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41.
Long thoracic nerve: anatomy and functional assessment   总被引:2,自引:0,他引:2  
BACKGROUND: The anatomy and function of the long thoracic nerve are not fully understood. The purposes of this study were to clarify the anatomy of the long thoracic nerve and to propose a clinical test to assess the function of the upper division of the long thoracic nerve. METHODS: The long thoracic nerve and the serratus anterior muscle were studied in fifteen fresh cadavera. Six patients had an operation to treat a brachial plexus injury, and the long thoracic nerve was electrically stimulated. The resulting shoulder motion was then observed. RESULTS: The long thoracic nerve was formed by branches arising from the C5, C6, and C7 nerve roots. The C5 and C6 branches joined beneath the scalenus medius muscle to form the upper division of the long thoracic nerve, which was located 1 cm posteriorly and superiorly to the upper trunk origin. The union of the upper division with the branch from C7 occurred caudally, in the axillary region. Two branches from the upper division of the long thoracic nerve to the upper portion of the serratus anterior muscle were consistently identified. After electrical stimulation of the upper division branches, shoulder protraction was observed. CONCLUSIONS AND CLINICAL RELEVANCE: In the supraclavicular region, the long thoracic nerve has a trajectory parallel to the brachial plexus, which is contrary to the schematic representation in most textbooks. The upper division of the long thoracic nerve can be assessed by the shoulder protraction test.  相似文献   
42.
Implant migration can be accurately quantified by model‐based Roentgen stereophotogrammetric analysis (RSA), using an implant surface model to locate the implant relative to the bone. In a clinical situation, a single reverse engineering (RE) model for each implant type and size is used. It is unclear to what extent the accuracy and precision of migration measurement is affected by implant manufacturing variability unaccounted for by a single representative model. Individual RE models were generated for five short‐stem hip implants of the same type and size. Two phantom analyses and one clinical analysis were performed: “Accuracy‐matched models”: one stem was assessed, and the results from the original RE model were compared with randomly selected models. “Accuracy‐random model”: each of the five stems was assessed and analyzed using one randomly selected RE model. “Precision‐clinical setting”: implant migration was calculated for eight patients, and all five available RE models were applied to each case. For the two phantom experiments, the 95%CI of the bias ranged from ?0.28 mm to 0.30 mm for translation and ?2.3° to 2.5° for rotation. In the clinical setting, precision is less than 0.5 mm and 1.2° for translation and rotation, respectively, except for rotations about the proximodistal axis (<4.1°). High accuracy and precision of model‐based RSA can be achieved and are not biased by using a single representative RE model. At least for implants similar in shape to the investigated short‐stem, individual models are not necessary. © 2015 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:903–910, 2016.
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43.
Oxidative stress aggravates several long‐term complications in diabetes mellitus. We evaluated the effectiveness of the oral administration of antioxidants (vitamins E and C, 40 and 100 mg/kg b.w., respectively) on skin wound healing acceleration in alloxan‐induced diabetic mice. Mice were wounded 30 days after the induction of diabetes. Antioxidants were effective in preventing oxidative stress, as assessed by TBARS. The enzymes catalase, glutathione reductase, glutathione peroxidase, and superoxide dismutase were increased in diabetics on the 3rd day post‐wounding; catalase and glutathione peroxidase remained still augmented in diabetics after 14th day postwounding, and the treatment with vitamins restored their activities to control. After 3 days, diabetic mice showed lower infiltration of inflammatory cells (including CD11b+ and Ly6G+ cells) and reduced levels of KC, TNF‐α, IL‐1β, and IL‐12 p40 when compared with control mice. The treatment restored cytokine levels. After 14 days, diabetic mice showed late wound closure, persistent inflammation and delayed reepithelialization, accompanied by an increase in MIG+/CD206? macrophages whereas CD206+/MIG? macrophages were decreased. Cytokines IL‐12p40, TNF‐α, IL‐1β, and KC were increased and normal levels were restored after treatment with antioxidants. These results suggest that oxidative stress plays a major role in diabetic wound healing impairment and the oral administration of antioxidants improves healing by modulating inflammation and the antioxidant system with no effect on glycemia.  相似文献   
44.
The aim of this study was to evaluate the influence of laser photobiomodulation in cutaneous healing of rats under a hyperlipidic diet. Forty-eight Wistar Albinus rats, weaned, received standard diet (SD) or hyperlipidic diet (HD) for 20 weeks. The groups were divided into SD rats and HD rats, SD-irradiated rats (LSD), and HD-irradiated rats (LHD). Standard cutaneous wound (1 cm2) was created on the dorsum of each rat. The irradiation started immediately after surgery and every 48 h for 7 or 14 days (λ660 nm, 40 mW, 6 J/cm2, ? 0,04 cm2, CW), when they were killed under deep anesthesia. The specimens were removed, routinely processed, stained with hematoxylin/eosin (H/E), and evaluated by light microscopy. Rats fed with hyperlipidic diet had greater intensity in the inflammatory process and prolonged hyperemia. At day 7, the intensity of inflammation was reduced in LSD and LHD groups when compared to their control groups, SD (p?=?0.002) and HD (p?=?0.02). There was an increase in fibroblast proliferation and collagen deposition, especially in the LHD group. At day 14, the HD group presented more intensive hyperemia than the SD group. It can be concluded that the hyperlipidic diet modified the inflammation pattern in wound healing and that laser light has a positive biomodulative effect on the healing process only in early stages.  相似文献   
45.
