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991.
Objective To determine the occurrence of neurological changes during the first 48 hours after acute stroke as it relates to the initial stroke severity assessment. Methods The assessment with the National Institutes of Health Stroke Scale (NIHSS) was performed serially for the first 48 hours on 68 consecutive ischemic stroke patients admitted to the Department of Geriatric Cardiology at the Khanh Hoa Hospital, Nha Trang, Vietnam. Incidence of stroke progression (a ≥ 3-point increase on the NIHSS) was recorded and analysis performed to determine its association with initial stroke severity and other demographic and physiological variables. Deficit resolution by 48 hours, defined as an NIHSS score of 0 or 1, measured the frequency of functional recovery predicted by the initial deficit. Results Overall progression was noted in 28% of events (19/68). Applying Bayes' solution to the observed frequency of worsening, the greatest likelihood of predicting future patient progression occurred with NIHSS score of =7 and >7. Patients with an initial NIHSS score of =7 experienced a 13% (6/47) worsening rate versus those of an initial score of >7 with a 62% (13/21) worsening rate (P<0.01). 42.5% (20/47) of those with an initial score of =7 were functionally normal at 48 hours, whereas only 4.7% (1/21) of those with scores of >7 returned to a normal examination within this period (χ2, P<0.05). Conclusions This study suggests that the early clinical course of neurological deficit after acute stroke be dependent on the initial stroke severity and that a dichotomy in early outcome exist surrounding an initial NIHSS score of 7. These findings may have significant implications for the design and patient stratification in treatment protocols with respect to primary clinical outcome.(J Geriatr Cardiol 2007;4:225-228.)  相似文献   
992.
Many medical schools still use oral examinations for the evaluation of clinical competence of students in their clerkship, although it has been proven that orals have poor reliability. This study investigates the feasibility and reliability of multiple oral examinations. Students in the last week of their Internal Medicine clerkship in an outpatient clinic were given several patient-based oral examinations. The student's performance was rated on a list of items reflecting clinical competence. A global judgement of the student's performance was also given. The results indicate that it is possible to increase the number of orals and the number of examiners in the day-to-day practice of an outpatient clinic moderately. The reliability when using a number of orals is better than the reliability of the common single oral examination. The reliability using global judgements appeared to be better than the reliability of averaged item scores.  相似文献   
993.
Bioassay-guided fractionation of the dichloromethane extracts of the roots and the bark of Zanthoxylum usambarense led to the isolation of two physiologically active compounds, i.e. canthin-6-one 1 (fungicide) and pellitorine 4 (insecticide). Together with oxychelerythrine 2, norchelerythrine 3, (+)-sesamin 5 and (+)-piperitol-3,3-dimethylallyl ether 6, they were isolated for the first time from this plant.  相似文献   
994.
Autosomal recessive retinitis pigmentosa (ARRP) is a degenerative disorder of photoreceptors. Mutations in several genes encoding different proteins of the visual cascade are described. The inheritance of two intragenic markers within the interstitial retinol binding protein (IRBP) gene was established in 45 Spanish families with a history of ARRP. Homozygosity mapping and cosegregation analyses were positive in 19 families. Only one heterozygous T-C transition at position 3024 (exon 1) was detected in one consanguineous family. This variant was identified as a rare polymorphism and was present in 5% of the chromosomes analyzed.  相似文献   
995.
As a consequence of animal studies reduction of the light regimes have been tried on patients with retinitis pigmentosa. The trials have been very limited and have not given reason for hope that such reduced light therapy may be beneficial. However, RP patients trying red glasses have reported acute subjective improvement of their visual function. It was the purpose of this study to try to document the reports more objectively. Five visual functions were tested with and without red glasses with the following results: 1. Visual acuity and contrast sensitivity. For one volunteer a small reproducible improvement was found. 2. Color vision. In most cases deterioration was found of already deficient color vision. 3. Visual fields. For volunteers with relatively preserved vision no difference or slight deterioration was found. For the other volunteers slight improvements were found. 4. Intraocular light scatter. No differences were found. 5. Dark adaptation. Improvements were found when the glasses were used as adaptation aid according to the method of Trendelenburg (rod function). For cone function no difference was found upon continuous wearing of red glasses.In conclusion: use of red glasses does not seem to be of great benefit as a rule. On the other hand, apart from the reduction in color discrimination no serious disadvantages seem to be inherent in their wear by RP patients.  相似文献   
996.
