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21.
Summary Serum samples from eight endogamous Indian tribal populations of Madhya Pradesh (Dhurwa, Halba, Bhatra, Muria, Maria) and Orissa (Deshia Khond, Binjhal, Kisan) with a total of n=731 unrelated individuals were typed for G1M (1,2,3,17), G3M (5,10,11,13,14,15,16,21,26), and KM (1). In seven of these populations five different GM haplotypes were found:GM*1,17;21,26; GM*1,17;10,11,13,15,16; GM*1,2,17;21,26; GM*1,3;5,10,11,13,14,26; andGM*3;5,10,11,13,14,26. In the Kisan sample the haplotypeGM*1,2,17; 21,26 is absent. The intergroup variability in the distribution of these haplotypes is considerable and statistically highly significant. The reasons for that can be attributed to the ethnohistory and to the genetic isolation of these eight endogamous tribal populations. The GM haplotype distribution pattern of all these groups is quite different from that of the non-tribal populations of India, whereas it is in good agreement with that of the so far tested other tribal populations from India. This can be explained by different origin and history of the Indian tribal and non-tribal populations. In the KM system, too, remarkable variability is seen in the distribution of phenotype and allele frequencies among the eight tribal populations under study.  相似文献   
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PROBLEM: Development of an orally administered abortifacient. METHODS: Subjects were female Wistar rats, weighting 150 to 200 g at the time of experiments. Praneem (a purified extract of neem Azadirachta indica) at a dose of 0.6 ml was given orally from day 8 to 10 after confirming presence and number of implants surgically on day 7 of pregnancy. The animals were examined again under anesthesia on day 15 of pregnancy to check the number of developing embryos. Controls received an equivalent regime of peanut oil. The number and size of implants were counted five days after treatment. RESULTS: Complete resorption of embryos was observed on day 15 of pregnancy in every animal treated with Praneem in contrast to normally developing embryos in rats given peanut oil. In repeat batch experiments, it was established that the effect of the treatment was reversible and animals regained fertility in cycles subsequent to treatment with Praneem. Cytokines of TH1 type, i.e., gamma interferon and TNF, were raised on administration of Praneem, which may be the probable cause of pregnancy termination. CONCLUSIONS: Praneem on oral adminstration can cause termination of pregnancy in rodents, and the action is probably mediated by TH1 cytokines.  相似文献   
24.
Structural anomalies of mitotic chromosomes from two tumorigenic cell lines of the German cockroach (Blattella germanica) is described. Aberrations, such as unpairable marker chromosomes, double minutes, di- and tricentrics, ring chromosomes, tri- and quadriradials, and chromosome and chromatid gaps and breaks, were observed in varying proportions. This study reports that the double minute chromosomes (DMs) are associated with insect tumor cells, similar to the findings in both murine and human tumor cells.  相似文献   
25.
Oxidative phosphorylation of isolated canine myocardial mitochondria has been evaluated after exposure to different concentrations of phosphate (5--50 mM), lactate ion in excess (5--40 mM, pH 7.4), calcium (50--270 nmol/mg protein), to lactic acidosis (pH 6.3), and to mitochondrial protein dilution (in vitro volume expansion) for 10 min to 8 h. The influence of phosphate and lactate ion addition, lactic acidosis, and in vitro volume expansion on mitochondrial function were studied in the isolation medium (0.18 M KCl, 0.5% BSA (bovine serum albumin), with or without Tris-EDTA, pH 7.4) prior to evaluation of mitochondrial function in the assay medium (0.25 M sucrose, 10 mM Tris-HCl, and 10 mM inorganic phosphate, pH 7.4). The effect of calcium addition was assessed in the assay medium. The results of these studies demonstrate that each of these interventions detrimentally alters mitochondrial oxidative phosphorylative ability. The most severe mitochondrial functional impairment resulted from phosphate or calcium addition. The detrimental effect of phosphate and in vitro volume expansion was partially corrected by the addition of cytochrome c.  相似文献   
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27.
Immunoglobulin M (IgM) and IgG1 monoclonal antibody isotype switch variants to Cryptococcus neoformans capsular polysaccharide were used to study the sensitivity of a double sandwich enzyme-linked immunosorbent assay (ELISA). The most sensitive ELISA configurations used IgG1 monoclonal antibody absorbed on polystyrene plates or IgM immobilized with goat antisera for antigen capture.  相似文献   
28.
Effects of an inhibitor of membrane anion-exchange transport processes, 4-acetamido-4-isothiocyano-2,2-disulfonic stilbene (SITS), on urate transport by isolated, perfused snake (Thamnophis spp.) proximal renal tubules were studied. SITS (10–4 mol/l) in the luminal perfusate had absolutely no effect on net urate secretion (J urate net ) or on net fluid absorption (J v). This observation is compatible with other data that give no support to the concept of a mediated transport step for urate from the cells to the lumen. SITS (10–4 mol/l) in the bathing medium reversibly inhibitedJ urate net without affectingJ v. At the time of maximum inhibition ofJ urate net , the concentration of urate in the cell water was increased and the apparent permeability of the luminal membrane to urate was decreased, but the urate efflux across the peritubular membrane and the apparent permeability of the peritubular membrane to urate were unchanged. There was no evidence of significant intracellular binding or trapping of urate. Although an increase in the initial rate of urate transport into the cells across the peritubular membrane could not be demonstrated conclusively in nonperfused tubules, the results still suggest that SITS in the bathing medium may inhibitJ urate net by inhibiting urate movement from the cells to the lumen while actually enhancing transport from the bathing medium into the cells.  相似文献   
29.
A microtiter plate ELISA with semipurified human nerve sonicate antigen(s) (NA) was used to screen the sera of leprosy patients. High titers of IgG and low titers of IgM classes of antineural antibodies directed to peripheral nerve antigens were detected in LL, BL, BB, BT, and TT categories of leprosy. In the Western blot, leprosy sera recognized 50- to 55-, 85- and 108-kDa molecular weight protein bands of NA. The identity of these protein bands immunoreactive with leprosy sera was checked with a panel of commercially available antibodies to known neural proteins. The 50- to 55-kDa band reacted with anti-S100 and anti-glial fibrillary acidic protein antibodies while 85 and 108 kDa could not be identified. Whole immunoglobulins isolated from leprosy sera with high titers of antineural antibodies induced cytotoxicity of the cultured glial cell line in the presence of complement.  相似文献   
30.
D Roberts  D R Katz  S Mukherjee    G A Rook 《Immunology》1988,63(4):697-700
We describe the use of 5-hydroxytryptamine (5HT) as an adjuvant in the induction of the delayed-type hypersensitivity (DTH) response to purified protein derivative (PPD). Based upon our previous studies with antigen-pulsed macrophages (M phi), we have shown that both the Day 2 early (2 hr) reaction and the Day 3 (24 hr) reaction are augmented if 5HT is incorporated into the priming injection. Furthermore, we have confirmed that in contrast to M phi, antigen-pulsed dendritic cells (DC) fail to prime the early (2 hr) component of DTH. However, DC do prime the early response if injected along with 5HT. A peripheral 5HT antagonist, ICS 205-930, inhibits both the M phi-mediated and the 5HT/DC-primed reactions. These findings support the hypothesis that DTH reactions require a cascade of both inflammatory and immunological signals, and that in mice vascular permeability mediated via 5HT is important in the early phase of the reaction.  相似文献   
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