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31.
One of the merits of recently introduced exoscopes, including ORBEYE, is that they are superior to a conventional microscope in terms of ergonomic features. Taking advantage of it, the retrosigmoid approach can be performed in the supine position using ORBEYE. We report a consecutive series of 14 operations through the retrosigmoid approach in the supine position using ORBEYE. Fourteen consecutive patients who underwent surgery through the retrosigmoid approach for cerebellopontine (CP) angle lesions in the supine position using ORBEYE were targeted, and surgical outcomes and complications were examined. We evaluated the posture of the operator and the surgical field during this approach compared with those using a conventional microscope. In all 14 cases, all operative procedures were accomplished only using the ORBEYE. There were no operative complications due to this approach. Using ORBEYE, even when the angle of the operative visual axis was horizontal, the operators could manipulate in a comfortable posture. They were not forced to be in an uncomfortable posture that extended their arms, as is often the case with a conventional microscope. Therefore, they could use shorter surgical instruments. As the cerebellum shifted downward with gravity even using slight retraction during this approach, the working space of the surgical field was easily secured. Through this approach, the operators can perform stable microsurgery of CP angle lesions in a comfortable posture. This approach can reduce the burden on the operator and the patient, leading to a refined surgical procedure.  相似文献   
32.
Clinical and Experimental Nephrology - The progression of chronic kidney disease (CKD) depends on the extent of fibrosis in the kidneys; however, a renal biopsy is necessary to evaluate the...  相似文献   
33.
The present study was designed to determine potential associations between the brain damage induced by hypoxic-ischemic (HI) insult and spatial learning impairment in an eight-arm radial maze task. We first determined the pathological outcomes after 2, 5, 9, and 17 weeks of recovery following the HI insult. The results show that the brain damage progressed from 2 up to 17 weeks of recovery. To clarify the time course of the brain damage changes, we investigated the histological changes of the same individual with magnetic resonance imaging (MRI) after 5, 9, and 57 weeks of recovery following the HI insult. The MRI changes were similar to the histological changes, and the brain damages were exacerbated in the contralateral hemisphere after 57 weeks of recovery following the HI insult. To investigate whether alteration in brain function was correlated with MRI and histological changes, the rats were made to find their way through an eight-arm radial maze was performed at either 7th or 16th weeks of recovery. According to the results, the spatial learning impairments of rats in the maze starting at 16 weeks of recovery were more severe than those at 7 weeks of recovery, indicating that the impairments were progressive and depended on the degree of brain damage. The results of the present study are the first demonstration that the evolutional and specific brain damage following the HI insult is slowly and progressively exacerbated to the contralateral hemisphere and rats who experience the HI are at risk for showing a late impairment of brain function.  相似文献   
34.
We have previously reported that in bovine adrenal chromaffin cells Ptychodiscus brevis toxin-3 (PbTx-3) does not alter the veratridine-induced 22Na influx when given alone, but increases the influx of 22Na when co-applied with either - or -scorpion venom (Wada et al. 1992). In the present study, we characterized [3H]PbTx-3 binding in bovine adrenal chromaffin cells. [3H]PbTx-3 binding was saturable, reversible and of high-affinity with an equilibrium dissociation constant (Kd) of 32.0±4.9 nmol/1 and a maximum binding capacity Bmax of 6.2 ± 1.2 pmol/4 × 106 cells (4.5 ± 0.9 pmol/mg cell protein). A Hill plot revealed the lack of cooperative interaction among the binding sites. Unlabelled PbTx-3 inhibited [3H]PbTx-3 binding with an IC50 of 31 nmol/l. However, tetrodotoxin, veratridine, - and -scorpion venom, or veratridine in combination with either - or -scorpion venom did not alter [3H]PbTx-3 binding. All these results suggest that PbTx-3 binds to a site (site 5) distinct from the previously known four toxin binding sites, which does not gate voltage-dependent Na channels by itself, but is specifically involved in the allosteric modulation of Na channels in adrenal medullary cells. Correspondence to: A. Wada at the above address  相似文献   
35.
