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961.
A case is described of acute cerebellar symptoms as the presenting features of Epstein-Barr virus (EBV) infection. Cerebellar encephalitis is discussed with particular reference to EBV infection.  相似文献   
962.
IL-1 alpha and IL-1 beta bind to receptors termed the type I and type II IL-1 receptors. The type I IL-1 receptor is responsible for specific signaling, while the type II IL-1 receptor functions as a nonsignaling decoy receptor. To determine the effect of a defect in IL-1-mediated signaling, mice have been produced with a genetically disrupted type I IL-1 receptor gene. Mice lacking type I IL-1 receptors are of normal vigor and exhibit no overt phenotype. B cells from type I IL-1R-/- mice activated in vitro with anti-IgM do not proliferate in response to IL-1, but do so in response to IL-4. Injection of murine IL-1 alpha does not induce detectable serum IL-6 levels in type I IL-1R-/- mice, but equivalent levels are produced in response to LPS. Type I IL-1R-/- mice have normal serum Ig levels and generate equivalent primary and secondary Ab responses as wild-type mice. In response to LPS, acute phase protein mRNA induction are equivalent in type I IL-1R-/- and wild-type mice. Type I IL-1R-/- mice do not differ from control mice in susceptibility to either a lethal challenge with D-galactosamine plus LPS or high dose LPS. Interestingly, ICE-/-/type I IL-1R-/- double mutant mice are resistant to high dose LPS. Type I IL-1R-/- mice backcrossed to the C57BL/6 background were as equally resistant as wild-type mice to Listeria monocytogenes.  相似文献   
963.
Progesterone receptor (PR) messenger RNA (mRNA) is concentrated in neurons of the preoptic area and other regions of the rat hypothalamus where it is colocalized with the estrogen receptor and regulated by changes in the steroid hormonal milieu. To date, little is known about the regulation of PR mRNA by estrogens and whether antiestrogenic compounds are capable of modulating its expression. The present studies used in situ hybridization to ascertain the time course of PR mRNA regulation in the medial preoptic nucleus by 17beta-estradiol, determine the effective dose required to elicit a response, and compare the efficacy of 17beta-estradiol with a variety of estrogenic or antiestrogenic compounds. The first series of studies revealed that the treatment of ovariectomized rats with 17beta-estradiol resulted in an increase in PR expression within 2 h, after which it remained elevated until 10 h postinjection and then returned to baseline levels. When ovariectomized rats were injected with 25-1000 ng/kg of 17beta-estradiol and euthanized 6 h later, a dose-dependent increase in the level of PR mRNA was observed, with a maximal response at 1000 ng/kg and an EC50 of 93.5 ng/kg. Subsequent studies evaluated the efficacy of a variety of estrogenic and antiestrogenic compounds in the rat preoptic nucleus. 17Beta-estradiol, diethylstilbestrol, and 17alpha-estradiol all significantly increased the level of PR mRNA, although the degree of induction varied with each compound. The injection of tamoxifen, raloxifene, toremifene, droloxifene, clomiphene, GW 5638, or ICI 182,780 had no significant estrogenic effect on PR gene expression at the dose evaluated. In contrast, when tamoxifen or raloxifene, but not ICI 182,780, was administered in the antagonist mode, a significant dose-related decrease in the estradiol-induced level of PR mRNA was seen in the preoptic area. The results of these studies clearly demonstrate that PR mRNA expression in the rat preoptic area is rapidly stimulated by a small dose of 17beta-estradiol. Moreover, the present report has also shown that the estrogenic nature of compounds such as tamoxifen, raloxifene, toremifene, droloxifene, clomiphene, and GW 5638 cannot be predicted by their activity in peripheral tissues. Together, the results of these studies provide important information about the central activity of estrogens and provide evidence for their tissue-specifc actions in the rat.  相似文献   
964.
Biochemical and immunochemical data from the present investigation reveal the existence of a p85/p110 phosphoinositide 3-kinase (PI 3-kinase) in rat liver nuclei. 32P-Labeling of membrane phosphoinositides by incubating intact nuclei with [gamma-32P]ATP results in the formation of [32P]phosphatidyl-inositol 3,4, 5-trisphosphate [PtdIns(3,4,5)P3], accompanied by small quantities of [32P]phosphatidylinositol 3-phosphate [PtdIns(3)P]. Studies with subnuclear fractions indicate that the PI 3-kinase is not confined to nuclear membranes. The nuclear soluble fraction also contains PI 3-kinase and an array of inositide-metabolizing enzymes, including phospholipase C (PLC), phosphoinositide phosphatase, and diacylglycerol (DAG) kinase. As a result, exposure of phosphatidylinositol 4,5-bisphosphate [PtdIns(4,5)P2] to the nuclear extract in the presence of [gamma-32P]ATP generates a series of 32P-labeled D-3 phosphoinositides and phosphatidic acid (PA) in an interdependent manner. On the basis of the immunological reactivity and kinetic behavior, the nuclear PI 3-kinase is analogous, if not identical, to PI 3-kinase alpha, and constitutes about 5% of the total PI 3-kinase in the cell. Moreover, we test the premise that nuclear PI 3-kinase may, in part, be regulated through the control of substrate availability by PtdIns(4,5)P2-binding proteins. Effect of CapG, a nuclear actin-regulatory protein, on PI 3-kinase activity is examined in view of its unique Ca2+-dependent PtdIns(4, 5)P2-binding capability. In vitro data show that the CapG-mediated inhibition of nuclear PI 3-kinase is prompted by PKC phosphorylation of CapG and elevated [Ca2+]. This CapG-dependent regulation provides a plausible link between nuclear PLC and PI 3-kinase pathways for cross-communications. Taken together, these findings provide definite data concerning the presence of an autonomous PI 3-kinase cycle in rat liver nuclei. The nuclear location of PI 3-kinase may lead to a better understanding regarding its functional role in transducing signals from the plasma membrane to the nucleus in response to diverse physiological stimuli.  相似文献   
965.
