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61.
Brachial plexus traction injuries most frequently occur following acute flexion or extension of the neck. The symptomatology following this injury may be defined clearly into the anatomic patterns of upper trunk, lower trunk, posterior cord, medial cord, and lateral cord radiations. This injury is the most common cause of the neurogenic form of thoracic outlet syndrome and is frequently seen in conjunction with cervical spine disease as well as peripheral entrapment syndromes of the ulnar, radial, and medial nerves.  相似文献   
62.
本文研究了唐松草新碱在水溶液中的氧化降解动力学。考查了pH值、离子强度、温度和氧含量的影响,水溶液中的氧化降解速率常数由荧光法测定。结果表明,唐松草新碱在过量氧存在下,其氧化降解反应服从假一级反应动力学方程式,速率常数可由下式表示:其速率常数主要受介质的pH值和氧含量的影响,在pH 7.2条件下没有观测到原盐效应。  相似文献   
63.
64.
Gravity-induced stresses by an obturator prosthesis   总被引:1,自引:0,他引:1  
Recontruction after surgical resection of tumors of the maxillae and paranasal sinuses is difficult. In addition to the intermittent forces encountered during function, the prosthesis is subjected to the constant force of gravity. This investigation photoelastically studies the gravity-induced stresses transmitted to the remaining oral structures by various obturator prosthesis framework designs. Frameworks which used I-bar and circumferential retainers with buccal retention were most severe, while the swinglock and light wire retainers were intermediate in generated stress.  相似文献   
65.
66.
Nocardiosis of the lung: chest radiographic findings in 21 cases   总被引:4,自引:0,他引:4  
Feigin  DS 《Radiology》1986,159(1):9-14
Pulmonary manifestations of nocardial infection were present in 21 patients, with microbiologic proof in all and pathologic proof in 12. An analysis of the findings in these patients, combined with a review of previous reports of nocardiosis, suggests several important conclusions for radiologists. First, nocardiosis may occur in otherwise healthy persons but is most common in compromised patients, especially those being treated with anti-inflammatory agents, particularly corticosteroids, for chronic obstructive pulmonary disease and other systemic diseases. As pathologic manifestations are both suppurative and granulomatous, the chest radiographic manifestations are pleomorphic and not specific. Consolidations and large irregular nodules, often cavitary, are most common; nodules, masses, and interstitial patterns also occur. Pleural effusions are quite common, and lymph nodes may be enlarged. Difficulty and slowness of culture growth, along with the lack of a serologic test for nocardiosis, necessitate its inclusion in the differential diagnosis for both compromised and noncompromised patients in whom an apparent pulmonary infection cannot be rapidly diagnosed.  相似文献   
67.
The proper choice of antibiotic for Clostridium perfringens infections in patients allergic to penicillin is not clear; the usual recommendations and recent in vitro studies disagree. We tested the susceptibility of 57 strains of C. perfringens to eight penicillins, seven cephalosporins, two tetracyclines, clindamycin, chloramphenicol, and rifampin by the agar dilution method. All strains were inhibited by (per milliliter) 4 mug or less of any of the penicillins, chloramphenicol, or clindamycin and 8 mug or less of any of the cephalosporins tested. Penicillin G and amoxicillin inhibited all strains at 0.12 mug or less per ml. Only 54% of the strains were inhibited by 1 mug of tetracycline per ml. Penicillin G remains the drug of first choice for infections with C. perfringens; it need not be added to a regimen containing a penicillinase-resistant penicillin given parenterally in high doses. The cephalosporins should be considered as alternative drugs for penicillin-allergic patients. Clindamycin and chloramphenicol are also effective. Tetracyclines cannot be depended upon in clostridial infections without in vitro testing, which is impracticable for initial empirical therapy.  相似文献   
68.
In recent years, fluorescent cholangiography using Indocyanine green (ICG) dye has been used to aid identification of structures during robotic cholecystectomy. We sought to compare cholecystectomy with ICG dye versus laparoscopic cholecystectomy at an inner-city academic medical center. Between January 2013 and July 2016, we identified 287 patients of which 191 patients underwent laparoscopic cholecystectomy and 96 patients underwent robotic cholecystectomy with ICG dye. Preoperative risk variables of interest included age, sex, race, body mass index (BMI), and acute cholecystitis. Primary outcome of interest was conversion to open procedures while secondary outcome was length of stay. The two groups were similar in their BMI (31.98 vs. 31.10 kg/m2 for the laparoscopic and robotic, respectively, p = 0.32). The laparoscopic group had a greater mean age compared to the robotic group (47.77 vs. 43.61 years, p = 0.04). There was no significant difference in sex and emergency surgery between the two groups. Fewer open conversions were found in the robotic than the laparoscopic group [2 (2.1%) vs. 17 (8.9%), p = 0.03]. In multiple logistic regression, robotic cholecystectomy with ICG also showed a lower risk of conversion compared to laparoscopic cholecystectomy, but the difference did not reach statistical significance (OR 0.42, 95% CI 0.11–1.65, p = 0.22). ICG fluorescent cholangiography during robotic cholecystectomy may contribute to proper identification of biliary structures and may reduce the rates of open conversion. The preliminary results of fewer open conversions are promising. Further studies with a large randomized prospective controlled study should be taken for further evaluation.  相似文献   
69.
SUMMARY Dysbaric symptoms following ascent from a scuba dive are due to symptomatic nitrogen or air emboli with clear patterns of associated injury. This case report highlights an unusual presentation of dysbaric injury treated successfully with a prostacyclin analogue.  相似文献   
70.
BACKGROUND: Several techniques for percutaneous catheter-based radiofrequency ablation of left atrial myocardium have been described. Each is potentially limited by anatomic inaccuracy, radiation requirement, cardiac/extracardiac collateral damage, proarrhythmia, lesion impermanence, or unclear procedural endpoint. OBJECTIVES: The purpose of this study was to describe a new technique that may address some of these limitations. METHODS: In 200 consecutive patients with atrial fibrillation (AF), complete ablative encircling of right and left pulmonary venous vestibules was performed using radiofrequency energy applied via a standard ablation electrode. Lesions were guided by a collaborative nonfluoroscopic imaging strategy involving intra-left atrial echocardiography and CARTO. A discrete procedural endpoint was sought: complete electrical isolation of all myocardium subtended by the encircling lesions. RESULTS: After a procedure in which the total fluoroscopy time averaged 6 minutes, isolation was achieved on the left and right sides in 198 and 199 patients, respectively. In addition to the vestibule-encircling lesions, isolation required one or more additional focal lesions within the subtended myocardial territory in the majority of left vestibules and in a minority of right vestibules. Significant procedural morbidity was observed, including cerebroembolism resulting in death and mesenteric embolism resulting in hemicolectomy. Procedural success, defined at 2 years after the initial procedure and requiring no interim procedure, antiarrhythmic drug therapy, or apparent arrhythmia burden, was observed in a significantly greater proportion of patients with a paroxysmal (87%) than persistent AF (60%) syndrome. Only a small proportion of patients with recurrent AF had recurrence of conduction in previously isolated zones. CONCLUSION: This technique may have advantages over those previously reported, including improved anatomic accuracy, improved lesion safety and efficacy, and diminished radiation exposure.  相似文献   
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