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41.
Two patients with Ph-positive chronic myelocytic leukemia in erythroblastic transformation and rearrangement of the short arm of chromosome 18 are reported. Fluorescence in situ hybridization studies showed that the 18p rearrangement resulted from translocation of the main part of chromosome 22 long arm to 18p, including BCR-ABL1 fusion. The 18p abnormality resulted, thus, in loss of 18p and duplication of BCR-ABL1 in both patients. The possible relation to the erythroblastic type of blastic phase is briefly discussed. In addition an apparently intact germline ABL1 gene was duplicated and inserted into chromosome 6 at band p21 in one of these patients.  相似文献   
42.
This study was undertaken to compare the effect of glucose injection on the pharmacokinetic behavior of a soluble dye in normal and tumoral tissues. The measurements were done using a noninvasive fluorescent spectroscopy in situ and in real time. The experiments were performed on three groups of animals with calcein as a soluble pH-insensitive fluorescent dye combined or not with glucose. Glucose solution was injected 5 or 30 min before calcein. Fluorescence emission intensity was recorded on normal and tumor tissues with an optical multichannel analyzer. Calcein concentration was also measured in blood using repetitive blood sampling. In the control group (without glucose injection), calcein is rapidly cleared from the blood, with a slow tissue clearance. Fluorescence of normal tissue was higher than fluorescence measured in tumor tissue. When glucose is injected 5 min before calcein, there was a rapid increase of tissue fluorescence followed by a plateau remaining during the whole experiment. No difference between tumor and normal tissue fluorescence intensity was observed. When glucose was injected 30 min before calcein, the plateau phase was reduced to 50 min in normal tissue. Tumor tissue fluorescence displays no distinct plateau phase. These results clearly showed the effect of glucose injection in situ and in real time, by a noninvasive method, on the pharmacokinetic of a soluble dye in a tumor tissue compared to a normal tissue. Differences between blood compartment and tissues kinetic profiles were also clearly demonstrated.  相似文献   
43.
BACKGROUND: The assessment of perinatal depressions and coping style. Methods: With depression scales (EPDS, GHQ.12) and Carver's BriefCope, the authors compared the prevalence rates of pre and postnatal depression in a cohort of 277 French women. RESULTS: Their work revealed very high levels of prenatal depression (almost 20%) and less important but nonetheless sizeable rates (11%) of postnatal depression, making such perinatal depressions a major public health concern. The coping styles proposed in Carver's public health BriefCope questionnaire make it possible to significantly differentiate during these two periods between depressive women and their non-depressed counterparts. CONCLUSIONS: This enables us to underline factors of risk and protection suggesting the importance of setting up compensatory and preventive systems and evaluating their pertinence in the framework of future research.  相似文献   
44.
BACKGROUND: Endometriosis and possible rectal involvement are difficult to assess by physical examination. Previous studies have shown the diagnostic value of magnetic resonance imaging and rectal endoscopic sonography (RES) in this setting, but not that of transvaginal sonography (TVS). The aims of this study were to compare the accuracy of TVS and RES for the diagnosis of pelvic endometriosis, and to compare the results with histological findings. PATIENTS AND METHODS: In a prospective study, 30 consecutive patients referred with clinical signs of endometriosis underwent TVS and RES; the images were interpreted blindly with regard to physical findings. RESULTS: Endometriosis was confirmed histologically in 28 (93%) of the 30 patients. Endometriomas were also present in 67% of cases. For the diagnosis of uterosacral endometriosis, the sensitivity, specificity, and positive and negative predictive values of TVS and RES were 75 and 75%, 83 and 67, 95 and 90%, and 45 and 40% respectively. For the diagnosis of rectosigmoid endometriosis, the sensitivity, specificity, and positive and negative predictive values of TVS and RES were 95 and 82%, 100 and 88%, 100 and 95%, and 89 and 64% respectively. CONCLUSION: Despite the large proportion of our patients who had intestinal endometriosis, representing a possible source of bias, our results suggest that TVS is as efficient as RES for detecting posterior pelvic endometriosis and should therefore be used as the first-line examination.  相似文献   
45.
Nitric oxide is involved in the neutrophil and macrophage killing of the protozoan parasite Entamoeba histolytica. In the present study, we found that cysteine proteinases, significant contributors to amebic virulence and alcohol dehydrogenase 2, an enzyme absolutely required for the survival of the parasite, are both significantly inhibited by S-nitroso-glutathione, a physiological nitric oxide donor, within the concentration range 0.5-2.0 m M.  相似文献   
46.
Spinal muscular atrophy (SMA) is, after Duchenne muscular dystrophy,the most common neuromuscular disorder in childhood. The generesponsible for childhood SMA has been mapped to the q11. 2– q13. 3 region of chromosome 5. We have extended ourlinkage studies of SMA In the French - Canadian population toInclude microsatellite markers at the D5S125, D5S351, D5S435,JK53CA1/ 2 and MAPI B locl. These markers span about 4 cM ofthe SMA candidate region. We observed significant evidence forlinkage between SMA and all the markers tested. The analysisof recombinant chromosomes provide evidence for the followinggenetic order: D5S125-D5S435-MAP1B-3'-JK53CA1/2 and places D5S351proximal to JK53CA1/2. Furthermore, we confirm the current localizationof the SMA gene distal to D5S435. Finally, we provide demonstrationof significant linkage disequilibrium between childhood-onsetSMA and four of the five marker loci, D5S125, D5S435, D5S351and JK53CA1/2. Analysis of SMA-region haplotypes suggests thatthere may be a predominant SMA allele that is present on about17% of SMA chromosomes in this sample of the French - Canadianpopulation. We conclude that the observed linkage disequilibriumis likely due to genetic drift among regions of Quebec, consistentwith this population's early history.  相似文献   
47.
