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71.
Gaetano Scala Paolo De Girolamo Mario Corona Gaetano Vincenzo Pelagalli 《Anatomical record (Hoboken, N.J. : 2007)》2002,266(1):58-68
The microvasculature of the water buffalo (Bubalus bubalis) epididymis was investigated using light (LM), scanning electron (SEM), and transmission electron (TEM) microscopy techniques. SEM analysis of the buffalo epididymis showed fenestrations that occupied ovoid inside the endothelium of the postcapillary venules located in the caput, corpus, and cauda. They varied in shape and dimension, but more importantly, they connected the venules of the blood vascular system to the capillaries of the peripheral lymphatic vascular system. Morphofunctional analysis of these connections suggests that the microvasculature of the buffalo epididymis plays a role in facilitating the circulation of biologically active substances, and the absorption and secretion processes necessary for the survival and maturation of spermatozoa. The lymphatic capillaries at the connection points formed a network of variously sized polygonal links. These capillaries then converged to form the precollector lymphatic vessels, which in turn converged with the larger vessels originating from the testis. It was further noted that in the capillary endothelium there were no fenestrations, and in the large veins there were many diverticula. These diverticula appear to play a role in the regulation of the seasonal variations of the blood reflux. In general, the microvascular architecture of the buffalo epididymis, particularly its connection to the lymphatic vascular system, appears to play an important role in the absorption and secretion processes of the epididymal epithelium. Anat Rec 266:58–68, 2002. © 2002 Wiley‐Liss, Inc. 相似文献
72.
73.
Okamura A Yazawa S Nishimura T Tanaka S Takai I Kudo S Asao T Kuwano H Matta KL Akamatsu S Kochibe N 《Clinical & experimental metastasis》2000,18(1):37-43
A new ex vivo method for assaying adhesion of cancer cells to the greater omentum has been developed using mouse greater omentum and [3H]labelled human gastric and mouse colorectal cancer cells. Since the adhesion rates were found to increase up to 18 h and labelled cells seemed to be stable during the period, the present method could be useful for investigating adhesion of cancer cells to the greater omentum, which must occur at the first step of the peritoneal dissemination. The adhesion of cancer cells to the greater omentum was inhibited by a series of chemically synthesized oligosaccharides and Galβ1,3[3OMeGalβ1,4GlcNAcβ1,6]αBn was found to be the best inhibitor. The anti-tumor effect of this novel tetrasaccharide in vivo was shown in preliminary experiments using Balb/c mice and colon26 cells. 相似文献
74.
Paris A Goutal I Richard J Bécret A Guéraud F 《APMIS : acta pathologica, microbiologica, et immunologica Scandinavica》2001,109(5):365-375
In comparison to estradiol-17beta, the naturally synthesized estradiol-17beta-17-fatty acid esters are potent estrogens when administered subcutaneously. A lipophilic character of estradiol-17-esters could partially protect them from metabolic inactivation. In order to compare their relative estrogenic potency when administered orally, the uterotrophic response to different dosages (0, 2.5, 25, 250 and 2500 nmol/kg BW/day) of estradiol-17beta and estradiol-17beta-17-stearate was assessed in juvenile Sprague-Dawley female rats. Estrogens were administered by oral gavage once a day for 6 days. On the 7th day uterus and vagina were dissected, weighed, and examined microscopically. At 2.5 and 25 nmol/kg BW/day, no difference was detected in the uterus weight compared to control animals which received the vehicle alone (corn oil). At 250 nmol/kg BW/day, the uterotrophic response was maximal in estradiol-17beta-17-stearate-treated animals (x2.40-2.70), whereas it was moderate in estradiol-17beta-treated rats (x1.86) at the same dosage. This differential weight gain effect of estradiol-17beta-17-stearate was correlated with typical microscopic changes in uterus and vagina. The results are in favour of a stronger estrogenic effect of orally given lipoidal estrogens compared to estradiol-17beta. This could be explained by a slower but sustained absorption of estradiol-17beta released from estradiol-17beta-17-stearate by esterases and/or by a facilitated transfer of esters in the lymphatic circulation. 相似文献
75.
本实验比较糖元、鸡红细胞及两者复合使用对小鼠腹腔渗出细胞的影响,结果表明鸡红细胞和糖元一样能激活巨噬系和组织嗜碱系细胞,影响巨噬系细胞分化,鸡红细胞较糖元快;而影响组织嗜碱系细胞分化,糖元较鸡红细胞快。由于腹腔渗出细胞中存在原、幼巨噬细胞,按照血细胞发育是不可逆回的理论,推测腹腔巨噬细胞不是来源于血液循环中的单核细胞,而是来自血循环中的定向干细胞。本实验在腹腔渗出细胞中,首次发现组织嗜碱系细胞并描写其形态特征。 相似文献
76.
Philipp Kasten Gerrit Schnöink Astrid Bergmann Maria Papoutsi Kerstin Buttler Jochen Rössler Herbert A. Weich Jörg Wilting 《Developmental dynamics》2007,236(10):2952-2961
Lymphangioma is a disfiguring malformation of early childhood. A mouse lymphangioma model has been established by injecting Freund's incomplete adjuvant (FIA) intraperitoneally, but has not been compared with the human disease. We show that, in accordance with studies from the 1960s, the mouse model represents an oil-granuloma, made up of CD45-positive leukocytes and invaded by blood and lymph vessels. Several markers of lymphatic endothelial cells are expressed in both mouse and human, like CD31, Prox1, podoplanin, and Lyve-1. However, the human disease affects all parts of the lymphovascular tree. We observed convolutes of lymphatic capillaries, irregularly formed collectors with signs of disintegration, and large lymph cysts. We observed VEGFR-2 and -3 expression in both blood vessels and lymphatics of the patients, whereas in mouse VEGFR-2 was confined to activated blood vessels. The experimental mouse FIA model represents a vascularized oil-granuloma rather than a lymphangioma and reflects the complexity of human lymphangioma only partially. 相似文献
77.
