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71.
Fresh rat and mouse lymphoid cells have been labelled by stable linkage with tetramethylrhodamine isothiocyanate (TMRITC). A change in intensity, either an increase or decrease of the fluorescent emission of the cells, detected by microfluorimetry, was induced by mitogen stimulation or the mixed lymphocyte reaction. The change in fluorescence was observed within 3 h of mitogen stimulation and within 0.5 h in the mixed lymphocyte test. These early cellular responses were detectable consistently whether the labelling was done before or after mitogen stimulation; post-labelling only was studied in the mixed lymphocyte reaction. The method should provide a time-saving practical procedure for early detection of the lymphoid cell responses and would readily lend itself to flow cytofluorimetry for possible routine diagnostic use.  相似文献   
72.
Niemann-Pick disease type C is a clinically heterogeneous storage disorder with an unknown primary metabolic defect. We have undertaken somatic cell hybridisation experiments using skin fibroblast strains from 12 patients representing a wide clinical spectrum. Preliminary experiments using filipin staining of free cholesterol as a marker for complementation indicated the existence of one major group (group alpha) and one minor group (group beta) represented by one mutant strain. Subsequent experiments in which sphingomyelinase activity was measured as a marker for complementation using five mutant strains showing activity consistently < 40% control levels confirmed the existence of the second group.  相似文献   
73.
We describe the first case in which a diagnostic rise in titers of antibody to formalinized Legionella pneumophila serogroup 1 yolk sac antigen was shown to be caused by a cross-reaction between L. pneumophila and another organism, Citrobacter freundii.  相似文献   
74.
Synergy between sulfamethoxazole (SMZ) and trimethoprim (TMP) was predicted by a two-plate agar dilution breakpoint MIC system. Comparison of the results of this new system with those of the disk diffusion system (P.M. Waterworth, Postgrad. Med. J. Suppl. 45:21-27, 1969) after tests with 1,518 Enterobacteriaceae isolates showed an overall correlation of 99.8%, a sensitivity of 99.7%, and a specificity of 100%. The method involves spot inoculation of 10(3) organisms onto each of two plates, one containing 160 micrograms of SMZ per ml and the other 8 micrograms of TMP per ml (in Oxoid IsoSensitest medium with 3% agar supplemented with 7% saponin-lysed horse blood), and then incubation overnight at 37 degrees C in air. All but three organisms for which SMZ-TMP was found to be synergistic by disk testing were inhibited on both plates. Three isolates of Proteus mirabilis, which failed to correlate with disk testing by this new system, all showed SMZ MICs of 1,000 micrograms/ml. The SMZ-TMP combination was falsely predicted to be nonsynergistic against these three organisms. There were no false synergy predictions by the breakpoint MIC system. Laboratories should report susceptibility to the SMZ-TMP combination only when there is synergy between the constituents. This simple, reliable agar dilution technique enables laboratories to accurately report synergy between SMZ and TMP.  相似文献   
75.
Cancer diagnosis affects the psychological well-being of both patients and their partners, and effective coping has been suggested to be a conjoint process of mutual support. Ninety-four married women with early stage cancer and their partners were randomly assigned to couples-based coping training (CanCOPE), individual coping training for the woman, or a medical education control. Couples' observed support communication and self-reported psychological distress, coping effort, and sexual adjustment were assessed at diagnosis, after cancer surgery, and at 6- and 12-month follow-ups. CanCOPE produced significant improvements in couples' supportive communication, reduced psychological distress and coping effort, and improved sexual adjustment. Training in couples rather than individual coping was more effective in facilitating adaptation to cancer.  相似文献   
76.