We investigated the effects of short duration running training on resting and exercise lung function in healthy prepubescent children. One trained group (TrG) (n = 9; three girls and six boys; age = 9.7 ± 0.9 year) participated in 8 weeks of high-intensity intermittent running training and was compared to a control group (ContG) (n = 9; four girls and five boys; age = 10.3 ± 0.7 year). Before and after the 8-week period, the children performed pulmonary function tests and an incremental exercise test on a cycle ergometer. After the 8-week period, no change was found in pulmonary function in ContG. Conversely, an increase in forced vital capacity (FVC) (+7 ± 4% ; P = 0.026), forced expiratory volume in one second (+11 ± 6% ; P = 0.025), peak expiratory flows (+17 ± 4% ; P = 0.005), maximal expiratory flows at 50% (+16 ± 10% ; P = 0.019) and 75% (+15 ± 8% ; P = 0.006) of FVC were reported in TrG. At peak exercise, TrG displayed higher values of peak oxygen consumption (+15 ± 4% ; P<0.001), minute ventilation (+16 ± 5% ; P = 0.033) and tidal volume (+15 ± 5% ; P = 0.019) after training. At sub-maximal exercise, ventilatory response to exercise was lower (P = 0.017) in TrG after training, associated with reduced end-tidal partial oxygen pressure (P<0.05) and higher end-tidal partial carbon dioxide pressure (P = 0.026). Lower deadspace volume relative to tidal volume was found at each stage of exercise in TrG after training (P<0.05). Eight weeks of high-intensity intermittent running training enhanced resting pulmonary function and led to deeper exercise ventilation reflecting a better effectiveness in prepubescent children.  相似文献   
48.
A recent molecular phylogenetic study has suggested that the genus Hirudo contains a neglected species previously known as the orientalis coloration type of the medicinal leech Hirudo medicinalis. In this paper, the new species is formally described as Hirudo orientalis sp. n. It can most readily be identified by the grass green coloration of the dorsum, segmentally arranged pairs of black quadrangular or rounded dots on its paramarginal dorsal stripes and similarly arranged, but less regular light-colored markings on the predominantly black venter. It has medium-sized epididymes and an evenly coiled vagina. H. orientalis is known from Transcaucasia, Iran, and Uzbekistan. It is widely used in medicine as the “medicinal leech.” Very little is known about its exact distribution, specific habitat, and conservation status. The paper contains an identification key to all species of the genus Hirudo.  相似文献   
49.
Evidence supports the role of exercise training and probiotics on reducing obesity. Considering the relationship between obesity and high-fat diet with anxiety indices, the aim of this study was to assess the effect of probiotic supplementation and high-intensity interval training (HIIT) on anxiety-like behaviors, corticosterone and obesity indices in high-fat diet (HFD)-induced obesity mice. Thirty male adult C57BL/6 mice were randomly divided into five groups: (1) Control with normal diet (CON), (2) High-fat diet (HFD), (3) HFD + exercise training (HT), (4) HFD + probiotics supplement (HP) and (5) HFD + exercise training +probiotics (HTP). Exercise training consisted of 8 weeks of high-intensity interval training (HIIT) programs. Probiotics supplement included 0.2 mL Lactobacillus rhamnosus GG. Anxiety-like behaviors were measured by open field (OF) and Elevated plus maze (EPM). OF and EPM tests, visceral fat mass (VFM) measurement, and blood sampling for corticosterone were performed after the intervention. Bodyweight was measured at different stages during the intervention. HFD regime in C57BL/6 mice increased bodyweight, VFM, and serum corticosterone levels and anxiety-like behaviors (p < 0.05). HIIT, probiotic and their combination, decreased bodyweight, VFM, and serum corticosterone levels and improved anxiety-like behavior in the HFD mice (p < 0.05). The effect of a combination of HIIT and probiotic on most of the anxiety indices was more than each one separately (p < 0.5). HIIT and probiotic supplements separately or above all in combination, may have beneficial effects in reducing obesity and anxiety indices.  相似文献   
50.
Serge  R  Bitemo  高勇 《医学教育探索》2001,(4):338-340
针对传统RESS过程中存在着颗粒质量和产量问题,本文分别以超临界CO2作为溶剂在萘的固态和熔融状态下利用RESS过程制备了萘的超细颗粒,研究了萘在固态和熔融态下各种操作变量,如萃取温度和压力、膨胀前温度和喷嘴尺寸等对产品尺寸的影响。结果表明,膨胀前温度和萃取压力的作用规律相同,提高膨胀前温度则颗粒变大,提高萃取温度,颗粒尺寸变小;而在熔融状态下反之,在该研究范围内,喷嘴尺寸的熔融态和固态下对颗粒尺寸影响不大。  相似文献   
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