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951.
Localized prepubertal periodontitis has been described as a host-defect mediated form of bacterially induced periodontitis, with an early onset and rapid progression around a few teeth in children prior to puberty. To further our understanding of the etiology of this disease, we have examined the microbiological components of subgingival dental plaque in 9 children with localized prepubertal periodontitis to determine if patterns of putative pathogens existed, and have compared these results with those obtained from 4 children with no periodontitis. Subgingival plaque samples were plated onto a selective medium for Actinobacillus actinomycetemcomitans and onto a non-selective medium for anaerobes, and the predominant cultivable microbiota of 2 sites per child was determined. The subgingival microbiota of children with localized prepubertal periodontitis clearly differs from non-diseased children in the detection of high levels of several suspected pathogens, including A. actinomycetemcomitans, Bacteroides intermedius, Eikenella corrodens, and Capnocytophaga sputigena. These putative pathogens were found in various combinations. These findings suggest that localized prepubertal periodontitis is associated with specific subgingival bacteria which are generally not found in children without periodontitis.  相似文献   
952.
本文报告707例精子自身抗体的研究结果。其中健康男性输精管绝育者278例,未绝育者231例;男性冠心病人输精管绝育者87例,未绝育者111例。明胶凝集试验(GAT)、试管玻片凝集试验(TSAT)和精子制动试验(SIT)检测结果表明:精子抗体在手术后6月内就已产生,并持续20年以上。曾作输精管绝育术的健康男性和冠心病人二组比较,抗体的阳性率和滴度皆无差异显著性。没有证据表明输精管绝育术后的精子免疫反应会增加冠心病的发病率。  相似文献   
953.
Summary Clinically relevant events possibly attributable to drug exposure have been monitored prospectively over a period of six months in 27 general intensive care units. Fifty-four events attributed to drugs were reported in 51 patients during their stay in hospital, corresponding to an overall incidence of 1.35%. The behaviour of the physicians following attribution of the events to a prescribed drug is analyzed and discussed in detail with respect to its relationship to the quality and severity of the reaction, and the classes of drugs. Twenty-four of the 4537 monitored admissions during the six months were due to life-threatening emergencies linked to the administration of drugs (14) and radio-contrast media (10) (overall incidence 0.5%). While the clinical burden attributable to adverse drug reactions in Intensive Care Units appears to be relatively small, the analysis shows that there is ample room for a greater reduction in their incidence. Coordinators: Drs M. L. Farina and G. Tognoni, Istituto di Ricerche Farmacologiche Mario Negri, Milan; Dr F. Procaccio, Neurosurgical ICU, Ospedale Ca' Granda, Niguarda, Milan.Investigators: Drs G. Barusco, Rovigo; F. Bassi, Milan; L. Bianchetti, Torino; E. Carchietti, Udine; G. Chilloni, Reggio Emilia; G. Costantini, Savigliano (CN); P. Ferrero, Aosta; E. Geat, Trento; F. Gorgerino, Torino; A. Lusini, Empoli (FI); G. Mantovani, Ferrara; S. Marchi, Bologna; P. Marcovigi, Forli; G. Marraro, Merate (CO); F. Merlo, Vicenza; E. Pagni, Bagno a Ripoli (FI); R. Pellegrino, Cuneo; C. Peruselli, Milan; A. Piovesano, Pordenone; R. Rinaldo, Cremona; R. Ruggerini, Piacenza; S. Sammartino, Torino; A. Sartore, Cittadella (PD); A. Scaglioli, Carpi (MO); G. Scopa, Terni; G. Zeffiro, Treviso; P. Zuccoli, Parma  相似文献   
954.
The behavioral effects following intrastriatal MPP+, the neurotoxic metabolite of MPTP, were evaluated in mice. Bilateral injections of 10 cro;g MPP+ to mice previously trained in the shuttle box paradigm produced a 66% decrease in striatal dopamine and significant deficits in all measures of conditioned avoidance responding. In addition, although these mice showed no deficits in baseline rotorod performance, challenge with the cholinergic agonist oxotremorine revealed that MPP+-treated mice exhibited an increased sensitivity to the disruptive effects of the drug at each dose and time point. Finally, MPP+-treated mice also exhibited an increase in tremor induced by 0.1 and 0.15 mg/kg oxotremorine. These observations are discussed in reference to idiopathic parkinsonism.  相似文献   
955.
