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The phospholipid composition of platelets from dogs on various experimental diets was determined. Thyroidectomized foxhounds were fed a control diet or the control diet supplemented with (1) beef tallow, (2) beef tallow and cholesterol, or (3) beef tallow, cholesterol, and safflower oil for 23 weeks prior to isolation of platelets. Platelets from animals fed the control diet contained 36.7% phosphatidylcholine (PC), 22.8% phosphatidylethanolamine (PE), 18.4% sphingomyelin (Sph), 11.8% phosphatidylserine (PS), 6.3% phosphatidylinositol (PI), and 2.2% lysophosphatidylcholine. The PE was 77.6% in the plasmalogen form. No highly significant changes in the phospholipid class composition resulted from the experimental diets. Cholesterol supplementation of the diets, however, caused consistent alterations in the fatty acid compositions of the platelet phospholipids including increases in the percentages of 18∶1ω9 (oleic acid), 18∶2ω6 (linoleic acid), and 20∶3ω6 (homo-gamma linolenic acid) and a decrease in the percentage of 20∶4ω6 (arachidonic acid). Addition of safflower oil to the tallow-cholesterol diet partially reversed these effects. These cholesterol-induced alterations in fatty acid composition could be due to exchange with plasma lipids, de novo synthesis, or altered platelet metabolism. The mechanism remains to be determined. Der. Nelson’s current affiliation is the Lipid Metabolism Branch, Division of Heart and Vascular Diseases, National Heart, Lung, and Blood Institute.  相似文献   
3.
Five candidate pheromone components were identified by analyzing pheromone gland extracts by gas chromatography (GC), coupled GC-electroantennographic detection (EAD), and coupled GC-mass spectrometry (MS): (E)-11-hexadecenol(E11–16 : OH), (Z)-11-hexadecenol (Z11–16 : OH),(E)-11-hexadecenal, (E)-11-hexadecenyl acetate, and (Z)-3,(Z)-6,(Z)-9-tricosatriene (Z3,Z6,Z9–23 : Hy). In electroantennogram (EAG) recordings, synthetic E11–16 : OH elicited stronger antennal responses at low doses than other candidate pheromone components. Field tests demonstrated that synthetic E11–16 : OH as a trap bait was effective in attracting males, whereas addition of Z11–16 : OH inhibited the males' response. Z3,Z6,Z9–23 : Hy strongly enhanced attractiveness of E11–16 : OH, but was not attractive by itself. A pheromone blend with synergistic behavioral activity of an alcohol (E11–16 : OH) and hydrocarbon (Z3,Z6,Z9–23 : Hy) component is most unusual in the Lepidoptera. The synthetic two-component pheromone is approximately 60 times more attractive than the female-produced blend and might facilitate the control of this pest.  相似文献   
4.
Previous studies in the primate fetal adrenal gland have indicated that the gland is comprised of three functional zones: 1) the inner fetal zone (FZ), which has the enzymes necessary for dehydroepiandrosterone sulfate (DHEAS) production beginning early in gestation; 2) the transitional zone (TZ), which possesses enzymes necessary for cortisol production; and 3) the outer, definitive zone (DZ), which appears to function as a reservoir of progenitor cells that may populate the remainder of the gland and does not acquire a steroidogenic phenotype with the capacity to produce mineralocorticoids until near term. The enzymes CYP21A2 (P450 21 hydroxylase, or P450c21), CYP11B1 (11beta hydroxylase or P450c11) and CYP11B2 (aldosterone synthase) are necessary for glucocorticoid and mineralocorticoid synthesis but have not been localized previously in an ontogenic manner in the primate fetal adrenal gland. Therefore, we used immunocytochemistry (ICC) to assess specific zonal localization and developmental regulation of CYP21A2 and CYP11B1/CYP11B2 in the human (13-24 weeks' gestation) and rhesus monkey (109 