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991.
Neuroprotective effects of bone marrow stromal cells on rat organotypic hippocampal slice culture model of cerebral ischemia 总被引:9,自引:0,他引:9
Organotypic hippocampal slice cultures prepared from newborn rats were maintained in vitro for 9 days. Cultures were then exposed to 30 min of combined oxygen-glucose deprivation (OGD). After OGD, the area covered by neurites was decreased. The dead cells of hippocampal slices in the ischemia group were 40.4% at day 3 and 41.6% at day 7 after OGD. The ultrastructure of the CA1 region of the slices was seriously damaged. While hippocampal slices were cultured in combination with bone marrow stromal cells (MSCs), the average area covered by neurites was comparatively increased. The dead cells were only 25.2% at day 3 and 27.1% at day 7 after coculture. The damage of the ultrastructure of the CA1 region in the coculture group was reduced significantly. Thus, in an in vitro model of simulated ischemia, MSCs can promote the outgrowth of neurites from hippocampal slices and alleviate cell damage. The neuroprotective effect might be mediated through diffusible neurotrophic factors secreted from MSCs. 相似文献
992.
Yoon SS Jarnagin WR Fong Y DeMatteo RP Barakat RR Blumgart LH Chi DS 《Gynecologic oncology》2003,91(2):383-388
OBJECTIVES: Patients who develop recurrent ovarian of fallopian tube carcinoma involving the liver often have disease refractory to chemotherapy and carry a poor prognosis. The impact of aggressive resection in this patient population is unclear. METHODS: From 1/1988 to 9/2001, 24 patients with recurrent ovarian or fallopian tube carcinoma who underwent complete gross resection or optimal debulking of their hepatic metastases and disease at other sites were identified from prospective databases at a single institution. RESULTS: The median age of patients was 53 years old, and the median interval between primary diagnosis and liver resection was 69 months. All patients had primary resection or cytoreduction and chemotherapy as part of their initial treatment. Subsequent hepatic resections included trisegmentectomy (2), lobectomy (2), segmentectomy (17), and wedge resection (3). Additional resection of disease outside the liver was performed in 18 patients (75%). Twenty-one patients (88%) had removal of all gross disease, and three patients (13%) had optimal tumor debulking to less than 1 cm. Eighteen patients recurred with sites of initial recurrence, including the abdomen and pelvis (14), spine/paraspinal region (2), lung (1), and liver (1). Overall median survival was 62 months after hepatic resection with a range of 6 to 94 months. Fourteen patients were alive at the time of last follow-up, and 10 had no evidence of disease. No significant prognostic factors for overall survival could be identified on univariate analysis. CONCLUSIONS: In highly selected patients with recurrent ovarian or fallopian tube carcinoma involving the liver, hepatic resection along with resection of other gross disease may lengthen survival and should be considered as a treatment option. 相似文献
993.
二甲双胍在多囊卵巢综合征促排卵治疗中的作用 总被引:34,自引:0,他引:34
目的 评估二甲双胍在多囊卵巢综合征 (PCOS)患者促排卵治疗中的作用。方法 以40例PCOS患者 (PCOS组 )为研究对象 ,其中 2 0例口服二甲双胍治疗 12周 ,治疗后 17例未孕者加用高纯度促卵泡激素 (FSH HP)治疗 1个周期 (A组 ) ,另 2 0例单用FSH HP治疗 1个周期 (B组 ) ;同时 ,以体重和月经周期均正常的 2 0例门诊患者为对照组。观察各组及A组患者口服二甲双胍前后血清FSH、黄体生成激素 (LH)、睾酮、瘦素、空腹血糖及空腹胰岛素水平 ;比较A、B两组促排卵治疗结果。结果 空腹胰岛素和瘦素水平 ,PCOS组显著高于对照组 (P <0 .0 5) ,PCOS肥胖者高于PCOS非肥胖者(P <0 .0 5) ,但PCOS非肥胖者与对照组相比 ,差异无显著性 (P >0 .0 5)。二甲双胍治疗后 ,LH、空腹胰岛素、睾酮及瘦素水平明显下降 (P <0 .0 5~ 0 .0 1)。PCOS组患者中有 3例服二甲双胍治疗期间妊娠 ,另外 3 7例行FSH HP促排卵治疗后有 7例妊娠 (A组 4例 ,B组 3例 ) ,总妊娠率为 19% ( 7 3 7) ;A组的排卵率 ( 88% ,15 17)和妊娠率 ( 2 4% ,4 17)虽高于B组 ( 70 % ,14 2 0 ;15% ,3 2 0 ) ,但差异无显著性 (P >0 .0 5)。结论 二甲双胍能降低胰岛素和瘦素水平 ,逆转PCOS患者性激素异常 ,使部分患者恢复排卵和妊娠 ,可增强PCOS患者对促性腺素的敏感 相似文献
994.
