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21.
R T Pham M Sung C R Dawson J Schachter 《Investigative ophthalmology & visual science》1990,31(7):1367-1373
The development and testing of candidate vaccines for trachoma are constrained because only humans and nonhuman primates are susceptible to conjunctival infection with Chlamydia trachomatis. Guinea pig inclusion conjunctivitis (GPIC), an analogous disease of guinea pigs, provides a useful, less expensive model to study ocular chlamydial infections. GPIC is caused by a Chlamydia psittaci strain whose external constituents are very similar to those of C. trachomatis. To develop a better model for studying GPIC immunity, conjunctival pockets were established under the abdominal skin of guinea pigs by subcutaneous implantation. Up to six implants could be produced in each animal. The success rate of implantation was 79.0% (n = 148). These pockets were then infected with GPIC. The organism was recovered from the autografts indicating local replication, and tests for serum antibody by microimmunofluorescence showed production of GPIC-specific antibody of IgG and IgM classes after infection. There was minimal antibody response after moderate inoculating doses to the implants, and the titers increased more slowly than after eye infection with GPIC; with higher concentration of the inoculum, however, the antibody response increased to the same levels as with the ocular challenge but more slowly. Inoculation of pockets with GPIC also produced acute inflammatory changes in infected autografts (n = 101). Histologic examination of infected grafts showed chlamydial inclusions in epithelial cells and significant infiltration with lymphocytes and polymorphonuclear cells. Subcutaneous autografts may provide a useful model for chronologic studies of chlamydial infection. The delayed immunologic response, however, suggests that these pockets of implanted epithelium do not have full access to the immune system. 相似文献
22.
Jin Woo Kim M.D. Ho Shik Kim M.D. In Kyung Kim M.D. Mee Ran Kim M.D. Eun Young Cho B.S. Heung Kee Kim M.D. Joon Mo Lee M.D. Sung Eun Namkoong M.D. 《Gynecologic oncology》1998,69(3):230-236
Transforming growth factor-β1 (TGF-β1) is known to be a potent growth inhibitor for many cell types, including most epithelial cells. In skin keratinocytes, TGF-β1 has been shown to inhibit growth and to rapidly reduce c-mycexpression. However, the molecular mechanism of TGF-β1 action on cell growth of cervical carcinoma has not yet been elucidated. We thus assessed the effect of TGF-β1 on the growth of cervical carcinoma cell lines. Two cervical squamous carcinoma cell lines, CUMC-3 and CUMC-6, were incubated with varying concentrations of TGF-β1, and growth inhibition was evaluated with tetrazolium-based colorimetric assay. After culture in TGF-β1 for 24 h, inhibition of growth was detected in a dose-dependent manner at concentrations of 0.1–10 ng/ml in both cell lines. This effect of TGF-β1 on cultured carcinoma cells was associated with apoptotic process including oligonucleosomal ladder DNA and apoptotic body formations. Northern blot analysis revealed c-mycmRNA expression was suppressed by 10 ng/ml of TGF-β1 following 3 h of treatment in both cell lines. Western blot analysis showed that the level of p27Kip1protein was increased after TGF-β1 treatment in both cell lines. These results suggest that the mechanisms by which TGF-β1 inhibits the growth of cervical carcinoma are complex and may include effects on down-regulation of c-mycgene, and overexpression of p27Kip1protein. 相似文献
23.
扩大的椎板间开窗治疗腰椎间盘突出伴侧隐窝狭窄(附140例报告) 总被引:1,自引:0,他引:1
本组采用的扩大的椎板开窗术治疗腰椎间盘突出合并侧隐窝狭窄140例。结果全部优良,与适应症严格选择和手术损伤小有关。强调切除卡压神经根的侧隐窝后壁外侧,即上关节突的冠状面.不失其脊椎三柱系统的三角结构。俯卧位头低足高,可减少硬膜囊张力避免负损伤。切除棘突下椎板时,用神经拉勾代替神经剥离器易于分离黄韧带,用90度的椎板咬骨钳斜向棘突方向,可满意地切除该部份椎板黄韧带,并可刮切椎板内层。神经根周围滴入醋酸炎舒松A2-3ml,术后疼痛锐减。减压窗口置盖明胶海绵有其争议,作者实践体会放置害处不大,要求病人有“护腰”意识。 相似文献
24.
