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141.
Ataxia telangiectasia (A-T) is an autosomal recessive disorder in which patients show an unusual predisposition to malignant disease, including T-cell chronic lymphocytic leukaemia. We report here the steady growth over 5 years of a complex, cytogenetically abnormal clone of T lymphocytes in an A-T patient who was subsequently found to have an OKT3/OKT8 chronic lymphocytic leukaemia. The tumour cells at diagnosis had clearly evolved from a pre-existing, cytogenetically abnormal T-cell clone which contained an inv(14) chromosomal inversion alone.  相似文献   
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Subchronic exposure of male rats to the nephrotoxin 2,2,4-trimethylpentane (TMP) causes an accumulation of protein droplets in the epithelial cells of the renal cortex. Experimental evidence suggests that these droplets contain alpha 2u-globulin, a low-molecular-weight protein found specifically in the urine of male rats. It has been proposed that aldehyde metabolites of TMP form Schiff base adducts with the lysine groups of alpha 2u-globulin and thereby inhibit renal lysosomal processing of the protein. Accordingly, the ability of TMP and its metabolites to covalently bind to alpha 2u-globulin was examined. As a model, a [14C] formaldehyde-alpha 2u-globulin Schiff base was formed. This protein adduct was stabilized by reduction with cyanoborohydride and could be identified by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). Protein analysis by SDS-PAGE demonstrated that hepatocytes isolated from male Fischer-344 rats produced significant quantities of alpha 2u-globulin in culture, whereas hepatocytes from female rats did not. A 15-hr exposure of metabolically competent, primary cultures of male rat hepatocytes to [14C] TMP (0.1 and 0.5%, v/v), followed by reduction with cyanoborohydride, dialysis, and analysis with SDS-PAGE, revealed no evidence of radiolabeled alpha 2u-globulin. When [14C]TMP was administered to an adult male Fischer-344 rat (300 mg/kg, ig) 22, 16, and 10 hr before sacrifice, 16% of the administered radioactivity was eliminated in the urine as TMP metabolites. Analysis as above showed no TMP-derived radioactivity in fractions containing alpha 2u-globulin from liver, blood, kidney cortex, or urine. The absence of a detectable covalent interaction between TMP and alpha 2u-globulin following in vitro or in vivo exposure suggests that a TMP-alpha 2u-globulin adduct is not responsible for the excessive formation of protein droplets in the renal cortex of exposed male rats.  相似文献   
144.
Gurney  JW; Bates  FT 《Radiology》1989,173(1):27-31
A rare pulmonary manifestation of the acquired immunodeficiency syndrome or intravenous (IV) drug abuse is upper lobe cystic disease--pneumatoceles in Pneumocystis carinii pneumonia (PCP) and bullous emphysema in IV drug abuse. Because these disorders overlap, the radiographic findings in 56 patients were compared. During a 12-month period, 16 patients less than 40 years of age were found to have bullous emphysema; the 10 who were IV drug abusers constituted group 1. In the same time period, 40 patients with PCP were encountered; the eight (20%) who had or developed pneumatoceles constituted group 2. In both groups, the conventional radiographic manifestations of upper lobe cystic disease were similar. Eight patients underwent computed tomography of the chest. In five patients with bullous disease, the distribution of the bullous lesions was peripheral, with sparing of the central portions of the lungs. In contrast, PCP pneumatoceles in three patients were dispersed throughout the lung parenchyma.  相似文献   
145.
Generating research in mental health nursing   总被引:1,自引:0,他引:1  
This paper explores a number of areas for research development in mental health nursing in the United Kingdom. Several potential areas are identified: historical research, policy related research, the role of mental health nurse as a provider of a therapeutic milieu, as therapist and as teacher. Academic centres are identified in mental health nursing research and a plea is made for the preservation of valuable archive data being lost as mental hospitals are closed. Nurse leaders in mental health nursing are encouraged to make particular provision for research activity.  相似文献   
146.
Background: Females have worse outcome than do males after coronary artery bypass grafting; however, gender effects on length of stay (LOS) outcomes, such as duration of intubation or intensive care unit (ICU) LOS, have not been evaluated previously. The authors hypothesized that adjustment for pertinent preoperative covariates would eliminate any significant effect of gender on duration of intubation, LOS in the ICU after extubation, total ICU LOS, postoperative (exclusive of ICU) LOS, or total postoperative LOS.

Methods: Patients undergoing elective or urgent primary coronary artery bypass grafting surgery at 51 academic health centers in 1995 and 1997 were studied. Unique multivariable statistical models were developed for duration of intubation, ICU LOS after extubation, total ICU LOS, and postoperative (exclusive of ICU and total) LOS to test for independent associations with gender. Preoperative but not intraoperative or postoperative variables were included in the model. P >= 0.01 was considered significant.

Results: All LOSs were of significantly longer duration in females than in males in both the 1995 (n = 1,064) and 1997 (n = 910) data collections. After covariate adjustment, female sex remained associated with significantly longer duration ICU LOS and total postoperative LOS in both the 1995 (female:male ratios 1.30:1 and 1.13:1, respectively) and the 1997 (female:male ratios 1.19:1 and 1.12:1, respectively) data sets. After covariate adjustment, duration of intubation and ICU LOS after extubation were of significantly longer duration in women than men in 1995 (female:male ratios 1.22:1 and 1.39:1, respectively), but the differences were not significant in 1997.  相似文献   

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148.
To determine whether concentrations of diethylaminoethanol (DEAE) and procaine below those that reduce the amplitude of action potentials might alter the excitability of brain cells, a single microelectrode intracellular recording technique was used to measure firing threshold and action potential amplitude of pyramidal cells in rat hippocampal slices. At low concentrations of both DEAE (less than or equal to 5 mM) and procaine (less than or equal to 0.5 mM), firing threshold was significantly increased (P less than 0.01), whereas action potential spike amplitude was minimally altered. At higher concentrations, both drugs significantly decreased action potential spike amplitude (P less than 0.025) as well as increased firing threshold (P less than 0.001). Diethylaminoethanol tended to increase threshold relatively more than procaine, when drug concentrations that similarly reduced action potential amplitude were compared. All actions of DEAE and procaine were reversible. Inhibition of action potentials by DEAE and procaine was clearly concentration-dependent (P less than or equal to 0.015). Diethylaminoethanol effects on threshold were marginally concentration-dependent (P = 0.08); procaine did not demonstrate clear concentration-dependent effects (P = 0.33) over the concentrations tested in this study. These similar actions of procaine and DEAE on brain cells suggest a mechanism by which intravenous local anesthetics may contribute to the general anesthetic state. Moreover, it appears possible that procaine metabolism and DEAE accumulation may underlie the prolonged effects sometimes seen after intravenous procaine administration.  相似文献   
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