d-term) fetal adrenal gland. In the fetal rhesus, ICC was performed with and without metyrapone administration to the fetus to assess the effects of endogenously increased fetal ACTH. In the human fetal adrenal, CYP21A2 immunoreactivity (IR) was present in only a few isolated cells in the DZ but was detectable in almost all cells in the TZ and FZ. In the fetal rhesus, CYP21A2-IR was present in cells throughout the DZ and TZ and, to a lesser degree, in the FZ. Staining intensity increased with advancing gestational age and was up-regulated in the DZ and TZ, but not the FZ, of the metyrapone-treated fetuses. In the human fetal adrenal gland, CYP11B1/CYP11B2-IR was absent in the DZ but present in the TZ and FZ. In the fetal rhesus monkey adrenal, CYP11B1/CYP11B2-IR was present in all cells of the TZ and FZ but was absent from the DZ until near term. After metyrapone, CYP11B1/CYP11B2-IR was induced in the DZ and was up-regulated in the TZ and FZ. Taken together, these data indicate that in the primate fetal adrenal gland, the FZ has the capacity to synthesize DHEA and DHEAS beginning early in development, the TZ has the capacity to synthesize cortisol after midgestation, and the DZ has the capacity to synthesize mineralocorticoids, but not until near term. The spatial localization of steroid metabolizing enzymes and steroid products in the human and rhesus monkey fetal adrenal suggests analogies of the three functional zones of the fetus (DZ, TZ, and FZ) to their adult counterparts (zona glomerulosa, zona fasciculata, and zona reticularis) and their steroid products (mineralocorticoids, glucocorticoids and androgens, respectively), although the reason for the presence of CYP11B1/CYP11B2- and CYP21A2-IR in the FZ remains to be elucidated.  相似文献   
5.
Lymph nodes contain nonlymphoid accessory cells including follicular dendritic cells (FDCs), interdigitating dendritic cells (IDCs) and fibroblastic reticular cells (FBRCs). Neoplasms derived from FDCs are uncommon, and those of IDC origin are even more rare. We report the clinicopathologic features of 11 reticulum cell neoplasms, including 2 of FBRC origin. There were seven male patients and four female patients ranging in age from 13 to 73 years. All cases involved lymph nodes (cervical or supraclavicular-6 cases), (abdominal--2 cases), epitrochlear (1 case); two had more than one site of involvement (cervical lymph node and mediastinum--1 case, cervical and abdominal lymph nodes--1 case). One case of FDC tumor had concomitant Castleman's disease, plasma cell variant. Each neoplasm showed similar histology with oval-to-spindle-shaped cells in a storiform or fascicular pattern. Based on immunophenotypic findings, the neoplasms were classified as FDC (five cases), IDC (two cases), FBRC (three cases), and reticulum cell neoplasm, not otherwise specified (one case). The FDC tumors showed immunoreactivity for CD21 or CD35, vimentin, and CD68. The IDC tumors showed strong positivity for S-100 protein and variable positivity for CD68 and CD1a. The cases derived from FBRCs were positive for vimentin, desmin, and smooth-muscle actin. The neoplasm classified as reticulum cell neoplasm, not otherwise specified had similar morphologic features but showed only equivocal positivity for CD68 and vimentin. Follow-up was available for 9 of 11 (82%) cases with a mean of 3.5 years. Four of five patients with FDC tumors were alive with disease when last seen; the fifth is alive and well with no evidence of disease at 4-year follow-up. One patient with IDC tumor had a recurrence in a different nodal site. Two patients with FBRC tumor were disease free at follow-up of 2 years and 8 years, respectively. The patient with reticulum cell neoplasm, not otherwise specified, was alive and disease free 8 years after diagnosis.  相似文献   
6.
