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991.
The morphological expression of keratinolysis in fungi isolated from the air of Torino (98 isolates belonging to 36 species) was studied. Light microscopy on whole material and on semithin sections, as well as scanning electron microscopy was used. There were 19 keratinolytically active species, with seven in the genusChrysosporium (C. indicum, C. keratinophilum, C. pannicola, C. tropicum, C. an.Arthroderma cuniculi, C. an.Pectinotrichum llanense, C. an.Renispora flavissima), four in the genusMalbranchea (M. arcuata, M. fulva, M. sulphurea, M. st.Uncinocarpus reesii), and three in the genusTrichophyton (T. mentagrophytes, T. rubrum, T. terrestre). In addition there wereAphanoascus fulvescens, Beauveria bassiana, Geomyces pannorum v.pannorum, Gymnoascus umbrinus andMyceliophthora vellerea. Most of these species were capable of developing structures related to surface erosion and radial penetration contemporaneously. HoweverGymnoascus umbrinus, Myceliophthora vellerea, an isolate ofC. indicum, C. tropicum andTrichophyton mentagrophytes demonstrated only surface erosion. Different isolates of one species can vary in their production of invasive structures and in degree of keratinolytic activity. Thus such activity, like many biochemical activities of fungi, does not appear to be a constant or rigorously species-specific character. 相似文献
992.
33个黄花菜品种及3种野生黄花菜的过氧化物酶同工酶分析 总被引:1,自引:0,他引:1
1984-1987年先后全国16个省区收集了33个黄花菜(HemerocalliscitrinaBarani)品种和3个野生黄花菜品种。87-94年连续7年观察了各品种的主要形态特征,农艺性状。利用聚丙烯酰胺凝胶电泳技术分析比较了各品种的过氧化物酶同工酶谱。结果表明,凡形态上差异较大者,过氧化物酶谱同工酶谱差异也大;形态上无明显差异者,过氧化物酶同工酶谱也基本相同,表现了很强的对应性。各地栽培的黄花菜中普遍存在着同物异名或同名异物现象。收集的33个黄花菜品种整理归并为25个不同的品种;17号早黄花(野生)、19号四月花(栽培)均为北萱草(Hemerocallisesculents),18号野黄花为折叶萱草(Hemerocallisplicata)。为研究黄花菜品种的亲缘起源关系及进行杂交育种工作提供了一些理论依据。 相似文献
993.
水稻“多胚苗”的形态学观察 总被引:5,自引:0,他引:5
“无融合多胚苗”水稻C1001B和它的杂种C1001B×C1001A 的未成熟颖果1500 粒;田间和人工萌发的单苗、双苗和三苗实生苗共2702 株进行了形态解剖观察,结果如下:1.C1001B和它的杂交颖果中只含一个胚;2. 由单个胚萌发的双苗和三苗幼苗是多苗实生苗。双苗实生苗的侧苗1 和三苗实生苗的侧苗1 是由主苗基部胚芽鞘的腋芽所形成,侧苗2由侧苗1 基生叶的腋部发育而来。因此,多苗实生苗系同一个胚发育的主苗及其腋芽系统所组成;3. 颖果中胚的位置和朝向的变化和侧苗生长的两种类型,导致主苗与侧苗位置上的不同。至于已报道的水稻“多胚苗”形成的无融合生殖类型和推测尚有待提出胚胎学的论据。 相似文献
994.
