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51.
The emergence of a near-haploid clone of cells in blast phase chronic myelogenous leukemia is an unusual event. We report such a case and review eight other cases described in the English literature. The significance of the substantial loss of genetic material is discussed as is the phenotypic and genotypic heterogeneity observed in this group of patients.  相似文献   
52.
The goal of the present study is to develop a technique for laparoscopic aortobifemoral bypass.Piglets weighing between 60 and 78 kg were anesthetized with halothane. The lateral retroperitoneal approach was preferred to the more familiar anterior transperitoneal approach and was successfully completed in 19 piglets. The piglets were placed in the right lateral decubitus position. The first port (2 cm) was inserted halfway between the tip of the 12th rib and the iliac crest. Four other trocars were placed in the retroperitoneum after balloon inflation had allowed creation of a space which permitted visualization of the aorta from the left renal artery down to the aorto-iliac junction. After evacuation of the retropneumoperitoneum, the cavity was maintained using an abdominal lift device and a retractor.Using this approach, we performed four aortobifemoral bypasses (end-to-end aortic anastomosis) after conventional intravenous heparinization (100 IU/kg) in less than 4 h. Blood loss did not exceed 250 ml and the hematocrit remained stable. Postmortem evaluation of the grafts revealed they were positioned as in a conventional bypass, their limbs having followed in the created retroperitoneal tunnels along the path of the native arteries. No mortality occurred before sacrifice of the animals. We believe that this first performed series of totally retroperitoneal laparoscopic aortobifemoral bypasses in the porcine model is useful in preparation for human application due to the anatomical similarities in the periaortic region.  相似文献   
53.
There are conflicting reports on the relationship between cerebellar vermal lobule hypoplasia and autism. Using quantitative magnetic resonance image analysis, we measured the cerebellar vermis in 125 normal individuals with a broad age range and 102 patients with a variety of neurogenetic abnormalities. We conclude that hypoplasia of cerebellar vermal lobules VI and VII is a nonspecific finding that even occurs in several conditions without autistic behavior. This suggests that it is not a specific neuroanatomical marker for autism, nor is cerebellar dys- genesis likely to be solely responsible for clinical autistic behaviors.  相似文献   
54.
The aim of this study was to evaluate the cerebral synthesis of eicosanoids in the asphyctic newborn and to investigate the relation between the prostanoid profiles in cerebrospinal fluid (CSF) and the appearance and severity of hypoxic-ischaemic encephalopathy (HIE). Levels of 6-keto-PGF 1-α, TXB2, PGE2 and PGF2-α in CSF were measured in 40 full term newborns during the first day of life. Thirty of these newborns had birth asphyxia and were divided into three groups: 10 without HIE, 12 with mild HIE and 8 with moderate-severe HIE. They were compared to a control group of 10 non-hypoxic newborns. Determinations of the metabolites in CSF were performed by RIA and expressed as pg/ml (mean ± SD). The CSF TXB2 (thromboxane A2 metabolite) in asphyxiated newborns was always higher than in the control group (28.12 ± 10.6), and related to the severity of HIE ( p = 0:005): without HIE (50.84 ± 16.4; p = 0:02), mild HIE (80.65 ± 12.64; p ± 0:01) and moderate-severe HIE (178.14 ± 20.5; p < 0:01). The CSF 6-keto-PGF 1-α (prostacyclin metabolite) in asphyxiated newborns was always higher than in the control group (80.55 ± 12.56), but indirectly related to the severity of HIE: without HIE (240.95 ± 28.12; p < 0:01), mild HIE (183.65 ± 30.1; p < 0:01) and moderate-severe HIE (140.55 ± 25.12; p < 0:01). In the moderate-severe HIE group, the increase in TXB2 was higher than the rise in 6-keto-PGF 1-α.  相似文献   
55.
OBJECTIVE: To develop a distance measure based methodology to support the morphological evaluation of high grade prostatic intraepithelial neoplasia (PIN), a direct precursor of prostate cancer. METHODS: Eight morphological and cellular features were analysed in 20 cases of high grade PIN found in radical prostatectomy specimens from patients with adenocarcinoma. The diagnostic distance was evaluated to measure the extent to which the feature outcomes of the individual high grade PIN cases differed from the expected outcome profile of normal prostate, low and high grade PIN, and cribriform and large acinar adenocarcinoma. The belief value for high grade PIN was evaluated with a Bayesian belief network (BBN). RESULTS: Complete separation existed between the cumulative absolute diagnostic distances of these 20 cases from the prototype feature outcomes of high grade PIN and normal prostate the values for which were < or = 3 (range 0 to 3) and > or = 9 (range 9 to 15), respectively. The distances from low grade PIN (range 3 to 9), cribriform adenocarcinoma (range 2 to 8), and large acinar adenocarcinoma (range 5 to 10) were intermediate and showed overlap in their distribution. When taking into consideration whether the severity of feature changes was increasing or decreasing in comparison with the category prototype outcomes, the cumulative directional diagnostic distances from high grade PIN ranged from -3 to +3. Positive distance values were seen relative to low grade PIN (range +3 to +9) and relative to normal prostate (range +9 to +15). Negative values were found relative to cribriform adenocarcinoma (range -8 to +2). The distance values from large acinar adenocarcinoma ranged from -2 to +4 and partly overlapped with those from the high grade PIN category. A bivariate scattergram derived from both diagnostic distance measures showed excellent separation between the groups' distances. BBN analysis confirmed the morphology based diagnosis. The distance evaluation resulted in 18 cases whose belief value for high grade PIN ranged from 0.60 to 0.87. In the remaining two cases the results of the BBN analysis showed a belief value of 0.50 and 0.57 for low grade PIN and of 0.49 and 0.38 for high grade PIN, respectively. CONCLUSIONS: Distance measure based methodology represents a useful diagnostic decision support tool for the accurate evaluation of high grade PIN.  相似文献   
56.
