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11.
We studied the histological and ultrastructural changes in the liver and alterations in the liver test results before, during, and after treatment with human interferon- from five patients with hepatitis B e antigen-positive chronic active hepatitis. A daily dose of 3×106 to 6×106 units of interferon- was given intravenously for four weeks. The total index of periportal and portal inflammation, intralobular degeneration, and focal necrosis before treatment was decreased significantly six months after treatment (P<0.05). Ultrastructurally, the structure of endoplasmic reticulum was irregularly shaped or fragmentally decreased during treatment, but these disappeared six or 12 months after treatment. Glycogen particles diminished greatly during treatment. The alanine aminotransferase concentrations in these patients increased during treatment. Serum albumin and cholinesterase levels decreased significantly at the fourth week of treatment (P<0.01) and at the third day (P<0.01) to the second week (P<0.05) of treatment, respectively. These results suggest that interferon- injures endoplasmic reticulum and glycogen areas and damages the cholinesterase activity in the early stage of treatment and protein synthesis in patients with hepatitis B e antigen-positive chronic active hepatitis.  相似文献   
12.
We recorded neurons extracellularly in layers II/III, IV, and V of the hindpaw representation of primary somatosensory cortex in anesthetized rats and studied laminar features of receptive fields (RFs) and representational maps. On average, RFs were smallest in layer IV and largest in layer V; however, for individual penetrations we found substantial deviations from this rule. Within the hindpaw representation, a distinct rostrocaudal gradient of RF size was present in all layers. While layer V RFs were generally largest independent of this gradient, layer IV RFs recorded caudally representing the proximal portions of the paw were larger than layer II/III RFs recorded rostrally representing the digits. The individual scatter of the locations of RFs across laminar groups was in the range of several millimeters, corresponding to about 25% of the average RF diameter. The cutaneous representations of the hindpaw in extragranular layers were confined to the areal extent defined by responsive sites in layer IV. Comparison between RFs determined quantitatively and by handplotting showed a reliable correspondence. Repeated measurements of RFs revealed spontaneous fluctuations of RF size of no more than 5% of the initial condition over an observation period of several hours. The topography and variability of cortical maps of the hindpaw representation were studied with a quantitative interpolation method taking into account the geometric centers of RFs and the corresponding cortical recording sites. On average, the overall topography in terms of preservation of neighborhood relations was present in all layers, although some individual maps showed severe distortions of topography. Factors contributing to map variability were overall position of the representation on the cortical surface, internal topography and spatial extent. Interindividual variability of map layout was always highest in the digit representations. Local topographic orderliness was lowest in layer V, but comparable in layers II/III and IV. Within layer IV, the lowest orderliness was observed in the digit representations. Our data emphasize a substantial variability of RF size, overlap and position across layers and within layers. At the level of representational maps, we found a similar degree of variability that often co-varied across layers, with little evidence for significant layer specificity. Laminar differences are likely to arise from the specific input-output pattern, layer-specific cell types and the connectivity between different layers. Our findings emphasizing similarities in the variability across layers support the notion of tightly coupled columnar interactions between different layers.  相似文献   
13.
An autopsy case of systemic histiocytosis with excessive deposition of K-type light chain crystals was reported in a 58 year-old man who had consistently showed K-type light chain paraproteinemia, Bence Jones proteinuria and hypogammaglobulinemia for about 10 years until his death. However, no bony destruction was found by repeated X-ray examinations. At autopsy, extensive hyperplasia of crystal-storing histiocytes was observed in the bone marrow, spleen, liver, lymph nodes, interstitial tissues of visceral organs and loose connective tissues. In the bone marrow and some other tissues, mild proliferation of plasmocytoid cells containing small crystals were found, Histochemically the crystals positively stained with various methods for amino acids and proteins, especially with Weigerts'method for fibrin Ultra-structurally intralysosomal crystal deposition was confirmed in the storage histiocytes and derivation of the crystals from Golgi's sacculi in the plasmocytoid cells was suggested. Biochemically the crystals were regarded as mainly consisting of dimers of a variable half of light chain immunoglobulin and immunochemically and immunohistochemically reacted to anti- type light chain serum. Such a generalized storage histiocytosis may be secondarily induced by immunoglobulin synthesized in plasmocytoid cells.  相似文献   
14.
As a design for a biodegradable functional polymer, compositionally homogeneous poly[(sodium acrylate)-co-(vinyl alcohol)] [P(SA-co-VA)], containing varying amounts of vinyl alcohol groups as biodegradable segments were prepared and their biodegradability and builder performance in detergent formulations were analyzed with respect to the successive vinyl alcohol length. It was found that the acrylate copolymers having more than 80 mol-% vinyl alcohol content showed biodegradability. That is, P(SA-co-VA) having a vinyl alcohol chain length of more than about 5–6 is cleaved by PVA-degrading microbes. This indicates that the vinyl alcohol blocks, which act as biodegradable segments, should be incorporated into the polymer chain in such a manner that they are accepted as substrates by the PVA-degrading enzymes.  相似文献   
15.
We report the results of reduced-intensity unrelated cord blood transplantation (RI-UCBT) in patients with advanced malignant lymphoma. Twenty patients (median age, 46.5 years; range, 27-66 years) underwent RI-UCBT with a preparative regimen consisting of fludarabine 125 mg/m2 , melphalan 80 mg/m 2 , and 4 Gy of total body irradiation. The median infused total cell dose was 2.75 x 10(7)/kg (range, 2.3-3.4 x 10(7)/kg). Graft-versus-host disease (GVHD) prophylaxis was composed of cyclosporine or tacrolimus alone. Fifteen patients achieved primary neutrophil engraftment after a median of 20 days. Eight patients developed grade II to IV acute GVHD, and 2 developed chronic GVHD. Of the 16 patients with evaluable disease, 10 achieved a complete response. Primary disease recurred in 1 patient, and transplant-related mortality within 100 days occurred in 8 of 20 patients. The estimated 1-year probability of progression-free survival was 50%. These data suggest that RI-UCBT is a feasible option for patients with refractory lymphoma who lack an HLA-matched donor.  相似文献   
16.