997.
998.
Autonomic innervation of human and rat myometrium has been investigated using various histochemical methods. With all the methods used, rat myometrium shows a loosely interlacing network of bundles of nerve fibers, whereas in myometrium of the human fundus neither cholinergic nor adrenergic fiber bundles could be demonstrated. These findings are discussed in relation to the influence of the autonomic nerve fiber bundles on peristalsis.  相似文献   
999.
BackgroundMaternal death surveillance in Canada relies on hospitalization data, which lacks information on the underlying cause of death. We developed a method for identifying underlying causes of maternal death, and quantified the frequency of maternal death by cause.MethodsWe used data from the Discharge Abstract Database for fiscal years 2013 to 2017 to identify women who died in Canadian hospitals (excluding Quebec) while pregnant or within 1 year of the end of pregnancy. A sequential narrative based on hospital admission(s) during and after pregnancy was constituted and reviewed to assign the underlying cause of death (based on the World Health Organization's framework). Maternal deaths (i.e., while pregnant or within 42 days after the end of pregnancy) and late maternal deaths (i.e., more than 42 days to a year after the end of pregnancy) were examined separately.ResultsWe identified 85 maternal deaths. Direct obstetric causes included 8 deaths (9%) related to complications of spontaneous or induced abortion; 9 (11%), to hypertensive disorders of pregnancy; 15 (18%), to obstetric hemorrhage; 11 (13%), to pregnancy-related infection; 16 (19%), to other obstetric complications; and <5 (<6%), to complications of management. There were 21 (25%) maternal deaths with indirect obstetric causes, and <5 (<6%) with undetermined causes. Of 120 late maternal deaths, 16 (13%) had direct obstetric causes, among them, 9 deaths by suicide (56%). One hundred late maternal deaths (83%) had indirect obstetric causes; and <5 (<4%) had undetermined causes.ConclusionsThe majority of maternal deaths in Canada have direct obstetric causes, whereas most late maternal deaths have indirect obstetric causes. Suicide is an important direct cause of late maternal death.  相似文献   
1000.
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Changes in the potential and contractility of smooth muscle cells of guinea-pig taenia caeci were measured (22 degrees C) in order to investigate the effect of mebeverine, a derivative of beta-phenylethylamine, on alpha 1-receptor-operated ion channels in particular. Mebeverine (6 X 10(-6) M) showed atropine-like properties by shifting to the right the concentration-response curve obtained with carbachol. Hyperpolarization and cessation of spike activity of the muscle cells, accompanied by an increased amplitude of the electrotonic potential were observed in the presence of mebeverine (6 X 10(-5] after block of the alpha 2-, beta- and muscarinic receptors. This effect of mebeverine was not observed in low-sodium solution (23.8 mM), suggesting that mebeverine decreased sodium permeability. The alpha 1-receptor-induced hyperpolarization caused by adrenaline (3 X 10(-6) M) in the presence of mebeverine declined after reaching an initial maximum. The hyperpolarization induced by a second addition of adrenaline to the preparation was decreased and sustained in the presence of mebeverine, while the decrease of the electrotonic potential evoked during the alpha 1 response was less pronounced. The transient hyperpolarization representing the alpha 1 response in the absence of extracellular calcium developed more slowly in the presence of mebeverine, the area of the response being constant. When the experiment was continued in calcium-free solution after a short exposure to calcium-containing Krebs solution still in the presence of mebeverine, the alpha 1-receptor-induced hyperpolarization was suppressed.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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