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61.
Carney complex (CNC) is characterized by lentiginosis and myxomatosis together with a variety of endocrine, neural crest-derived, and other tumors, including primary pigmented nodular adrenocortical disease (PPNAD). PPNAD is characterized by lipofuscin-containing, autonomously functioning, cortisol-producing nodules surrounded by mostly atrophic adrenocortical and normal adrenomedullary tissue. The nature and origin of the tumors, including the myxomas and PPNAD, are unclear. In this study, seven paraffin-embedded PPNAD tumors, one skin myxoma, and two cell lines (one myxoma and one PPNAD) established from patients with CNC were stained with antisera for synaptophysin (SYN), neuron-specific enolase, chromogranin A, tyrosine hydroxylase, and the neural cell adhesion molecule (NCAM). In addition, one PPNAD specimen and one myxoma were analyzed by electron microscopy. The results showed that chromogranin A and tyrosine hydroxylase stained adrenomedullary tissue, but not the PPNAD nodules or the extranodular adrenal cortex. SYN, neuron-specific enolase, and NCAM also stained the medulla. PPNAD nodules and the PPNAD cell line, but not the extranodular adrenal cortex, stained intensely for SYN. The myxoma cell line, but not normal fibroblasts, stained for SYN and NCAM. Ultrastructural analysis of a PPNAD tumor and a skin myxoma revealed a well developed rough endoplasmic reticulum, prominent mitochondria, and vesicle-like structures dispersed throughout the cytoplasm. We conclude that immunostaining for SYN, a marker protein for neuroendocrine cells, clearly distinguishes PPNAD nodules from surrounding adrenocortical tissue and can be helpful in the detection of small nodules in apparently unaffected cortex. The cells of a cutaneous myxoma were also stained positive by two of the three neuroendocrine markers. Finally, both PPNAD and myxoma cells demonstrated ultrastructural features suggestive of neuroendocrine properties. These results support the previously suggested hypothesis that the genetic mechanism leading to CNC involves genes with a neuroendocrine role.  相似文献   
62.
A group of 99 babies born in hospital and subsequently transferred to the special care unit were examined for the presence of candidas orally. The rate of isolation rose from 6% neonatally to 53% on day 14 of life. Among infants who did not harbour the organisms when discharged from hospital, colonization rapidly took place so that 79% did so at 4 weeks of age, after which the rate fell to 50% at one year of age. The low incidence of clinical candidosis suggests that in these babies as in other groups C. albicans is normally a harmless commensal.  相似文献   
63.
Eight cases of dermatomyositis in children admitted to Scottish hospitals between 1962 and 1972 have been reviewed. 6 of the 8 were currently in complete remission. In the other 2 cases the disease remained active in 1 and 1 had died of cardiac failure 6 years after the onset of disease. 5 had developed extensive soft tissue calcification for which 2 were treated with ethanehydroxydiphosphonate, one showing definite improvement and the other no change. All had been treated with corticosteroids and two in addition had had cytotoxic agents (methotrexate or cyclophosphamide). The overal prognosis had probably been improved by the use of corticosteroids but not by the cytotoxic drugs. Only one of the patients was incapacitated by residual contractures or calcinosis.  相似文献   
64.
We compared serum levels of total alkaline phosphatase (TAP) and bone-specific alkaline phosphatase (BAP) as determined by three different assays (lectin affinity electrophoresis, immunoradiometric assay, enzyme-linked immunosorbent assay) in subjects aged 5–20 years suffering from X-linked hypophosphatemic rickets ( n = 14), chronic renal failure ( n = 10) and chronic cholestatic liver disease ( n = 16). Results were compared to controls of the same age and were expressed as standard deviation scores (SDS). TAP correlated significantly with BAP ( r > 0.9 for each assay; p <0.001) in controls. In children with cholestatic diseases, TAP (median SDS + 2.0) was elevated, but BAP, as measured by the electrophoretic assay, was within the reference range for most patients (median SDS: -0.4; p = 0.003 for the difference between the median SDS of TAP and BAP). In contrast, results for BAP as determined by the two immunoassays were not significantly different from TAP in any of the three patient groups ( p > 0.05 in each group for both assays). In this study, the two immunoassays did not have a detectable advantage over lectin affinity electrophoresis in the determination of BAP.  相似文献   
65.
Eight patients with Fanconi's anemia were given cyclophosphamide alone (seven patients) or combined with procarbazine and antithymocyte globulin (one patient) followed by marrow grafts from HLA-identical siblings. All patients had engraftment. Seven developed acute and three chronic graft-versus-host disease (GVHD). Three patients died with GVHD and infectious complications (days 19, 56, and 82) and one with an intracerebral hemorrhage (day 540). Four patients are surviving 647- 3435 days after grafting, two are well, and two have chronic GVHD that is improving. These results show that Fanconi's anemia can be treated successfully by allogeneic marrow transplantation.  相似文献   
66.
Canis familiaris allergen 1 (Can f 1) and Canis familiaris allergen 2 (Can f 2) are the two major allergens present in dog dander extracts. We now report the isolation of cDNAs encoding both proteins and present their nucleotide and deduced amino acid sequences. Can f 1, produced by tongue epithelial tissue, has homology with the von Ebner's gland (VEG) protein, a salivary protein not previously thought to have allergenic properties. Can f 2, produced by tongue and parotid gland, has homology with mouse urinary protein (MUP), a known allergen. Both VEG protein and MUP are members of the lipocalin family of small ligand-binding proteins. Recombinant forms of Can f 1 and Can f 2 were produced and tested for immunoglobulin E (IgE) reactivity. Among dog-allergic subjects, 45% had IgE directed exclusively to rCan f 1, and 25% had IgE to both rCan f 1 and rCan f 2. In addition, both recombinant proteins were able to cross-link IgE and elicit histamine release from peripheral blood leucocytes in vitro. These findings confirm that Can f 1 and Can f 2 are major and minor dog allergens, respectively, and demonstrate that recombinant forms of dog allergens retain at least some IgE-binding epitopes.  相似文献   
67.
68.

