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91.
R Fetni K Krabchi PE Messier CL Richer N Lemieux 《Canadian Metallurgical Quarterly》1996,63(3):454-457
A patient with mixed gonadal dysgenesis and Y isochromosomes i(Y) is described. Lymphocyte cultures from peripheral blood contained a high proportion of 45,X cells and several other cell lines with two different marker chromosomes (mars). These markers had either a monocentric (mar1) or a dicentric appearance (mar2). Following high-resolution GTG, RBG, QFQ, and CBG bandings, five cell lines were identified; 45,X/46,X,+mar1/46,X,+mar2/47,X,+mar1x2/47,X,+mar2x 2. The percentages were 66/6/26/1/1%, respectively. Chromosome banding analyses were insufficient for characterization of the markers. In situ hybridization of specific probes for the Y centromere and its short arm showed, both in fluorescence and electron microscopy (EM), two different Y rearrangements. Mar1 is an isochromosome for the short arm i(Yp) and mar2 is a dicentric which was shown by EM to be a double isochromosome Yp, inv dup i(Yp). The breakpoint producing mar1 is within the centromere and the one producing mar2 is within one of the short arms of the Y isochromosome. The findings of different cell populations in peripheral blood lymphocytes indicate the postzygotic instability of this i(Yp). 相似文献
92.
BACKGROUND: Nephrolithiasis may be an important consequence of indinavir therapy; however little has been published on the variation in incidence between different populations of patients or the possible mechanisms of calculus formation. OBJECTIVE: To examine variation in the incidence of indinavir-associated nephrolithiasis (IAN) in HIV-positive patients in relation to hemophilia and hepatitis C virus (HCV) infection. METHODS: Clinical data were abstracted retrospectively from the medical records of all adult patients treated with indinavir from September 1995 to September 1997. Occurrence of first IAN, defined as flank pain and hematuria after initiation of therapy, was analyzed in relation to hemophilia status and HCV infection. RESULTS: There were 17 episodes of IAN (22%) among 79 patients treated with indinavir. Of 10 patients with hemophilia, 50% developed IAN as compared with 17% of patients without hemophilia (P = 0.03). Median days to first IAN was 22 (range 7-110 days) for hemophiliacs and 156 (range 5-611 days) for those without hemophilia. Data for HCV status were available for 74 out of 79 patients: 10 out of 27 (37%) patients with HCV developed IAN compared with six out of 42 (14%) without HCV (P = 0.02). CONCLUSION: Overall incidence of IAN was higher than that previously reported and was significantly greater in hemophiliacs than in non-hemophiliacs. HCV may be a contributing factor. 相似文献
93.
PE Newman 《Canadian Metallurgical Quarterly》1998,50(6):535-536
It is hypothesized that heretofore medically untreatable idiopathic tinnitus of intermittent intensity may be related to hyperuricemia. A number of pathogenic features common to both are given. Hyperuricemia is treatable. 相似文献
94.
95.
EH Uhlenhuth PE Alexander GM Dempsey W Jones BS Coleman AM Swiontek 《Canadian Metallurgical Quarterly》1998,47(1-3):183-190
Heart sounds produce an incessant noise during lung sounds recordings. This noise severely contaminates the breath sounds signal and interferes in the analysis of lung sounds. In this paper, the use of a wavelet transform domain filtering technique as an adaptive de-noising tool, implemented in lung sounds analysis, is presented. The multiresolution representations of the signal, produced by wavelet transform, are used for signal structure extraction. In addition, the use of hard thresholding in the wavelet transform domain results in a separation of the nonstationary part of the input signal (heart sounds) from the stationary one (lung sounds). Thus, the location of the heart sound noise (1st and 2nd heart sound peaks) is automatically detected, without requiring any noise reference signal. Experimental results have shown that the implementation of this wavelet-based filter in lung sound analysis results in an efficient reduction of the superimposed heart sound noise, producing an almost noise-free output signal. Due to its simplicity and its fast implementation the method can easily be used in clinical medicine. 相似文献
96.