摘要 目的:探讨七味白术散联合蒙脱石散对腹泻幼鼠肠道菌群及免疫功能影响的研究。方法:选择SD雄性幼鼠30只,随机分为对照组、模型组、七味白术散组、蒙脱石散组、七味白术散联合蒙脱石散组,对照组与模型组灌胃给予0.2 mL/10生理盐水,七味白术散组给予0.2 mL/10 g七味白术散,蒙脱石散组给予0.2 mL/10 g蒙脱石散,七味白术散联合蒙脱石散组给予0.2 mL/10 g七味白术散+0.2 mL/10 g蒙脱石散,5组每天定时灌胃一次,均连续给药7天。对比腹泻指数、平均稀便级、稀便率、脾重、胸腺重指数、血清淀粉酶、血清D-木糖水平、回肠、结肠、空肠黏膜厚度及小肠内容物细菌增殖。结果:与对照组相比,其他组脾重、胸腺重指数、血清淀粉酶及D-木糖水平、双歧杆菌、乳酸杆菌数量较低,腹泻指数、平均稀便级、稀便率、回肠、结肠、空肠黏膜厚度、大肠杆菌较高(P<0.05);与模型组相比,蒙脱石散组、七味白术散组、七味白术散联合蒙脱石散组的脾重、胸腺重指数、血清淀粉酶及D-木糖水平、双歧杆菌、乳酸杆菌数量较高,腹泻指数、平均稀便级、稀便率、回肠、结肠、空肠黏膜厚度、大肠杆菌较低(P<0.05);与蒙脱石散组相比,七味白术散组、七味白术散联合蒙脱石散组的脾重、胸腺重指数、血清淀粉酶及D-木糖水平、双歧杆菌、乳酸杆菌数量较高,腹泻指数、平均稀便级、稀便率、回肠、结肠、空肠黏膜厚度、大肠杆菌较低(P<0.05);与七味白术散组相比,七味白术散联合蒙脱石散组的脾重、胸腺重指数、血清淀粉酶、D-木糖水平、双歧杆菌、乳酸杆菌数量明显较高,腹泻指数、平均稀便级、稀便率、回肠、结肠、空肠黏膜厚度、大肠杆菌较低(P<0.05)。结论:七味白术散联合蒙脱石散可明显改善腹泻幼鼠的腹泻症状,可能与其可调整腹泻幼鼠肠道菌群及免疫功能有关。 相似文献
995.
摘要 目的:探讨嗜酸性粒细胞、调节性T细胞对慢性鼻窦炎伴鼻息肉的诊断及预后预测价值。方法:选取我院2020年3月到2023年3月收治的100例慢性鼻窦炎伴鼻息肉患者作为研究对象,将其分为慢性鼻窦炎伴鼻息肉组,选取同期来我院治疗的100例单纯慢性鼻窦炎患者作为慢性鼻窦炎组,另选取同期来我院体检的100名健康志愿者作为对照组。对比三组受检者嗜酸性粒细胞、调节性T细胞表达水平,并建立受试者工作特征(ROC)曲线,分析嗜酸性粒细胞、调节性T细胞对慢性鼻窦炎伴鼻息肉的诊断效能。随后对100例性鼻窦炎伴鼻息肉患者手术治疗后进行1年随访,依照患者的复发情况评价其预后情况,并分为两个亚组,将术后1年内复发的21例患者分为预后不良组,两未复发的79例患者分为预后良好组,对比两组患者一般临床情况,嗜酸性粒细胞、调节性T细胞表达水平,并分析嗜酸性粒细胞、调节性T细胞对慢性鼻窦炎伴鼻息肉的预后预测价值。结果:三组受检者嗜酸性粒细胞、调节性T细胞表达水平对比差异显著,慢性鼻窦炎伴鼻息肉组患者嗜酸性粒细胞(EOS)个数高于慢性鼻窦炎组和对照组,调节性T细胞(Tregs)水平低于慢性鼻窦炎组和对照组(P<0.05);通过绘制ROC曲线,确定EOS、Tregs其对慢性鼻窦炎伴鼻息肉的诊断效能,结果显示,EOS、Tregs两者联合对慢性鼻窦炎伴鼻息肉的诊断效能优于单一检测(P<0.05);预后良好组与预后不良组患者性别、年龄、BMI、吸烟史、饮酒史、白细胞介素-35(IL-35)、转化生长因子-β(TGF-β)、白细胞介素-1β(IL-1β)表达水平对比无明显差异(P>0.05),预后良好组与预后不良组患者病程、合并哮喘、合并变应性鼻炎、组织淋巴细胞占比、白细胞介素-10(IL-10)、肿瘤坏死因子-α(TNF-α)、EOS个数以及Tregs表达水平对比差异显著(P<0.05);logistic回归分析结果表明:合并哮喘、组织淋巴细胞占比、EOS个数以及Tregs为慢性鼻窦炎伴鼻息肉的预后独立影响因素(P<0.05)。结论:嗜酸性粒细胞、调节性T细胞不仅对慢性鼻窦炎伴鼻息肉的临床诊断具有重要价值,而且能够预测慢性鼻窦炎伴鼻息肉患者的预后情况,因此临床上对于EOS个数增加,Tregs降低的患者要及时改善治疗措施,预防患者预后不良的发生。 相似文献
996.
