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71.
Two patients with chronic myelogenous leukemia and new variant Philadelphia chromosome translocations are reported. In one case, a 41-year-old male, a 10;22 translocation was found in all bone marrow cells examined. Furthermore, the Y chromosome was missing in 90% of the analyzed metaphase cells. In the second patient, a 22-year-old male, all the marrow cells contained a complex rearrangement involving chromosomes No. 2, 9, and 22. 相似文献
72.
Human lymphocytes were cultured for two cell cycles in the presence of bromodeoxyuridine (BrdU), and the resulting metaphase chromosomes were first stained with quinacrine mustard (QM) and then, immediately afterwards, with Hoechst 33258, without any intermediate destaining. Both Q-banding patterns and sister chromatid differential staining were photographed subsequently on the same metaphase using two different filter blocks of the fluorescence microscope. 相似文献
73.
J Blomfield J A Simson A M Martinez J R Martinez 《Experimental and molecular pathology》1983,38(2):170-182
Rat submandibular gland tissue pieces were stimulated in vitro for 30 min with a beta-adrenergic agent or a cyclic AMP analog to stimulate protein secretion, or with alpha-adrenergic or cholinergic agents or a Ca2+ ionophore to stimulate fluid secretion. Acinar cells were examined by transmission electron microscopy. In control tissue, acinar cells showed little evidence of secretory activity. The Golgi apparatus was sparse and was associated with a few small, immature secretory granules with fine fibrillar contents. Following secretory granule discharge stimulated by isoproterenol or dibutyryl cyclic AMP, acinar cells were constricted, and had extensive basolateral membrane folding and tightly packed rough endoplasmic reticulum. Golgi complexes were prominent and had multiple small granules with filamentous contents. After stimulation of fluid secretion by alpha-adrenergic agents (epinephrine, phenylephrine), or cholinergic agents (acetylcholine, carbachol, pilocarpine), or a Ca2+ ionophore (A23187), the Golgi apparatus had compact concave cisternae enclosing aggregates of tubulovesicles. Acinar cells were distended, basolateral membranes were expanded, and rough endoplasmic reticulum was dilated and vesiculated. 相似文献
74.
The acute effects of the deposition of papain in the lungs of 4-month-old rabbits have been investigated with an amount not sufficient to cause emphysematous changes. During the first 2 days of in vivo deposition when hemorrhaging and inflammation occur, the total amounts of collagen and elastin in the lung, into which the papain had been instilled, did not change but the concentrations of collagen and elastin decreased 20 and 25% respectively. The rates of synthesis of collagen and other proteins doubled. By 4 weeks, collagen and elastin concentrations returned to, or were slightly above, control levels. The histological appearance and mean linear intercepts of lung sections and the compliance curves of excised lungs of the treated animals were similar to controls by 2 weeks after papain administration. The rabbit lung thus appears able to repair mild injury due to proteolytic enzymes. 相似文献
75.
76.
J G Hall M S Birbeck D Robertson J Peppard E Orlans 《Journal of immunological methods》1978,19(4):351-359
Lymph-borne immunoblasts were fixed in dilute glutaraldehyde and then treated with saponin. This treatment made most parts of the cells permeable to ferritin, so that anti-immunoglobulin (Ig) antibodies which had been conjugated to horse radish peroxidase (HRP) had no difficulty in gaining access to Ig which thus could be demonstrated at an ultrastructural level. Best results were obtained by fixing the cells in 0.1% glutaraldehyde for 7 min and then treating them with a 1% solution of saponin for 100 min at 55 degrees C before exposing them to the Ig-HRP conjugate. The method yielded reproducible results and although it causes a small amount of ultrastructural damage, it may be of value in detecting a variety of intracellular antigens. 相似文献
77.
