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991.
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993.
S Takaishi K Isono Y Nishibayashi Y Tanaka T Morikawa A Masuda B Ahn Y Honda 《Respiration; international review of thoracic diseases》1990,57(5):293-298
We studied the breathing pattern and pulmonary function at rest, and ventilatory responses to progressive hypoxia and hypercapnia in 7 awake patients who had undergone esophageal-carcinoma resection with sectioning of the right pulmonary vagal branch by lymphadenectomy. Twelve control patients, who had received the same surgery without vagotomy, were also studied by the same protocol. Two months after the operation, both patient groups demonstrated substantial depressions in FVC and FEV1.0, and slight augmentations in breathing frequency, minute ventilation, and occlusion pressure at 0.2s (P0.2) at rest. In the vagotomized group, the occlusion pressure responses to hypercapnia (delta P0.2/delta PaCO2) and hypoxia (delta P0.2/delta SaO2) in terms of response curve slope increased from 1.3 +/- 1.2 to 1.9 +/- 1.1 cm H2O/Torr and from 0.29 +/- 0.19 to 0.88 +/- 0.53 cm H2O/% (p less than 0.05), respectively. Contrary to the vagotomized patients, the nonvagotomized control group exhibited no significant changes in ventilatory chemosensitivities. Furthermore, when comparing the control and vagotomized groups, postoperative ventilatory chemosensitivity responses in terms of both hypercapnic and hypoxic occlusion pressure responses were significantly higher in the latter. We suggest that (1) due to the development of the substantial mechanical limitation in pulmonary functions, the Hering-Breuer inflation reflex became activated after surgery, and (2) a diminished Hering-Breuer reflex effect to inhibit the respiratory centers by unilateral vagotomy may have resulted in augmented ventilatory chemosensitivities. 相似文献
994.
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996.
A heterotopic salivary gland (HSG) in the lower neck is an unusual developmental anomaly rarely encountered by the dermatologist. Klimko and Horanyi (1) reported the first histologically documented case of HSG in the lower neck in 1958. To our knowledge, fewer than 100 such cases have been reported in the literature to date. The origin of HSG in the lower neck seems to be closely associated with the branchial apparatus. Because this condition is rarely encountered, dermatologists should be well informed about the clinical manifestations, development of various malignancies, and the differential diagnosis of HSG. 相似文献
997.
Jin Hyoung Won Sung Ku Ahn Seung Hun Lee Soo-Chan Kim Soo Im Choi 《The Journal of dermatology》1993,20(6):381-383
We report a 20-year-old-Korean woman with a congenital giant pigmented nevus and angiolipoma. She was admitted our department with a large, dark, pigmented lesion on the right flank and abdomen and a slowly growing mass on the right flank area since birth. On biopsy, the specimen taken from the giant pigmented patch showed typical findings of compound nevus. The right flank mass was surgically removed. The specimen was composed of mature fat cells with an increased vascular component. These findings are compatible with angiolipoma. 相似文献
998.
Loads in the spinal structures during lifting: development of a three-dimensional comprehensive biomechanical model 总被引:1,自引:0,他引:1
J. S. Han V. K. Goel J. Y. Ahn J. Winterbottom D. McGowan J. Weinstein T. Cook 《European spine journal》1995,4(3):153-168
Summary Epidemiological studies have shown that loads imposed on the human spine during daily living play a significant role in the onset of low back pain. The loads applied to the lumbar spine are shared by a number of structures: muscles; posterior elements, including facets and ligaments; and the disc of a ligamentous motion segment. In vivo, it is not practical to determine forces in these structures using experimental techniques. Biomechanical models, based on an optimization technique or electromyographic activities of the trunk muscles, have been proposed to predict forces in the load transmitting structures. The mathematical models reported in the literature are based on information collected from a wide variety of sources, of which the subject that takes part in the experiment is only one. The present study describes techniques developed in our laboratory to collect from the subjects themselves all the data needed for the formulation of a biomechanical model. The results demonstrated that back lifting with 0 N (no load), 90 N, and 180 N in the hands created maximum external flexion moments respectively of 109.6 Nm, 137.9 Nm, and 161,7 Nm, at the L3–4 disc level. The corresponding external axial compression forces on the disc were 469.5 N, 511.8 N, and 601.5 N. The predicted disc compression varied from 3.4 to 5.0 times the body weight. In comparison to the static lifting mode, the dynamic lifting task caused an increase in the disc compression force ranging from 15.8% to 39.4% depending on the load being lifted (e.g., 3256 N for the dynamic mode vs. 2516 N for the static mode when the subject lifted 90 N). The salient features of the entire protocol developed by the authors and the need for further improvements are also presented. 相似文献
999.