Background

Epidemiologic and health impact studies of fine particulate matter with diameter < 2.5 μm (PM2.5) are limited by the lack of monitoring data, especially in developing countries. Satellite observations offer valuable global information about PM2.5 concentrations.

Objective

In this study, we developed a technique for estimating surface PM2.5 concentrations from satellite observations.

Methods

We mapped global ground-level PM2.5 concentrations using total column aerosol optical depth (AOD) from the MODIS (Moderate Resolution Imaging Spectroradiometer) and MISR (Multiangle Imaging Spectroradiometer) satellite instruments and coincident aerosol vertical profiles from the GEOS-Chem global chemical transport model.

Results

We determined that global estimates of long-term average (1 January 2001 to 31 December 2006) PM2.5 concentrations at approximately 10 km × 10 km resolution indicate a global population-weighted geometric mean PM2.5 concentration of 20 μg/m3. The World Health Organization Air Quality PM2.5 Interim Target-1 (35 μg/m3 annual average) is exceeded over central and eastern Asia for 38% and for 50% of the population, respectively. Annual mean PM2.5 concentrations exceed 80 μg/m3 over eastern China. Our evaluation of the satellite-derived estimate with ground-based in situ measurements indicates significant spatial agreement with North American measurements (r = 0.77; slope = 1.07; n = 1057) and with noncoincident measurements elsewhere (r = 0.83; slope = 0.86; n = 244). The 1 SD of uncertainty in the satellite-derived PM2.5 is 25%, which is inferred from the AOD retrieval and from aerosol vertical profile errors and sampling. The global population-weighted mean uncertainty is 6.7 μg/m3.

Conclusions

Satellite-derived total-column AOD, when combined with a chemical transport model, provides estimates of global long-term average PM2.5 concentrations.  相似文献   
69.
This study examined the effects of appraisal of sexual stimuli on sexual arousal in women with superficial dyspareunia (n = 50) and sexually functional women (n = 25). To elicit different appraisals of an erotic film fragment, participants received an instruction prior to viewing it, with a focus on genital pain or on sexual enjoyment. A neutral instruction served as a control condition. Assignment to instruction condition was randomized. Genital arousal (vaginal pulse amplitude) and self-report ratings of affect and genital sensations were obtained in response to the erotic stimulus. As predicted, appraisal of the erotic stimulus affected genital responding, albeit marginally significant. Follow-up tests indicated that women who received the genital pain instruction responded with marginally significant lower genital arousal levels than women who received the sexual enjoyment instruction (d = 0.67). A significant instruction effect for negative affect was found, signifying that negative affect ratings were highest after the genital pain instruction and lowest after the sexual enjoyment instruction (d = 0.80). A marginally significant group by instruction interaction effect was observed for positive affect, indicating that women with dyspareunia reported significantly less positive affect than controls after the sexual enjoyment instruction (d = 1.48). Whereas women with dyspareunia reported overall marginally significant more negative affect than controls (d = 0.48), there were no differences in genital responsiveness between groups. These results provided preliminary evidence for the modulatory effects of appraisal of sexual stimuli on subsequent genital responding and affect in women with and without sexual complaints.  相似文献   
70.

Background  

Influenza surveillance systems provide important and timely information to health service providers on trends in the circulation of influenza virus and other upper respiratory tract infections. Online dissemination of surveillance data is useful for risk communication to health care professionals, the media and the general public. We reviewed national influenza surveillance websites from around the world to describe the main features of surveillance data dissemination.  相似文献   
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