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11.
An ultrastructural study was carried out on 25 lymphocyte-trapping cells selected from tissue cultures of human axillary lymph nodes. The trapping cells contained several hundred intravacuolar lymphocytes, most of which showed degenerative changes. The principal findings are: (a) a braod spectrum of lymphocyte degeneration; (b) a consistent pattern of lymphocyte degeneration beginning with perinuclear vacuoles and ending with breakdown of the nuclear envelope; (c) the viable lymphocytes tended to be located in a juxtanuclear region; (d) a lysosomal relationship was suggested for lymphocyte degeneration but not for lymphocyte trapping; and (e) degeneration of the trapping cell, or lymphocytes associated with other cells, was not observed. The sequence of degenerative changes differs from those reported for several classes of lymphocytocidal agents. There were no morphologic properties of the trapping cell which served to identify it more specifically. The findings, together with previous time-lapse film observations, warrant further investigation of the hypothesis that lymphocytocidal lymphocyte trapping may be involved in the control of lymphocyte populations.  相似文献   
12.
Chronic hypertrophic gastritis in a 7-year-old Boxer dog is described. This gastritis resembles Menetrier's disease in man. The dog was emaciated, lethargic, vomiting and had a poor appetite over a 4-month period. There was anaemia, and the blood smear was characterized by hypochromasia, strong anisoplania and striking poikilocytosis. There was a protein loss and at a later stage of the disease, a hypoalbuminaemia. On gastroscopic examination the plicae gastricae were numerous and strongly marked; moreover, they were granulated with numerous small haemorrhages. Radiographically, the stomach had a marked folding, primarily at the greater curvature. The passage of contrast medium from the stomach into the duodenum was strongly retarded. The pathological findings included macroscopical folding caused by local gland cell hyperplasia in the body as well as the pylorus, foveolar hyperplasia and, in the fundus and in the corpus near the greater curvature, folding of the muscularis mucosae and the submucosa. A superficial gastritis was found particularly in the fundus and corpus, whereas the pyloric antrum showed a more diffuse inflammation.  相似文献   
13.
A rapid increase of predominantly unconjugated bilirubin in the blood -- which was not due to haemolysis -- was observed in 38 of 60 patients who had taken an overdose of paracetamol. Studies in the rat given an overdose of the drug showed that within 24 hours there was a striking reduction in the activity of bilirubin glucuronyl-transferase and the content of cytochrome P.450 in the liver. It is suggested that such early damage of the hepatic endoplasmic reticulum contributes to the hyperbilirubinaemia of paracetamol poisoning.  相似文献   
14.
The fine structure and cellular associations of the large pigment cells (LPC's) of the compound eye of the house fly were studied with high voltage and conventional electron microscopy. Depending on the sector of the compound eye, the facets are either rectangular or hexagonal. The underside of each facet has indentations exactly aligned with those on top into which inserts an angulated sleeve of LPC's. Under the rectangular lens facet 6 or 8 small compact (in cross section) LPC's join four elongate LPC's. Clusters of compact cells alternate in this ring with elongate ones. Compact cells compress together and become quadrangular (in cross section) several microns below their insertion into the lens and form "building block" corners while elongate cells form "side rails" for the rectangular type of distal pseudocone enclosure. Beneath hexagonal facets all LPC's are rather elongate with out corner cells. In both facet types LPC's enclose the pseudocone for a longitudinal distance of 4 mum and then are displaced as bordering cells by a sleeve of two corneal pigment cells (CPC's), each of which encloses half of the proximal pseudocone. For the following 6 mum of longitudinal distance these concentric sleeves of CPC's and LPC's form a double layer around the pseudocone. At about 10 mum below lens base the two sleeves separate; LPC's become attenuated and extend cable-like to the basement membrane and CPC's enclose the proximal pseudocone, Semper cells and distal retinula. The junction between lens and LPC's has critical structural value in that (1) this is the sole anchorage to the lens by the lengthy remainder of the ommatidium, and (2) LPC's enclose the semiliquid pseudocone in the most distal portion of the pseudocone. In addition to vertical support, the LPC's send out numerous lateral processes that make structural contact among themselves, with the corneal pigment cells and the photoreceptor cells. The structural features of this array are discussed relative to possible physiological roles.  相似文献   
15.
A galactosidase immunosorbent test for human immunoglobulin E   总被引:1,自引:0,他引:1  
We report here the development of a galactosidase-immunosorbent test (GIST) for immunoglobulin E (IgE) antibodies in which the amount of galactosidase adsorbed to a cellulose disc is a single valued function of IgE concentration in human serum. Rabbit anti-IgE immunoglobulin insolubilized on cellulose discs is incubated sequentially with human serum, sheep anti-IgE serum, and a covalent conjugate of rabbit antisheep immunoglobulin with the enzyme beta-D-galactoside galactohydrolase (E.C.) 3.2.1.23). Colorimetric assay of enzyme conjugate adsorbed to discs permits quantitation of 1.0 to 25 ng of IgE per test. Concentrations of IgE in 48 sera as measured by the GIST gave a linear correlation coefficient of 0.97 with IgE concentrations as determined by radioimmunoassay. Preliminary studies indicate that the GIST makes possible nonisotopic measurement of ragweed-specific IgE antibiotics in human serum. The GIST for IgE is simple to perform and requires neither short-lived radioisotopes, expensive scintillation detection equipment, nor scarce, purified IgE.  相似文献   
16.