A novel member of the low density lipoprotein receptor (LDLR) gene family has been identified and characterized. This gene, termed LDL receptor-related protein 6 (LRP6), encodes a transmembrane protein which has 71% identity and is structurally similar to the protein encoded by LRP5, a proposed candidate gene for type 1 diabetes located on human chromosome 11q13. LRP6 maps to human chromosome 12p11-p13. Mouse Lrp6 encodes a protein that has 98% identity to human LRP6 and maps to chromosome 6. Unlike other members of the LDLR family, LRP6 and LRP5 display a unique pattern of four epidermal growth factor (EGF) and three LDLR repeats in the extracellular domain. The cytoplasmic domain of LRP6 is not similar to other members of the LDLR family, while comparison with LRP5 reveals proline-rich motifs that may mediate protein-protein interactions. Thus, it is likely that LRP6 and LRP5 comprise a new class of the LDLR family.  相似文献   
966.
OBJECTIVE: The purpose of this report is to show that Dacron (DuPont, Wilmington, DE) cuffs retained in breasts after the removal of Hickman catheters may result in complications requiring radiographic evaluation for subsequent management. We also describe potential complications, including infection, associated with a retained cuff and changes after the removal of a retained cuff. CONCLUSION: Because of the increased use of Hickman catheters for central vein access, Dacron cuffs more frequently are retained in breasts and are likely to be seen on mammograms. Radiologists need to be aware of the mammographic findings of a normal cuff, infected cuff, and the site of a surgically excised cuff.  相似文献   
967.
A commercial IgM immunoblot kit was evaluated for dengue diagnosis with a panel of serum specimens collected from patients in a dengue endemic area. The kit is not recommended for use in its present form because of its undesirable rate of false-positive results. However, by substituting internal controls with the reference positive and negative controls that are more representative of those seen in endemic areas and by modifying the positive and negative scoring criteria, sensitivity and specificity of 80.3% and 94.5%, respectively, were obtained. These results are comparable with those obtained with the IgM ELISA on specimens, most of which were obtained from outpatient health care facilities. With further technical modifications, inclusion of a visual guide to ensure scoring standardization, and a more complete elaboration of the limitations of the test, wide application of the kit in diagnostic laboratories should be possible.  相似文献   
968.
Paradoxical cerebral embolism (PCE) through a patent foramen ovale (PFO) should be considered as a cause of ischemic stroke, particularly in young patients without an alternative cause for stroke. PCE is even more important that it is potentially treatable. However, PCE remains often presumed because it rests upon the rarely demonstrated findings of a deep venous thrombosis and a thrombus lodged in the PFO. Recent studies have shown a rather low stroke recurrence rate in patients with PFO and stroke but suggest that some subgroups of patients with a higher stroke recurrence risk-exist according clinical, echocardiographical and radiological characteristics. For these subgroups, it seems that a more invasive treatment should be required. There are four therapeutic options; antiaggregants, anticoagulation, transcatheter closure of PFO, and surgical closure of PFO. However, these treatments have yet to be evaluated in clinical trials.  相似文献   
969.
The phenotype of susceptibility to malignant hyperthermia (MHS); can only be detected reliably by the in vitro caffeine-halothane contracture test (CHCT). Enhanced sensitivity of the calcium-induced calcium release mechanism is responsible for the exaggerated contracture response of skeletal muscle fibers from MHS patients to halothane and caffeine. Chlorocresol was demonstrated to be a potent activator of Ca++ release from skeletal muscle sarcoplasmic reticulum. This effect is probably mediated through action on a ryanodine sensitive Ca++ release channel known to be more sensitive in MH. We studied the effect of chlorocresol on the mechanical contracture response of skeletal muscle from patients presenting for the in vitro CHCT. Chlorocresol induces contracture response in a concentration 1/200 of that of caffeine in muscle strips from MH patients. By adding chlorocresol to the protocol of the CHCT, there is clearer discrimination between the responses of MH patients and normal subjects can be achieved.  相似文献   
970.
Heterogeneity of DNA content in multiple hepatocellular carcinomas (HCCs) was investigated by flow cytometry in 62 tumours from 26 patients who had undergone surgical treatment for multiple synchronous HCCs. Heterogeneity of DNA content was defined (a) when tumours had a different DNA ploidy pattern or (b) when the difference in the DNA index of the aneuploid clone was more than 0.1. A tumour with DNA aneuploidy was observed in 17 (66%) of the 26 patients. Heterogeneity of the DNA content was demonstrated in 12 (46%) out of 26 patients: in ten cases by definition (a) and in two cases by definition (b). Histological examination revealed that, of the 12 patients with a heterogeneous tumour DNA content, seven (58%) had a heterogeneous and the remaining five (42%) had a homogeneous type and grade of differentiation among the tumours, showing the absence of a relationship between histological heterogeneity and DNA content. The present results suggest the clinical relevance of DNA content analysis for identifying the clonal origin of multiple HCCs.  相似文献   
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