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1.
We previously reported that c-kit+ stem cells which give rise to extrathymic T cells are present in the liver of adult mice. Further characterization of extrathymic T cells in the liver of adult mice is conducted here. When mice with a liver shield were lethally (9.5 Gy) irradiated, all mice survived. All tested organs showed a distribution pattern of hepatic lymphocytes on day 7. The distribution pattern in the liver was characterized by an abundance of NK (CD3? IL-2Rβ+) and extrathymic T cells (CD3int IL-2Rβ+) before and after irradiation. To determine their function, post-irradiation allogeneic bone marrow transplantation (BMT) was performed in mice with or without a liver shield. Allogeneic BM cells were rejected in mice with a liver shield and specific activation of CD8+ CD3int IL-2Rβ+ cells was induced. At that time, potent cytotoxicity of liver mononuclear cells (MNC) against allogeneic thymocytes was induced. Both NK1.1+ and NK1.1? subsets of CD3int cells expanded in these mice. An in vivo elimination experiment of the subsets indicated that the NK1.1+ subset of CD3int cells (i.e. NK T cells) was much more associated with the rejection of allogeneic BM cells. However, even after the elimination of NK T cells, allogeneic BM cells were rejected. In this case, granulocytes expanded in parallel with NK1.1? subsets. Granulocytes may also be associated with the rejection of allogeneic BM cells. These results suggest that the liver is an important haematopoietic organ even in adult life.  相似文献   
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Permeability-glycoprotein (Pgp) positive cells are known to be encoded by the multidrug-resistance gene (MDR1), and characterized by a reduced ability to accumulate drugs. The vinblastin-resistant, Pgp positive CEM-VLB 1000 and its wild type (Pgp-negative and vinblastin-sensitive) counterpart CEM-T4 human leukemia cells, when treated with the alkaloid sanguinarine, were both found to undergo apoptosis at concentrations of 1.5 microg/ml and oncosis/blister cell death (BCD) at concentrations of 12.5 microg/ml. The aim of this study was to assess the ability of sanguinarine to overcome Pgp-mediated multidrug-resistance (MDR), and also to characterize the cell death processes of apoptosis and oncosis (or bimodal cell death) induced by sanguinarine in MDR cells. The cell death processes of apoptosis and oncosis in CEM-VLB 1000 and CEM-T4 cell lines were found to be qualitatively similar when assessed by light microscopy, terminal deoxynucleotidyl transferase (TdT) end-labeling, annexin-V-binding, trypan blue exclusion and western blot analysis. Western blotting revealed an increase in the Bax/Bcl-2 ratio and activation of caspase-3 in apoptosis but not oncosis in both cell lines. The Pgp-positive CEM-VLB 1000 cells and their wild type CEM-T4 cells were both equally sensitive to sanguinarine. Thus, sanguinarine may overcome the phenomenon of Pgp-mediated MDR by inducing apoptosis through increasing the Bax/Bcl-2 ratio and activating caspase-3, and oncosis, which involved neither.  相似文献   
3.
A mathematical expression was derived to estimate the relative malaria transmission efficiency of an anopheline species with respect to a standard well-characterized species for which all vector parameters can be sufficiently determined. The method is particularly useful in situations where multiple anopheline species contribute to human malaria transmission and requires the estimation of the man-biting rate, the sporozoite rate, and the human malaria incidence. Under stable conditions of vector abundance, the average sporozoite rate in a species during a transmission season would by itself reflect its relative transmission efficiency. This "efficiency" then was used to calculate the "effective human-biting rate"; i.e., the human-biting rate of that species if it were to have ecological properties identical to those of the standard species. The standard well-characterized species then could be used with the effective human-biting rate of all species to quantify transmission, thus overcoming the need to measure vector parameters for all anopheline species contributing to transmission. An expression also was derived to calculate the relative contribution made by each species to malaria transmission. The usefulness of this method was illustrated using entomological and epidemiological data from Kataragama, Sri Lanka.  相似文献   
4.
The authors have studied the ability of glial cell line-derived neurotrophic factor (GDNF) to promote survival of human fetal dopaminergic tissue after a storage period of 6 days and subsequent implantation into the human putamen. The results indicate that GDNF promotes survival of stored dopaminergic cells. Cells stored without GDNF had a 30.1% decrease in survival time compared with those exposed to GDNF. Two patients with Parkinson's disease received bilateral putaminal implants of fetal dopaminergic cells exposed to GDNF for 6 days and showed enhancement of graft survival as assessed by positron emission tomography scanning. A mean increase of 107% in putaminal fluorodopa uptake from baseline values was observed 12 months postgrafting.  相似文献   
5.
Hump-nosed pit viper (Genus Hypnale) is a medically important venomous snake in Sri Lanka and Southwestern India which causes significant morbidity and mortality. Envenoming of this snake results in hemostastic dysfunction, thrombotic microangiopathy, acute kidney injury and death. This case describes an authenticated first case of ischemic stroke in a 65?year old male following envenoming by H.hypnale in Sri Lanka.  相似文献   
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Effect of maternal fasting on uterine arterial blood flow   总被引:1,自引:0,他引:1  
AIM: To determine the effect maternal diet pattern on the uterine artery Doppler flow velocimetry. METHODS: This is a cross-sectional observational study. The uterine artery Doppler flow velocimetry was measured between 20 and 24 weeks' gestation in healthy pregnant women observing Ramadan. For each fasting mother, a non-fasting healthy pregnant woman was recruited as a control. Maternal blood glucose level was measured. RESULTS: A total of 106 pregnant women were studied. The mean hours since last oral intake were significantly longer, and the maternal glucose level was significantly lower in the study group than in the control group. The Mean (95% CI) of the uterine artery pulsatility index, resistance index, peak systolic velocity, end diastolic velocity and systolic/diastolic ratio was similar in both groups. CONCLUSION: Maternal fasting is not associated with significant changes in the uterine artery Doppler flow velocimetry.  相似文献   
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This study examines the effect of household wealth on marital fertility in Sri Lanka. Data on type of dwelling, availability of vehicles, and electrical equipment in households were combined with estimates of 'typical' rupee values of various elements to generate an index of their wealth. Differentials in value of the wealth indices among sociodemographic subgroups of population are also described. The results of the study showed that, after controlling for other variables, higher levels of household wealth were associated with lower fertility. There were also significant effects of participation of female labour force, ethnicity, age-at-marriage, and parity on current fertility. However, after controlling for wealth and other explanatory variables, the effect of female education was not significant. If the model were to remain constant over time, raising levels of wealth would reduce marital fertility in Sri Lanka.  相似文献   
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