Yeong Shik Kim Kyung Shin Park Ho Koon Park Sung Whan Kim 《Archives of pharmacal research》1994,17(5):337-342
Carbohydrate analysis is important in studying structure and activity of complex polysaccharides. New analytical method was
applied to get an information on the composition of polysaccharides showing antitumor activity. Monosaccharides were labeled
with 7-amino-1,3-naphthalenedisulfonic acid (7-AGA) by reductive amination and separated by HPLC. Five kinds of polysaccharides
fromBasidiomycetes were hydrolyzed and analyzed in combination with electrophoresis and HPLC. At the same time, alditol acetate derivatives
were prepared and analyzed by gas chromatography. Two different techniques using different derivatization methods showed very
similiar results. The monosaccharides fromCoriolus versicolor andLentinus eodes were mainly composed of D-glucose, while those fromGanoderma lucidium andCordyceps militaris were glucose and galactose.Phellinus linteus composed of glucose, galactose, mannose, arabinose and fucose. The HPLC method with fluorescence detector was very sensitive
compared to other methods. 相似文献
25.
Oral and dental manifestations in diabetic and nondiabetic uremic patients receiving hemodialysis. 总被引:2,自引:0,他引:2
Shu-Fen Chuang Junne-Ming Sung Shih-Chen Kuo Jeng-Jong Huang Su-Yuan Lee 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2005,99(6):689-695
OBJECTIVE: The aim of this study was to examine the dental condition and oral manifestations in diabetic and nondiabetic uremic patients undergoing hemodialysis. STUDY DESIGN: A total of 128 patients undergoing hemodialysis therapy were classified into the diabetic and nondiabetic groups and examined for uremic oral manifestations, dental caries, and the periodontal status. All the patients received predialytic salivary pH examination. In the diabetic group, the correlation between oral findings and glycemic controlled levels, which was collected based on Hb A1C values, were further studied. RESULTS: The diabetic group exhibited significantly higher prevalence of caries and more severe dry mouth, taste change, and mucosa pain than the nondiabetic group. The diabetic group tended to have lower predialytic salivary pH, and patients with poor glycemic control (ie, Hb A1C > 9%) showed higher incidence of dry mouth, mucosal pain, and tongue coating. However, the DMFT and CPI index were not associated with glycemic control in the diabetic group. CONCLUSIONS: This study reveals that diabetic uremic patients undergoing maintained hemodialysis exhibited a potentially higher risk for dental decay and xerostomia. Lower salivary pH and poor glycemic control may affect oral manifestations. Further research is needed to clarify the combined influence of diabetic nephropathy on oral health. 相似文献
26.
Hong Kwan Kim Young Tae Kim Sook Whan Sung June Dong Park Chang Hyun Kang Joo Hyun Kim Yong Jin Kim 《European journal of cardio-thoracic surgery》2004,25(6):1065-1071
Objectives: Congenital tracheal stenosis is a rare disease. Various methods for treatment exist but there is still much debate as to the appropriate surgical procedure. We present our surgical experiences of patch tracheoplasty and slide tracheoplasty as viable methods for the treatment of congenital tracheal stenosis. Methods: From 1994 to 2002, 13 patients were diagnosed with congenital tracheal stenosis. Eight patients (7 symptomatic and 1 asymptomatic) had their stenosis corrected, three by means of pericardial patch tracheoplasty, four by slide tracheoplasty, and one by resection and anastomosis. Concomitant operations were performed on six patients to treat congenital cardiovascular disease. Five patients showing no significant symptoms did not undergo tracheal surgery and received only cardiac procedures. A retrospective review of the hospital course, complications, and long-term results was conducted. Results: Among the patch tracheoplasty group, every patient suffered from granulation tissue formation. One patient died of respiratory acidosis and one was hospitalized due to recurrent granulation tissue, which required frequent bronchoscopy. The third patient from this group is free of all symptoms. Among the slide tracheoplasty group, one patient died of anastomosis disruption. The three remaining patients are alive and well. The one patient who received resection and anastomosis is alive without symptoms. Conclusions: Surgical repair of long-segment congenital tracheal stenosis exhibited high mortality and morbidity rates. Every patient that underwent pericardial patch tracheoplasty suffered from troublesome granulation tissue. As slide tracheoplasty provided relatively good results in the short and mid-term follow-up periods, it seems to be a preferred method for the treatment of long-segment congenital tracheal stenosis. 相似文献
27.
