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101.
102.
A typical case of the D uchenne type of progressive muscular dystrophy with autopsy findings was presented. Changes in the myocardial and smooth muscle of many organs were found, and the skeletal muscles also revealed florid changes.
Histopathological examination of the skeletal muscle was made in detail through light and electron microscopic observation.  相似文献   
103.
Recently it has been reported that patients with ulcerative colitis (UC) often have thymus abnormalities, although the precise mechanisms which induce those abnormalities remain unclear. We have examined the effect of serum fractions from patients with UC and other colonic diseases on mouse thymus to clarify the possible existence of factors which have thymus growth activity. These fractions were separated from sera of patients with UC by gel filtration and anion exchange high performance liquid chromatography. In mice given UC serum fractions; (i) remarkable increases in weight and total cell number of the thymus were observed from day 4 to day 9; (ii) a significant increase in the number of peanut agglutinin (PNA)+ thymus cells was demonstrated using flow cytometry on day 9; (iii) on quantitative analysis of surface antigens the percentage of Lyt-2+ thymus cells decreased and that of L3T4+ thymus cells increased remarkably on day 13; the number of bright Thy-1.2+ cells and of dull Lyt-1+ cells increased. In contrast, the serum fractions from patients with other colonic diseases and from normal persons caused little change in mouse thymus throughout the study. The results suggest that factors fractionated from the serum of patients with UC disturb intra-thymic T cell maturation and enhance the proliferation of thymus cells.  相似文献   
104.
Chondroitin sulfate dipalmitoylphosphatidylethanolamine (CS-PE), when immobilized onto substratum, inhibited the adhesion of B16F10 mouse melanoma cells to fibronectin-coated dishes (anti-adhesion activity). CS-PE showed the most potent anti-adhesion activity for the melanoma cells among various GAG-PEs. CS-PE also inhibited the adhesion of B16F10 cells to Matrigel and the invasion of the cells into Matrigel. In the in vivo system of experimental metastasis, administration of B16F10 cells with CS-PE into C57BL/6 mice significantly inhibited lung metastasis. The inhibition degree of CS or hyaluronic acid-PE was lower than CS-PE. CS-PE administered intravenously into mice before the injection of B16F10 cells also inhibited metastasis. Pretreatment of B16F10 cells with CS-PE caused some but a lower degree of inhibition. When CS-PE was injected intravenously into mice, more binding in the lung was found than when CS was injected. CS-PE but not CS inhibited the retention in the lung of fluorochrome-labeled B16F10 cells when injected intravenously into mice. Since there was no significant effect of CS-PE on the viability and growth of B16F10 cells, the results suggest that CS-PE immobilized onto the subendothelial matrix may prevent melanoma cells from adhering to the subendothelial substrata of lung capillaries and inhibit subsequent invasion processes of metastasis.  相似文献   
105.
We report a case of primary pulmonary low-grade marginal zone B-cell lymphoma of the mucosa-associated lymphoid tissue (MALT)-type with prominent sclerosis, which morphologically resembled pulmonary hyalinizing granuloma (PHG) or inflammatory pseudotumor (IPT) of the lung. The patient, a 66-year-old Japanese female with a history of Sj?gren's syndrome and primary biliary cirrhosis, presented with a lower left lobe mass 6.8 cm in diameter. Histologically, the lesion is characterized by dense bundles of collagen with scattered plasma cells, mature small lymphocytes, and histiocytes among the collagen bundles. Only the peripheral area of the nodule contained dense lymphoplasmacytoid and histiocytoid infiltrates. A few centrocyte-like cells were obscured by the numerous plasma cells and plasmacytoid cells. In addition, lymphoepithelial lesions and colonalized lymphoid follicles were identified by immunohistochemistry alone. Although PHG and IPT are unlikely to be confused with pulmonary MALT-type lymphomas, the present case suggests that MALT-type lymphoma should be added to the list of differential diagnoses for PHG and IPT.  相似文献   
106.
