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101.
A 6-year-old white female was found to have an adenoid cystic carcinoma originating in a lacrimal gland. Eighteen months following diagnosis, the tumor recurred. Conservative surgery has been the sole mode of therapy. To date, after four operations and quadrimenstral imaging surveillance, there is no sign of disease progression. Our purpose is to record the unusual occurrence of an adenoid cystic carcinoma of the lacrimal gland in a child. An interim report, 32 months after diagnosis, is presented.  相似文献   
102.
Ten axenic isolates of Trichomonas vaginalis were subcutaneously injected to the BALB/c mice in order to assess their pathogenicity by means of so-called "mouse assay" method. All the isolates revealed neutral and acid proteinase activities both in their lysates and in culture media, but the specific activities of both proteinases in the severely pathogenic group were significantly higher than the mildly pathogenic group (p < 0.05). In the SDS-PAGE system in which the electrophoretic gels contained 0.4% gelatin as the substrate, five different banding patterns of trichomonal proteinases were detected, and the patterns were closely related with the pathogenicity of the isolates of T. vaginalis. All five bands might be regarded as cysteine proteinases group in the inhibitor assays. The cytotoxicity of the lysates of T. vaginalis to the target Chinese hamster ovarian (CHO) cell line was also significantly different according to the pathogenicity of the isolates, and generally lower in the lysates treated with cysteine proteinase inhibitors than in the control lysates. In summarizing the results, it might be considered that the proteinases of T. vaginalis showing five electrophoretic banding patterns are closely related with the pathogenicity and cytotoxicity of the isolates of T. vaginalis.  相似文献   
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BACKGROUND: Hyaluronan is an endogenous polysaccharide whose clearance from the plasma is predominantly by liver sinusoidal cells and is sinusoidal flow dependent. This study was designed to determine if a change in serum hyaluronan might reliably reflect short-term drug-induced changes in sinusoidal perfusion. METHODS: Hemodynamic changes following an oral dose of ketanserin were compared with changes in serum hyaluronan levels in 12 patients with alcoholic liver disease and portal hypertension. Indices determined comprised heart rate, mean arterial pressure (MAP), cardiac output (CO), systemic vascular resistance, hepatic venous pressure gradient (HVPG), indocyanine green (ICG) clearance and extraction, and total hepatic blood flow. Measurements were made in a basal state 1 hour after ketanserin ingestion and expressed as a ratio of values post- to pre-ketanserin administration. RESULTS: Ketanserin had variable effects comprising both increases and decreases in all indices. On univariate and multivariate analysis, changes in serum hyaluronan concentration (1.05 +/- 0.13, mean +/- SD) significantly correlated with only one index: changes in ICG clearance (0.93 +/- 0.17, r = -0.65, P = 0.02). CONCLUSIONS: Changes in serum hyaluronan levels reflect short-term drug-induced changes in sinusoidal perfusion in patients with alcoholic liver disease and portal hypertension. Serial measurement of serum hyaluronan levels may offer a simple method of screening vasoactive drugs for their short-term effects on sinusoidal perfusion.  相似文献   
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The ELM erythroleukemia is novel in that long-term survival of leukemic cells in culture (ELM-D cells) is dependent on contact with a bone marrow-derived stromal feeder cell layer. However, a number of stroma-independent (ELM-I) mutants that vary in their ability to differentiate in vitro in response to erythropoietin and interleukin-3 have been derived. We have attempted to define the genetic changes responsible for these different phenotypes. At the p53 locus in the primary leukemic cells, one copy of the gene has been lost whereas the other contains an 18-bp depletion, implicating its mutation as an early step in the development of the leukemia. Changes in ets gene expression have also been found. The Fli-1 gene region is rearranged in the primary tumor because of the insertion of a retrovirus inserted upstream of one Fli-1 allele, but this does not result in Fli-1 gene activation in any of the ELM-D or ELM-I cell lines except one. It seems significant that this line is the only one to have lost the ability to differentiate in response to erythropoietin. In addition, up-regulation of erg is associated with stromal cell-independent growth, since all ELM-I mutants have moderate levels of erg mRNA, whereas only low or undetectable levels are found in primary leukemic cells in vivo or in ELM-D cells in vitro. This up-regulation of erg mRNA seems to be important for stromal cell-independent growth, since ELM-D cells show elevated expression of the erg gene after separation from stromal cells. This seems to be made permanent in ELM-I mutants, since they do not down-regulate erg mRNA when grown in contact with stromal cells. We therefore propose that ets family members regulate both the survival and differentiation of erythroid cells.  相似文献   
107.
