published studies stratify the incidence of advanced adenomas at surveillance colonoscopy according to index colonoscopy findings. In the future, large prospective studies or studies using pooled data from existing randomized controlled trial databases or polyp registries should be used to better define which patients are at low risk for advanced adenoma recurrence.  相似文献   
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