We report here a photoneural regulation of nitric oxide synthase (NOS) activity in the rat pineal gland. In the absence of the adrenergic stimulation following constant light exposure (LL) or denervation, pineal NOS activity is markedly reduced. A maximal drop is measured after 8 days in LL. When rats are housed back in normal light:dark (LD) conditions (12:12), pineal NOS activity returns to normal after 4 days. A partial decrease in pineal NOS activity is also observed when rats are placed for 8 days in LD 18:6 or shorter dark phases, indicating that pineal NOS activity reflects the length of the dark phase. Because it is known that norepinephrine (NE) is released at night from the nerve endings in the pineal gland and this release is blocked by exposure to light, our data suggest that NOS is controlled by adrenergic mechanisms. Our observation may also explain the lack of cyclic GMP response to NE observed in animals housed in constant light. 相似文献
97.
Phase I trial of intravenous carboplatin and cyclosporin A in refractory gynecologic cancer patients
SK Chambers CA Davis JT Chambers PE Schwartz MI Lorber RE Hschumacher 《Canadian Metallurgical Quarterly》1996,2(10):1699-1704
Our objective was to determine the maximum tolerated dose of cyclosporin A (CsA) delivered as a loading dose (LD) and continuous i.v. infusion (CI) in combination with carboplatin in patients with refractory gynecologic cancers. Twenty-nine heavily pretreated patients (25 ovarian epithelial, 2 cervical, and 2 endometrial carcinomas) received 113 cycles of CsA and carboplatin from September 1989 to September 1991. Twenty-four of these 29 carcinomas were strictly defined to be platinum resistant. CsA was administered as a LD escalated from 6 to 10 mg/kg followed by a 24-h CI from 2.5 to 14.5 mg/kg/day. Carboplatin was targeted to an area under the time versus concentration curve (AUC) of 6 mg/ml x min and was not dose escalated. Whole-blood CsA concentrations (fluorescence polarization immunoassay) at the maximum tolerated dose (10 mg/kg LD, 14.5 mg/kg/day CI) ranged from 2.4 to 3.0 microgram/ml over 12 h. Estimated median carboplatin AUC, based on calculated carboplatin clearance, was 7.9 mg/ml x min. The dose-limiting toxicity of the combination of CsA and carboplatin was grade 4 thrombocytopenia. Grade 3 or 4 thrombocytopenia occurred in 35% of the patients, which could be explained by the effects of carboplatin (AUC of 6 mg/ml x min) alone. Overall, neutropenia occurred in 24% of the patients and anemia in 17% of the patients. Grade 3 or 4 nausea or vomiting was noted in 10 and 14% of the patients, respectively. Grade 3 hypertension during CsA administration occurred in 14% of the patients. No grade 3 or 4 nephrotoxicity was seen in this trial. Three objective responses were noted: one complete response (11 months) and one partial response (5 months), both in potentially platinum-sensitive patients with platinum-free intervals of only 9 months each. One platinum-resistant patient had a partial response for 21 months. Five additional patients experienced >75% reduction of CA-125 or a return to a normal CA-125 titer. We concluded that whole-blood CsA concentrations of >3.0 microgram/ml (as seen when CsA is used as a modulator of multidrug resistance) were not achievable in this combination with carboplatin in this population of heavily pretreated gynecologic cancer patients. However, because CsA is used in this trial as a chemosensitizer in platinum-sensitive tumors and as a chemomodulator of platinum resistance, we targeted a CsA concentration of >1.0 microgram/ml, which was achieved. The CsA dose recommended for a Phase II trial of this combination is 10 mg/kg LD and 11.6 mg/kg/day CI, which results in blood CsA concentrations ranging from 1.2 to 1.3 microgram/ml over 12 h. Responses in this population of refractory gynecologic cancer patients are unusual, and these encouraging results form the basis for a Phase II trial of this combination. 相似文献
98.
