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1.
A simple method to cultivate pollen tubes in a gelatin medium is presented. After the growth of the pollen tubes in the culture medium, they are fixed, dehydrated, and embedded in resin for ultramicrotomy. The method is easy and does not require the purchase of special materials beyond those needed for the usual techniques for studying biological specimens under transmission electron microscopy.  相似文献   

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INTRODUCTION: Multiple sclerosis (MS) is a demyelinating disorder of the CNS, of autoimmune pathology and unknown aetiology. Several theories regarding its aetiology have been suggested, although none seems to be completely convincing. Genetically predisposed persons are affected, therefore groups of MS are seen in certain families. OBJECTIVES: To describe the family links, type of illness and evolution of 12 patients from six families with two or more members diagnosed as having MS, and to evaluate any differences from the other cases recorded in our data base. PATIENTS AND METHODS: We studied 12 patients diagnosed on the criteria of Poser, and with at least one first or second degree relation with MS. We compared clinical data, form of presentation and course with 127 patients recorded in the data base. RESULTS: We describe six families: two homozygotic twins, two families in which transmission was from father to child and three families with first degree cousins affected. We found no clinical variation in the presentation, number of attacks or evolution, as compared with the other patients. Nor was there homogeneity between the familial forms of MS. CONCLUSIONS: Familial forms make up approximately 10% of the series. We do not have any data available for early diagnosis nor for prognostic significance of familial MS.  相似文献   

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This case-control study was aimed at identifying environmental risk factors for multiple-sclerosis (MS). Ninety-three Israeli-born MS patients identified in country-wide studies and 94 age- and sex-matched controls were interviewed. The questionnaire covered a large span of factors at ages 0, 10 and onset of the disease, with particular emphasis on socioeconomic status (SES) and sanitary conditions (SAN). A significantly larger percentage of patients reported frequent respiratory educational levels than controls. The SES and SAN at age 10 were also systematically higher among patients, but significance was reached only when the frequencies of conditions indicating extremely low values of SES or SAN were compared. It is possible that the protective effect of low SES or SAN on risk of MS can be detected only when living conditions are well below average, as is frequent in developing countries.  相似文献   

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Magnetic resonance imaging (MRI) has provided considerable insight into the pathological process and disease activity and progression in multiple sclerosis. MRI has become an important tool for the diagnosis of multiple sclerosis, and increasingly for monitoring treatment trial. The growing use of MRI calls for careful consideration in applications so that the technology is not misused. Here we propose a summary of the literature on MRI in application in clinical neurology.  相似文献   

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OBJECTIVE: The authors sought to determine acute ambulatory- and hospital-billed charges for the Olmsted County, Minnesota Multiple Sclerosis (MS) Disability Prevalence Cohort and compare them to those incurred by the general population. METHODS: Billed charges for 155 people with clinically definite or laboratory-supported MS were compared with those of age- and gender-matched non-MS controls. Billing data, including all inpatient and outpatient acute and rehabilitative medical care charges over a 5-year period surrounding a December 1, 1991 prevalence date, were analyzed. Data were correlated with level of disability using the Minimal Record of Disability for MS. RESULTS: Median total annual billed charges for most individuals with MS, including those with less severe ($1,277) and relapsing-remitting illness ($1,348), did not differ from those for controls ($1,327, p=0.075). Only those with severe MS (22.6%) had median annual medical charges higher than controls ($5,440, p < 0.001). Male patients with MS had higher median annual total charges ($2,353) than male controls ($762, p=0.003). Total charges for female patients with MS ($1,440) were not different from those for female controls ($1469). Median annual outpatient charges were 15% more for the MS group ($1,418) than for controls ($1,231). Patients with MS had a mean of 0.2 hospital admissions annually compared with 0.1 annual admissions per control patient. Among variables collected on persons with MS, the Expanded Disability Status Scale was the strongest predictor of level of charges (p < 0.001). CONCLUSION: Acute ambulatory- and hospital-billed charges for most patients with MS do not differ from those of the general population.  相似文献   

