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991.
Excess parenchymal loss associated with hepatectomy is the leading risk factor/for liver failure especially in patients with impaired hepatic function. Selective portal embolization (PE) before hepatectomy is aimed to induce an atrophy of the embolized lobe to be resected, with a compensatory hypertrophy of the/counterlobe to be preserved. We performed PE followed by hepatectomy in 58 patients with hepatocellular carcinoma (HCC, n. = 44) or metastatic liver tumour (MLT, n. = 14). All the patients well tolerated PE, and hepatic functional data returned to the baseline levels within a week. The left lobe volume increased by about 10% after the right PE. Hepatectomy procedures undertaken comprised right or extended right lobectomy (n. = 39), central bisegmentectomy (n. = 3), extended segmentectomy (n. = 12), and limited resection (n. = 4). The 25 of HCC patients underwent right-sided lobectomy despite a presence of hepatic functional impairment, and the 3 of MLT patients under went right lobectomy with additional resection of the left lobe. As a whole, the operative morbidity and mortality rates were 15.5% and 1.7%, respectively (one patient died of liver failure). The 5-year over all survival rates were 46.8% in HCC patients and 38.0% in MLT patients, respectively. Preoperative PE therefore can be an ancillary procedure for patients, despite with hepatic dysfunction or with bilobar tumours, who may need extensive hepatectomy.  相似文献   
992.
A previously healthy 12-year-old Japanese girl developed meningoencephalitis due to Cryptococcus neoformans. During the course of her illness she suffered persistent high fever, severe pancytopenia, hypercytokinemia and liver dysfunction. Laboratory findings, including results of a bone marrow examination, strongly indicated complication by haemophagocytic syndrome (HPS). The preceding cryptococcal infection was thought to be a cause of the HPS because no other viral or bacterial infection could be confirmed. The girl died of acute respiratory failure during the progressive course of HPS. This may be the first reported case of HPS due to cryptococcal infection in an otherwise healthy child.  相似文献   
993.
Patients with chronic hepatitis B virus (HBV) infection have historically incurred high rates of allograft reinfection from extrahepatic reservoirs of HBV, with worse long term outcome compared with that of transplant recipients without HBV infection. As a result, chronic HBV infection has been considered a contrandication for transplantation. Prophylaxis against HBV recurrence, in the form of passive immunization with high dose hepatitis B hyperimmunoglobulin and the antiviral agent lamivudine, has recently been demonstrated to decrease the risk of reinfection. With appropriate prophylaxis, liver transplantation can be a viable proposition for patients with HBV infection. Past experience and current status of HBV infection and transplantation are reviewed, with emphasis on the issues surrounding prophylaxis.  相似文献   
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996.
We have established immortalized human granulosa cells by triple transfection of primary cells obtained from in vitro fertilization patients with SV40 DNA, Ha-ras oncogene, and a temperature sensitive (ts) mutant of the tumor suppressor gene p53 (p53val135). Forty-one clones were isolated, and their steroidogenic responses were analyzed. While all the cell lines proliferate rapidly and show only traces of progesterone production, upon stimulation with 50 microM of forskolin (FK), which elevates intracellular cAMP, they become steroidogenic as evidenced by progesterone production. The steroidogenic response of the cell lines was stable even after 20 generations and several cycles of freezing and thawing. A highly responsive cell line (HO-23) was further examined for characteristics of the steroidogenic response. Cells stimulated with FK and 8-Br-cAMP produced high levels of pregnenolone, progesterone, and 20alpha-hydroxy-4-pregnen-3-one (20alpha-OH-progesterone) comparable with amounts produced by highly differentiated primary human granulosa-luteal cells. Hydrocortisone and dexamethasone highly augment the cAMP-stimulated progesterone production, whereas testosterone and PRL enhanced cAMP-induced progesterone synthesis only moderately. Estradiol, insulin-like growth factor I, and insulin showed no significant effect on cAMP-induced steroidogenesis. The phorbol ester TPA, and basic fibroblast growth factor, dramatically suppress cAMP-induced production of progesterone, whereas bovine corneal endothelial cell ECM (BCE/ECM) enhanced cAMP-induced progesterone and antagonized basic fibroblast growth factor suppression of cAMP-induced steroidogenesis. Steroidogenic factor 1 (Ad4BP/SF-1) was expressed in control cells, and its expression was augmented by FK, whereas the steroidogenic acute regulatory protein showed low expression in the nonstimulated cells but was clearly elevated upon cAMP stimulation and was slightly decreased by TPA in cAMP-stimulated cells. Expression of the electron carrier adrenodoxin (ADX), which is a part of the cytochrome P450scc enzyme system, was very low in nonstimulated cells but was dramatically elevated in FK- and 8-Br-cAMP-stimulated cells, whereas no reduction of ADX was evident in cells costimulated with FK and TPA. Immunocytochemical studies revealed a weak staining of ADX in mitochondria of nonstimulated cells and intensive staining in highly clustered mitochondria of FK- or 8-Br-cAMP-stimulated cells. Only moderate reduction in ADX staining was evident in cells costimulated with FK and TPA. These unique cell lines can provide a useful model for the investigation of induced steroidogenesis in human granulosa cells.  相似文献   
997.