Chan-Seok Moon Zuo-Wen Zhang Shinichiro Shimbo Takao Watanabe Deog-Hwan Moon Chae-Un Lee Byung-kook Lee Kyu-Dong Ahn Se-Hoon Lee Masayuki Ikeda 《International archives of occupational and environmental health》1998,71(4):251-256
Objective: The present study was initiated to investigate the validity of cadmium (Cd) and lead (Pb) in urine in comparison with the
metals in blood as a biological marker of nonoccupational exposure of general populations to these metals as environmental
pollutants. Design: Peripheral blood samples, morning spot-urine samples, and 24-h total food duplicate samples were collected from 107 nonsmoking
women (aged 30–59 years) in four urban and rural survey sites in Korea. Methods: Portions of the samples were digested by heating in the presence of mineral acids, and the digests were analyzed for Cd and
Pb by graphite furnace atomic absorption spectrophotometry. The metal concentrations in urine were adjusted for creatinine
concentration and a specific gravity of 1.016. The analyte levels were evaluated on an individual basis (n = 107) and also on a group basis, i.e., in terms of geometric means for the survey sites (n = 4). Results: Cd in urine correlated with Cd in blood on an individual as well as survey-site basis and tended to correlate with Cd in
food duplicates on a group basis. The correlation of Pb in urine with Pb in blood was weaker than that of Cd in urine with
Cd in blood when evaluated on an individual and survey-site basis. Pb in urine correlated with Pb in food duplicates either
weakly or even negatively when examined on a survey-site basis. Conclusions: Cd in urine proved to be valid as a biological marker of environmental exposure of general populations, whereas less support
was obtained for Pb in urine as an exposure marker.
Received: 5 May 1997 / Accepted: 28 August 1997 相似文献
1000.
Ji Hoon Shin Kyu-Bo Sung Hyun-Ki Yoon Gi-Young Ko Kyoung Won Kim Sung-Gyu Lee Shin Hwang Chul-Soo Ahn Ki-Hun Kim Deok-Bog Moon Ho-Young Song Tae-Yong Ha 《Liver transplantation》2006,12(2):269-276
Middle hepatic vein (MHV) reconstruction is performed to drain the right paramedian sector to prevent hepatic venous congestion (HVC). The aim of the present study was to evaluate endovascular stent placement in patients with stenosed and/or occluded interposition vein graft (IVG) to segment V hepatic vein (V5) and segment VIII hepatic vein (V8) after living-donor liver transplantation (LDLT). The procedure was performed in 11 recipients; 7 underwent it within 24 hours of LDLT. The following parameters, including technical success, clinical success, complications, patient survival data, and serial computed tomography (CT) findings during follow-up, were documented retrospectively. Technical success was defined as both successful stent placement and resolution of stenosis or occlusion with copious flow of contrast medium through the stent, while clinical success was defined as both improvement of liver function tests (LFTs) and reduction or disappearance of hepatic low-attenuation areas on follow-up CT scans taken within 1 week of stent placement. Technical success was achieved in 10 of 11 patients (91%), and clinical success was achieved in 9 of 11 patients (82%). Acute thrombotic occlusion of the stent-inserted hepatic vein occurred in 1 patient 1 day following stent placement. During the mean follow-up period of 468 days (range, 13-891 days), 9 patients survived and 2 patients died. No death was directly related to stent placement or its related complications. The low-attenuation area in the involved hepatic segment V (S5) and/or VIII (S8) area prior to stent placement disappeared completely on follow-up CT scans performed at 3-12 days (mean, 5.4 days) after stent placement in all 9 patients with clinical success. No attenuation change occurred even in cases with chronic occlusion of the stent-inserted hepatic veins. In conclusion, though IVG to V5 and V8 remains controversial, the treatment of their stenosis or occlusion is safe and effective, even during their immediate postoperative period. 相似文献