Identification of the major structural proteins of two BALB/c myeloma C-type viruses. 总被引:2,自引:0,他引:2
We have analyzed the structural proteins of the C-type viruses produced by cloned lines of the MOPC-21 and FLOPC-1 BALB/c murine myelomas. These viruses, designated MO21-MuMAV and FL1-MuMAV, respectively, have been shown to be composed of proteins with approximate molecular weights of 90,000, 75,000, 17,000, 12,000, and 10,000 daltons. In addition, these viruses contain a “doublet” with molecular weights of approximately 30,000 daltons. The 90,000- and 75,000-dalton proteins are glycosylated. The p30 “doublet” as well as the NB-ecotropism is retained upon subsequent virus cloning in SC-1 cells, passage through NIH-3T3, or BALB/3T3 cells, or microtiter plate cloning of SC-1 cells replicating cloned virus. The two cloned MuMAVs appeared to possess the p30 proteins of the endogenous BALB/c N- and B-tropic viruses described by Hopkins and co-workers (N. Hopkins, J. Schindler, and R. Hynes, 1977, J. Virol.21, 309–318; J. Schindler, R. Hynes, and N. Hopkins, 1977, J. Virol. 23, 700–707). Subsequent tryptic peptide analysis of the myeloma virus p30 proteins demonstrated that these proteins share extensive homology with, but not identity to, the two prototype BALB/c ecotropic endogenous virus p30 proteins. 相似文献
78.
When HANA protein of HVJ (Sendai virus) was denatured by dithiothreitol treatment, concanavalin A added to the system or influenza virus hemagglutinin reconstituted with treated HVJ-envelope to form hybrid by SM-2 dialysis method could not replace a role of HANA for hemolysis. Binding of the treated samples to erythrocytes was restored by them, however. Thus, a hypothesis is proposed that intactness of not only F but also HANA protein of HVJ is required for envelope-cell fusion, in other words, HANA protein of HVJ may play some positive role other than binding in the process of the virus-induced hemolysis. 相似文献
79.
F Hecht A Grix B K Hecht C Berger H Bixenman S Szucs D O'Keeffe H J Finberg 《Cancer Genetics and Cytogenetics》1984,11(1):107-111
A fetal tumor was suspected at 31 weeks of gestation. The occurrence of polyhydramnios led to an ultrasound examination, which revealed deformation of the fetal head, face, eye, and neck. This was confirmed by computerized tomography. Amniocentesis yielded cells with an inverted duplication of chromosome #1. This abnormality of chromosome #1 marked the malignant teratoma cells in the amniotic fluid. Cytogenetic analysis of tumor tissue and of normal tissue obtained postnatally confirmed that the abnormality of chromosome #1 observed in amniotic fluid cells was confined to the tumor. The constitutional karyotype was normal. To our knowledge, this is the first report of the direct chromosomal detection of malignancy before birth. 相似文献
80.
Narendra G Mehta 《Medical hypotheses》1977,3(2):63-70
The evidence that the acute phase glycoproteins of plasma are synthesized by the liver parenchymal cells is critically examined, and is found to be inconclusive. Some evidence is cited which favors the reticulo-endothelial system (RES) in general, and Kupffer cells in particular, as the site of synthesis of these proteins: 1. The entire RES contains non-glycogenic periodic acid Schiff-positive substances. 2. The diseases which affect glycoprotein levels are also known to affect the function of the RES. 3. When the animal is subjected to stress, the RES function is initially depressed and then stimulated. A similar biphasic behavior is shown by plasma glycoprotein levels. 4. Adrenal cortico-steriods are the major regulators of the RES function and of the synthesis of acute phase proteins. Moreover, both are stimulated at low concentrations, and depressed at high concentrations of the hormone. Some of the glycoproteins of the acute phase (prothrombin, the third component of complement, haptoglobin, transferrin and ceruloplasmin) have defense-related functions. The others seem to participate in phenomena like detoxification, promotion of phagocytosis, wound healing, prevention of tissue injury by lysosomal enzymes, prevention of trauma and recovery from inflammation. It is proposed that the acute phase proteins, together with antibodies, form major components of the defense system, and the RES attempts to deal with injury by mobilization of increased amounts of these substances. 相似文献