Palliative surgery for bowel obstruction in recurrent ovarian cancer:an updated series 总被引:2,自引:0,他引:2
Pothuri B Vaidya A Aghajanian C Venkatraman E Barakat RR Chi DS 《Gynecologic oncology》2003,89(2):306-313
OBJECTIVE: Intestinal obstruction is a frequent sequela of recurrent ovarian cancer. Previous series report median survivals of 3-6 months in patients undergoing surgery for obstruction due to recurrent disease. We analyze a contemporary series of patients to determine if outcomes have changed in patients undergoing palliative surgery. METHODS: We retrospectively reviewed all patients undergoing surgery for intestinal obstruction due to recurrent ovarian cancer from 1994 to 1999. RESULTS: During the study period, 68 operations were performed on 64 patients. Mean age at the time of obstruction was 57.3 years. Mean time from original diagnosis of ovarian cancer to obstruction was 2.8 years. Surgical correction (intestinal surgery performed for relief of obstruction) was attained in 57 of 68 (84%) cases. Successful palliation (the ability to tolerate a regular or low-residue diet at least 60 days postoperatively) was achieved in 71% of cases where surgical correction was possible. The rate of major surgical morbidity was 22%. There was one death from pulmonary embolus and one from peritonitis. Two other deaths occurred due to progression of disease, for an overall perioperative mortality rate of 6%. Postoperative chemotherapy was administered in 45 of 57 (79%) cases where surgical correction was possible. The median survival of the entire cohort was 8 months. If surgery resulted in successful palliation, median survival was 11.6 months, versus 3.9 months for all other patients (P <.01). CONCLUSIONS: The majority of our patients undergoing surgery had successful palliation, and were able to receive further chemotherapy. They were discharged home, and could tolerate solid food. 相似文献
995.
Chi DS Temkin SM Abu-Rustum NR Sabbatini P Jarnagin WR Blumgart LH 《Gynecologic oncology》2002,87(1):138-142
BACKGROUND: Previous studies have reported the results of hepatic resection for metastatic ovarian cancer at the time of primary cytoreductive surgery and at the time of recurrence. CASE: We present the first case of major hepatic resection performed at the time of interval cytoreduction for metastatic ovarian carcinoma. CONCLUSION: Interval debulking with hepatic resection may be a promising approach for patients left with bulky parenchymal liver metastasis after primary cytoreductive surgery. 相似文献
996.
Park JH Jung MK Bang CO Park HK Sung KB Ahn MY Bae WK Chi JG 《Journal of Korean medical science》2002,17(5):718-722
We report a rare case of neuro-Behcet's disease (NBD) presenting as an inflammatory pseudotumor in the brain. A 52-year-old woman was evaluated for subacute dizziness and headache. Brain magnetic resonance (MR) imaging showed a right cerebellar mass, which disappeared 2 weeks later. After a year, recurrent mucocutaneous manifestations of Beh et's disease were observed. Immunosuppressant and steroid maintenance treatment were started. She experienced two more neurologic attacks and brain MR imaging revealed an enhancing mass in the right temporal lobe. The second attack showed a good response to steroid pulse therapy, but the third attack did not respond to steroid and her neurologic signs suggested an impending transtentorial hernia. The right temporal lobectomy was performed for the purpose of life-saving. The pathologic finding of the mass was a chronic inflammatory vasculitis, compatible with NBD. 相似文献
997.
Complementation of a Treponema denticola flgE mutant with a novel coumermycin A1-resistant T. denticola shuttle vector system 下载免费PDF全文
By using the mutated gyrB gene from a spontaneous coumermycin A1-resistant Treponema denticola, an Escherichia coli-T. denticola shuttle vector that renders T. denticola resistant to coumermycin was constructed. The complete T. denticola flgE gene was cloned into the shuttle vector pKMCou, and the vector was transformed into the T. denticola ATCC 33520 flgE erythromycin-resistant knockout mutant HL210. The coumermycin-resistant transformants were motile and restored FlgE activity. This complementation system should prove useful in studying the virulence factors of T. denticola and uncultivatible pathogenic spirochetes. 相似文献
998.
