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101.
There is a growing understanding of risks posed by human contact with the cercariae of bird schistosomes. In general, there are no fundamental biological differences between human and bird schistosomes in terms of their interactions with snail and vertebrate hosts. The penetration of host surfaces is accompanied by the release of penetration gland products and the shedding of highly antigenic surface components (miracidial ciliated plates and cercarial glycocalyx) which trigger host immune reactions. New surface structures are formed during transformation: the tegument of mother sporocysts and the tegumental double membrane of schistosomula. These surfaces apparently serve as protection against the host immune response. Certain parasite excretory-secretory products may contribute to immunosuppression or, on the other hand, stimulation of host immune reactions. Discovery of new species and their life cycles, the characterization of host-parasite interactions (including at the molecular level), the determination of parasite pathogenicity towards the host, the development of tools for differential diagnosis and the application of protective measures are all topical research streams of the future. Regularly updated information on bird schistosomes and cercarial dermatitis can be found at http://www.schistosomes.cz (web pages of Schistosome Group Prague). 相似文献
102.
Ana Lúcia Sousa Diamantino Sousa Pedro Figueiredo Pedro Pinto Marques Horácio Guerreiro 《World journal of gastrointestinal endoscopy》2013,5(10):519-522
Here we present the case of a 35-year-old female patient with long standing dyspepsia and imaging studies showing the presence of multiple cysts in the head and tail of the pancreas. The patient underwent endosonography that confirmed the presence of multiple simple cysts throughout the entirety of the pancreas without dilation of the pancreatic duct. The majority of the cysts were less than one centimeter in size, and the largest cyst showed a honeycomb appearance. Cytology of aspirates from the two largest cysts was compatible with benign pancreatic cysts. Endosonography also revealed cysts within the left kidney and spleen. Genetic testing confirmed Von Hippel-Lindau disease. We highlight this case because it is unusual for Von Hippel-Lindau disease, a rare clinical entity, to present solely with cysts in the absence of more common manifestations, such as hemangioblastomas in the central nervous system and malignancy. 相似文献
103.
S Hollán I Dey L Szollár M Horányi M Magócsi V Harsányi T Farkas 《Proceedings of the National Academy of Sciences of the United States of America》1995,92(1):268-271
Marked hypoalphalipoproteinemia was found together with relatively low serum cholesterol, triacylglycerol, and LDL levels in a triose-phosphate isomerase (TPI; D-glyceraldehyde-3-phosphate ketol-isomerase, EC 5.3.1.1)-deficient Hungarian family, especially in the two compound-heterozygote brothers. Apart from a slight increase in palmitic and stearic acids together with a slight decrease in oleic and linoleic acids, no other changes were found in the fatty acid composition of the erythrocyte phospholipids. Anisotropy measurements with n-(9-anthroyloxy) stearic and -palmitic acid fluorophores revealed increased motional freedom of the fatty acid chains in the external lipid layers of the intact erythrocytes from all members of the TPI-deficient family as compared with normal age-matched controls. This asymmetric increase in membrane fluidity was found to be significantly higher in the propositus than in his compound-heterozygote brother without any neurological disorders. The change in membrane fluidity may result from as-yet-unresolved aspects of the lipid composition of the plasma membrane. Our findings that the differences between the TPI-deficient individuals and normal controls and the differences between the two compound-heterozygote brothers were all absent in the phospholipid extracts of the same erythrocytes favor the assumption that the increased motional freedom of the fatty acid chains in the external surface of the bilayer is caused by the binding of the mutant TPI molecule to the N-terminal sequence of band 3 protein. 相似文献
104.