The defects in lymphocyte apoptosis that underlie the autoimmune lymphoproliferative syndrome (ALPS) are usually attributable to inherited mutations of the CD95 (Fas) gene. In this report, we present the histopathological and immunophenotypic features seen in the lymph nodes (n = 16), peripheral blood (n = 10), bone marrow (n = 2), spleen (n = 3), and liver (n = 2) from 10 patients with ALPS. Lymph nodes showed marked paracortical hyperplasia. Interfollicular areas were expanded and populated by T cell receptor-alphabeta CD3+ CD4-CD8- (double-negative, DN) T cells that were negative for CD45RO. CD45RA+ T cells were increased in all cases studied. The paracortical infiltrate was a result of both reduced apoptosis and increased proliferation, as measured by in situ detection of DNA fragmentation and staining with MIB-1, respectively. The paracortical proliferation may be extensive enough to suggest a diagnosis of malignant lymphoma. Many of the paracortical lymphocytes expressed markers associated with cytotoxicity, such as perforin, TIA-1, and CD57. CD25 was negative. In addition, most lymph nodes exhibited florid follicular hyperplasia, often with focal progressive transformation of germinal centers; in some cases, follicular involution was seen. A polyclonal plasmacytosis also was present. The spleens were markedly enlarged, more than 10 times normal size. There was expansion of both white pulp and red pulp, with increased DN T cells. DN T cells also were observed in liver biopsies exhibiting portal triaditis. In the peripheral blood, the T cells showed increased expression of HLA-DR and CD57 but not CD25. CD45RA+ T cells were increased in the four cases studied. Polyclonal B cell lymphocytosis with expansion of CD5+ B cells was a characteristic finding. Taken together, the histopathological and immunophenotypic findings, particularly in lymph nodes and peripheral blood, are sufficiently distinctive to suggest a diagnosis of ALPS. Of note, two affected family members of one proband developed lymphoma (T-cell-rich B-cell lymphoma and nodular lymphocyte predominance Hodgkin's disease, respectively).  相似文献   
7.
Severe splenomegaly and anemia developed in a 5-year-old girl with diffuse lymphangiomatosis of the upper part of the body. Radioisotope scanning and celiac angiography demonstrated lymphangiomatosis of the spleen, a rare but diagnosable condition. Intractable infection in areas of ulcerated skin led to her death from overwhelming sepsis.  相似文献   
8.
We propose a method for concept-based medical image retrieval that is a superset of existing semantic-based image retrieval methods. We conceive of a concept as an incremental and interactive formalization of the user's conception of an object in an image. The premise is that such a concept is closely related to a user's specific preferences and subjectivity and, thus, allows to deal with the complexity and content-dependency of medical image content. We describe an object in terms of multiple continuous boundary features and represent an object concept by the stochastic characteristics of an object population. A population-based incrementally learning technique, in combination with relevance feedback, is then used for concept customization. The user determines the speed and direction of concept customization using a single parameter that defines the degree of exploration and exploitation of the search space. Images are retrieved from a database in a limited number of steps based upon the customized concept. To demonstrate our method we have performed concept-based image retrieval on a database of 292 digitized X-ray images of cervical vertebrae with a variety of abnormalities. The results show that our method produces precise and accurate results when doing a direct search. In an open-ended search our method efficiently and effectively explores the search space.  相似文献   
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Reviews the book, The domestic assault of women: Psychological and criminal justice perspectives by Donald A. Dutton (1988). This book provides a comprehensive analysis of battered women and their husbands by integrating current theories and research on violence and victimization within a social psychological perspective. The book is divided into seven chapters. The first chapter outlines the current data on the incidence of wife assault and proposes a theoretical framework for understanding the problem. The next two chapters outline the theory and research available on men who assault their partners. Chapter four details the impact of violence on victims and provides some explanations for battered women becoming "prisoners" in their own home. Chapter five details the shortcomings of the criminal justice response to battered women. Chapter six provides some more optimistic information on treatment programs for violent husbands. The book ends with a section on future trends, including current research programs on children who witness violence in their homes. Overall, the book is well written and demonstrates Dutton's excellent analytical skills. He has an ability to integrate diverse theoretical models on family violence with current research studies in the field. His understanding of battered women and their husbands flows dramatically into the dismal record of the criminal justice system in providing a meaningful response to the problem. His analysis of current treatment programs offers some valuable insight to the reader on the most effective strategies for this population. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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