A composite graft material containing bone particles and collagen in osteoinduction in mouse. 总被引:4,自引:0,他引:4
Chung-Hung Tsai Ming-Yung Chou Mecrehild Jonas Yung-Tico Tien Emily Y Chi 《Journal of biomedical materials research》2002,63(1):65-70
Demineralized allogenic bone matrices (DABM) and demineralized freeze-dried bone allograft (DFDBA) have been successfully used as bone-graft materials in the treatment of acquired and congenital cranio-maxillofacial defects and in some orthopedic surgery. However, these bone-graft "powders" have many shortcomings. For example, placement of particulate graft material in a hemorrhaging site can result in inadequacies or inaccurate attachment as well as loss of the graft materials. To minimize the inadequacies of powderlike graft materials, xenogenic collagen isolated from human tendon, skin, or bone was added to the bone-graft particles to form a composite spongelike implant. This material is commercially available and consists of 60% collagen and 40% DFDBA (DynaGraft, GenSci Co., Irvine, CA). The goal of this study was to evaluate the characteristics of composite graft implants in the mineralization process in an animal model in comparison with DFDBA powder and pure collagen. Seventy-two Swiss Webster mice were divided into three groups: an experimental group implanted with DynaGraft, two comparison groups implanted with either DFDBA or collagen only. All the graft materials were surgically implanted and inserted into the left thigh muscle. Mice were humanely killed at 1, 2, 3, 4, 6, 8, and 12 weeks. Then the muscle tissues in the vicinity of the implants were excised and processed for histology. Paraffin sections were stained with hematoxylin and eosin (H&E), the Von Kossa method, and Masson's trichrome. Some selected specimens were processed for transmission electron microscopic observation. After 1 week of implantation, the DynaGraft group showed calcium deposition on the collagen material and on the periphery of the DFDBA particles. Increased calcification and bone-forming cells were observed at 4-6 weeks. After 8 weeks, the implant formed a calcified nodule and only heavily mineralized connective tissue was observed at the implanted site. The group implanted with DFDBA powder showed calcification around the particulates. The collagen-sponge control group revealed no calcification or bone formation during the period of implantation. The light microscopic findings were confirmed by electron microscopy. Quantitative radiographic density DynaGraft and DFDBA graft followed sequentially over a period 120 days. It was concluded that a higher rate of calcification and bone formation was produced in the composite graft implant compared to the DFDBA implant. The composite graft material (DynaGraft), which contains both collagen and DFDBA, proved to be more effective for bone formation than particle components alone. 相似文献
999.
Chi XS Landt Y Crimmins DL Dieckgraefe BK Ladenson JH 《Journal of immunological methods》2002,266(1-2):197-207
To investigate the role of Reg Ialpha in human inflammatory bowel disease (IBD), we made two phage-displayed single chain variable fragment (scFv) libraries from rabbits immunized with recombinant or native human Reg Ialpha. After one to three rounds of panning, we were able to isolate phage-displaying scFvs, which bound to human Reg Ialpha. Anti-Reg Ialpha scFvs from both libraries showed similar immunoreactivity to different processed forms of the protein. Despite several DNA fingerprint patterns among these clones, their deduced amino acid sequences are highly homologous with 100% identity in the complementarity-determining regions (CDRs) of the variable segment of heavy chain (VH) region and a small variation in the CDR1 of the variable segment of light chain (VL) region. We also expressed and purified soluble myc-tagged or glutathione S-transferase (GST) fusion scFv proteins from bacteria. Immunohistochemical studies using one of our anti-Reg Ialpha scFv antibodies showed prominent staining in the metaplastic Paneth cell population and light staining in the lamina propria. This scFv antibody is now being used for studies of the role of Reg Ialpha in human IBD. 相似文献
1000.
Chi H Lee YJ Chiu NC Huang FY Huang CY Lee KS Shih SL Shih BF 《The Pediatric infectious disease journal》2002,21(5):384-387
BACKGROUND: Acute suppurative thyroiditis in children is rare and is often related to a pyriform sinus fistula or thyroglossal duct remnant, especially when it is recurrent. METHODS: From January, 1985, through December, 2000, 15 children with acute suppurative thyroiditis were treated. Their clinical, laboratory and radiologic findings were reviewed and analyzed. RESULTS: There were 8 girls and 7 boys, with a mean age at diagnosis of 6.1+/-2.9 years (range, 1.5 to 9.8). A thyroid mass was present on the left in 13 and on the right in 2 (P < 0.05). Fever, neck pain and swelling were the most common symptoms and signs. Seven patients (46.7%) had recurrent disease. Needle aspiration for Gram stain and bacterial cultures were done, and pathogenic organisms were identified on culture in 8 patients but were found only on Gram stain in 2 patients. In one-half of the patients with positive cultures, mixed pathogens were found. The most common organisms isolated were streptococcal species (50%). Barium esophagography was performed in all patients, and 5 (33.3%) had a pyriform sinus fistula on the left. Only 1 of the recurrent patients had a fistula. Thyroid scans were performed in 13 patients, of whom 12 (92.3%) had decreased radioactive uptake. Thyroid function tests were normal in all 15. CONCLUSIONS: Acute suppurative thyroiditis is usually caused by oropharyngeal flora, resulting in mixed pathogens on culture. Broad spectrum antibiotics should be given once cultures have been obtained. Imaging studies might be helpful in the diagnosis of acute suppurative thyroiditis. 相似文献