Lord BI; Woolford LB; Wood LM; Czaplewski LG; McCourt M; Hunter MG; Edwards RM 《Blood》1995,85(12):3412-3415
BB-10010 is a genetically engineered variant of human macrophage inflammatory protein-1 alpha with improved solution properties. We show here that it mobilizes stem cells into the peripheral blood. We investigated the mobilizing effects of BB-10010 on the numbers of circulating 8-day spleen colony-forming units (CFU-S8), CFU-S12, and progenitors with marrow repopulating ability (MRA). A single subcutaneous dose of BB-10010 caused a twofold increase in circulating numbers of CFU-S8, CFU-S12, and MRA 30 minutes after dosing. We also investigated the effects of granulocyte colony-stimulating factor (G- CSF) and the combination of G-CSF with BB-10010 on progenitor mobilization. Two days of G-CSF treatment increased circulating CFU-S8, CFU-S12, and MRA progenitors by 25.7-, 19.8-, and 27.7-fold. A single administration of BB-10010 after 2 days of G-CSF treatment increased circulating CFU-S8, CFU-S12, and MRA even further to 38-, 33-, and 100- fold. Splenectomy resulted in increased circulating progenitor numbers but did not change the pattern of mobilization. Two days of treatment with G-CSF then increased circulating CFU-S8, CFU-S12, and MRA by 64-, 69-, and 32-fold. A single BB-10010 administration after G-CSF treatment further increased them to 85-, 117-, and 140-fold, respectively, compared with control. We conclude that BB-10010 causes a rapid increase in the number of circulating hematopoietic progenitors and further enhances the numbers induced by pretreatment with G-CSF. BB- 10010 preferentially mobilized the more primitive progenitors with marrow repopulating activity, releasing four times the number achieved with G-CSF alone. Translated into a clinical setting, this improvement in progenitor cell mobilization may enhance the efficiency of harvest and the quality of grafts for peripheral blood stem cell transplantation. 相似文献
105.
Artur Gião Antunes Cristina Teixeira Ana Margarida Vaz Cláudio Martins Patrícia Queirós Ana Alves Francisco Velasco Bruno Peixe Ana Paula Oliveira Horácio Guerreiro 《Gastroenterologia y hepatologia》2017,40(4):276-285
Background and aim
Recently, the European Association for the Study of the Liver – Chronic Liver Failure (CLIF) Consortium defined two new prognostic scores, according to the presence or absence of acute-on-chronic liver failure (ACLF): the CLIF Consortium ACLF score (CLIF-C ACLFs) and the CLIF-C Acute Decompensation score (CLIF-C ADs). We sought to compare their accuracy in predicting 30- and 90-day mortality with some of the existing models: Child-Turcotte-Pugh (CTP), Model for End-Stage Liver Disease (MELD), MELD-Na, integrated MELD (iMELD), MELD to serum sodium ratio index (MESO), Refit MELD and Refit MELD-Na.Methods
Retrospective cohort study that evaluated all admissions due to decompensated cirrhosis in 2 centers between 2011 and 2014. At admission each score was assessed, and the discrimination ability was compared by measuring the area under the ROC curve (AUROC).Results
A total of 779 hospitalizations were evaluated. Two hundred and twenty-two patients met criteria for ACLF (25.9%). The 30- and 90-day mortality were respectively 17.7 and 37.3%.CLIF-C ACLFs presented an AUROC for predicting 30- and 90-day mortality of 0.684 (95% CI: 0.599–0.770) and 0.666 (95% CI: 0.588–0.744) respectively. No statistically significant differences were found when compared to traditional models. For patients without ACLF, CLIF-C ADs had an AUROC for predicting 30- and 90-day mortality of 0.689 (95% CI: 0.614–0.763) and 0.672 (95% CI: 0.624–0.720) respectively. When compared to other scores, it was only statistically superior to MELD for predicting 30-day mortality (p = 0.0296).Conclusions
The new CLIF-C scores were not statistically superior to the traditional models, with the exception of CLIF-C ADs for predicting 30-day mortality. 相似文献106.
107.
