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61.

Background

The transmission of sleeping sickness occurs primarily in rural areas, and exposed populations are those living from rural activities such as agriculture, fishing, animal husbandry or hunting. However, urban and suburban foci are more and more reported in T. b. gambiense areas. In Libreville town, sleeping sickness cases are regularly diagnosed. In order to investigate about the establishment of a transmission cycle of that disease, we have carried out an entomological survey in two quarters in the vicinity of the town.

Methods

Vavoua traps were set out in all suitable biotopes for tsetse flies during four days and examined twice a day. Flies were collected, identified and dissected.

Results

Two species of Glossina were caught: G. palpalis palpalis (90.58%) and G. caliginea (9.42%). A total infection rate of 9.37% was observed after dissection of all non-teneral flies captured.

Conclusion

These results suggest the establishment of a trypanosomiasis transmission cycle in the area. No salivary gland was found infected. Given that infected persons are regularly detected, we can think about the existence of a suburban sleeping sickness focus in Libreville. More analysis is needed concerning the identification of human trypanosomes and the origin of Glossina blood meals that may confirm the existence of that focus.  相似文献   
62.
利用固相法合成了二十个含羟基氨基酸的小肽。其中,以0.5mol·L-1二甲二氯硅烷/1.5mol·L-1苯酚/DCM*为脱除Boc试剂,以TFMSA为切除树脂试剂。经C-18反相柱纯化后,全部产物均通过氨基酸分析要求。体外黄体细胞分泌孕酮实验表明有八个肽化物GlyTyrAlaLys,(SarSer)2Lys及其申酯,TyrLys,HisTyr-NH2,ThrProTyrLys-NH2,TyrThrProArgLys,AspHisProThr-PheLys显示较强的抑制hCG致孕酮分泌的活性,而且前三个肽还能显著抑制基础孕酮的分泌,相反,GlySerTyr能刺激基础孕酮的分泌。目前尚未建立合理的结构一活性关系。  相似文献   
63.
Summary: Resolution of tubulointerstitial nephritis represents an important step in limiting renal fibrogenesis. However, the mechanism of this resolution remains poorly understood. to determine if apoptosis has a role in this process, we studied its incidence in an experimental model of renal infection and scarring, induced by direct inoculation of Escherichia coli into the renal cortex of Sprague-Dawley rats. the focal lesion produced was studied in animals killed at various time points up to 100 days post inoculation. Apoptosis was identified by electron microscopy (EM) and in-situ labelling of fragmented DNA using terminal transferasemediated deoxy-uridine-5'-triphospate (UTP) nick end labelling (TUNEL). Results were compared with morphological assessment of tubulointerstitial cellularity and macrophage localization. Terminal transferasemediated UTP nick end labelling localized apoptosis to interstitial cells, tubular casts and occasional tubular epithelia and double labelling demonstrated apoptotic body incorporation in macrophages. Interstitial cellularity was maximum at day 3, decreasing significantly by 100 days ( P < 0.01). the incidence of interstitial apoptosis was increased by 3 days and remained significantly higher than day 0 controls throughout ( P < 0.05). Tubular cellularity was significantly less than in control animals throughout the experimental time period. Although the rate of tubular apoptosis was increased, this difference was not statistically significant. In conclusion, apoptosis may represent an important mechanism in the reduction of tubulointerstitial cellularity after experimental renal infection. This in turn, may be important in limiting subsequent interstitial scarring.  相似文献   
64.
HPLC测定鼻炎糖浆中黄芩苷的含量   总被引:4,自引:0,他引:4  
目的建立测定鼻炎糖浆中黄芩苷的HPLC测定方法。方法黄芩苷测定以KYWG-C18为固定相,甲醇-水-磷酸(47∶53∶0.2)为流动相,UV检测波长为278nm。结果黄芩苷在0.06~0.01mg/ml浓度范围内与峰面积呈直线关系。回归方程为Y=-1.46×104+1.98×104X,r=0.9996,平均回收率为102.91%,日内和日间RSD均低于5%。结论本法测定鼻炎糖浆中黄芩苷的含量简便、准确、快捷,可用于鼻炎糖浆的质量控制。  相似文献   
65.

Background and purpose:

It has been previously shown that high levels of nitric oxide (NO), from NO donors, kill neurones, but the mechanisms are unclear.

Experimental approach:

The effects of NO donors on the electrical properties of rat cultured cerebellar granule cells (CGC neurones) were investigated using the whole-cell patch-clamp technique.