A total of 236 fecal specimens collected from infants and children with gastroenteritis in Maizuru city, Japan from July 2002 to June 2003, were tested for the presence of rotaviruses, noroviruses, sapoviruses, astroviruses, and adenoviruses by RT-PCR, PAGE, RPHA, and latex agglutination methods. Among diarrheal viruses detected, group A rotavirus was the most prevalent (32.2%; 76 of 236) followed by norovirus GII (21.2%; 50 of 236), group C rotavirus (10.2%; 24 of 236), adenovirus (3.8%; 9 of 236), sapovirus (2.5%; 6 of 236), astrovirus (1.3%; 3 of 236), and norovirus GI (0.8%; 2 of 236), respectively. It is noteworthy that group C rotavirus infection was apparently confined only within the period of 5 months (December 2002 through April 2003). This pattern of infection implied that the outbreak of group C rotavirus in these patients, which was the first outbreak of gastroenteritis attributed to group C rotavirus in Maizuru city. Moreover, about half (12 of 24) of group C rotavirus infected cases were confined to infants and young children less than 3 years old. Another interesting feature of the study was the demonstration of the mixed infections with group C rotavirus and group A rotavirus, as well as group C rotavirus and norovirus GII in 20.8% (5 of 24) and 8.3% (2 of 24), respectively. This is the first report of gastroenteritis associated with the mixed infections with group C rotavirus and other viral enteropathogens such as norovirus. The results indicate that group C rotavirus could infect not only older children and adults but also infants and young children under 3 years old.  相似文献   
17.
Conserved tRNA gene cluster in starfish mitochondrial DNA   总被引:10,自引:0,他引:10  
Summary Partial sequencing of mtDNA from four long-diverged species of starfish reveals the existence of a conserved cluster of 13 tRNA genes, organized in a manner similar to that of the tRNA cluster of sea urchin mtDNA, but located at a position distant from the presumed replication origin. These findings suggest that a clustered organization of tRNA genes may have been present in the ancestral mitochondrial genome, and raise the possibility that tRNAs may have catalyzed the dispersal rather than the accumulation of the genes which encode them.  相似文献   
18.
This paper describes a disposable flow cytometer that uses an air-liquid two-phase microfluidic system to produce a focused high-speed liquid sample stream of particles and cells. The susceptibility of thin liquid columns to instabilities may suggest that focusing of sample liquids with streams of air would be difficult. The design of channel geometry, control of flow rates, and use of appropriate surface chemistries on the channel walls, however, enabled the generation of thin (15–100 m) and partially bounded sample streams that were stable and suitable for rapid cell analysis. Using an inverted epi-fluorescence microscope with a photo-multiplier tube, we demonstrated that the system is capable of counting the number of beads and C2C12 myoblast cells. The effects of different flow rates and surface chemistries of the channel walls on the air-liquid two-phase flows were characterized using optical and confocal microscopy. Use of air instead of liquids as a sheath fluid eliminates the need for large sheath liquid reservoirs, and reduces the volume and weight requirements. The low manufacturing cost and high volumetric efficiency make the air-sheath flow cytometer attractive for use as a stand-alone device or as an integrated component of bio-artificial hybrid microsystems.  相似文献   
19.
The effect of enterostatin injection into the rat lateral hypothalamic area (LHA) on serotonin and dopamine releases in extracellular space was investigated by in vivo microdialysis technique. The primary focus being to understand whether a small amount of enterostatin crossing the blood-brain barrier correlates with activity changes in serotonergic and dopaminergic nervous systems or not. We found a significant elevation in serotonin release in the LHA. The enterostatin perfusion also induced a smaller but significant increase in dopamine level than serotonin one. This result suggests that enterostatin plays some sort of role in the control of feeding of fat through the control serotonergic and dopaminergic satiety mechanism.  相似文献   
20.
Serum carcinoembryonic antigen (CEA), immunosuppressive acidic protein (IAP) and C-reactive protein (CRP) levels were measured in patients with adult T cell leukemia (ATL) in order to clarify their significance in this disease. Mean (+/- SD) serum CEA levels in 11 patients with acute ATL (3.1 +/- 1.3 ng/ml) and 7 patients with smoldering ATL (3.1 +/- 0.5 ng/ml) were significantly higher than in sera of 222 healthy controls (2.4 +/- 1.3 ng/ml). However, the levels in 7 patients with chronic ATL and healthy controls showed no differences. On the other hand, mean (+/- SD) serum IAP levels in patients with acute ATL (928 +/- 395 micrograms/ml), chronic ATL (487 +/- 125 micrograms/ml) and smoldering ATL (429 +/- 90 micrograms/ml) were significantly higher than in sera of healthy controls (359 +/- 103 micrograms/ml). However, the levels in patients with smoldering ATL and healthy controls showed no differences. Serum IAP levels in crisis in chronic and smoldering ATL were similar to those in patients with acute ATL. 85% of ATL patients with IAP levels above 500 micrograms/ml had CRP levels above 1+. Serum CEA, IAP and CRP levels were serially measured in a number of patients. Serum IAP and CRP levels reflected each patient's clinical course more than serum CEA levels. Overall the simultaneous measurements of serum CEA, IAP and CRP levels revealed a potential usefulness for determination of ATL subtype, and serum IAP and CRP levels may provide a way to evaluate the effectiveness of chemotherapy.  相似文献   
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