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41.
Groups of 80 female rats were exposed to cigarette smoke from three types (code 13 = high tar, low nicotine; code 27 = low tar, medium nicotine; code 32 = high tar, high nicotine) of cigarettes in Maddox-ORNL smoking machines, eight cigarettes per day, 7 days per week, for up to 24 months. An additional group received sham exposures and a fifth group served as untreated controls. The sham-exposed animals had significantly lower body weights than the untreated controls. The smoke-exposed animals had significantly lower weights than the sham-exposed controls; the weights were lower for the code 27 and code 32 animals than for the code 13 animals during the second year of exposure. The survival of the code 13 animals was similar to that for the sham-exposed and untreated control group; survival times of the code 27 and code 32 animals were shorter. Body weight and survival reflected the high- and low-nicotine dose groups indicated by in vivo dosimetry measurements. Smoke-induced histopathologic lesions consisted primarily of pulmonary smoke granulomas; the smoke granulomas were less severe in the code 27 exposure group than in the groups exposed to smoke from code 13 or code 32 cigarettes. Additional changes included pulmonary alveolar epithelial hyperplasia, and squamous metaplasia and basal cell hyperplasia of laryngeal and tracheal epithelium. One primary epidermoid carcinoma was found in the lung of a code 27 rat. The rats tolerated the chronic exposures relatively well and certain of the smoke-induced lesions allowed differentiation between the different types of cigarettes.  相似文献   
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Unevenness in emergency psychiatry training is still an issue as borne out by a recent literature review. An emergency setting in a general hospital is described with its attendant problem areas for psychiatric residents' function and learning. An adaptable curriculum is reported that takes into account limits of time, finances, and faculty.  相似文献   
43.
Hemodynamic basis for human acute renal failure (vasomotor nephropathy)   总被引:1,自引:0,他引:1  
Oliguric acute renal failure in man is characterized by intense outer cortical vasoconstriction and a marked increase in preglomerular resistance. The degree of preglomerlar resistance change needed to cause the expected 50 to 80 percent fall in blood flow far exceeds the level that would totally abolish filtration. By contrast, equal 3.0-fold increases in both pre- and postglomerular resistance provide this same degree of ischemia but leave filtration very well maintained. Such a scenario seems unlikely, however, since it would entail a mere 15 to 25 percent decrease in preglomerular resistance vessel caliber rather than the extreme attenuation observed. By contrast, there are reasons to believe that preglomerular constriction may be accompanied by postglomerular vascular relaxation. In sum, unless cortical ischemia reflects precisely matched increases in pre- and postglomerular resistances, filtration failure is inevitable in human vasomotor nephropathy.  相似文献   
44.
Sixty-seven patients underwent 73 pectoralis major myocutaneous flap procedures for the immediate reconstruction of defects after resection of head and neck cancers. Thirty-six patients experienced a total of 50 complications for an overall complication rate of 54 percent. There were 3 instances of total flap necrosis, 9 of partial flap necrosis, 12 orocutaneous fistulas, 9 suture line separations, 8 neck wound complications, 1 donor site complication, and 8 mandibular replacement complications. Most complications were minor and did not require a second procedure for correction; however, 36 percent did require a second operation. Eight of 10 patients in whom a metal appliance was placed to restore mandibular continuity required the removal of that appliance due to either flap necrosis, fistula formation, or exposure. Based on our experience, we conclude that attention to flap design, operative technique, and post-operative management were useful in reducing the incidence of complications. We also conclude that a metal appliance was an unsatisfactory means of restoring mandibular continuity when utilized beneath a pectoralis major myocutaneous flap. Although the overall incidence of complications was high, the actual incidence of flaps failing to accomplish their intended purpose and requiring secondary repair was acceptable. The pectoralis major myocutaneous flap was reliable in the reconstruction of defects in the head and neck region.  相似文献   
45.
Our clinical experience, as well as literature review, indicate that the MSE may be more myth than method in contemporary psychiatry. Given the current common language available through DSM (III) and the APA Glossary, the MSE may well have enhanced potential as a practical clinical tool because it can be transferable, affordable, portable, and not machine dependent. Having intervened, as noted above, we intend to follow-up via clinical records, interview and questionnaire to determine whether more consistent notation by trainees is present and whether trainees have a shared concept as to form and clinical utility of the MSE.  相似文献   
46.
Seventeen consecutive patients underwent pull-through esophagectomy using blunt dissection from laparotomy and cervical incisions for carcinoma of the esophagus. Fifteen patients had a middle-third lesion while 2 patients had a distal-third lesion. The gastrointestinal tract was reconstructed using primary gastroesophagostomy in 15 patients and colon interposition in 2. Both the colon and stomach were placed through the posterior mediastinum. The surgical technique and results are described in detail. There were two major complications. One patient died of massive gastric hemorrhage on the eighth postoperative day in spite of emergency operation. Another patient sustained a tear of the membranous trachea at the time of blunt dissection. This was repaired through a right thoracotomy without difficulty. Esophagectomy using blunt dissection offered excellent palliation and resulted in little morbidity in our series. The shortened operating time, minimal blood loss, total lack of postoperative chest pain, minimal pulmonary complications, and the benefit of a cervical anastomosis are several advantages compared with the present surgical approaches.  相似文献   
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The case of an adult patient with congenital tricuspid stenosis is presented. The lesion was successfully corrected with valvular commissurotomy and repair of atrial septal defect. Use of two-dimensional echocardiography in diagnosis of congenital tricuspid stenosis is discussed.  相似文献   
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