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In a 6-year longitudinal study of a patient with relapsing progressive multiple sclerosis (MS), we used proton magnetic resonance spectroscopy to assess N-acetylaspartate (NAA) from a large central brain volume to evaluate the relationship between this marker of neuronal integrity and clinical disability. During the follow-up period, there was one major relapse and its subsequent partial remission. Changes in the brain NAA to creatine ratio correlated strongly with clinical disability (Spearman rank coefficient = -0.73, p < 0.001). We interpret this as evidence that axonal dysfunction or loss contributes to functional impairment of patients with MS. Because the NAA signal in the large volume of interest originated predominantly from white matter that appeared normal on conventional MRI, these results also suggest that some degree of axonal dysfunction may be widespread in acute, severe relapses.  相似文献   

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OBJECTIVE: To report the occurrence, type, causes, and management of psychiatric manifestations in multiple sclerosis (MS). METHOD: Review of recent, relevant literature. RESULTS: Psychiatric illness, especially depression, occurs much more frequently than expected in patients with MS, is frequently unrecognized or ignored, and is treatable using standard methods, although patients with MS may be unusually sensitive to side effects of tricyclic antidepressants. CONCLUSIONS: Research is needed to better define the causes of psychiatric syndromes in patients with MS. Those treating MS should increase their awareness of and sensitivity to the likelihood of psychiatric disorder in these patients.  相似文献   

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Multiple sclerosis (MS) has long been recognised to have both a relapsing-remitting and progressive course. More recently patients with progressive disease have been further sub-divided into those with a progressive course from onset (primary progressive MS) and those with progressive decline following an initially relapsing-remitting period (secondary progressive MS). Diversity in MS may not however be restricted to clinical course. There is growing evidence that the subgroups of MS also differ with respect to clinical features, epidemiology, pathogenesis, genetics and neuroimaging appearances. In this review we outline the criteria variously applied in the classification of MS patients, addressing the need for a clear nomenclature. We evaluate the proposition that primary progressive MS has a profile distinct from other MS categories, contrasting the separate differential diagnoses and examining the implications for future therapeutic trials.  相似文献   

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A comprehensive screening program was initiated in Saudi Arabia in 1982 to determine the frequency of the sickle cell (Hb S) gene in the different regions of Saudi Arabia. Over a period of 10 years 30,055 samples were collected from 36 areas in the five provinces of Saudi Arabia; these were screened using electrophoretic techniques in alkaline and acid pH for the presence of Hb S in heterozygous and homozygous states. The overall prevalence of Hb AS was 7.36% and Hb SS was 1.06%, giving an Hb S gene frequency of 0.047. The results from the different regions were separated and the prevalence of Hb AS and Hb SS and Hb S gene frequencies were calculated in each province and each region. The prevalence of Hb AS and Hb SS cases ranged from O to 25.88% and O to 5.27%, respectively. No case of Hb AS or Hb SS were identified in certain areas of the central province (Al-Russ, Al-Unaiza, Al-Mesnab and Bkaria) and northern province (Qurayat and Al-Jouf). In the southern province both Hb S homozygotes and heterozygotes were encountered in all regions except Farasan Island. In all other regions the Hb S gene was encountered, but at a variable frequency. Applying Hardy-Weinberg equilibrium it was observed that in the majority of the regions the observed Hb S homozygotes were significantly higher compared to the number expected (p < 0.0001). This was believed to be due to bias as the samples were collected in the hospital. The Hb S gene frequency in the different regions ranged from 0 to 0.17 when the frequency was calculated on the basis of both Hb AS and Hb. SS cases, and 0 to 0.13 if the gene frequency was calculated after eliminating the Hb SS cases. A close correlation was observed between the Hb S gene frequency and malaria endemicity. This study shows that the Hb S gene occurs frequently in several regions of Saudi Arabia and there is an urgent need to implement control and prevention programs to reduce the number of Hb S homozygous cases.  相似文献   