Summary Combined Positron Emission Tomography (PET) and Proton Magnetic Resonance Imaging (MRI) study were performed in six patients with chronic supratentorial stroke to investigate whether remote hypometabolic regions revealed by PET showed any abnormality on MRI. Either regional oxygen consumption (n=4) or glucose utilization (n=2) were measured using PET and the 15O steady state 18FGD technique, respectively. Four patients, with deeply located brain lesions, showed a significant metabolic reduction in the overlying cerebral cortex. In the remaining two patients, affected by a large cortical infarct, there was a significant crossed cerebellar hypometabolism. The MRI weighted by the parameters spin density (), spin lattice (T1) and spin-spin (T2) relaxation times were obtained employing various sequences in the same subjects. In no patient did the MRI show any contrast modification in these hypometabolic remote regions, suggesting that subtle loss of tissue and/or biochemical change do not underlie the reduction in metabolic rate.  相似文献   
956.
Summary The unusual finding of an abnormal seasonal distribution of schizophrenic births, showing an excess of 10% in the winter or spring months and an equal deficit in the summer or autumn months, cannot be explained by artefacts. It has not yet been established whether the finding is specific to schizophrenia. We observed an excess of schizophrenic births of some 10% in March to May, significant at the 5% level, and a deficit of approximately the same size in June to August on the birth data of first-admission patients with the clinical diagnosis of schizophrenia. The data, obtained from the Mannheim Psychiatric Case Register, were compared with those of the Mannheim population and a control group matched by birth year and sex. The total population of mentally retarded children aged 7 to 16 years from the Mannheim population showed an excess of some 20% in April to June and an equal deficit in the last two quarters of the year, compared with the Mannheim population of the same birth years. The finding was not significant, but allowance must be made for the low case number of 415. We also compared 3409 first-admission patients with depressive syndromes (ICD 296 and 300.4) and 5615 first-admission patients with the diagnosis of neurosis and personality disorders (ICD 300–302, except 300.4, and 305–309) from the Mannheim Case Register with a control population and a parallel control group. Depressed males showed an excess of births in March to May, which was significant at the 1% level; the birth peak for females was smaller and not significant. The same findings were obtained for the category of neurosis and personality disorders, i.e. an excess of about 10% in March to May for males, significant at the 1% level, and a non-significant excess for females. Our findings are awaiting replication. Causal explanations will be discussed with great reservation. The procreational hypothesis, assuming those factors that lead to an equidirectional seasonal pattern of births with a slight deviation from the average of a year in the general population, to be reinforced in the disease categories mentioned, is regarded as the most simple and plausible explanation. It is based on the assumption that some of the parents of individuals suffering from schizophrenia, mental retardation or probably also some other mental disorders running from generation to generation, have a higher threshold in partner-seeking behaviour, which is overcome more easily in the summer months with the consequence of increased pregnancies.  相似文献   
957.
Summary Lectin-histochemical studies were performed on paraffin-embedded brain tissue sections to identify the specific sugar residues of undegraded stored substances in the cytoplasm of globoid cells from patients with globoid cell leukodystrophy. We studied brain tissues from six human patients with galactosylceramide lipidosis (i. e., Krabbe's disease) and compared them to brain tissues from animals with a similar enzyme deficiency including seven Twitcher mice, three dogs and two cats. The globoid cells in all 18 cases studied stained with succinylated-wheat germ agglutinin (S-WGA), but did not stain withDilichos biflorus agglutinin, soybean agglutinin orUlex europaeus agglutinin-I.Bandeirea simplicifolia agglutinin-I stained the globoid cells in Twitcher mice, dogs and cats but not those in humans.Concanavalia ensiformis agglutinin, wheat germ agglutinin andRicinus communis agglutinin-I all stained each of the globoid cells in the mouse, dog and cat tissues, but only in some of the human cases. Peanut agglutinin, however, variably stained globoid cells in the mouse and dog cases but not at all in the human and cat cases. These results demonstrate a common terminal carbohydrate residueN-acetyl glucosamine, which binds S-WGA in the undergraded material stored within the globoid cells in galactoceramide lipidosis. These cells also contained various other stored molecules with sugar residues whose nature is determined by species or individually.Supported by grants NS21765 and HD05515 from the National Institutes of Health  相似文献   
958.
