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21.
An 8 year old girl with acute disseminated encephalomyelitis (ADEM) is described. Elevated serum antibody titers suggested recent Mycoplasma pneumoniae infection. T2-weighted image of magnetic resonance imaging (MRI) disclosed multiple lesions of high signal intensity in bilateral basal ganglia and thalami as well as in the white matter. Postcontrast T1-weighted image revealed an enhanced lesion in the deep white matter. She showed rapid clinical improvement in response to corticosteroid therapy. The lesions had disappeared completely on MRI performed 10 weeks after the onset. ADEM is believed to be a demyelinating disorder of probable autoimmune etiology. MRI findings in this case may support the hypothesis that the primary pathological event is vascular injury and demyelination occurs only as a secondary phenomenon.  相似文献   
22.
The purpose of the present study was to clarify the developmental changes of electroencephalogram (EEG) background activity in term and preterm infants that take place with increasing conceptional age (CA) through an autoregressive (AR) model. Polygraphical EEG recordings were obtained from 76 healthy term and preterm infants with a CA ranging between 31 and 40 weeks. Decreases in total power and component power of δ were noted with CA during burst activity (BA) in quiet sleep (QS) and during active sleep (AS). Increases in total power and component power of δ were noted with CA during interburst interval activity (IBIA) of QS. Regression analysis (RA) of the information amount (IA) indicated a negative correlation with increasing CA in AS and in the monopolar EEG tracings Fp1, C3, O1 and O2 in BA, and a positive correlation in O1 in IBIA. Regression analysis of the IA of δ indicated a negative correlation with increasing CA in AS and in Fp1, C3, O1 and O2 in BA, and a positive correlation in O1 in IBIA. Regression analysis of the IA of δ indicated a negative correlation with increasing CA in BA and AS. These results showed that the high voltage slow wave component changed to a low voltage slow one with development in AS and that BA was longer in duration and lower in power with increasing CA, while IBIA was shorter in duration and higher in power. In conclusion, significant developmental changes occur in all derivatives of AS. Even though the EEG of BA and IBIA change separately, they are followed by EEG of QS in a continuous pattern.  相似文献   
23.
Summary. The ratio of serum pregnancy-specific β1-glycoprotein (SP1) to the β-subunit of human chorionic gonadotrophin (β-hCG) before and after chemotherapy was measured in 12 patients with metastatic choriocarcinoma. The ratios before chemotherapy ranged between 0.03 and 0.75, with a mean value of 0.34 (SD 0.21). The ratio increased to over 1.0 (1.05–53.3) after one or two courses of chemotherapy in seven of the 12 patients. These women achieved complete remission. In the other five patients who died of the disease due to drug resistance of the tumour, the ratio after chemotherapy was low (0.04–0.74) and tended to decline. These data suggest that the serum SPl/β-hCG ratio can be used to predict the prognosis of patients with choriocarcinoma.  相似文献   
24.
A female infant with 21 trisomy syndrome associated with congenital chylothorax was reported. She was born at a gestational age of 34 weeks by Cesarean section because of fetal hydrothorax and hydrops fetus, confirmed by ultrasonography at 32 weeks. Emergent resuscitation and immediate thoracentesis were performed soon after birth. After beginning breast feeding, the serous pleural fluid became opalescent and a diagnosis of congenital chylothorax was made. Feeding was changed to medium-chain triglyceride (MCT) feeding and the production of pleural effusion disappeared after thoracentesis was performed several times. Accumulating evidence suggested that MCT feeding and intermittent thoracentesis under echo guide were effective. Some reports on patients, including this one, suggest that there may be more patients with 21 trisomy associated with congenital hydrothorax. Therefore, congenital hydrothorax might be listed as a complication of 21 trisomy.  相似文献   
25.
Diffuse antral vascular ectasia and a lla type early gastric cancer were detected in an 83-year-old male patient through an endoscopy during treatment for iron deficiency anemia. Monopolar electrocoagulation was effective for eradication of red spots which represented ectatic vessels. Five sessions of the therapy resulted in the ablation of almost all of the vascular lesions, negative fecal occult blood tests and improvement of his anemia. The lla lesion was endoscopically resected from the posterior wall of the upper body. Histologic examination demonstrated well differentiated adenocarcinoma confined to the mucosal layer. Both the vascular ectasia and carcinoma did not show any sign of recurrence after a year and a half.  相似文献   
26.
