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971.
Acholeplasmas have been isolated from a variety of animals, insects, and plants, but onlyAcholeplasma laidlawii has previously been found in humans. We have isolatedAcholeplasma oculi in pure culture from the amniotic fluid of a woman at 19 weeks of gestation. The organism was positively identified by growth inhibition, epi-immunofluorescence, and arbutin hydrolysis. Demonstration of organisms directly in amniotic fluid by DNA fluorochrome and immunofluorescence staining provided additional evidence that the isolate was genuine and not a medium contaminant. The remainder of the pregnancy was unremarkable, and a full-term male infant was delivered without complications. Even though there is some evidence possibly associatingA. oculi with various diseases in livestock, the prevalence and significance ofA. oculi in humans has not been determined.  相似文献   
972.
Auto anti-A1 and auto anti-NA1 after bone marrow transplantation   总被引:1,自引:0,他引:1  
The production of auto anti-A1 and auto anti-NA1 antibodies in patient with aplastic anemia has been described. The patient of group A1 received bone marrow from his brother of group A2. For immunosuppression cyclosporine A was administered.  相似文献   
973.
The experimentally observed influence of regularly arriving tugs upon the AP discharge of the slowly-adapting stretch receptor organ (SAO) of crayfish was compared to a model of pacemaker excitatory synaptic interactions (Segundo and Kohn 1981). Criteria for compliance referred to facets as A) the excitation, B) the postulates, and C) the behavior. A) Excitation was implied primarily by the tug initially increasing the AP rate (it subsequently decreased it). B) The pacemaker AP discharges, and with more reason the electronically driven tugs, were considered acceptably regular sequence (postulate i). Tugs advanced the next AP (postulate ii); the "delay function" plots of delays vs. phases, i.e. interval shortenings vs. the time from the last AP to the tug, were close to the V of postulate iii, even though the shortest phases tended to postpone the next AP and the longest ones did not trigger immediately but with an around 5 ms latency. These effects were displayed also as "old phase vs. new phase" plots. The interval following that with the tug tended to be lengthened, but the pre-tug timing was not recovered. C) Behavior during a train of excitatory events, both in model and experiments, went through very similar initial settlings and eventual steady-states. The latter were characterized in the model by 1. an average excitatory vs. excited rate display formed by an endless number of segments with all positive rational slopes separated by negative-going discontinuities, 2. locking in the sense of preferential phases, and 3. periodic repetition of the same phases and inter-AP intervals. Experimental results were compatible with this. Such behavior was absent when the tug sequence was highly irregular. The initial settling, in the SAO as in the model, depended jointly on the first phase phi 1 and the intertug interval E. If the former was under lambda, it went through one or two monotonic phase-decreasing stages (one smaller, the other larger, than lambda), or through a single increasing one, depending on E being smaller or greater than, respectively, an estimated but never actually observed E leading to unstable lockings. If the initial phase was greater than lambda, settling with E's under rN + lambda involved jumps between larger than and smaller than lambda phases; with E's over rn + lambda, it involved an intermediate stable locking with phi = E-rN.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
974.
Summary Skin tests with autologous cholesteryl hemisuccinate (CHS)-treated and untreated cells were performed in ten metastatic melanoma patients. In the majority of cases evident reaction was noted with CHS-treated cells (9/10) while the reaction with untreated cells was mostly negative (7/10). Tumour cell suspensions used for skin tests were characterized for reactivity with monoclonal antibody TAL 1B5 detecting the HLA-DR alpha chain. There were no differences between CHS-treated and untreated cells with respect to HLA-DR expression and no correlation was found between grade of skin reaction to CHS-treated cells and the proportion of HLA-DR positive cells in the injected cell sample.  相似文献   
975.
The aim of this study was to investigate whether the rapid improvement of the clinical condition of patients after administration of nitroglycerin can be documented objectively using the apexcardiogram. The study was performed on 28 male patients with coronary heart disease whose clinical condition allowed us to perform the initial polygraphic examination during an attack of angina pectoris. The heart rate and three apexcardiographic indexes were determined from non-invasive polygraphic tracings. The first index was the a/H (ratio: amplitude of apexcardiographic "a" wave to total amplitude of apexcardiogram). The second and third were the velocity of the anterior left ventricular wall motion during both isovolumic contraction (VwmC) and isovolumic relaxation (VwmR) of the left ventricle. The mean differences from initial values were calculated after 2, 4, 6 and 10 min following administration of nitroglycerin. Significant changes already occurred during the second minute after administration of nitroglycerin. All parameters remained significantly changed up to the 10th minute after this treatment. According to our results, the cardiovascular response to sublingual administration of nitroglycerin can be objectively evaluated by apexcardiography.  相似文献   
976.