Key results:

The NO donor (Z)-1-[2-(2-aminoethyl)-N-(2-ammonioethyl)amino]diazen-1-ium-1,2-diolate (DETA-NONOate or NOC-18) caused a rapid, persistent, but fully reversible inward current that was associated with an increase in baseline noise and was concentration dependent (100 µM–10 mM). The response to 3 mM DETA-NONOate was completely inhibited by 1 mM gadolinium, but not by NO scavengers (1 mM haemoglobin or 1 mM PTIO) or glutamate receptor antagonists (10 µM MK-801 or 60 µM CNQX). Application of decomposed 3 mM DETA-NONOate or 3 mM nitrite had no effect. In contrast, the NO donor S-nitrosoglutathione (GSNO) caused a rapid, persistent, but fully reversible outward current that was also concentration dependent (1–10 mM). The 3 mM GSNO response was unaltered by NO scavengers, glutamate antagonists or gadolinium, but was mimicked by decomposed 3 mM GSNO and 3 mM oxidized glutathione.

Conclusions and implications:

These results suggest that DETA-NONOate directly activates cation-selective channels, causing an inward current in CGCs. In contrast, GSNO causes an outward current in these cells. Some of the effects of these NO donors are independent of NO, and thus caution is required in interpreting results when using high concentrations of these compounds.  相似文献   
66.
Preterm birth remains one of the serious problems in perinatal medicine and is associated with an increased risk of neonatal complications and long-term morbidity. Although each day that delivery is delayed between 22 and 28 weeks of gestation increases survival by 3%, since most spontaneous preterm labour occurs between 28 and 34 weeks of gestation, this is of secondary concern; the primary goal of delay is to improve the function of certain systems in the fetus and to balance the risks of a hostile intrauterine environment with the complications of extrauterine preterm life. Although there is a lack of definitive evidence that tocolytic drugs improve outcome following spontaneous preterm labour and preterm birth, there is ample evidence that tocolysis delays delivery for long enough to permit administration of a complete course of antepartum glucocorticoids and to facilitate in utero transfer to a tertiary care unit where neonatal care will be optimal. Both these measures have been associated with improved outcomes; antepartum glucocorticoids reduce the incidence of respiratory distress syndrome, intraventricular haemorrhage, periventricular leucomalacia and necrotising enterocolitis, and in utero transfer is associated with decreased morbidity and mortality and less hospital-based intervention compared with postnatal transportation. Consequently, women who are more likely to benefit from tocolysis are those at early gestational ages, those needing transfer to a hospital that can provide neonatal intensive care and those who have not yet received a full course of antepartum glucocorticosteroids. In these cases, delaying labour for at least 48 hours with drugs such as atosiban should be considered, since it offers clear advantages for the fetus.  相似文献   
67.
68.
Résumé: Malgré une incidence croissante du cancer du sein dans la population agée, les données spécifiques prospectives concernant sa prise en charge après 70 ans, tout particulièrement pour les indications de chimiothérapie adjuvante, sont rares dans la littérature, gênant l’application de recommandations standards établies essentiellement chez les sujets plus jeunes. La plupart des données dérivent d’essais multicentriques ayant étendu l’age limite supérieur d’inclusion à 65 ou 70 ans. Un seul essai multicentrique, fran?ais, a spécifiquement abordéle r?le d’une chimiothérapie adjuvante à base d’anthracyclines ajoutée au tamoxifène chez le sujet de plus de 65 ans. Pourtant plusieurs revues rétrospectives de groupes coopérateurs internationaux semblent démontrer lemame béneéfice potentiel d’une chimiothérapie adjuvante chez les sujets agés que chez les sujets plus jeunes, sous réserve d’une vigilance accrue à l’égard des effets secondaires. Avec l’aide ajustée d’échelles spécifiques gériatriques, les cliniciens doivent apprendre à intégrer bénéfice absolu, espérance de vie et tolérance, trois volets essentiels pour abandonner la discrimination ancienne reposant sur l’age, inadaptée à l’évolution de nos moyens et pratiques.   相似文献   
69.
70.
ObjectiveTo evaluate the effect of aqueous leaf extract of Guiera senegalensis (G. senegalensis) on gastric mucosal damage using different ulcer models.MethodsConsidering the above claims, the present study was undertaken to validate the gastroprotective potential of the aqueous leaf extract of this plant against ethanol, water immersion and Aspirin induced ulcer models.ResultsThe leaf extract (50, 100 and 200 mg/kg, p.o.) significantly (P<0.05) decreased the ulcer index in all assays used.ConclusionsThe results obtained, provide strong evidence of antiulcer activity of the leaf extract of G. senegalensis and support the traditional uses of the plant for the treatment of ulcer.  相似文献   
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