57.
This report explores the possibility of redefining risk factors so as to improve their observed associations with prevalent coronary heart disease (CHD). A large cross-sectional community study of 5,895 white males and females aged 25-64 years yielded 240 cases of confirmed angina pectoris and 361 of confirmed myocardial infarction. Odds ratios for CHD end-points by level of risk factors when risk factors were expressed in the conventional manner (e.g. total cholesterol, systolic and diastolic blood pressure or current smoking) were often low and not statistically significant. Redefinition of risk factor variables in a manner that improved their specificity or compensated to some extent for the decreased risk factor exposure as a result of a CHD event (e.g. stopping smoking after a myocardial infarct) improved the strength of association. In this study, the most useful cholesterol variable was total cholesterol minus high-density lipoprotein cholesterol; for blood pressure the most useful variable was a blood pressure of 160/95 mmHg or above and/or being on anti-hypertensive treatment; and for smoking the most useful variable was the total duration of smoking (previous and current). Strong associations with CHD end-points were also found for conventionally expressed serum uric acid, diabetes prevalence (females) and family history of CHD. The study suggests that appropriate redefinition of risk factor variables and CHD end-points in cross-sectional studies yields associations similar in strength and direction to those found in prospective studies.  相似文献   
58.
Recurrent hip dislocation in intermediate spinal atrophy   总被引:1,自引:0,他引:1  
Recurrent hip dislocation after corrective orthopaedic surgery in children and teenagers with intermediate spinal atrophy has not been reported in the literature. Four cases with long-term follow-up are presented. These represent the only cases surgically treated in 30 years of following spinal atrophy patients. Thus, it seems significant that all hips redislocated after the surgical procedure. In addition, two patients had second operations with subsequent dislocation. Pelvic obliquity should not be the basis for the surgery, as spinal fusion is generally necessary for wheelchair users. The sagacity of performing surgery for hip dislocations is raised.  相似文献   
59.
Summary: Purpose: Quantitative MRI techniques provide an unparalleled opportunity to examine in vivo the relationship between the extent and laterality of hippocampal pathology and associated neuropsychological deficits. The purpose of this study was to examine the nature of the relationship between quantitative measures of hippocampal pathology and neuropsychological measures, using a multivariate approach. Methods: We examined the relationship between two MRI measures of hippocampal structure; hippocampal volumes (HCvol) and T2 relaxation times (HCT2), and memory performance, in 80 presurgical temporal lobe epilepsy patients. Results: As a group, patients with left hippocampal sclerosis (LHS) performed more poorly that those with right hippocampal sclerosis (RHS) on immediate and delayed prose recall. In the group as a whole, right hippocampal volume was significantly correlated with the delayed recall of a complex figure. None of the verbal memory test scores were significantly correlated with the right or left HCvol or HCT2 measures. However, stepwise multiple regression analyses indicated that up to a third of the variation in specific test scores could be explained by the quantitative MRI hippocampal measures in conjunction with chronological age, and age at onset of habitual epilepsy. Left hippocampal measures explained 24% of the variance in the story-recall tasks, while right hippocampal measures explained 18% of the variance in a design-learning task and 32% of the variance in a figure-recall task. Conclusions: Our results provide some support for the lateralised model of material specific memory deficits, but suggest that a number of demographic and epilepsy-related factors may interact with the extent and laterality of hippocampal pathology in shaping the nature of the associated neuropsychological deficit.  相似文献   
60.
A series of 73 dibenzo[a,d]cycloalkenimines were synthesized and evaluated for their ability to displace (+)-10,11-dihydro-5-methyl-5H-dibenzo[a,d]cyclohepten-5,10-imine ([3H]-(+)-10) from its specific binding site on rat cortical membranes. A number of the more active compounds (Ki ranging from 0.006 to 0.21 microM) were evaluated for N-methyl-D-aspartate (NMDA) antagonist activity in the rat cortical slice (Kb ranging from 0.08 to 0.9 microM) and anticonvulsant activity in the mouse against NMDA induced convulsions. The ED50 values ranged from 0.22 to 7.76 mg/kg and correlated reasonably well with the Kb determination. In the dibenzo[a,d]cyclohepten-5,10-imine series, the (+)-5S,10R enantiomer displayed consistently higher levels of biological activity. While substitution at the 3-position of (+)-10 with electronegative atoms generally increased in vitro activity, a loss of potency relative to (+)-10 (MK-801) was observed in vivo for all of the compounds tested.  相似文献   
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