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OBJECTIVE: To conduct a prospective assessment of pregnancy on women with multiple sclerosis (MS), focusing on pregnancy outcome and relapses during gestation and up to 6 months after delivery. DESIGN: Expected numbers of relapses were based on data for (1) "self-controls": the mothers ("cases") themselves prior to becoming pregnant and (2) "matched controls": female patients with MS "matched" to the mothers for year of birth, age of MS onset, MS type, MS course, and initial MS symptom(s). SETTING: Cases and controls were identified from an ambulatory care MS clinic that serves the province of British Columbia, Canada. PATIENTS OR OTHER PARTICIPANTS: Women with a diagnosis of MS who attended the MS clinic during 1982 through 1986 and subsequently became pregnant during 1982 through 1989 inclusive were included in this study as cases. Matched controls were women with MS who attended the MS clinic during the same period but did not become pregnant. RESULTS: No significant increase in relapse rate was found for cases during the first two trimesters of gestation. The number of relapses was significantly less than expected during the third trimester compared with matched controls (chi 2 = 6.80, df = 1, P < .02), but not compared with self-controls (chi 2 = 3.39, df = 1, P > .05). The observed number of relapses for the 6 months after delivery did not differ significantly from expected (self-controls: chi 2 = 2.84, df = 2, P > .05; matched controls: chi 2 = 1.76, df = 2, P > .05). CONCLUSION: These data suggest that neither pregnancy nor the 6-month period after delivery is a risk factor for relapse in MS. They are consistent with previous observations that, in the long term, pregnancy does not influence subsequent MS disability.  相似文献   

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Nitric oxide (NO) is receiving interest because of its use in patients with acute respiratory distress syndrome. Because more studies are being conducted, researchers are discovering a vast array of physiological effects attributable to NO. NO has been implicated as having a role in the endogenous regulation of blood pressure; smooth, skeletal, and cardiac muscle relaxation; renal and immune system functioning; and selective pulmonary vasodilation. This article looks at the pharmacological and physiological effects of NO and its current use in the clinical setting.  相似文献   

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Neuroimaging in multiple sclerosis is now dominated by MR imaging. This article will focus primarily on conventional MR imaging studies in multiple sclerosis, but will also discuss briefly some of the more recent advances related to MR imaging. Fast spin-echo imaging, fluid attenuated inversion recovery MR studies, three-dimensional volumetric studies, magnetization transfer, and magnetic resonance spectroscopy as it applies to multiple sclerosis are examined.  相似文献   

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Prognosis of the natural course of multiple sclerosis is most often measured on Kurtzke's "expanded disability status scale" (EDSS), a non-linear scale over 20 steps, heavily weighted on mobility. Optic neuritis and sensory disturbances as initial symptoms, lower age at onset of the disease, female sex and a longer interval between relapses are indicators of a more favorable prognosis. As a rule, disability as measured on this scale 5 years after onset corresponds to 3/4 of the disability status after 15 years. The number of relapses diminishes naturally over the course of the disease. Presence and extent of lesions on the initial MRI of the brain in clinically isolated syndromes are valuable predictors of dissemination of the disease process over the following 5-10 years. New therapies (e.g. interferon beta 1b and 1a, copolymer 1) reduce relapse frequency by 1/3 and diminish the extent of pathological lesions in brain MRI, but fail to show (as yet) significant influence on disability.  相似文献   

19.
Multiple sclerosis begins before the age of 17 years in 0.4 to 0.5% of the cases, but the diagnosis is exceptionally made before the age of 10 years. Female predominance is more marked in early onset multiple sclerosis. The general features of the disease (clinical expression, progression, prognostic) and the findings of complementary explorations are comparable with those found when the disease begins in adulthood although acute onset and signs of brain stem involvement have been reported. The diagnosis must be made with prudence, especially when progression is slow from the beginning. An analysis of the influence of infective environmental factors and puberty has not provided new insight. Corticosteroids can be used in case of flare-ups. Management requires a multidisciplinary approach to maintain appropriate educational activities.  相似文献   

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