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Effect of feeding 0.5% curcumin diet or 1% cholesterol diet was examined in albino rats rendered diabetic with streptozotocin injection. Diabetic rats maintained on curcumin diet for 8 weeks excreted comparatively less amounts of albumin, urea, creatinine and inorganic phosphorus. Urinary excretion of the electrolytes sodium and potassium were also significantly lowered under curcumin treatment. Dietary curcumin also partially reversed the abnormalities in plasma albumin, urea, creatine and inorganic phosphorus in diabetic animals. On the other hand, glucose excretion or the fasting sugar level was unaffected by dietary curcumin and so also the body weights were not improved to any significant extent. Diabetic rats fed curcumin diet had a lowered relative liver weight at the end of the study compared to other diabetic groups. Diabetic rats fed a curcumin diet also showed lowered lipid peroxidation in plasma and urine when compared to other diabetic groups. The extent of lipid peroxidation on the other hand, was still higher in cholesterol fed diabetic groups compared to diabetic rats fed with control diet. Thus, the study reveals that curcumin feeding improves the metabolic status in diabetic conditions, despite no effect on hyperglycemic status or the body weights. The mechanism by which curcumin improves this situation is probably by virtue of its hypocholesterolemic influence, antioxidant nature and free radical scavenging property.  相似文献   
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Using the polymerase chain reaction with degenerate oligonucleotides derived from conserved motifs within the catalytic kinase domain of protein tyrosine kinases, and RNA extracted from embryonic stem cells, sequences that encode a segment of the kinase domain of several potentially novel receptor tyrosine kinases (RTKs) have been identified. One of these was selected for further study because in Northern analysis it hybridized to RNA from multipotential hematopoietic cell lines, but not from lines representative of lineage-committed cells. A cDNA for this receptor, designated developmental tyrosine kinase (DTK), was isolated and encodes a protein with structural similarities to AXL. Together these receptors form a new class of RTK. DTK is expressed in a number of human leukemic cell lines, and in the blasts of 6 of 11 patients with acute myeloid leukemia (AML) analyzed. The structure of DTK suggests that it may function as a cell adhesion molecule, and mediate cell-to-cell or cell-matrix interactions between hematopoietic cells and their respective microenvironments.  相似文献   
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Increasingly, health care workers are being threatened and physically attacked by the people they are trying to help. What can physicians do to protect themselves and their coworkers?  相似文献   
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OBJECTIVE: To describe the occurrence and management of sexual dysfunction induced by selective serotonin-reuptake inhibitors (SSRIs), to provide an overview of sexual dysfunction, reports of SSRI-induced sexual dysfunction, and management strategies. DATA SOURCES: Information was retrieved from a MEDLINE English-literature search from January 1986 to July 1998 and by review of references. Indexing terms included sexual dysfunction, antidepressants, selective serotonergic reuptake inhibitors, fluoxetine, sertraline, paroxetine, fluvoxamine, clomipramine, buspirone, nefazodone, bupropion, cyproheptadine, amantadine, yohimbine, and central nervous system stimulants. STUDY SELECTION: There are no controlled studies describing SSRI-induced sexual dysfunction or its management. Twenty-one studies are presented, including 2 open-label studies, 12 case series, and 7 case reports. SSRI-induced sexual dysfunction is described with fluoxetine, paroxetine, sertraline, and fluvoxamine for 3-24 weeks of therapy. DATA SYNTHESIS: Data were organized according to the pharmacologic agent used in the management of SSRI dysfunction, target population, SSRI implicated, type of sexual dysfunction, experimental design, and treatment response. Data were extracted from methodology and results sections of reports. Methodologic flaws included failure to account for gender differences, omission of SSRI dose and duration, and use of concomitant drugs. CONCLUSIONS: The frequency of reports suggests that SSRI-induced dysfunction is a common adverse effect; controlled studies are necessary to determine prevalence. Most reports have occurred with fluoxetine, but this phenomenon may be related to its widespread use. Further study is needed to evaluate baseline sexual function, to define target populations, and to compare SSRIs in inducing sexual dysfunction. Serotonin antagonists and dopamine agonists have been used most often to treat SSRI-induced dysfunction and have generally been effective, but controlled studies are also needed.  相似文献   
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The photosynthetic light-harvesting complex, peridinin-chlorophyll a-protein, was isolated from several marine dinoflagellates including Glenodinium sp. by Sephadex and ion-exchange chromatography. The carotenoid (peridinin)-chlorophyll a ratio in the complex is estimated to be 4:1. The fluorescence excitation spectrum of the complex indicates that energy absorbed by the carotenoid is transferred to the chlorophyll a molecule with 100% efficiency. Fluorescence lifetime measurements indicate that the energy transfer is much faster than fluorescence emission from chlorophyll a. The four peridinin molecules within the complex appear to form two allowed exciton bands which split the main absorption band of the carotenoid into two circular dichronic bands (with negative ellipticity band at 538 nm and positive band at 463 nm in the case of peridinin-chlorophyl a-protein complex from Glenodinium sp.). The fluorescence polarization of chlorophyll a in the complex at 200 K is about 0.1 in both circular dichroic excitation bands of the carotenoid chromophore. From these circular dichroic and fluorescence polarization data, a possible molecular arrangement of the four peridinin and chlorophyll molecules has been deduced for the complex. The structure of the complex deduced is also consistent with the magnitude of the exciton spliting (ca. greater than 3000 cm-1) at the intermolecular distance in the dimer pair of peridinin (ca. 12 A). This structural feature accounts for the efficient light-harvesting process of dinoflagellates as the exciton interaction lengthens the lifetime of peridinin (radiative) and the complex topology increases the energy transfer probability. The complex is, therefore, a useful molecular model for elucidating the mechanism and efficiency of solar energy conversion in vivo as well as in vitro.  相似文献   
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Expression of alpha-D-mannosidase in man-hamster somatic cell hybrids   总被引:1,自引:0,他引:1  
Two types of alpha-D-mannosidase isozymes are present in human white blood cells, human diploid fibroblasts, and HeLa cells. One of these (the S isozyme) constitutes the major alpha-D-mannosidase of the human cells, has a pH optimum of 4.4, and is associated with lysosomes. The other (the F isozyme) is most active at pH 6, is acid labile, and is located in the soluble portion of the cytoplasm. The expression of human lysosomal alpha-D-mannosidase was examined in man-hamster hybrid clones, and was found to be concordant with that of phosphohexose isomerase in 54 of 55 primary clones. A locus specifying human lysosomal alpha-D-mannosidase has therfore been assigned to chromosome 19.  相似文献   
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