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1.
Gestational trophoblastic neoplasia (GTN) patients are treated according to the eight-variable International Federation of Gynaecology and Obstetrics (FIGO) scoring system, that aims to predict first-line single-agent chemotherapy resistance. FIGO is imperfect with one-third of low-risk patients developing disease resistance to first-line single-agent chemotherapy. We aimed to generate simplified models that improve upon FIGO. Logistic regression (LR) and multilayer perceptron (MLP) modelling (n = 4191) generated six models (M1-6). M1, all eight FIGO variables (scored data); M2, all eight FIGO variables (scored and raw data); M3, nonimaging variables (scored data); M4, nonimaging variables (scored and raw data); M5, imaging variables (scored data); and M6, pretreatment hCG (raw data) + imaging variables (scored data). Performance was compared to FIGO using true and false positive rates, positive and negative predictive values, diagnostic odds ratio, receiver operating characteristic (ROC) curves, Bland-Altman calibration plots, decision curve analysis and contingency tables. M1-6 were calibrated and outperformed FIGO on true positive rate and positive predictive value. Using LR and MLP, M1, M2 and M4 generated small improvements to the ROC curve and decision curve analysis. M3, M5 and M6 matched FIGO or performed less well. Compared to FIGO, most (excluding LR M4 and MLP M5) had significant discordance in patient classification (McNemar's test P < .05); 55-112 undertreated, 46-206 overtreated. Statistical modelling yielded only small gains over FIGO performance, arising through recategorisation of treatment-resistant patients, with a significant proportion of under/overtreatment as the available data have been used a priori to allocate primary chemotherapy. Streamlining FIGO should now be the focus.  相似文献   
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In order to study the effect of thyroid hormones on rat cerebellar granule cells, cerebellar perikarya isolated from 5-7-day-old rats were cultured in the presence of normal fetal calf serum, fetal calf serum treated with Dowex-2 ion exchange resin to remove thyroid hormones, or ion exchange-treated serum resupplemented with physiological concentrations of T4 and T3. Granule cells grown under hypothyroid conditions showed abnormal cellular aggregation, neurite fasciculation and cell survival. Cell aggregation, which may be an in vitro correlate of cerebellar granule cell migration to the internal granule layer, was reduced by over 50% under hypothyroid conditions. The rate of protein synthesis in hypothyroid cultures was stimulated by as much as 3-fold compared to thyroid hormone-containing cultures consistent with a proposal that the normal developmental pattern of diminishing protein synthesis specific activity is delayed or prevented under hypothyroid conditions. In addition ultrastructural studies revealed abnormalities in the density of cold-stable microtubules in thyroid hormone-deficient cultures. These results demonstrate that thyroid hormones can influence granule neuron behavior in the absence of Purkinje cells. Furthermore, the observed defects bear numerous similarities to documented abnormalities within the hypothyroid cerebellum, suggesting that this in vitro culture system may serve as a useful model for studying the mechanism of action of thyroid hormones on the cells of the cerebellum.  相似文献   
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Intercellular adhesion molecule‐1 (ICAM‐1) gene polymorphisms have been implicated in the susceptibility to inflammatory diseases, including multiple sclerosis and inflammatory bowel disease. The expression of both soluble and tissue ICAM‐1 is increased in Behçet’s disease (BD) but the contribution of ICAM‐1 gene polymorphisms to this disease remains unknown. Associations with BD have been reported for genes within the MHC, including HLA‐B51, TNF and MICA, but the role of non‐MHC genes in BD remains largely unexplored. We have investigated the frequency of the R/G 241 and K/E 469 ICAM‐1 gene polymorphisms in 83 patients with BD disease and 103 healthy controls, all of Palestinian and Jordanian descent, and demonstrated an association between BD and the ICAM‐1 E469 allele (Pc = 0.046, OR = 2.1). Among patients, no association was found between the presence of ocular disease and ICAM‐1 polymorphisms. While the functional correlate of this polymorphism remains unclear, this finding indicates that a genetic polymorphism in the ICAM‐1 gene domain, which is independent of the MHC, may contribute to disease.  相似文献   
5.
The distribution and intensity of alkaline phosphatase deposition in 54 patients with dermatomyositis-polymyositis (PM-DM) was analyzed by the enzyme histochemical method. Increased enzyme reactivity of endomysial capillaries was found in 28% of patients, equally distributed between adult onset PM (Group I) and PM-DM with overlap in other connective tissue diseases (Group V). Patients with high endomysial capillary reactivity (R1 larger than or equal to 60) responded poorly to steroids, had an increased incidence of rheumatoid factor, and had less fiber degeneration/necrosis in their biopsies. Twenty-two percent of patients demonstrated prominent perimysial phosphatase reactivity localized in newly formed collagen and fibroblasts. Thirty patients (55%) demonstrated significant numbers of alkaline-phosphatase-positive fibers positively correlated with increased fiber degeneration/necrosis, endomysial fibrosis, increased numbers of triglyceride-containing muscle fibers, and NADH tetrazolium reductase hyperreactivity. Minimal overlap between the three enzyme distribution patterns was found. Endomysial capillary activity probably represents endothelial alkaline phosphatase induction analogous to the pattern seen normally in lower mammals (rat, rabbit, guinea pig). Alkaline phosphatase fiber reactivity probably represents a particular phase in fiber regeneration/maturation especially after denervation and is positively correlated with an increased incidence of spontaneous fibrillation potentials in PM-DM.  相似文献   
6.