The effect of an antioxidant dibunol and calcium antagonist verapamil on postperfusion release of myoglobin (Mb) and MB-creatine kinase (MB-CK) has been assessed in 30 dogs with experimental coronary occlusive myocardial infarction. It has been shown that reperfusion after 3-hour ischemia does not only accelerate the release of intracellular proteins, but also leads to pronounced myoglobinemia and blood enzymes. In postischemic blood flow recovery with combined dibunol and verapamil preliminary injections, an almost threefold decrease in MB-CK and Mb blood content, as compared to "reperfusion" indexes, was observed by the 10th minute of reperfusion.  相似文献   
977.
Quantitative deoxyribonucleic acid (DNA) analysis of cervical biopsy specimens from 26 women with cytological, colposcopic, and histological evidence of mild cervical atypia consistent with cervical intraepithelial neoplasia grade I, reactive atypia, or human papillomavirus infection alone or in combination was performed in a comparative evaluation of Feulgen microspectrophotometry, the fast interval processor image analysis system, and flow cytometry. The fast interval processor image analysis system showed a distinct advantage over the other methods, being faster and allowing the operator to see the cells that were selected for measurement. The three methods of measurement together showed that the DNA content of at least 2% of the cells measured exceeded 5C (C being the haploid amount of DNA in a normal cell and 2C representing the diploid complement of a normal cell) in all cases of cervical intraepithelial neoplasia grade I and reactive atypia and in 87% of those reported as showing human papillomavirus infection alone. In contrast, the DNA content of cervical biopsy specimens from the transformation zone of 11 normal controls did not exceed 4C. This study shows the value of using a DNA threshold--that is, the "5C exceeding rate"--to distinguish between normal and neoplastic appearances of the cervix. These results support the view that cervical infection by human papillomavirus is a true precursor of neoplasia.  相似文献   
978.
In a randomised, double blind, long term, crossover study 1 g twice daily of methenamine hippurate was compared with placebo for its preventive effect on recurrent attacks of acute cystitis. Methenamine hippurate and placebo were interchanged every six months for two years. During one of the years patients took 250 ml extra fluid every morning and evening. Out of 21 enrolled patients, 14 completed the first year and 13 both years of treatment, which permitted the evaluation of 27 patient years. There were 52 episodes of acute cystitis caused by reinfection: 41 occurred during placebo treatment and only 11 during the methenamine hippurate regimen (p less than 0.01). Extra fluid intake did not reduce the incidence of acute cystitis, nor did it reduce the effect of methenamine hippurate. Methenamine hippurate is an effective prophylactic agent against recurrent acute cystitis and has the advantage of not inducing cross resistance to conventional antibiotics.  相似文献   
979.
A total of 276 sequential serum samples from 34 men with antibodies to the human immunodeficiency virus (HIV) followed up for two to seven years were analysed for HIV antigen and antibodies to the viral core and envelope proteins. Results were correlated with clinical outcome and CD4 T lymphocyte count. Both antigenaemia and the disappearance of antibodies to the core protein were associated with development of the acquired immune deficiency syndrome (AIDS) or AIDS related complex and depletion of CD4 cells. Thus AIDS or AIDS related complex developed in eight out of 16 patients with antigenaemia compared with one out of 18 patients without antigenaemia. Low counts of CD4 cells (less than 0.5 X 10(9)/l) were found in 14 of the 16 patients with antigenaemia and five of the 18 without antigenaemia. Nine patients seroconverted to HIV during the study; two of these developed antigenaemia 14 and 16 months after the estimated time of seroconversion. These results show that the late stages of HIV infection are characterised by increased production of antigen and a decrease in antibodies directed against the core protein. Antigenaemia indicates a poor prognosis; and as the antigen test is simple to do and interpret, it may therefore be useful for selecting patients for antiviral treatment.  相似文献   
980.
Recurrent cyanotic episodes associated on some occasions with loss of consciousness due to cerebral hypoxia were investigated by long term tape recordings of breathing activity, oxygen saturation, air flow, electrocardiographic activity, and in some cases electroencephalographic activity. In 51 infants and children the mechanisms for the cyanotic episodes were identified (prolonged expiratory apnoea in 45, sleep related airway obstruction in three, seizure induced apnoea in one, behaviour induced apnoea in one). In one child apnoea was suspected as being caused by suffocation (smothering) by the mother. This was confirmed after enlisting the help of the police, who undertook covert video surveillance during cyanotic episodes. Each cyanotic episode was associated with a pattern of disturbance on the multichannel tape recordings which may be pathognomonic of this type of apnoea. A second infant with cyanotic episodes in whom smothering was suspected was referred for similar investigation after the availability of video recordings became established. Maternal smothering was again supported by specific patterns on multichannel tape recordings and confirmed by video surveillance. Diagnosis by video surveillance produces unequivocal evidence in these cases and avoids the need for medical and nursing staff to confront the mother with a possibly incorrect suspicion or in a court of law.  相似文献   
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