To assess the feasibility and efficacy of rhGM-CSF in ameliorating chemotherapy-induced leukopenia in patients with advanced non-small-cell lung cancer, we conducted a double-blind placebo controlled phase III study in a multicenter setting. Patients were eligible if they had cytologically or histologically proven cancer, no prior chemotherapy, stage IIIB or IV disease, an Eastern Cooperativve Oncology Group (ECOG) performance status of 0–2, an age of less than 76 years, and no symptomatic brain metastasis, disseminated bone metastasis, or previous vertebral/pelvic irradiation. The chemotherapy regimen consisted of mitomycin given at 8 mg/m2 on day 1, cisplatin given at 100 mg/m2 on day 1, and vindesine given at 3 mg/m2 i.v. on days 1 and 8 (MVP). If the granulocyte nadir count recorded after the first cycle of MVP was less than 1,000/mm3, patients were randomly assigned to receive recombinant human granulocyte-macrophage colonystimulating factor (rhGM-CSF) or placebo during the second cycle of MVP. The dose of rhGM-CSF was 125 g/m2 given daily s.c. for 14 consecutive days starting on day 2. Of the 52 patients enrolled, 45 were evaluable. The nadir of granulocytes was significantly lower in the placebo group (P=0.007). The period during which the granulocyte count was less than 1,000/mm3 was significantly longer in the placebo group (median, 6 vs 10 days;P=0.04). The incidence of adverse effects related to rhGM-CSF, such as fever (38°C) and skin rash, was significantly higher in the rhGM-CSF group (P=0.011). The rate of response to chemotherapy did not significantly differ between the two groups. In conclusion, rhGM-CSF reduced the duration of chemotherapy-induced granulocytopenia. The clinical usefulness of this agent may be deminished because of the adverse effects encountered when it is used in combination with a moderately myelotoxic chemotherapy regimen.Institutions of the BI 71.018 Cooperative Study Group, National Cancer Center Research Institute (N. Saijo, Chairman): Douai Memorial Hospital (Y. Sano), Kanagawa Prefectural Cancer Center (K. Noda), Kantou Teishin Hospital (T. Uzawa), National Medical Center (J. Kabe), Shizuoka Prefectural General Hospital (H. Etou), Teikyo University (K. Mano), Tochigi Prefectural Cancer Center (Y. Saito), Tokyo Geriatric Medical Center (A. Kida), Tokyo Teishin Hospital (T. Morinari), Tokyo Metropolitan Komagome Hospital (S. Kudo), Tokyo Metropolitan Hiroo Hospital (A. Fujikawa), Toranomon Hospital (K. Nakada), Yokohama Municipal Hospital (K. Watanabe), National Cancer Center Central Hospital (K. Eguchi)  相似文献   
36.
Bropirimine [2-amino-5-bromo-6-phenyl-4-(3H)-pyrimidinone] is a low-molecular-weight compound that acts as an inducer of interferon in several animal species. Experiments were designed to explore the possibility of using this drug for the treatment of renal-cell carcinoma (RCC). Euthymic BALB/c mice were inoculated with murine RCC (Renca) cells and given graded doses of Bropirimine p.o. for 5 consecutive days beginning on day 1 following tumor inoculation. These mice were killed and tumors were excised on day 21. Bropirimine significantly (P<0.01) inhibited the tumor growth at a daily dose of 1,000 or 2,000 mg/kg. No adverse effect or toxicity was noted at 1,000 mg/kg, and at 2,000 mg/kg there was only a marginal body-weight reduction without any other appreciable side effect. In addition to the inhibition of tumor growth, there was a small yet significant (P<0.05) increase in the duration of survival (in days) in the Bropirimine-treated animals. When the treatment was delayed to begin on day 6 following tumor inoculation, Bropirimine did not suppress tumor growth in euthymic mice, pointing to the importance of the timing of the treatment. In athymic nude BALB/c mice lacking T-cells or T-cell function, Bropirimine also inhibited tumor growth (P<0.01). The antitumor effect of this drug was abolished by pretreatment with anti-asialo GM1 serum, which eliminated natural killer (NK) activity in euthymic mice. In vivo treatment with Bropirimine augmented the cytotoxicity of lymphocytes isolated from the spleens or lungs of the tumor-bearing mice, which were active against Renca and YAC-1 cells in vitro. This activity was NK-cell-dependent as judged on the basis of the results of the in vitro complement-dependent cytotoxicity assay. Since Bropirimine induced interferon (IFN)-/ production, significantly (P<0.05) elevating its serum concentration, and since this drug mimics the effects of IFN-/, it seemed likely that the Bropirimine-induced NK cell augmentation we found was mediated by IFN-/. These results suggest that Bropirimine, a booster of NK activity, may have potential as an adjunct to other therapeutic modalities in the treatment of human RCC.  相似文献   
37.
