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991.
Summary Galactocerebrosidase-deficient oligodendrocytes of twitcher (twi/twi) mice degenerate prematurely. Transplantation of normal bone marrow cells has been shown to alleviate symptoms and to prolong survival time. However, characteristic ataxia (twitching) is not cured. In an attempt to improve further the condition of twitcher mice, allogeneic foetal liver cells were transplanted as a source of normal haemopoietic stem cells and supplemented with intracerebral transplantation of foetal brain cells. A reliable method was developed to detect donor-type cells in brain tissue. Bacteriophage . transgenic foetal mice were used as donors of both foetal liver and brain cells. Integrated copies of . DNA in donor cells were detected byin situ hybridization with biotinylated probes, which were then stained using streptavidin alkaline phosphatase. This technique was combined with immunohistochemistry to distinguish donor-type oligodendrocytes from macrophages. Immunoperoxidase staining with an antiserum to carbonic anhydrase-II produced dark perikarya of oligodendrocytes. The results demonstrated that local foetal brain cell grafts resulted in a wide dissemination of donor-type oligodendrocytes throughout the twitcher brain. The addition of a foetal brain cell graft to haemopoietic cell transplantation resulted in significantly prolonged survival of twitcher mice.  相似文献   
992.
Obesity is characterized by a high risk for glucose intolerance and cardiovascular disease. Since magnesium deficiency or depletion have often been associated with both pathologies, is of interest to study magnesium status in severely obese subjects before any form of treatment. Negative magnesium balances have been described in overweight persons submitted to total starvation, hypocaloric diets, and obesity surgery. For this reason 80 non-diabetic obese men and 118 age-matched obese women were studied. Serum and erythrocyte magnesium concentrations were significantly higher in the male population but the mean values were not suggestive of a magnesium deficit before any form of treatment was started. Since metabolic abnormalities and cardiovascular risk are greater in patients with upper body fat distribution (UBFD) both sexes were subdivided according to "waist-to-hip" circumference ratio. No difference could be shown in the obese men but in women, UBFD subjects showed higher basal insulin levels and increased erythrocyte magnesium concentration as compared to those with classical gynoid fat distribution. A 75 g oral glucose tolerance test enabled the subjects to be subdivided into those with normal or impaired glucose tolerance (IGT). The IGT group in both sexes was older and more obese. Mean values of serum magnesium and erythrocyte magnesium were not decreased despite the more pronounced insulin resistance in the IGT group. However a significant negative correlation was found between fasting blood sugar/insulinaemia and erythrocyte magnesium, showing that this middle-aged obese population can maintain normal circulating levels of magnesium, in contrast to type II diabetics or older subjects where for other reasons (urinary losses or decreased intake) magnesium status is interfered with.  相似文献   
993.
A R De Jong  M Rose 《Pediatrics》1991,88(3):506-511
Child sexual abuse criminal court cases from a 12-month period were reviewed to determine the frequency and significance of physical evidence in legally "proven" felony cases with penetration. One hundred fifteen consecutive cases were reviewed, and 87 (76%) had resulted in conviction of the perpetrator on felony charges. Charges of vaginal rape were made in 88 cases, and oral and/or anal sodomy in 67 cases. Physical evidence was present in only 23% of all cases that resulted in felony convictions. Felony convictions were obtained in 67 (79%) of 85 cases without physical evidence and in only 20 (67%) of 30 cases with physical evidence. Eight of the 10 cases without physical evidence that did not result in conviction involved victims younger than 7 years of age. Cases involving the youngest victims had a significantly lower conviction rate (12 of 23), despite a very high frequency (13 of 23) of physical evidence (P less than .0005). Physical evidence was neither predictive nor essential for conviction. Successful prosecution, particularly in cases involving the youngest victims, depended on the quality of the verbal evidence and the effectiveness of the child victim's testimony.  相似文献   
994.
We evaluated polymorphonuclear leucocyte (PMN) chemotaxis and cortisol levels in cord blood from 15 healthy term infants delivered by caesarean section and from 15 healthy vaginally delivered term infants. Mean neutrophil chemotaxis was significantly higher in infants delivered by caesarean section (78.3±23.4m) than in vaginally delivered infants (57.8±16.6 m;P=0.01). Mean blood cortisol level was significantly lower in infants delivered by caesarean section (9.14±2.76 g/dl) than in infants born by vaginal delivery (20.71±6.98 g/dl;P=0.0001). No relationship was found between PMN chemotaxis and blood cortisol level. The higher neutrophil chemotactic activity observed in infants delivered by caesarean section could be related to general maternal anaesthesia.  相似文献   
995.
SGA infants have an increased incidence of low Apgar scores. At the same time they frequently have a high hematocrit. Since both affect outcome, it is important to know if a relationship exists between these two factors. In a study of 139 SGA newborns many had low Apgar scores at one minute: 63% of the preterms and 29% of the fullterms. Frequent abnormal hematological findings included high hematocrit. We found a positive correlation between hematocrit and the Apgar score at one minute of life that was statistically significant. The babies with a high hematocrit had significantly more often good Apgar scores. The correlation was present in preterm babies (r = 0.55) as well as in fullterms (r = 0.32). It is concluded that a high hematocrit probably protects the SGA newborn against acute perinatal asphyxia. It is possible that both low Apgar scores and "normal" hematocrit are signs of a chronically impaired SGA fetus.  相似文献   
996.