Natural killer (NK) and some T cells express killer cell immunoglobulin-like receptors (KIRs), which interact with HLA class I expressed by target cells and consequently regulate cytolytic activity. The number of KIR loci can vary and so a range of genetic profiles is observed. We have determined the KIR genetic profiles from one African (n = 62) and two South Asian (n = 108, n = 78) populations. Several of the KIRs are present at significantly different frequencies between the two major ethnic groups (eg KIR2DS4 gene frequency 0.82 African, 0.47 S Asian. Pc < 1 x 10(-6)) and this is due to uneven distribution of two KIR haplotype families 'A' and 'B'. All three populations described here displayed a greater degree of diversity of KIR genetic profiles than other populations investigated, which indicates further complexity of underlying haplotypes; in this respect we describe two individuals who appear homozygous for a large deletion including the previously ubiquitous 2DL4. We have also reanalysed three populations that we studied previously, for the presence of a KIR which is now known to be an indicator of the 'B' haplotype. South Asians had the highest overall frequencies of all KIR loci characteristic of 'B' haplotypes (Pc < 0.0001 to < 0.004). Furthermore, gene frequency independent deviances in the linkage disequilibrium were apparent between populations.  相似文献   
7.
A biopsy-proven case of scleromyxedema (papular mucinosis) with IgG lambda light chain paraproteinemia, eosinophilia and severe proximal myopathy is presented. Muscle biopsy revealed an atypical necrotizing vacuolar myopathy. Histochemical studies of cryostat sections revealed fiber necrosis, severe type II fiber atrophy, and fiber vacuolization with NADH tetrazolium reductase hyperactivity. Electron microscopy showed myocytolysis, reduplication of the basement membrane, and unit membrane-lined vacuoles negative for acid mucopolysaccharide.  相似文献   
8.
Localized amyloid tumors of the central nervous system are rare. We present the case of a 59-year-old white man with a large expansile amyloidoma at the base of the skull. To our knowledge this is the second reported case of localized amyloid tumor involving the skull.  相似文献   
9.

One barrier to optimal pain management in the neonatal intensive care unit (NICU) is how the healthcare community perceives, and therefore manages, neonatal pain. In this paper, we emphasise that healthcare professionals not only have a professional obligation to care for neonates in the NICU, but that these patients are intrinsically worthy of care. We discuss the conditions that make neonates worthy recipients of pain management by highlighting how neonates are (1) vulnerable to pain and harm, and (2) completely dependent on others for pain management. We argue for a relational account of ethical decision-making in the NICU by demonstrating how an increase in vulnerability and dependence may be experienced by the healthcare community and the neonate’s family. Finally, an ethical framework for decisions around neonatal pain management is proposed, focussing on surrogate decision-making and the importance of compassionate action through both a reflective and an affective empathy. As empathy can be highly motivating against pain, we propose that, in addition to educational programs that raise awareness and knowledge of neonatal pain and pain management, healthcare professionals must cultivate empathy in a collective manner, where all members of the NICU team, including parents, are compassionate decision-makers.

  相似文献   
10.
Kim S  Liva SM  Dalal MA  Verity MA  Voskuhl RR 《Neurology》1999,52(6):1230-1238
OBJECTIVE: To evaluate the use of estriol in the treatment of experimental autoimmune encephalomyelitis (EAE) and other cell mediated autoimmune diseases. BACKGROUND: Experimental autoimmune encephalomyelitis is a T helper 1 (Th1)-mediated autoimmune demyelinating disease that is a useful model for the study of immune responses in MS. Interestingly, both EAE and MS have been shown to be ameliorated during late pregnancy. METHODS: Estriol, progesterone, and placebo pellets were implanted in mice during the effector phase of adoptive EAE. Disease scores were compared between treatment groups, and autoantigen-specific humoral and cellular responses were examined. RESULTS: Estriol treatment reduced the severity of EAE significantly compared with placebo treatment whereas progesterone treatment had no effect. Estriol doses that induced serum estriol levels that approximated estriol levels during late pregnancy were capable of ameliorating disease. Estriol-treated EAE mice had significantly higher levels of serum antibodies of the immunoglobulin (Ig) G1 isotype specific for the autoantigen myelin basic protein (MBP). Further, MBP-specific T-lymphocyte responses from estriol-treated EAE mice were characterized by significantly increased production of the Th2 cytokine interleukin 10 (IL-10). T lymphocytes were shown to be the primary source of IL-10 within antigen-stimulated splenocyte populations. CONCLUSIONS: Estriol as a hormone involved in immune changes during pregnancy may provide a basis for the novel therapeutic use of estriol for MS and other putative Th1-mediated autoimmune diseases that improve during late pregnancy.  相似文献   
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