The effects of biliary obstruction on the secretory activity and ultrastructure of the exocrine pancreas were studied in rats. Increased volume, protein and amylase secretion were observed in the early periods, under basal conditions and in response to cerulein-secretin stimulation. Bicarbonate concentrations in the pancreatic juice were not significantly altered during the experiments, under either basal or stimulated conditions. The wet weight of the pancreas, and the tissue protein and amylase content of the pancreas increased progressively after bile duct ligation, under basal conditions. Morphological changes were marked in the acinar cells, the most characteristic being an increase in the size and number of zymogen granules and dilatation of the Golgi cisternae. These findings demonstrate a hyperfunctional state of the acinar cells following progressive suppression of granule discharge. It is suggested that the inhibition of granule discharge from acinar cells in rats with prolonged bile duct ligation may be due to the cytotoxic effects of hyperbilirubinemia and inhibition of normal mitochondrial function.  相似文献   
107.
Genomic subtractive hybridization was used to design Prevotella nigrescens-specific primers and TaqMan probes. Based on this technique, a TaqMan real-time PCR assay was developed for quantifying four oral black-pigmented Prevotella species. The combination of real-time PCR and genomic subtractive hybridization is useful for preparing species-specific primer-probe sets for closely related species.  相似文献   
108.
Two infants (4 and 5 months of age) with a febrile episode for 3 and 5 days, respectively, developed skin rashes after the fever subsided and were diagnosed as exanthem subitum. The rash continued for 5 days followed by mild-to-moderate pigmentation. Human herpesvirus-6 and measles virus, which were confirmed by a specific immunofluorescence assay and by electron microscopy, were isolated simultaneously from blood in the acute stage of the disease but not from the convalescent stage. The titer of the herpesvirus-6 in blood was greater than that of measles. Specific serologic assays showed marked seroconversion against human herpesvirus-6 but not to measles virus. The results suggest that dual infection with human herpesvirus-6 and measles virus results in atypical exanthem subitum or modified measles with unique immunologic responses.  相似文献   
109.
Macrophage migration inhibitory (MIF-like) activity was demonstrated in the supernatant fluids from cultures of African green monkey kidney cells (BGM) infected with mumps virus or Newcastle disease virus. We could detect no such activity in noninfected cultures. The virus-induced activity reported here is not due to nonspecific cytotoxic material released by dead or dying cells, and it does not require cell replication for its production. Preliminary estimates of molecular weight by Sephadex G-100 chromatography revealed a broad band of activity associated with the 45,000 and 65,000 markers. These are significantly smaller than previously reported chemotactic substances from virus-infected cultures, and thus appear to represent different cell products. These MIF-like factors may be produced concomitantly with interferon. However, ultraviolet irradiation of appropriate duration abolishes the ability of viruses to induce substances with MIF-like activity while preserving the ability to induce interferon. This strongly suggests that interferon is not the agent responsible for the macrophage migration inhibition effect. The functional properties of these various cell products induced by virus infection suggest that they all may play a role in the response to virus infection in vivo.  相似文献   
110.
Ciliary beat frequency (CBF) was measured by video-optical microscopy in rat tracheal and distal airway ciliary cells using a slice preparation. In tracheal ciliary cells (tracheal slice), ATP or 2-methylthio ATP (MeSATP) increased CBF, which was inhibited by suramin (100 microm, an inhibitor of purinergic receptor). Ionomycin (5 microm) or thapsigargin (2 microm) increased CBF similarly. Ca2+-free solution or addition of Ni2+ (1 mm) decreased CBF gradually by approximately 25% and subsequent stimulation with ATP (10 microm) increased CBF transiently. The purinergic agonist experiments demonstrated that ATP increases CBF in tracheal ciliary cells via both P2X and P2Y receptors. ATP increased the intracellular calcium concentration ([Ca2+]i) in tracheal ciliary cells. However, in distal airway ciliary cells (lung slice), ATP did not increase CBF and [Ca2+]i, although a Ca2+-free solution decreased CBF, and ionomycin (5 microm) or thapsigargin (2 microm) increased it. Moreover, acetylcholine (100 microm) did not increase CBF in distal airway ciliary cells, although it increased CBF in tracheal ciliary cells. Terbutaline (10 microm), a selective beta2-adrenergic agonist, increased CBF in both tracheal and distal airway ciliary cells. These observations suggest that the Ca2+-mobilization mechanisms via purinergic or muscarinic receptors of the distal airway ciliary cell may be different from those of the tracheal ciliary cell. In conclusion, the CBF increase is differently regulated in the tracheal and distal airway epithelia of the rat.  相似文献   
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