Liver regeneration in a patient with fulminant hepatic failure (FHF) who underwent living-related partial liver transplantation (LRLT) was investigated regarding hepatic growth factors. The patient was a 16-yr-old Japanese male who developed severe subacute FHF. LRLT was performed using an extended left lobe of the ABO matched patient's mother. In the recipient, the pre-transplant levels of both plasma hepatocyte growth factor (HGF) and transforming growth factor (TGF)-beta were extremely high and rapidly decreased following the liver replacement. The liver volume evaluated using a CAT scan increased 195% after 2 wk in graft liver and 110% after 2 wk in the hepatectomized donor. The explanted liver (FHF liver), the liver from donor (normal liver), and the graft liver [the 3rd post-transplant day (POD 3)] were all investigated immunohistochemically. FHF liver: No liver regeneration was observed [proliferative cell nuclear antigen (PCNA) labeling index (L.I.): 0%]. In the liver, both HGF in the hepatocytes and c-met on the membrane of the hepatocytes were positive. TGF-beta was positive in the hepatocytes and no apoptosis was detected by the TUNEL method. Donor liver (POD 0): Few PCNA stained hepatocytes were detected. No HGF was detected but c-met was clearly detected on the cell membrane of the hepatocytes. Neither TGF-beta nor apoptosis was detected. Graft liver (POD 3): The PCNA L.I. was conspicuous at 40%. HGF was positive in non-parenchymal cells and c-met was positive in the cytoplasm of the hepatocytes. TGF-beta was negative while apoptosis was positive in the zone 3 hepatocytes. In conclusion, these findings suggested that the liver of the patient with FHF did not respond to liver regenerative stimulus, in part, through involvement of inhibitor TGF-beta. On POD 3, the transplanted graft was in a vigorous regenerative status in comparison to that in the hepatectomized donor. The HGF/c-met system is thought to be involved in the mechanism of regeneration. Intrahepatic apoptosis was detected in the graft on the 3rd post-transplant day probably due to transient ischemia in the liver, which was not related to the Fas/Fas-ligand system.  相似文献   
38.
The levels of interleukin-12 (IL-12) (p70 heterodimer), total IL-12 (p70 heterodimer plus p40 chains), interferon-gamma (IFN-gamma) as Th1 cytokine, and those of interleukin-4 (IL-4) and interleukin-10 (IL-10) as Th2 cytokines in sera and cerebrospinal fluid (CSF) from 22 patients with human T lymphotropic virus type I (HTLV-I)-associated myelopathy (HAM) were compared with those of 22 patients with other neurological diseases (OND), including nine anti-HTLV-I-seropositive carriers. Both serum IL-12 (total and p70 heterodimer) and CSF IFN-gamma, measured by the enzyme-linked immunosorbent assay (ELISA), were significantly elevated in patients with HAM as compared to the patients with OND, including the anti-HTLV-I-seropositive carriers. Serum IFN-gamma also was significantly elevated in the HAM patients as compared to the controls. There was no significant difference in the CSF levels of IL-12 (total and p70 heterodimer) between the HAM patients and controls, whereas, for the Th2 cytokines IL-4 was detected in the CSF of four anti-HTLV-I-seropositive carriers of the 13 control patients but not in any of the patients with HAM. No significant difference was found in the serum levels of IL-4 and IL-10, nor in the CSF levels of IL-10 in the patients with HAM and in the controls. These findings indicate that in patients with HAM, the immunological balance of helper T lymphocytes between Th1 and Th2 is toward Th1 in the periphery and that Th1-mediated immunological status in the central nervous system is involved in the pathogenesis of HAM.  相似文献   
39.
The authors present a case of a "coup de sabre"--a linear form of scleroderma--in an 18-year-old woman treated by means of an expanded forehead and scalp flap, a hydroxyapatite implant, and an autologous iliac bone graft. Hydroxyapatite was implanted to augment a depressive bony deformity. The nasal deformity was repaired with an expanded forehead flap and an autologous iliac bone graft. This is the first reported case in which a deformity of scleroderma was treated with a combination of an expanded skin flap and a hydroxyapatite implant.  相似文献   
40.
Perinatal transmission of hepatitis B virus (HBV) is a common cause of chronic infection. In the present study, we evaluated the long-term efficacy of immunization against HBV in infants at high-risk, by using polymerase chain reaction (PCR). Two hundred and fifty-one infants received hepatitis B immunoglobulin at birth and a course of hepatitis B vaccine within 6 months of age between 1981 and 1993. Of 251 infants, 203 (81%) and 97 (39%) were followed until 1 and 4-6 years of age, respectively. HBV-DNA was detected by PCR in 74 (36%) of 203 children at 1 year of age, while the prevalence rate of children positive for HBV-DNA decreased to 14 (14%) of 97 children at 4-6 years of age, including 2 children who had the breakthrough variants of HBV. Our results indicate that most of HBV infections occur early, during the first year, and that immunization against HBV effectively protects infants at high-risk against viral transmission, at least up to 4-6 years of age.  相似文献   
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