Salivary gland tumors consist of a group of heterogeneous lesions with complex clinicopathological characteristics and distinct biological behaviors. Worldwide series show a contrast in the relative incidence of salivary gland tumors, with some discrepancies in clinicopathological data. The main aim of this study was to describe demographic characteristics of 599 cases in a population from Central Brazil over a 10-year period and compare these with other epidemiological studies. Benign tumors represented 78.3% of the cases. Women were the most affected (61%) and the male:female ratio was 1:1.6. Parotid gland tumors were the most frequent (68.5% of cases) and patient age ranged from 1 to 88 years-old (median of 45 years old). The most frequent tumors were pleomorphic adenomas (68.4%) and benign tumors were significantly more frequent in the parotid (75.9%), while malignant tumors were more frequent in the minor salivary glands (40%) (P < 0.05). In conclusion, women and the parotid gland were the most affected and pleomorphic adenoma was the most frequent lesion, followed by adenoid cystic carcinoma and Warthin’s tumor.  相似文献   
46.
The gallbladder is rarely the site of distant metastases and in most cases malignant melanoma is the primary tumor. We report a case of a 64-year-old man with a gallbladder metastasis secondary to a renal cell carcinoma. Renal cell carcinoma has a tendency toward metastatic disease, the most notable features of this tumor being its unusual pattern of metastatic disease. Pre-operative imaging studies are often futile in the differentiation between primary and secondary tumors of the gallbladder. Since primary tumors of the gallbladder often coexist with gallstones, a polypoid lesion in an acalculous gallbladder is more consistent with metastasis than a primary tumour. If feasible, surgical resection of the gallbladder is mandatory because it could guarantee better chances of survival for patients with metastatic renal carcinoma.  相似文献   
47.
We performed a systematic review of the literature on the diagnosis and treatment of secondary aortoenteric fistulas (AEF). A MEDLINE search was performed of articles published in English or Spanish between January 1991 and August 2006. Diagnostic methods, treatment modalities and the results of surgical treatment were analyzed. The most frequent first aortic surgery associated with AEF was repair of abdominal aortic aneurysm (54.31%). The most common form of presentation was gastrointestinal bleeding. Repair through in situ prosthetic replacement had the lowest early mortality rates (8-13.3%) compared with graft excision and extraanatomic revascularization (18.2-44%). AEF is a serious entity and diagnosis requires a high index of suspicion based on clinical findings and indirect data from imaging techniques (computed tomography). The most appropriate therapeutic option continues to be controversial.  相似文献   
48.
49.
BACKGROUND: Since 2002, the worldwide Study for Monitoring Antimicrobial Resistance Trends (SMART) has tracked resistance patterns among aerobic and facultative gram-negative bacilli isolated from patients with intra-abdominal infections. Escherichia coli has been by far the most frequently isolated species. METHODS: Antimicrobial susceptibilities for consecutive non-duplicate isolates of aerobic and facultative gram-negative bacilli recovered from intra-abdominal infections were determined by standard broth microdilution techniques. A subanalysis was performed for E. coli isolates from the first three years of the study. RESULTS: A total of 7,002 E. coli isolates were recovered, most commonly from the peritoneal cavity followed by the biliary tract. Susceptibility rates to the 12 antimicrobial agents tested differed among geographic regions, with isolates from Asia/Pacific generally having the highest resistance rates. Overall, extended-spectrum beta-lactamase (ESBL)-producers had a more antibiotic-resistant profile than non-ESBL-producers but usually were susceptible to the carbapenems and amikacin. Community-acquired E. coli strains comprised slightly more than one-half of the isolates and were susceptible to the agents tested more frequently than were hospital-acquired E. coli. CONCLUSIONS: The prevalence of antimicrobial resistance among E. coli isolated from intraabdominal infections is not inconsequential, especially in the Asia/Pacific region. The carbapenems and amikacin were consistently active in vitro against E. coli isolates worldwide, including ESBL-producers.  相似文献   
50.
OBJECTIVE: Assessment of myocardial viability by 99mTc-Sestamibi Single Photon Emission Computerized Tomography (SPECT) has been suggested as a more readily available and cheaper alternative to Positron Emission Tomography (PET) with 13N-ammonia (NH3) and 18F-fluoro-deoxy-glucose (FDG). We hypothesized that a semi-quantitative evaluation by SPECT could delineate myocardial viability with an acceptable concordance to PET. DESIGN: Fifty patients (age 57+/-7 years; ejection fraction 28 +/- 8%), with ischemic cardiomyopathy, underwent SPECT and PET imaging in random order. Viability by SPECT was defined as a defect size <50% of the segment area, or a defect representing > or =50% of the segment but with a mean activity > or =50% of peak activity. PET viability was defined as a perfusion score >2 and FDG score < or =2 (five-point scale, 0 = normal, 4 = absent activity). RESULTS: By segmental comparison to PET. SPECT yielded a sensitivity and specificity of 87% and 82% for detection of viable myocardium. The positive and negative predictive values were 96% and 58%, respectively. CONCLUSION: In patients with severe ischemic cardiomyopathy 99mTc-Sestamibi SPECT can delineate viable myocardium with an acceptable segmental concordance to NH3/FDG PET.  相似文献   
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