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991.
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
992.
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
993.
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
994.
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
995.
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
996.
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
997.
998.
Fast spiking (FS), GABAergic neurons of the reticular thalamic nucleus (RTN) are capable of firing high-frequency trains of brief action potentials, with little adaptation. Studies in recombinant systems have shown that high-voltage-activated K(+) channels containing the Kv3.1 and/or Kv3.2 subunits display biophysical properties that may contribute to the FS phenotype. Given that RTN expresses high levels of Kv3.1, with little or no Kv3.2, we tested whether this subunit was required for the fast action potential repolarization mechanism essential to the FS phenotype. Single- and multiple-action potentials were recorded using whole-cell current clamp in RTN neurons from brain slices of wild-type and Kv3.1-deficient mice. At 23 degrees C, action potentials recorded from homozygous Kv3.1 deficient mice (Kv3.1(-/-)) compared with their wild-type (Kv3.1(+/+)) counterparts had reduced amplitudes (-6%) and fast after-hyperpolarizations (-16%). At 34 degrees C, action potentials in Kv3.1(-/-) mice had increased duration (21%) due to a reduced rate of repolarization (-30%) when compared with wild-type controls. Action potential trains in Kv3.1(-/-) were associated with a significantly greater spike decrement and broadening and a diminished firing frequency versus injected current relationship (F/I) at 34 degrees C. There was no change in either spike count or maximum instantaneous frequency during low-threshold Ca(2+) bursts in Kv3.1(-/-) RTN neurons at either temperature tested. Our findings show that Kv3.1 is not solely responsible for fast spikes or high-frequency firing in RTN neurons. This suggests genetic redundancy in the system, possibly in the form of other Kv3 members, which may suffice to maintain the FS phenotype in RTN neurons in the absence of Kv3.1. 相似文献
999.
Lui VC Samy ET Sham MH Mulligan LM Tam PK 《Laboratory investigation; a journal of technical methods and pathology》2002,82(6):703-712
Hirschsprung's disease (HSCR), a congenital disease, is characterized by the absence of ganglion cells in the ganglion plexuses of the caudal most gut. In the aganglionic colon, the plexus remnants are replaced by aggregates of glial cells and hypertrophied nerve fibers. Signaling of glial cell line-derived neurotrophic factor (GDNF)-GFRAs-receptor tyrosine kinase (RET) is crucial for the development and maintenance of ganglion cells. Mutations of genes such as GDNF and RET lead to the perturbation of this signaling pathway, which causes HSCR. To understand the role of GFRAs in ganglion cells and the pathogenesis of HSCR, we intended to determine the specific cell lineages in the enteric nervous system that normally express GFRAs but are affected in HSCR. We studied colon biopsy specimens from 13 patients with HSCR (aged 1 day to 38 months) and 6 age-matched patients without HSCR as normal controls. RT-PCR, in situ hybridization, and immunohistochemistry were performed to examine the expression and cellular distributions of GFRAs in resected bowel segments of normal infants and those with HSCR. In normal infants and normoganglionic colon of patients with HSCR, the expression of GFRA1 was restricted to the glial cells and neurones of the ganglion plexuses. GFRAs expression was found to be markedly reduced in the aganglionic colons of 3 infants with HSCR but was unaffected in the aganglionic colons of 10 other infants with HSCR. Residual GFRA expression was restricted to enteric glial cells in the plexus remnants of the aganglionic colons. Hypertrophied nerve fibers were not found to express GFRA1. We provide the first evidence that abnormal expression of GFRAs in the enteric nervous system may be involved in the pathogenesis of HSCR in a subpopulation of patients. 相似文献
1000.
AIM: We tried to evaluate the role of anorectal functional diagnostic tools according to the judgement of German coloproctologists. METHOD: Questionnaires concerning accuracy of different diagnostic tests were sent to 585 physicians specialized in coloproctology. RESULTS: 261 (44.6 %) completed forms were returned. An analysis of the answers revealed that endorectal sonography is widely (73 %) regarded as useful and reliable diagnostic tool. Though manometry is still frequently used, only 50.5 % of the coloproctologists made their decision concerning the further treatment depending on the results of this method. Other radiologic methods as defecography and colon transit time are still regularly performed, though video-defecography is not accepted by most coloproctologists. Neurological investigations as pudendal nerve terminal latency, surface-EMG and needle-EMG are exclusively applied in specialized departments. DISCUSSION: Regarding the variety of diagnostic tools and its different appraisal a consensus should be defined. The usefulness of neurological examination techniques needs to be clarified before their performance can be recommended for a wide-spread routine work up. 相似文献