D V Pow  J F Morris  A R Ward 《Neuroscience》1992,50(3):503-512
In homozygous Brattleboro rats a frame-shift mutation in the vasopressin gene prevents secretion of vasopressin by magnocellular neurosecretory neurons and thus causes diabetes insipidus. Whereas most "vasopressin" neurons in Brattleboro homozygotes apparently lack vasopressin and its associated neurophysin and glycopeptide, some isolated cells overcome the mutation and "revert" to producing readily detectable amounts of vasopressin. We describe here two morphologically and immunocytochemically distinct subsets of such "revertant" cells. One subset contain, in their rough endoplasmic reticulum cisterns, electron-dense aggregates immunoreactive for vasopressin, for parts of oxytocin-neurophysin, and for CP14 (a peptide with a sequence deduced from the mutated precursor), but not for vasopressin-associated glycopeptide ("glycopeptide") or vasopressin-neurophysin. In Brattleboro heterozygotes, which have one mutant and one normal copy of the vasopressin gene, morphologically similar revertant cells exist; the aggregates in the rough endoplasmic reticulum of these cells do not immuno-label for CP14, but the cells do produce 160-nm neurosecretory granules immunoreactive for vasopressin, vasopressin-neurophysin and glycopeptide. In Brattleboro homozygotes, the second, more abundant subset of neurons which recover vasopressin immunoreactivity also express vasopressin-associated glycopeptide and CP14 but not oxytocin-neurophysin; both glycopeptide and CP14 are restricted to the rough endoplasmic reticulum but do not form aggregates. We conclude that two different somatic repairs of the Brattleboro mutation can occur. We propose that, in aggregate-containing neurons, exons B and C have been exchanged between the vasopressin and oxytocin genes; glycopeptide-immunoreactive neurons have either undergone mismatch repair or exchanged exon B.  相似文献   
77.
We report the isolation of Legionella pneumophila serogroup 4 from synovial tissue obtained from an 80-year-old female with chronic swelling of her right metacarpophalangeal joint. Synovial tissue infections caused by L. pneumophila are rare. Interestingly, this isolate was recovered from chocolate agar after 5 days of incubation.  相似文献   
78.
The most frequent aneuploidies in newborns involve the autosomes 13, 18 and 21 as well as both sex chromosomes. Fluorescence in situ hybridization readily allows the detection of numerical chromosomal aberrations throughout all stages of the cell cycle. Using a multicolor fluorescence in situ hybridization approach based on combinatorial probe labeling and digital imaging microscopy we demonstrate the simultaneous visualization of probe sets specific for chromosomes 13, 18, 21, X and Y. This approach enables one to evaluate aberrations of multiple chromosomes in a single hybridization experiment using metaphase chromosomes and interphase nuclei from a variety of cell types, including lymphocytes and amniocytes.  相似文献   
79.
Ischemia (4-hour) followed by reperfusion (4-hour) of rat hind limbs results in local injury as well as remote (lung) injury. It has recently been shown that injury in this model is neutrophil- and cytokine-dependent and requires the beta 2 integrin adhesion molecules CD11a/CD18 and CD11b/CD18. The role of selectins in events leading to injury (as determined by leakage of albumin and by hemorrhage) was assessed either through the use of blocking antibodies to L-, E- or P-selectins or by the use of oligosaccharides that are reactive with selectins. Lung injury was found to be L- and E-selectin-dependent. When the ischemia and reperfusion times were reduced, lung injury was also found to be P-selectin dependent. In the case of hind limb injury involving the crural muscle mass, injury was L-selectin-dependent but independent of requirements for P- and E-selectin. Injury in both organs was blocked by the infusion of sialylated Lewis pentasaccharide, whereas sialyl-N-acetyllactosamine pentasaccharide failed to protect against injury. In general, when selectin-blocking approaches were protective, there were parallel reductions in tissue content of myeloperoxidase. These data underscore the role of selectins in ischemia-reperfusion injury and suggest that selectin requirements may vary with the vascular bed under study.  相似文献   
80.
The distribution of carbonic anhydrase in the exocrine pancreas of the rat has been examined during the first 3 weeks after duct ligation. The normal pattern of positive reaction in ducts, centroacinar cells and capillaries changed, by the end of the first week, to one in which all the cells in the dilated ducts showed the enzyme. This situation persisted through the third week. By electron microscopy, the enzyme was found on the apical membranes of ductular, centroacinar and acinar cells, as well as on the surface membranes of the modified cells seen at 1 week. The significance of these findings with respect to function and cell origin is discussed.  相似文献   
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