Erythropoietin concentrations are elevated in the peritoneal fluid of women with endometriosis 总被引:5,自引:0,他引:5
Matsuzaki S Murakami T Uehara S Yokomizo R Noda T Kimura Y Okamura K 《Human reproduction (Oxford, England)》2001,16(5):945-948
Erythropoietin (Epo) is an important regulator of erythropoiesis and stimulates the proliferation of early erythroid precursors as well as the differentiation of late erythroid precursors of the erythroid lineage. However, recent studies have indicated that Epo also has angiogenic properties and plays an important role in the oestrogen-dependent cyclical angiogenesis within the mouse uterus. It was therefore postulated that Epo may be an important angiogenic factor in endometriosis. In order to address this hypothesis the concentration of Epo in peritoneal fluid (PF) was determined in patients with or without endometriosis. PF was collected from patients with endometriosis (n = 42) or without endometriosis (n = 18). Detectable concentrations of Epo were found in all PF samples analysed. The concentration of Epo in PF from patients with endometriosis was significantly higher than that in the control group (13.1 +/- 1.2 mIU/ml versus 7.2 +/- 0.7 mIU/ml, mean +/- SE respectively, P < 0.01). Furthermore, in patients with endometriosis the Epo concentrations in PF from patients with stage I disease (n = 17, 16.6 +/- 3.0 mIU/ml) were significantly higher than those with stage II (n = 8, 10.7 +/- 1.2 mIU/ml, P < 0.03), III (n = 13, 8.4 +/- 1.0 mIU/ml, P < 0.01), IV disease (n = 7, 7.5 +/- 1.0 mIU/ml, P < 0.01). These data suggest that Epo may play a role in the pathogenesis of endometriosis particularly in the initiation of the disease. 相似文献
78.
An autoradiographic method combined with a rosette technique was used to assess the bactericidal activity of individual control and inflammatory peritoneal macrophages (PM phi) in the presence or absence of expression of Fc receptor for IgG (FcR). There was a lack of FcR reactivity in a certain percentage of both categories of PM phi exposed to E. coli X43, a bacterium which is readily phagocytosed in the presence of specific antibody. Both rosetting and non-rosetting PM phi were capable of phagocytosing E. coli X43, but inflammatory PM phi showed a marked reduction in their capacity to ingest these bacteria compared with control PM phi. Once ingested the E. coli X43 were killed equally well by non-rosetting and rosetting control and inflammatory PM phi. 相似文献
79.
腹膜透析病人的焦虑和抑郁水平与其病情变化的相关分析 总被引:23,自引:0,他引:23
目的:探讨腹膜透析病人情绪障碍,即焦虑症状和抑郁症状的发生情况,以及与透析相关因素的关系.方法:88例腹膜透析病人,使用Hamilton焦虑量表和Hamilton抑郁量表评估其情绪状况,同时测定其营养状况、残余肾功能和透析充分性、以及炎症水平,记录心脑血管事件发生情况等.结果:本组腹膜透析病人焦虑症状的发生率为44.3%,抑郁症状的发生率为56.8%.具有糖尿病和心脑血管病史者的Hamilton焦虑评分和抑郁评分高于无此类病史者(P<0.05).SGA评分较高的病人Hamilton焦虑评分和抑郁评分也较高;焦虑评分和抑郁评分较高的病人,其血清白蛋白水平、蛋白质摄入水平、体重指数、上臂中段肌肉面积和脂肪面积均较低(r=0.22~0.60,P<0.05或P<0.01).结论:腹膜透析病人焦虑症状和抑郁症状的发生率较高,焦虑症状和抑郁症状与心脑血管系统疾病和糖尿病相关,并可能与营养不良的发生存在一定的关系. 相似文献
80.
APC from mice harbouring the filarial nematode, Brugia malayi, prevent cellular proliferation but not cytokine production 总被引:2,自引:0,他引:2
Specific T cell hyporesponsiveness and depressed antibody productionis a key feature of human infection with the filarial nematodes,Brugia malayi and Wuchereria bancrofti Despite this immune suppression,responses indicative of Th2 subset activation are present, includingunusually high levels of specific lgG4. We tested the possibilitythat infection with filarial nematodes causes a reduction inthe co-stimulatory or antigen-presenting capacity of macrophagesresulting in a failure to activate specific T cells. Adherentperitoneal exudate cells (PEC) from mice implanted with adultB. malayi were used to present antigen to the conalbumin-specificT cell clone, D10.G4. Proliferation of the D10 cells at evenbackground levels was completely blocked by the presence ofimplant-derived adherent PEC. However, cytokine production bythese cells in response to antigen was intact, and thus PECfrom implanted mice are capable of functionally processing andpresenting antigen. The elicitation of a suppressive cell populationwas specific for live adults as cells from mice implanted withdead adult parasites effectively stimulated D10 proliferation.The block in cellular proliferation is not due to the productionof factors typically associated with macrophage suppressionsuch as nitric oxide, prostaglandins or catalase. These observationsare consistent with the T cell hyporesponsiveness seen in humancases of patent Brugia infection and may provide a murine modelfor the immune suppression seen in lymphatic filariasis. 相似文献