细胞核仁形成区酸性非组蛋白在胆囊癌诊断与监测中的价值 总被引:3,自引:0,他引:3
目的探讨检测细胞核仁形成区酸性非组蛋白在胆囊癌诊断与监测中的价值。方法应用细胞银染技术对体外激活的外周血和胆汁淋巴细胞染色 ,并对胆囊组织作核仁形成区嗜银蛋白银染 ,计算外周血和胆汁中硝酸银染色酸性非组蛋白 (Ag) NORs面积与核面积的比值 (IS % )和组织切片中AgNOR颗粒面积。结果正常人 (2 0例 )、慢性胆囊炎 (90例 )与胆囊癌之间 (2 1例 )外周血、胆汁T细胞Ag NORs面积与核面积的比值和组织切片中AgNOR面积差异均有显著性意义 ,血清、胆汁中T细胞Ag NORs面积与核面积的比值 (IS % )逐级降低 ,组织切片中AgNOR面积逐级升高 ,且血清、胆汁中T细胞Ag NORs面积与核面积的比值 (IS % )、组织中AgNOR面积三者相互间有良好的直线相关性 (P均 <0 0 1)。结论监测胆囊病变过程中患者外周血、胆汁中T细胞Ag NORs面积与核面积的比值 (IS % )和组织切片中AgNOR面积的变化 ,有助于胆囊癌的诊断 相似文献
108.
J. Breza H. M. Alemayehu M. Horňák V. Zvara 《International urology and nephrology》1994,26(4):447-453
A modified Mainz pouch with catheterizable stoma was constructed in six patients who had originally undergone incontinent
urinary diversion by ureteroileostomy 7 to 22 years previously for bladder exstrophy or neurogenic bladder with total urinary
incontinence. The surgical technique differed from the standard as follows: after stomal excision, the preexisting ileal loop
was detubularized and combined with additional ileal and colonic segments for pouch construction. In patients in whom the
original ureteroileal anastomoses were patent and the contrast medium refluxed freely to the upper urinary tract during loopography,
the ureters were not reimplanted but kept intact. In all patients the ileal valve was connected as stoma to the umbilicus.
In addition, two patients underwent construction of a standard Mainz pouch. One had had primary ureterosigmoidostomy and the
other one ureterostomies, 10 and 3 months previously, respectively. The urodynamic characteristics of the reservoir were normal
in all. In six ureteropelvic units dilation improved significantly and in two patients the bilateral loop-ureter reflux diminished.
Long-term follow-up (up to 45 months) showed no further impairment of the kidneys. 相似文献
109.
合欢皮中新皂甙的结构鉴定 总被引:7,自引:2,他引:5
从合欢皮(Albizziae cortex)的95%乙醇提取物的正丁醇萃取部分中分离得到3个新的三萜皂甙,用化学方法及1H-和13C-NMR,DEPT,COSY,TOCSY,HMQC-COSY,HMQC-TOCSY,HMBC,NOESY等波谱方法鉴定其结构为:I(1个三萜,9个糖,2个单萜),命名为合欢皂甙(julibroside)J1;II(1个三萜,8个糖,2个单萜),命名为合欢皂甙J2;II(1个三萜,9个糖,2个单萜),命名为合欢皂甙J3。 相似文献
110.
柴胡皂甙q及其甙元的结构鉴定 总被引:4,自引:0,他引:4
从小叶黑柴胡(Bupleurum smithii Wolffvar;parvifolium ShanetY.Li)的根中得到3个化合物,柴胡皂甙元A和Q及柴胡皂甙q。柴胡皂甙元Q和柴胡皂甙q为新化合物,根据理化性质和波谱分析,确定其结构分别为齐墩果烷-11,13(18)-二烯-3β,16β,23,28,30-五醇和3β,16β,23,28,3O-五羟基齐墩果烷-11,13(18)-二烯-3-O-β-D-吡喃葡萄糖基(1→6)-[α-L-吡喃鼠李糖基(1→4)]-β-D-吡喃葡萄糖甙。 相似文献