Summary We report very large hepatic peroxisomes (d-circle >1 m) in a patient with rhizomelic chondrodysplasia punctata and a patient with acyl-CoA oxidase deficiency. The effects of peroxisomal enlargement on the enzymatic activity are discussed. As increase in peroxisomal size is also reported in at least 12 other patients with peroxisomal disorders, we propose, a relationship between the enlargement of the organelles and their functional deficiency.  相似文献   
997.
Aim of this work is to show the results of the evaluation of the sensitometric properties of a new Du Pont anti cross-over radiographic film system called Ultra Vision, based on a new film and different YTaO4 undoped screens whose emission is centered at about 335 nm. Fog, contrast, latitude, sensitivity, noise and resolution were tested: the MTFs were obtained by exposing a standard resolution pattern and using the "zero"-frequency step as a knife edge. The image of this knife edge was scanned with a microdensitometer with a 20 microns slit. The results (at 70 kVp with 2.5 mm Al and 2.5 mm Cu total filtration), compared with those of Du Pont conventional radiographic screen-film systems Cronex 10 S/Quanta, show that the new system significantly increases contrast, sensitivity and resolution and will consequently improve, in the clinical use, radiographic image quality.  相似文献   
998.
Calbindin-D28K (CaBP28k)-like Immunoreactivity in Ascending Projections   总被引:2,自引:0,他引:2  
This study concerns the involvement of calbindin-D28K (CaBP28k)-containing neurons in ascending spinal projections to the brainstem (nucleus of the solitary tract, lateral reticular nucleus area), pontine (parabrachial area) and mesencephalic (periaqueductal grey) structures. All these central structures are important in the processing of visceroception and visceronociception and all are targets for spinal efferents from similar areas. CaBP28k controls the excitability of cells by acting on intrinsic calcium metabolism. Results refer to the caudal spinal areas where the visceroceptive regions are concentrated. Experiments were performed through a double labelling approach that combined the retrograde transport of a protein - gold complex to identify the projection cells and immunohistochemistry to identify the CaBP28k-positive cells. The caudal spinal cord is rich in both CaBP28k-containing and projection cells. Cells colocalizing the protein and the retrograde tracer were quite numerous, with a particularly high concentration in the superficial layers of the dorsal horn (laminae I and outer II) and the lateral spinal nucleus. The other spinal areas containing immunoreactive projection cells were the reticular part of the neck of the dorsal horn, the medial laminae VII and VIII, lamina X and the sacral parasympathetic nucleus. The superficial layers and the neck of the dorsal horn are targets for nociceptive, visceroceptive and thermal inputs; the sacral parasympathetic column and lamina X are involved in visceroceptive integration. A functional role for the lateral spinal nucleus has not yet been established. Quite similar results were obtained for each of the ascending pathways under study. The high incidence of CaBP28k in spinal pathways suggests that calbindin has a major role in controlling the excitability of spinal cells subserving the processing of visceroception and/or visceronociception information to supraspinal levels. The participation of CaBP28k-immunoreactive cells in spinal ascending tract cells largely outnumbers those previously reported for various neuropeptides (Leah et al., Neuroscience, 24, 195 - 207, 1988)  相似文献   
999.
We report the case of a 22 year old woman with congenital generalized lipodystrophy who presented a left brachiocrural pyramidal hemisyndrome, bilateral cerebellar signs and a left cranial nerve VI deficit. The clinical pattern had a tendency to regress. MRI brainscan, CSF examination and clinical features led to the diagnosis of probable demyelinating syndrome. Published data on CNS involvement in patients with congenital generalized lipodystrophy are few and we have found no cases in which a demyelinating syndrome is associated. In the case we report it is tempting to see the disorder of the lipid metabolism underlying the congenital generalized lipodystrophy as underlying the myelin disorder as well.
Sommario Descriviamo il caso di una paziente di 22 anni, affetta da Lipodistrofia Congenita Generalizzata, che ha presentato una sintomatologia caratterizzata da emisindrome piramidale brachiocrurale sinistra, segni cerebellari bilaterali e deficit del VI nervo cranico di sinistra. Il quadro clinico ha avuto una tendenza alla regressione. La RMN encefalo, l'esame del liquor e la clinica hanno fatto porre diagnosi di probabile sindrome demielinizzante. I dati della letteratura relativi al coinvolgimento del SNC in pazienti con Lipodistrofia Congenita Generalizzata sono scarsi ed in particolare non abbiamo rilevato casi di associazione con sindrome demielinizzante. Nel caso descritto è suggestivo che la turba del metabolismo lipidico alla base della Lipodistrofia Congenita Generalizzata possa essere in rapporto all'interessamento della mielina.
  相似文献   
1000.
Summary In three general medical settings (general practice, hospital medical wards and emergency rooms) about 20% of the adult attenders had a DSM-III mental disorder, mainly in the area of affective and anxious disorders. Some of these disorders were quite severe. Of those cases reassessed 1 year and 2 years after the first interview, less than a quarter reached a no-diagnosis status. The chronicity of most cases dependent on the interplay not only of either relapse or duration of the main disorder but also of comorbidity and incidence of new disorders. A high incidence of more transient disorders in subjects who were well at first assessment was also found.  相似文献   
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