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71.
72.
H Yanagawa S Sone A Okubo K Fukuta Y Nishioka T Ogura 《Japanese journal of clinical oncology》1990,20(4):356-363
Interferon-gamma (IFN-gamma) acts on a large array of different types of cell and has potent immunomodulatory activities besides cytotoxic effects on tumors. In a phase I study, some immunologic parameters of blood mononuclear cells from healthy volunteers who received intramuscular injections of natural human IFN-gamma were analyzed. The percentage of Leu-11a positive cells, natural killer (NK) activity, lymphokine (interleukin-2)-activated killer (LAK) activity and monokine production were measured either in blood mononuclear cells or in purified samples of lymphocytes or monocytes of the donors before and 24 h after IFN-gamma injection. After IFN-gamma injection, the percentage of Leu-11a positive cells and the LAK activity in the blood were significantly reduced, but NK activity and monokine production remained unchanged. These findings suggest that in vivo IFN-gamma acts directly or indirectly on Leu-11a positive cells and reduces LAK activity by changing the recruitment of LAK precursors in the blood. 相似文献
73.
The relationship between physical stability of freeze-dried cakes and protein stability during storage was studied using -galactosidase as a model protein and inositol as an excipient. Amorphous samples freeze-dried from solutions containing the enzyme and various concentrations of inositol in sodium phosphate buffer (50 mM, pH 7.4) were stored for 7 days over P2O5 at 40 to 70°C. Structural collapse and inositol crystallization were observed in some of the samples, depending on the formulation and storage temperature. The physical stability of freeze-dried samples was also studied by differential scanning calorimeter (DSC). Inositol showed a protein-stabilizing effect when its amorphous form was retained during storage, regardless of structural collapse. However, crystallization of inositol during storage removed its stabilizing effect. Addition of water-soluble polymers such as dextran, Ficoll and carboxymethyl cellulose sodium salt (CMC-Na) preserved activity of the enzyme by preventing inositol crystallization. 相似文献
74.
Drs Hideo Tanaka Drs Tomohiko Hiyama Drs Hideaki Tsukuma Drs Yasuto Okubo Drs Hajime Yamano Drs Akira Kitada Drs Isaburo Fujimoto 《Cancer causes & control : CCC》1994,5(5):409-413
To clarify the demographic characteristics of the prevalence of hepatitis C virus (HCV) infection in Osaka, Japan, where hepatocellular carcinoma is common, we investigated the screening data of antibody to HCV (anti-HCV, DAINABOTHCVPHA, second generation assay) in 197,600 voluntary blood donors residing in Osaka. The study found that age-standardized prevalence of anti-HCV was significantly higher than that of HBsAg (2.25cf 0.86 percent among males,P<0.001; 2.17cf 0.55 percent among females,P<0.001. It was much higher in the blood donors aged 55–64 years than in those aged 16–54 years (8.49cf 1.32 percent among males,P<10–5; 7.26cf 1.42 percent among females,P<10–5). The prevalence of anti-HCV among males was significantly higher than that of females in the younger (25–34 years) generations (1.02 to 1.49 percentcf 0.71 to 1.13 percent,P<0.05). A similar tendency was observed in the prevalence of high-titer (212) anti-HCV. The number of coinfection (both HBsAg and anti-HCV seropositive) was very small, and it was not statistically different from the expected number. 相似文献
75.
We examined remaining solvents in dry cleaned trousers to estimate the magnitude of environmental pollution. A cleaning solvent of petroleum hydrocarbon was analyzed by means of capillary column mass spectrum gas chromatography. Principal ingredients were identified to be nonane, decane and undecane. The same main components were detected in dry cleaned trousers. Total amounts of evaporated vapor from a pair of trousers (480 g) in 5 days after dry cleaning were nonane (0.73 mg), decane (1.53 mg) and undecane (1.09 mg). The levels on the fifth day were 5%(nonane), 18%(decane) and 32%(undecane) of the first day's concentration, respectively. The half times of the remaining solvents were 1.0 day (nonane), 1.7 days (decane) and 2.7 days (undecane), respectively. 相似文献
76.