PE Rizzi RB Winter JE Lonstein F Denis JH Perra 《Canadian Metallurgical Quarterly》1997,22(21):2517-30; discussion 2531
STUDY DESIGN: Retrospective chart and complementary study review. OBJECTIVES: To describe the features of adult patients with spinal deformity and respiratory failure and to analyze the results of surgical treatment. SUMMARY OF BACKGROUND DATA: Many authors have studied the relation between spinal deformities and cardiorespiratory failure, but there exists little information about the benefits of reconstructive surgery in severely compromised patients. METHODS: The charts and complementary studies of 35 adult patients surgically treated between January 1, 1978, and December 31, 1994, were reviewed. The patients were 18 years old or older (average age, 36 years). They had spinal deformity of any etiology with respiratory insufficiency as evidenced by vital capacity of less than 60% of predictive normal, PaO2 less than 80 mm Hg, or PaCO2 more than 45 mm Hg. All had reconstructive spinal surgery in an attempt to improve their respiratory problem. RESULTS: Seven patients died within the first postoperative year, and one patient was lost to follow-up at 6 months. The other 27 patients had a mean follow-up time of 72 months. The 34 patients were divided into three groups: good, fair, and poor evolution. The patients in the good evolution group had a better preoperative general condition, had more correction of their deformities, had more improvement in their respiratory function, and had fewer complications than those in the other groups. The patients in the poor evolution group were older, had more cardiac problems, and had less correction at surgery. CONCLUSION: The results of surgery varied from extremely good to extremely bad. The seven patients who died within the first year had no benefit, but the 27 others did very well, usually gaining significant improvement of their respiratory function. Because the alternative to surgical correction is death, this study shows that, under the right circumstances, correction of spinal deformity and, therefore, correction of respiratory function can be life-saving. 相似文献
99.
AC Perkins M Frier AJ Hindle PE Blackshaw SE Bailey JM Hebden SM Middleton ML Wastie 《Canadian Metallurgical Quarterly》1997,70(834):603-611
The biodistribution and kinetics of an air filled human serum albumin microcapsule formulation (Quantison) intended for use as an intravenous ultrasound contrast agent have been examined. 12 healthy subjects were administered with approximately 50 million microcapsules per kilogram body weight, radiolabelled with 50 MBq 123I. Imaging was performed over a period of 58 h using a large field-of-view gamma camera and the amount of labelled material present in the blood, urine and faeces measured. Imaging demonstrated that the liver was the organ with the highest uptake, with a mean uptake of 41.8% (SD 10.4%) of the administered dose 1 h following administration. The maximum uptake of the agent in the lungs was low, mean 4.0% (SD 3.4%). A small amount of uptake was visible in the bone marrow; however, this was not quantifiable. There was also evidence of minimal myocardial activity within 5 min of administration. No adverse events were observed and there were no changes in any of the individual post-study indices. The present study demonstrates the safety of Quantison. Gamma scintigraphy played a useful role in confirming the biodistribution of the agent with little lung uptake, high liver uptake and evidence of myocardial uptake. 相似文献
100.
Glutamate, the neurotransmitter at most excitatory synapses in the brain, activates a variety of receptor subtypes that can broadly be divided into ionotropic (ligand-gated ion channels) and metabotropic (G-protein-coupled) receptors. Ionotropic receptors mediate fast excitatory synaptic transmission, and based on pharmacological and molecular biological studies are divided into NMDA and non-NMDA subtypes. The non-NMDA receptor group is further divided into AMPA and kainate subtypes. Virtually all fast excitatory postsynaptic currents studied so far in the central nervous system are mediated by the AMPA and NMDA subtypes of receptors. Surprisingly, despite extensive analysis of their structure, biophysical properties and anatomical distribution, a synaptic role for kainate receptors in the brain has not been found. Here we report that repetitive activation of the hippocampal mossy fibre pathway, which is associated with high-affinity kainate binding and many of the kainate receptor subtypes, generates a slow excitatory synaptic current with all of the properties expected of a kainate receptor. This activity-dependent synaptic current greatly augments the excitatory drive of CA3 pyramidal cells. 相似文献