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1.
A promising treatment method for type 1 diabetes mellitus is transplantation of pancreatic islets containing beta-cells. The aim of this study was to develop an MR technique to monitor the distribution and fate of transplanted pancreatic islets in an animal model. Twenty-five hundred purified and magnetically labeled islets were transplanted through the portal vein into the liver of experimental rats. The animals were scanned using a MR 4.7-T scanner. The labeled pancreatic islets were clearly visualized in the liver in both diabetic and healthy rats as hypointense areas on T2*-weighted MR images during the entire measurement period. Transmission electron microscopy confirmed the presence of iron-oxide nanoparticles inside the cells of the pancreatic islets. A significant decrease in blood glucose levels in diabetic rats was observed; normal glycemia was reached 1 week after transplantation. This study, therefore, represents a promising step toward possible clinical application in human medicine.  相似文献   
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By means of injecting soot into the vessels of the uveal tract of the rabbit eye the character of changes in the architectonics of the vascular bed in dynamics of the burn process could be detected. It was found that a burn trauma produces changes in practically the whole uveal tract, but to a greater extent, in its anterior segment. Reduction of blood filling of the vessels or their total segmentary "switching-off" is connected with the development of reversible (thrombosis, oedema of endotheliocytes and surrounding stroma, hemolysis) and irreversible (destruction of the vascular wall, obliteration of vessels) structural changes. The degree of disturbances in blood circulation and reversibility of these changes depend on the severity of the burn. In case of less severe burns, total structural restoration of the vascular network in the nearest time is recorded, while in severe burns--partial restoration with elements of vascular net reconstruction of adaptive character.  相似文献   
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The purpose of the current study was to investigate the role of visual information on gait control in people with Parkinson's disease as they crossed over obstacles. Twelve healthy individuals, and 12 patients with mild to moderate Parkinson's disease, walked at their preferred speeds along a walkway and stepped over obstacles of varying heights (ankle height or half-knee height), under three visual sampling conditions: dynamic (normal lighting), static (static visual samples, similar to stroboscopic lighting), and voluntary visual sampling. Subjects wore liquid crystal glasses for visual manipulation. In the static visual sampling condition only, the patients with Parkinson's disease made contact with the obstacle more often than did the control subjects. In the successful trials, the patients increased their crossing step width in the static visual sampling condition as compared to the dynamic and voluntary visual sampling conditions; the control group maintained the same step width for all visual sampling conditions. The patients showed lower horizontal mean velocity values during obstacle crossing than did the controls. The patients with Parkinson's disease were more dependent on optic flow information for successful task and postural stability than were the control subjects. Bradykinesia influenced obstacle crossing in the patients with Parkinson's disease.  相似文献   
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Objective: To evaluate the perinatal results from epileptic women using antiepileptic drugs during prenatal care.

Methods: This was a retrospective longitudinal study assessing the perinatal results of women exposed to antiepileptic drugs during pregnancy, and we compared these results with those of pregnant women who were not exposed. The development of pregnancy, gestational age at delivery, Apgar scores, biometric data, morbidity, stillbirths and neonatal mortality were analyzed. The chi-square test and Fisher’s exact test were used for the categorical variables, while Student’s t-test was used for independent numerical variables.

Results: Over a 10-year period, 12?790 singleton gestations were analyzed, among which 104 (0.8%) consisted of epileptic pregnant women. From this total, 82 evolved to childbirth and their neonatal data were compared with those of 316 newborns from non-epileptic women. The most-used antiepileptic drug was phenobarbital in 70% of the cases. There was greater neonatal mortality (p?=?0.006), occurrence of neonatal hemorrhagic disorders (p?=?0.005), and occurrence of minor congenital anomalies (p?=?0.03) among the children of women exposed to antiepileptic drugs.

Conclusion: The antenatal exposure to antiepileptic drugs is associated mainly with occurrences of hemorrhagic complications during the neonatal period; furthermore, great prevalence of newborns presenting minor congenital anomalies and elevated risk of neonatal mortality.  相似文献   

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Human visceral (VL, also known as Kala-azar) and cutaneous (CL) leishmaniasis are important infectious diseases affecting countries in East Africa that remain endemic in several regions of Ethiopia. The transmission and epidemiology of the disease is complicated due to the complex life cycle of the parasites and the involvement of various Leishmania spp., sand fly vectors, and reservoir animals besides human hosts. Particularly in East Africa, the role of animals as reservoirs for human VL remains unclear. Isolation of Leishmania donovani parasites from naturally infected rodents has been reported in several endemic countries; however, the status of rodents as reservoirs in Ethiopia remains unclear. Here, we demonstrated natural Leishmania infections in rodents. Animals were trapped in 41 localities of endemic and non-endemic areas in eight geographical regions of Ethiopia and DNA was isolated from spleens of 586 rodents belonging to 21 genera and 38 species. Leishmania infection was evaluated by real-time PCR of kinetoplast (k)DNA and confirmed by sequencing of the PCR products. Subsequently, parasite species identification was confirmed by PCR and DNA sequencing of the 18S ribosomal RNA internal transcribed spacer one (ITS1) gene. Out of fifty (8.2%) rodent specimens positive for Leishmania kDNA-PCR and sequencing, 10 were subsequently identified by sequencing of the ITS1 showing that five belonged to the L. donovani complex and five to L. tropica. Forty nine kDNA-positive rodents were found in the endemic localities of southern and eastern Ethiopia while only one was identified from northwestern Ethiopia. Moreover, all the ten ITS1-positive rodents were captured in areas where human leishmaniasis cases have been reported and potential sand fly vectors occur. Our findings suggest the eco-epidemiological importance of rodents in these foci of leishmaniasis and indicate that rodents are likely to play a role in the transmission of leishmaniasis in Ethiopia, possibly as reservoir hosts.  相似文献   
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The present study had three objectives: (a) to characterize the functional capacity of patients with PD, (b) to assess the relationship between the physical fitness components of functional capacity with clinical characteristics and disease severity, and (c) to compare the physical fitness components of functional capacity with clinical characteristics according to disease severity. The study included 54 patients with idiopathic PD who were distributed into two groups according to PD severity: unilateral group (n=35); and bilateral group (n=19). All patients underwent psychiatric assessment by means of the Hoehn and Yahr (HY) staging of PD, the Unified Parkinson's Disease Rating Scale (UPDRS), the Hospital Anxiety and Depression Scale (HADS-A and HADS-D, respectively), and The Mini-Mental State Examination (MMSE). The physical fitness components of functional capacity were evaluated over a 2-day period, using recommendations by the American Alliance for Health, Physical Education, Recreation and Dance, and the Berg Balance Scale (BBS). Pearson correlation coefficients and multiple regressions were calculated to test the correlation between functional capacity and clinical characteristics, and to predict clinical scores from physical performance, respectively. Clinical variables and physical component data were compared between groups using analysis of variance to determine the effects of disease severity. Patients with advanced disease showed low levels of functional capacity. Interestingly, patients with good functional capacity in one of the physical fitness components also showed good capacities in the other components. Disease severity is a major factor affecting functional capacity and clinical characteristics. Medical providers should take disease severity into consideration when prescribing physical activity for PD patients, since the relationship between functional capacity and clinical characteristics is dependent on disease severity.  相似文献   
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