Fourteen women with amenorrhea-galactorrhea were treated with bromo-ergocryptine. Serum prolactin hPRL, hLH, hFSH, estradiol 17-beta (E2), and progesterone values were determined before and during treatment. No consistent pretreatment hormonal pattern was found. During treatment hPRL levels fell in 13 of 14 patients, and E2 rose in 12 of 14 patients. Levels of hLH became normal, and amounts of hFSH did not change. Galactorrhea lessened in all cases and ceased in 11. Menses resumed in 11 patients and 3 women became pregnant. Cessation of galactorrhea and resumption of menses occurred irrespective of initial hPRL or hLH levels. It is suggested that improvement of galactorrhea and resumption of menses in some patients with normal hPRL values are the result of increased serum E2 levels and may be due to a direct action of bromo-ergocryptine on the ovary. Bromo-ergocryptine may also be effective in treatment of amenorrhea, unassociated with galactorrhea or elevated hPRL levels.  相似文献   
17.
The effect of sodium taurocholate in stepwise increasing infusion rates, 0.3 to 9.6 mumoles per min per kg, on the biliary excretion rate of iodipamide was investigated in 6 dogs (10 experiments) with complete bile diversion under general anesthesia. Iodipamide was administered intravenously with an initial priming dose of 33 mumoles per kg followed by a constant infusion of 1.3 mumoles per min per kg. Although the bile flow continuously increased with an increasing taurocholate dose, the iodipamide excretion rate reached a plateau with a 0.6 mumoles per min per kg of taurcholate infusion, which was 20% higher than with the lowest taurocholate dose. With a taurocholate dose over 2.4 mumoles per min per kg, a significant decrease in the iodipamide rate was found, amounting to 22% of its maximum value with the largest taurocholate dose. The bile iodipamide concentration was already at its maximum with the lowest taurocholate dose, and it decreased with an increasing taurocholate dose. Since the bile iodipamide concentration is probably the most important determinant in clinical cholangiography, low bile salt plasma levels should result in the best radiographic visualization of the biliary tree.  相似文献   
18.
Fasting plasma free amino acids were determined in 54 convalescent malnourished infants: seven infants while consuming a diet based on isolated soybean protein, containing 4.0% to 5.3% of dietary metabolizable energy (calories) as protein (A), 20 at 6.4% to 6.7% protein calories (B), 23 at 6.4% to 6.7% protein calories with added DL-methionine (C), and four with 8.0% to 12.3% protein calories (D). There were no differences in total amino acid concentration (TAA) among the four groups; the molar fraction of essential amino acids (EAA:TAA) was lower for group A; there were no differences among the four groups in Lys:EAA or 1/2 cystine:EAA ratios or in Met concentration. Met:EAA was higher in C than B, with considerable overlap of individual values. In 10 of 13 infants who were represented in both B and C, Met concentration and Met:EAA ratio were higher in group C. Fasting plasma AA levels are not consistently reliable for field or clinical assessment of dietary Met adequacy. Fasting and postprandial (3- and 4-hour) plasma AA were determined in 29 infants: in 12 the preceding diet and the test meal were both Met-deficient with less than 6.7% protein calories (E), in five the preceding diet was milk-based but the test meal was Met-deficient at less than 6.7% (F), in five the preceding diet and test meal were based on isolated soybean protein at less than 6.7% with DL-Met added (G), and in seven the test meal was soy-based with greater than 9.0% protein calories (H). Plasma Met concentration and Met:EAA fell significantly at 3 and 4 hours in groups E and F, but not in groups G and H, suggesting that a postprandial fall in Met:EAA ratio can be used to identify dietary Met deficiency in field situations.  相似文献   
19.
A method for affinity chromatography of plasma and platelet factor XIII has been developed, based on known structural characteristics of these molecules. Plasma factor XIII is composed of a and b subunits which are held together by noncovalent interactions; platelet factor XIII has only a subunits. a subunit contains free sulfhydryl groups, while in b subunit all the cystines form disulfide bonds. The affinity gel is an organomercurial agarose with p-chloromercuribenzoate as the reactive group. Both the zymogen and activated forms of a subunit reversibly bind to the ligand by forming covalent mercaptide bonds and are eluted by reducing agents. b subunit does not bind to the affinity gel and is held to it only through interaction with a subunit. Affinity chromatography can be used to purify plasma and platelet factor XIII and to study interactions of the subunits. Experiments on the affinity chromatography of purified plasma factor XIII in several stages of activation agree with earlier observations that activation is a two-step procedure in which b subunit is not quantitatively released from the complex until the final stage of activation by Ca2+.  相似文献   
20.
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