T Kokawa K Shiota K Oda S Okubo Y Okamoto H Okubo 《Gan to kagaku ryoho. Cancer & chemotherapy》1983,10(3):768-774
Immunopotentiators may mitigate the depression of immunological function caused by the cancer itself or by chemotherapeutics. However, it has been found that these immunopotentiators reduce the metabolic activity of the host against drugs, including "masked" chemotherapeutics, which might be activated by metabolization in the body. Reported here is the result of serial experiments carried out on the activation of cyclophosphamide (CPM) in tumor-bearing animals, pretreated with phenobarbital, a drug-metabolizing enzyme inducer, and coenzyme Q10, a physiological activator of the electron transfer system in mitochondrias, in combination with immunopotentiators. Female Donryu rats (120 g body weight) implanted with Yoshida Sarcoma cells (YS) (2.5 X 10(6) i.p.) were treated with CPM (160 mg/kg X 1 i.p.), 84 hrs after implantation; the levels of the normustard-like substances (active metabolites of CPM) were serially measured. Some of the animals were also treated with PSK (125 mg/kg X 5 i.p.), a proteinpolysaccharide immunopotentiator obtained from mycelia of the Coriolus vesicolor, or with OK-432 (10 KE/kg X 5 i.m.), a streptococcal immunopotentiator. The results obtained were as follows: The blood levels of the normustard-like substances were lowered, i.e. the CPM activation was depressed in the YS-bearing rats and the depression was markedly intensified by PSK or OK-432 administration. Phenobarbital (40 mg/kg X 3 i.p.) or coenzyme Q10 (5 mg/rat X 5 i.p.) administration could mitigate the depression of the blood levels caused by the immunopotentiators, and the combination of phenobarbital with coenzyme Q10 could recover the blood levels up to those of the YS-bearing control rats, or even higher. YS-implanted (i.p.) rats treated with CPM+ immunopotentiators+coenzyme Q10 survived longer than those treated with CPM+immunopotentiators. These findings suggest the usefulness of coenzyme Q10 for the enhancement of cancer immunochemotherapy using masked compounds combined with immunopotentiators; all the more so, because coenzyme Q10 has also an immuno-stimulating effect, moreover, it presents almost no side effects in clinical application. 相似文献
77.
78.
Autogenous vascularized and nonvascularized total joint transfers were studied in the hands of Macaca fascicularis monkeys. Nine second toe proximal interphalangeal joints were transferred as a vascularized free graft to the hand, and the excised finger joints were transferred to the foot as a nonvascularized free graft. The grafts were examined clinically and histopathologically at 16 weeks to 10 months. Two of the nonvascularized free grafts were amputated because of infection and necrosis. Three had chronic infections. The four surviving nonvascularized grafts demonstrated necrosis of the hyaline cartilage and degenerative changes. Of the nine vascularized joints, one developed a wound infection that required amputation, another failed at 2 weeks because of wound dehiscence, and the remaining seven survived with preservation of the hyaline articular surfaces. The experimental technique was designed to be easily applied to clinical use. A skin island is provided as a "patency/viability monitor." The extensor mechanism is included in the graft for early function. 相似文献
79.
CONTEXT: Pregnant women are exempted from the current seatbelt legislation in Japan despite the fact that seatbelt use is essential to reduce the risk of fatalities for these women and their fetuses in car crashes. OBJECTIVE: To examine factors that might influence seatbelt use during pregnancy. METHODS: A cross sectional study, with data collected via an anonymous, self administered questionnaire at obstetric clinics in suburban areas of Japan. Altogether 880 pregnant women receiving prenatal care in July 2001 were recruited. The relative effects of factors that might influence seatbelt use during pregnancy were estimated using logistic regression analysis. RESULTS: Almost 70%-80% of pregnant women were consistent seatbelt wearers before pregnancy but seatbelt compliance was reduced by about half at 20 weeks or more gestation. Only 20% had received information on maternal seatbelt use, with one third reporting that seatbelt use is beneficial during pregnancy. Those who perceived that maternal seatbelt use is beneficial tended to maintain use, but daily car users and those who knew that they were exempted from seatbelt legislation were more likely to reduce use. CONCLUSIONS: Knowledge of the legislative exemption for pregnant women, misunderstanding of the benefits, and daily car use contributed to the reduction in seatbelt use after pregnancy. 相似文献
80.
Ken-ichi Ueno Hiroko Togashi Mitsuhiro Yoshioka 《Nihon shinkei seishin yakurigaku zasshi》2003,23(1):47-55
The present study was undertaken to evaluate juvenile stroke-prone spontaneously hypertensive rats (SHRSP) as an animal model of attention-deficit/hyperactivity disorder (AD/HD). Juvenile SHRSP showed significant increases in horizontal ambulatory activity and vertical rearing activity in the open field as compared with genetic control Wistar-Kyoto rats (WKY). Anxiety-related behavior assessed by elevated plus-maze as an index of impulsivity, the entries into open arms and the spent time in the open arms of SHRSP were significantly higher than those of WKY. Spontaneous alternation behavior requiring attention and working memory in the Y-maze was significantly impaired in male, but not female, SHRSP when compared with sex-matched WKY. Hippocampal long-term potentiation formation, a cellular model of learning and memory, was not impaired in SHRSP. Methylphenidate, a first choice psychostimulant for AD/HD, significantly alleviated the hyperactivity in SHRSP. However, intense impulsivity of SHRSP was not improved by methylphenidate. Methylphenidate dose-dependently and significantly ameliorated the impaired spontaneous alteration behavior in male SHRSP. These results suggest that juvenile male SHRSP manifest problematic behavior resembling ADHD, namely inattention, hyperactivity and impulsivity. Methylphenidate alleviates the behavioral symptoms of hyperactivity and inattention. Thus, juvenile male SHRSP might be a useful behavioral animal model of AD/HD, from behavioral and pharmacological perspectives. 相似文献