Objective: Although enterobacteria are implicated in intestinal immune response, there has been no report on how intraluminal pathogens affect lymphocyte recruitment. The aim of this study was to determine how the presence of intestinal flora affects lymphocyte migration to intestine under physiological and lipopolysaccharide (LPS)‐induced inflammatory conditions. Methods: Interaction of T‐cells with ileal microvessels was monitored by using an intravital microscope in mice under germ‐free (GF) and specific pathogen‐free (SPF) conditions. LPS was administered into either the peritoneal cavity or duodenum before lymphocyte injection. Results: Adherence of T‐cells was greater in SPF than in GF mice, indicating that the presence of enterobacteria upregulated migration under physiological conditions. Intraperitoneally administered LPS significantly increased the adherence of T‐cells in both GF and SPF mice accompanied by the expression of adhesion molecules and proinflammatory cytokines. However, intraluminally administered LPS did not enhance the adherence of T‐cells in SPF mice. A significant induction of increase in mRNA expression of IRAK‐M, a negative regulator of TLR4 signaling, and transforming growth factor beta (TGF‐beta), a regulatory cytokine, was observed in SPF mice after luminal LPS treatment. Conclusions: Tolerance to intraluminally administered LPS in the lymphocyte recruitment process was induced by enterobacteria, possibly via the induction of IRAK‐M and TGF‐beta.  相似文献   
27.
Abstract: We report a patient with an asymptomatic recurrent peptic ulcer occurring in the gastric tube after reconstruction for esophagectomy with a long follow-up. The patient is an 82-year-old male, who had undergone an esophagectomy for cancer, and a gastric tube was used for esophageal replacement at the age of 77 years. A follow-up study using endoscopic examination revealed an active peptic ulcer in the gastric tube one year after the operation, ulcer scar formation 9 weeks after H2 receptor antagonist medication, and recurrence of the ulcer about 3 years after quitting the medication. The recurrent active ulcer has disappeared after re-administration of H2 receptor antagonist. Helicobacter pylori has not been detected, although eradication has not been per formed. It is suggested that high acidity might play a part in the pathogenesis of ulcer formation despite the vagotomy. Since a peptic ulcer in the gastric tube can potentially cause serious complications including perforation and hemorrhage, we have to bear in mind not only recurrence of the cancer but also gastric tube ulceration in the follow-up survey after esophagectomy, to facilitate early detection of ulcer and effective treat ment. (Dig Endosc 1999:11: 62–65)  相似文献   
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29.
In case-control studies of complex disease genes, allele frequencies or allele positivities at candidate loci or markers are compared between cases and controls. Although 2 × 2 contingency tables based on allele frequency and allele positivity are generally used to perform simple statistical tests (e.g. a comparison of two proportions and a χ2 test), little is known about the difference in power between the two tables. In this study, we investigated the number of subjects required to obtain a power of 1 −β with a significance level of α for the allele frequency and allele positivity tables. A large difference in the required number of subjects was found between the two tables. Allele positivity tables were suitable for the detection of susceptibility alleles showing a dominant mode of inheritance (MOI). On the other hand, allele frequency tables were suitable for the identification of susceptibility alleles showing a recessive MOI or a multiplicative MOI. In the case of an additive MOI, a suitable table was determined by combining the frequency of the susceptibility allele and the penetrance. These results imply that there are cases in which true association is detected based on one contingency table and is not detected based on another. A simulation analysis revealed that the type I error rate was not much inflated under the null hypothesis of no association, even when a statistical test was performed twice using both allele frequency and allele positivity tables. In contrast, under the alternative hypothesis, the loss of power was marked when a test was performed once using an unsuitable table. In conclusion, statistical tests should be performed using both tables, without adjustment of multiplicity, in case-control studies of complex disease genes when the study objective is exploratory.  相似文献   
30.
A series of eight patients in a persistent vegetative state (PVS) were subjected to chronic deep brain stimulation (DBS) for the purpose of promoting recovery from the PVS. The characteristics of the brain activity in these patients were evaluated from the late positive component of the cerebral evoked potential in response to painful stimuli (pain-related P250). While any neurological scoring system for the comatose state includes evaluations of motor reactions to painful stimuli, the pain-related P250 is unique in terms of its ability to assess the cortical responsiveness to painful stimuli directly and quantitatively without involving functions of the motor system. It was found that the pain-related P250 was more or less depressed in patients in a PVS. It was repeatedly demonstrated in four patients, however, that the pain-related P250 could be transiently increased by preceding stimulation of the mesencephalic reticular formation. Furthermore, a persistent increase in the pain-related P250 was produced in these four patients following chronic DBS of the mesencephalic reticular formation or nonspecific thalamic nuclei for more than 6 months, and this was correlated with the clinical improvements. These results imply that responsiveness at the cortical level to pain is depressed in the PVS. It also appears that some fraction of the depression may, however, be functionally produced and potentially reversible.  相似文献   
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