摘要 目的:探讨肠道菌群失调与抑郁症合并冠心病的相关性,并分析肠道菌群失调对抑郁症合并冠心病预后的预测价值。方法:选取我院2021年6月到2022年5月收治的80例抑郁症患者作为研究对象,将单纯抑郁症的49例患者分为抑郁症组,将合并冠心病的31例患者分为l联合组,另选取同期来我院体检的40名健康者分为对照组,对比三组患者肠道菌群情况,应用Spearman相关分析分析肠道菌群失调与抑郁症合并冠心病的相关性。随后,对31例抑郁症合并冠心病患者进行随访,将其分为预后良好组(n=21)和预后不良组(n=10),对比两组患者临床一般情况与肠道菌群情况,应用logistic回归分析分析肠道菌群对抑郁症合并冠心病的预后预测价值。结果:三组患者拟杆菌情况无明显差异(P>0.05),肠杆菌、肠球菌、双歧杆菌、乳杆菌和双歧杆菌属与肠杆菌科细菌数量比(B/E)值对比差异显著,l联合组肠杆菌、肠球菌明显高于抑郁症组和对照组,双歧杆菌、乳杆菌、B/E值明显低于抑郁症组和对照组(P<0.05);Spearman相关分析结果显示:肠道菌群失调中拟杆菌水平与抑郁症合并冠心病无明显相关性(P>0.05),肠道菌群失调中肠杆菌、肠球菌水平与抑郁症合并冠心病呈正相关,与双歧杆菌、乳杆菌和双歧杆菌属与肠杆菌科细菌数量的对数值比(B/E)值呈负相关(P<0.05);预后良好组与预后不良组、年龄、BMI、合并基础疾病、hs-cTnT、NT-proBNP、NT-proBNP、PHQ-9评分、拟杆菌对比无明显差异(P>0.05),hs-CRP、肠杆菌、肠球菌、双歧杆菌、乳杆菌、B/E值对比差异显著(P<0.05);logistic回归分析结果表明:只有hs-CRP和B/E值菌群失调对于抑郁症合并冠心病的预后具有独立预测价值(P<0.05)。结论:抑郁症合并冠心病患者较单一抑郁症和健康者来说肠道菌群比例出现失调,且肠道菌群失调与抑郁症合并冠心病呈明显相关性,应用B/E 值可对抑郁症合并冠心病患者预后情况进行预测。 相似文献
997.
Interaction of filipin and amphotericin B with sterols in phosphatidylcholine membranes has been studied using various spin probes; epiandrosterone, cholestanone, phosphatidylcholine with 12-nitroxide or 5-nitroxide stearate attached to 2 position and also with tempocholine at the head group. Filipin caused increase in the fluidity of cholesterol-containing phosphatidylcholine membranes near the center, while it rather decreased the fluidity near the polar surface. On the other hand, amphotericin B did not apparently affect the fluidity. In the electron spin resonance spectrum of steroid spin probes in the antibiotic-containing membranes, both bound and free signals were observed and the association constant was calculated from the siganal intensity. In the binding of steroids with filipin, both 3 and 17 positions were involved, while the 17 position was less involved in the binding with amphotericin B. Phase change in the host membrane markedly affected the interaction of filipin with epiandrosterone probe. The bound fraction jumped from 0.4 to 0.8 on going to the crystalline state and increased further with decrease in temperature. The overall splitting of the bound signal also increased on lowering the temperature below phase transition. This change was attributed to aggregate formation of filipin-steroid complexes in the crystalline state. On the other hand, effect of phase transition was much smaller on the interaction of amphotericin B with the steroid probe. 相似文献
998.