Dong Hwee Kim Yoon Kyoo Kang Miriam Hwang Ho Sung Jo Ki Hoon Kim 《Clinical neurophysiology》2004,115(5):1021-1026
OBJECTIVE: To evaluate the usefulness of the TenElectrodes, a new stimulator for inching test, in the diagnosis and localization of ulnar neuropathy at the elbow (UNE). METHODS: Sixty-two ulnar nerves in 40 control subjects and 24 ulnar nerves in 23 patients with typical symptoms and signs of UNE were studied. The inching test of ulnar motor nerve using TenElectrodes was done along 8 cm across the elbow in the extended position. RESULTS: In the inching test of the control group, the mean segmental latency difference was 0.19+/-0.08 ms. Maximal latency difference over a 1 cm segment did not exceed 0.40 ms in any of the controls but exceeded 0.5 ms or more in all clinical UNE patients. In all UNE patients, the lesion sites were identified by the inching test using TenElectrodes: the retroepicondylar groove (54.2%), the humeroulnar arcade (29.2%), and dual compression (16.6%). CONCLUSIONS: TenElectrodes is a useful stimulator for the inching test in the diagnosis of UNE. The precise localization of compression was possible in all patients with UNE and the most common site was the retroepicondylar groove. 相似文献
28.
29.
Steven JY Wang Claire Cornick Jacqueline O'Dowd Michael A Cawthorne Jonathan R S Arch 《Lipids in health and disease》2007,6(1):2
Background
Mice that lack acyl CoA:diacylglycerol acyltransferase (Dgat1 -/- mice) are reported to have a reduced body fat content and improved glucose tolerance and insulin sensitivity. Studies so far have focussed on male null mice fed a high fat diet and there are few data on heterozygotes. We compared male and female Dgat1 -/-, Dgat1 +/- and Dgat1 +/+ C57Bl/6 mice fed on either standard chow or a high fat diet. 相似文献30.
Duk Hyun Sung Joon Young Choi Du-Hwan Kim Eun-Sang Kim Young-Ik Son Young-Seok Cho Su Jin Lee Kyung-Han Lee Byung-Tae Kim 《Journal of nuclear medicine》2007,48(11):1790-1795
The purpose of this study was to investigate whether (18)F-FDG PET/CT is useful for localizing dystonic cervical muscles in patients with idiopathic cervical dystonia (ICD) by comparing disease severity before and disease severity after botulinum toxin (BT) injection into hypermetabolic muscles. METHODS: Six patients with ICD underwent (18)F-FDG PET/CT. Dystonic muscles suitable for BT injection therapy were defined as those showing diffusely increased (18)F-FDG uptake. RESULTS: Hypermetabolic cervical muscles were identified in all 6 patients. In 2 patients who underwent PET/CT both in a supine position and in a sitting position during (18)F-FDG uptake, abnormal hypermetabolic muscles were observed by PET/CT only when patients were in the sitting position with their heads and necks in the adopted abnormal involuntary posture. Symptoms were significantly improved in 4 patients who underwent BT injection therapy guided by PET/CT and who were clinically monitored. CONCLUSION: (18)F-FDG PET/CT is potentially useful for identifying dystonic cervical muscles for BT therapy in patients with ICD. 相似文献