The abilities of 9 kinds of human biliary tract carcinoma cell lines to invade through basement membrane or type I collagen were examined using an in vitro invasion assay system. The correlations between invasiveness and morphologic characteristics of the carcinoma cells in 3 dimensional collagen gel were also examined. most of the biliary tract carcinoma cell lines kept the abilities of glandular differentiation and basement membrane formation of the original tumor. Their invasiveness, however, correlated with the degree of in vitro morphologic differentiation regardless of their original morphology.  相似文献   
998.
Lipoarabinomannan (LAM) is a major surface lipoglycan of Mycobacterium tuberculosis. In the present study, we demonstrated that arabinofuranosyl-terminated LAM (AraLAM) derived from a rapidly growing Mycobacterium sp., but not extensively mannosylated LAM derived from the Erdman strain, is capable of inducing interleukin-12 (IL-12) expression in murine macrophages. Since IL-12 is known to drive the differentiation of naive T cells toward T-helper type 1 (Th1) cell development, AraLAM may be an effective adjuvant in vaccines and immunotherapies that need Th1 responses.  相似文献   
999.
Otoacoustic emissions evoked by electrical stimulation of the cochlea were measured in guinea pigs. Alternating current with acoustic frequencies was delivered directly to the scala tympani and the vestibuli of the basal turn by using a constant current stimulator made in our laboratory. The amplitude of the electrically evoked otoacoustic emmisson (EEOAE), which was 21.0 dB SPL in response to 2 kHz electrical stimuli of 120 microArms, was decreased gradually with anoxia of the animal and was reduced to below the noise level by extirpation of the ossiculum. The EEOAEs rose with a delay of 100 microseconds from the beginning of the stimulus, and reached maximum amplitude within three cycles. The output of EEOAE was magnified in a linear manner as the stimulus current increased from 10 to 200 microArms. The averages and standard deviations of the EEOAE output at the stimulus level of 170 microArms in six animals were 20.5 +/- 4.1 dB SPL for 1 kHz, 23.3 +/- 4.8 dB SPL for 2 kHz, 10.5 +/- 6.0 dB SPL for 3 kHz, 17.1 +/- 4.7 dB SPL for 4 kHz, 13.6 +/- 4.4 dB for 5 kHz and 18.3 +/- 4.8 dB SPL for 6 kHz. Measurement of EEOAE, in which stable responses could be obtained with simple and easy preparation, was considered a potential procedure for assessing the electromotility of the cochlear outer hair cells in vivo.  相似文献   
1000.
We report a case of testicular tumor detected by ultrasonography during the prenatal period. Ultrasonography performed at 32 weeks of gestation showed that one testis was larger than the other. The right testis was markedly enlarged at 38 weeks of gestation. The heterogeneous echo pattern of the right testis suggested a testicular tumor. Right high orchiectomy was performed 3 months after birth. Pathological findings of the tumor were teratoma with mature and immature components according to the histological classification of testicular tumor. In Japan, this is the second case diagnosed in the prenatal period using ultrasonography.  相似文献   
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