EA, i.e., antigen-antibody complexes are able to induce an antigen-nonspecific suppressive factor(s) from FcR+ B cells by binding on FcR. This factor, termed “suppressive B-cell factor (SBF)” was only effective on H-2 compatible, but not on H-2 incompatible spleen cells in an adoptive cell transfer system. Furthermore, SBF, prepared from B10.A (H-2a) splenic FcR+ B cells, suppressed the adoptive primary response of B10.D2 mice (H-2d), in addition to A/J mice (H-2a) against DNP-DE, by the pretreatment of cells with SBF in vitro. Absorption with affinity columns demonstrated that active components) of SBF from C3H/He mice (H-2k) was eliminated by both B6 anti-CBA (H-2b anti-H-2k) and B10.D2 anti-B10.BR (H-2d anti-H-2k), but not B10 anti-B10.A (H-2b anti-H-2a). In contrast, the suppressive activity of SBF was eliminated neither by anti-mouse Ig nor by a heat-aggregated human γ-globulin column. These results indicate that SBF contains a product coded by the right-hand side of H-2 gene complex, but does not contain Ig determinants nor FcR. Thus, it is conceivable that a compatibility of the right-hand side of H-2 gene complex is required for inducing effective suppression of spleen cells by SBF. SBF was considered to be a trypsin-resistant and heat-labile substance with a molecular weight of 30,000–63,000. The target cells for SBF were FcR? B precursors, but not helper T cells. 相似文献
999.
The 10-R2 strain of Biomphalaria glabrata was strongly resistant to various strains of Schistosoma mansoni in its laboratory of origin (NIH) and to three strains of S. mansoni we tested against it. However, subsequent development of three inbred lines of B. glabrata 10-R2 snails, separately maintained in our San Francisco laboratory, showed slight loss of resistance in one colony, very much less resistance (or partial susceptibility) in another, and retention of the original resistance in a third to the Puerto Rico (PR-1) strain of S. mansoni. No selection for resistance to infection was involved in the breeding protocol for these 10-R2 lines, so the changes were apparently random ones that became established in the separate inbred substrains. In spite of their changed response to the PR-1 strain of S. mansoni, all three 10-R2 substrains retained only slightly diminished resistance to S. mansoni Lc-1 strain and an essentially undiminished resistance to irradiated Echinostoma lindoense, E. paraensei and E. liei sporocysts. This suggests that natural resistance to S. mansoni PR-1 in B. glabrata is specific, a response that differs from the host response to either S. mansoni Lc-1 or to the echinostomes. 相似文献
1000.
George Nakos 《Plant and Soil》1979,53(4):427-443
Summary Chemical analysis of samples of needles of Aleppo pine (Pinus halepensis), humus and mineral soil collected in the vicinity of the Pb-smelter in Lavrion, Attica, showed that an area of about 2 km around the smelter is heavily polluted primarily with Pb and also with Zn, S and F–. Most of the Pb was found accumulated in the humus and the top layer of the mineral soil.About 50% of the Pb found in the samples of Aleppo pine needles could be removed by washing them in a dilute detergent solution. One and 15% of the total Pb from Pb-polluted soil and humus samples, respectively, was extracted with normal ammonium acetate solution. No Pb or a very small amount was extracted with distilled H2O from humus and soil samples treated with concentrations of Pb as high as 3000 ppm and incubated in the laboratory for 30 days.Humus samples treated with up to 1500 ppm Pb or Pb-polluted humus samples collected from points leeward of the smelter had no adverse effects on the germination of Aleppo pine seeds. When the germination experiment was conducted on Pb-polluted humus samples from points windward of the smelter, where a temporary pine needle death had been observed, the percentage seed germination, for two years, was found reduced and negatively correlated to the distance of the humus sampling point from the Pb-smelter.In nursery experiments Pb concentrations of up to 2000 ppm, added to a calcareous soil, had no adverse effect on height increase of Aleppo pine seedlings. Very little Pb was transported from the roots to the needles after seven months growth of the seedlings on either Pb-amended soil or on Pb-polluted soil from Lavrion. Concentrations of Pb in the roots of the seedlings, however, were found high in both cases and almost proportional to concentrations of Pb in the soil. 相似文献