Two females mother and daughter, were affected by a neuromuscular disorder, characterized by slow progression, humeroperoneal weakness and wasting, limited neck flexion, elbow and ankle joint contractures, cardiopathy and myopathic pattern on EMG. Muscle histology and histochemistry showed type I fiber atrophy and predominance in both. Cardiac abnormalities, in the first case, were suggestive of a hypertrophic cardiomyopathy while in the second hypotension and chronic bradycardia were present.Neurological signs, EMG and morphology seemed to point to a genetic variant of the form of dystrophy named Emergy-Dreifuss disease.The mode of transmission and cardiac abnormalities, however, raise the problem of variability even in this well-defined, usually X-linked, disorder.
Sommario Questa è la prima descrizione di madre e figlia affette da una infrequente malattia muscolare, caratterizzata da progressione lenta, ipostenia con atrofia a distribuzione omero-peroneale, presenza di contratture articolari, cardiopatia e pattern miopatico dell'EMG.Istologia e istochimica muscolare hanno mostrato in entrambi i soggetti atrofia e predominanza delle fibre del I tipo. Le anormalità cardiologiche rilevate nel 1° caso, erano a favore di una cardiomiopatia ipertrofica, mentre nel secondo caso erano presenti ipotensione e bradicardia.Segni neurologici, elettromiografici, reperti istologici ed istochimici sembrano configurare nelle nostre pazienti una variante genetica della forma di distrofia muscolare chiamata Emery-Dreifuss disease. Tuttavia, la modalità di trasmissione e il tipo delle anormalità cardiologiche, diverse nelle due pazienti, sollevano il problema di variabilità fenotipiche, anche in entità clinico-genetiche usualmente ben definite quali la malattia di Emery-Dreifuss.
  相似文献   
959.
A multicenter prospective investigation was conducted in 17 teaching and general hospital in Italy to assess the efficacy of the care delivered to previously untreated patients with epilepsy. 175 cases were included and allocated to monotherapy. Only 112 cases completed the first year of follow-up. Of these, 59 (52.7%) were completely controlled and 53 (47.3%) had one or more seizure relapses. Controlied and uncontrolled patients were compared with respect to the main variables believed to influence non-responsiveness to standard therapy. The proportion of cases with relapses was significantly associated with the number of seizures reported before treatment was started. Selected seizure patterns (absences, myoclonic seizures) and prolonged disease duration were also reported more frequently among patients with recurrences. The implications of these findings are discussed with respect to drug response and prognosis of epilepsy.
Sommario Il presente studio consiste in una indagine prospettica multicentrica condotta in 17 centri ospedalieri italiani sulla efficacia del trattamento e sulla prognosi della malattia in pazienti con epilessia alla prima diagnosi. Dei 175 casi ammessi allo studio, 112 hanno completato il primo anno di osservazione. Di questi, 59 (52,7%) risultavano completamente controllati e 53 (47,3%) avevano presentato una o più crisi durante il follow-up. Le principali variabili ritenute responsabili di una insoddisfacente risposta al trattamento vennero quindi esaminate nei due gruppi. Il rischio di recidiva di crisi risultava significativamente correlato al numero di crisi presentate prima del trattamento. Inoltre, i pazienti con crisi nel follow-up presentavano una maggior durata di malattia o specifici tipi di crisi (assenze, crisi miocloniche). Il significato di tali dati è discusso in riferimento alle modalità di trattamento e agli altri fattori implicati nella prognosi dell'epilessia.
  相似文献   
960.
Radiographic quantification of alveolar bone level changes   总被引:3,自引:0,他引:3  
The "random burst" theory has recently been proposed as an explanation of the pattern of periodontal disease progression. The theory predicts that the progression of bone loss at individual sites is not dependent upon previous bone loss and age. A longitudinal radiographic study was designed to test this hypothesis, and to describe the changes in bone level over 2 years in a group of 180 subjects (18-68 years of age) who were not under systematic periodontal treatment. The results indicated that 94% of the sites did not show significant changes in the alveolar bone level during the observation period. The mean annual bone loss for the total population was 0.11 mm. By regressing longitudinal bone loss upon age, it was shown that the rate of bone loss increased rapidly between 33 and 56 years of age while a different pattern was shown for the age intervals 18-32 and 57-68 years. Also, the rate of bone loss increased with increasing initial bone loss. This was less evident in the oldest age group. It was concluded that the progression of bone loss in the present material is consistent with a "burst" theory. However, the progression did not occur randomly with regard to previous loss of alveolar bone and time.  相似文献   
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