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991.
紫香驱蚴灵是预防日本血吸虫尾蚴感染的新型皮肤外用药。经毒性试验研究证实,大鼠口服LD50为2636(2207—3148)mg/kg,皮肤给药的LD50>5325mg/kg。家兔皮肤敷药部位未见红斑和水肿,豚鼠皮肤过敏试验,未见过敏反应,表明紫香驱蚴灵属低毒类、无刺激性、弱致敏性物质,局部皮肤外用是较安全的  相似文献   
992.
Effects of estradiol and testosterone and of the antiandrogens cyproterone acetate, niftolide, and antiestrogen tamoxifen on the activities of human erythrocyte glutathione peroxidase and glutathione reductase were studiedin vitro. In contrast to hormone preperations, antihormones in high concentrations (10−4−5×10−4 M) modified the enzyme activities. Cyproterone acetate and tamoxifen increased the activity of glutathione reductase, while tamoxifen stimulated glutathione reductase and inhibited glutathione peroxidase. Niftolide inhibited both enzymes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 8, pp. 185–187, August, 1997  相似文献   
993.
Antibody against fusarochromanone (TDP‐1) was obtained from rabbits after immunization with TDP‐1 conjugated to bovine serum albumin (BSA). An indirect enzyme‐linked immunosorbent assay (ELISA) using TDP‐1‐ovalbumin conjugate as the antigen coated on to the microtiter plate was used for monitoring the antibody liter. For toxin detection, a direct competitive ELISA in which TDP‐1 was conjugated to horseradish peroxidase (HRP) was used. Competitive direct ELISA revealed that the antibody had about 5.6 and 4.5 times greater binding efficiency for monoacetyl fusarochromanone (TDP‐2) and diacetylated TDP‐1 than TDP‐1. The concentration causing 50% inhibition of binding of TDP‐1‐HRP to the antibody by TDP‐1, TDP‐2 and diacetyl‐TDP‐1 were 2.8, 0.5 and 0.62 ng/ml, respectively. For the analysis of fusarochromanones in wheat and barley, the toxins were first extracted from the commodities with 100% methanol. A small aliquot of the extract was dried, acetylated, diluted in buffer and then analyzed directly by ELISA. The overall recovery for fusarochromanone in the wheat and barley samples spiked with TDP‐1 in the concentration range of 20 to 500 ppb were found to be 97% and 103.4% with cv of 15% and 11.2% for barley and wheat, respectively.  相似文献   
994.
Ruthenium red has been shown to have a positive inotropic effect on isolated perfused hearts. The cellular mechanism of this action is not clear. Ruthenium red is able to block the Ca2+ release channel in isolated sarcoplasmic reticulum (SR) vesicle and reconstituted channel preparations. However, the effect of ruthenium red on SR Ca2+ release has not been studied in skinned cardiac muscle preparations. In the present study we investigated the actions of ruthenium red on both the characteristics of force generation by the contractile apparatus and Ca2+ release from the SR in chemically skinned rat papillary muscle. Ruthenium red (2 and 10 M) significantly increased the Ca2+ sensitivity of the contractile apparatus (decreasing Ca2+ required for the half-maximal response from 1.56±0.04 M to 1.46±0.05 M) but had no effect on the maximal Ca2+-activated force in triton X-100 treated fibers. This result may suggest one explanation for the positive inotropic effect of ruthenium red on the heart. On the other hand, ruthenium red had no significant effect on either caffeine-induced Ca2+ release or Ca2+-induced Ca2+ release from the SR in saponin-skinned muscle fibers. Lack of a blocking effect on SR Ca2+ release by ruthenium red in skinned fibers suggests that the SR Ca2+ channels in intact preparations have characteristics that are different from those of either vesicular or reconstituted channel preparations.  相似文献   
995.
996.
A histological and histochemical study was made of the internal organs of albino mice at various times (from 24 h to 27 weeks) after a single intraperitoneal injection of L-forms of -hemolytic group A streptococci. A progressive pathological process (myocarditis, hepatitis, glomerulonephritis) against a marked allergic bacground and leading to systemic lesions of the tissues was discovered.Institute of Human Morphology, Academy of Medical Sciences of the USSR. N. F. Gamaleya Institute of Epidemiology and Microbiology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. P. Avtsyn.) Translated from Byullten' Éksperimental'noi Biologii i Meditsiny, Vol. 80, No. 9, pp. 111–115, September, 1975.  相似文献   
997.
An autopsy-proved case of AIDS in Taiwan   总被引:1,自引:0,他引:1  
The first case of AIDS positively identified in a non-foreigner in Taiwan was a 25-year-old unmarried male who had practiced homosexuality for ten years. The patient began to have abdominal pain accompanied with loose stools and weight loss in June 1985, followed by fever, cough, headache, dizziness, and loss of memory. Facial hyperpigmentation and extensive oroesophageal candidiasis were noted. Laboratory studies showed severe lymphopenia with a reversed T-helper to T-suppressor ratio, cutaneous anergy and polyclonal gammopathy. Human immunodeficiency virus (HIV) antibodies were positive by ELISA and Western blot, and the virus was isolated from the blood. At autopsy, disseminated cytomegalovirus infection, extensive CNS toxoplasmosis and early lesions of Kaposi's sarcoma were demonstrated. The detection of HIV in the adrenal medulla supports the consensus that the virus is neurotropic.  相似文献   
998.
氧分压在体监测仪的研制   总被引:2,自引:0,他引:2  
作者报道一种稳定性较高的氧分压在体监测,为医学研究、临床诊断提供一种新的可靠的测试方法及设备,具有较大的应用价值。  相似文献   
999.
The immunodepressive effect of cyclophosphamide (CP) was studied on mice of three strains (BALB/c, CBA, DBA/2) immunized with sheep's red cells (RBC). When the optimal immunizing dose of antigen was used (5×108 RBC) the strongest immunodepression was observed in the DBA/2 mice, but when a large dose of RBC was used (6.2×109) the strongest effect was observed in DBA/2 and CBA mice. The action of CP was shown to depend on the dose of antigen injected: In BALB/c mice the decrease in the number of antibody-forming cells was the same with both doses of RBC, in the DBA/2 mice an increase in the dose of antigen led to weakening of immunodepression, but in CBA mice immunodepression was intensified (provided that sufficiently large doses of CP were used). Determination of the rate of oxidative hydroxylation of CP by the mouse liver microsomes showed it to be comparatively low in DBA/2 and CBA mice and much higher in BALB/c mice. It is suggested that the differences in the immunodepressive action of CP thus revealed could be due to differences in the sensitivity of the target cells and (or) differences in its metabolism in mice of different strains.Laboratory of Immunogenetics, Institute of Medical Genetics, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR, N. N. Zhakov-Verezhnikov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 83, No. 4, pp. 438–440, April, 1977.  相似文献   
1000.
All-Union Oncologic Scientific Center, Academy of Medical Sciences of the USSR. Institute of Virology, Academy of Medical Sciences of the USSR, Moscow. Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 106, No. 10, pp. 471–472, October, 1988.  相似文献   
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