The objective of this study was to determine the effect of long-term administration of a growth hormone (GH)-releasing factor analog (GRFa) and(or) thyrotropin-releasing hormone (TRH) on growth, feed efficiency, carcass characteristics, and blood hormones and metabolites in beef heifers. Crossbred heifers (n = 48; 345.9 +/- 2.8 kg) were divided into four equal groups: control (vehicle), 1 microgram of GRFa (human GRF 1-29 analog).kg BW-1.d-1, 1 microgram of TRH.kg BW-1.d-1, or GRFa + TRH. Daily s.c. injections continued for 86 d. Blood samples were collected from half of the heifers after injection on d 1, 36, and 78. On d 89, all heifers were slaughtered. Treatments did not affect (P > .05) ADG but GRFa + TRH decreased (P < .05) ADFI relative to all other treatments. Feed conversion efficiency tended (P < .10) to be improved in the groups given GRFa alone or TRH alone. Treatment with GRFa and(or) TRH did not affect carcass weight, dressing percentage, conformation score, backfat thickness, or weights of liver, kidneys, pituitary, and ovaries. The GRFa + TRH treatment reduced (P < .05) fat score and increased (P < .05) longissimus muscle area relative to other treatments. The GRFa treatments reduced (P < .05) the weight and fat percentage of the mammary gland and increased (P < .05) heart weight. Treatment with TRH alone failed to stimulate GH on d 1, 36, and 78. Treatment with GRFa alone increased (P < .05) GH above controls on d 36, whereas GRFa + TRH increased (P < .05) GH on d 1, 36, and 78. Treatment with GRFa alone increased (P < .05) IGF-I only on d 1, whereas GRFa + TRH was without effect on all days. Across sampling days, treatments had little effect on blood concentrations of insulin, triiodothyronine, nonesterified fatty acids, urea nitrogen, and glucose. The GRFa alone and GRFa + TRH decreased (P < .05) and TRH alone increased (P < .05) thyroxine concentrations. In conclusion, with the dose and administration regimen used, GRFa and(or) TRH yielded small but positive improvements in animal performance.  相似文献   
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Algal blooms in the spread and persistence of cholera   总被引:1,自引:0,他引:1  
Cholera has been long associated with the seasonality of coastal algal blooms off Bangladesh. Using fluorescent antibody (FA) techniques, microbiologists have now identified a viable, non-cultivable form of Vibrio cholerae in a wide range of marine life, including cyanobacteria (Anabaena variabilis), diatoms (Skeletonema costatum), phaeophytes (Ascophyllum nodosum), in copepod molts, and in freshwater vascular aquatic plants (water hyacinths and duckweed). In unfavourable conditions V. cholerae assumes spore-like forms; with proper nutrients, pH and temperature, it reverts to a readily transmissible and infectious state. Nitrates and phosphates in sewage and fertilizers cause eutrophication, and scientists report an increase in intensity, duration and shifts in the biodiversity of algal blooms in many coastal, brackish and fresh waters worldwide. V. cholerae has been isolated from phyto- and zooplankton in marine and fresh waters near Lima, Peru. V. cholera 01, biotype El Tor, serotype Inaba, may have arrived in the Americas in the bilge of a Chinese freighter. There, in the abundant coastal sea life along the Latin American Pacific coast, nourished by the Humboldt current and eutrophication, it found a reservoir for surviving unfavourable conditions. It is hypothesized that the algae and Vibrio populations grew exponentially; consumed by fish, mollusks and crustacea, a heavy 'inoculum' of carriers infected with V. cholerae was generated and transported into multiple coastal communities.  相似文献   
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