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101.
A healthy 23-year-old man suffered helmet-to-helmet collisions with an opponent during American football game twice within 3 days. He then experienced continuous vomiting and dizziness. Magnetic resonance imaging revealed acute infarction in the right cerebellar hemisphere, and magnetic resonance angiography revealed transient stenosis of the right superior cerebellar artery. Although minor head injury is not usually accompanied by complications, posttraumatic ischemic stroke has been reported on rare occasions. We report a case of cerebellar infarction after repeated sports-related minor head injuries in a young adult and discuss the etiology.  相似文献   
102.
This retrospective study constitutes a part of the Japanese Registry of Neuroendovascular Therapy (JR-NET) 1 and 2. Its purpose is to evaluate the feasibility, safety, and outcome of endovascular embolization for cerebral arteriovenous malformations (AVMs) in Japan. Nine hundred and eighty-seven embolization procedures were registered with JR-NET 1 and 2 (424 procedures in 122 institutions with JRNET 1 and 563 procedures in 150 institutions with JRNET 2). In total, 790 patients (80.1%) had favourable clinical outcomes defined as modified Rankin Scale (mRS) scores 0–2 at 30 days after embolization. Complete AVM obliteration by embolization alone was achieved in 90 procedures (9.1%). The procedural morbidity and mortality rate was 2.5% and 0.3% per procedure, respectively. In the multivariate logistic regression models, deep venous drainage and embolization of four or more feeding pedicles per session were significantly associated with any treatment-related complications (P = 0.02 and P = 0.003, respectively). About 6 cm or more in maximum nidus diameter had a negative correlation with complications (P = 0.003). Our study shows that embolization of cerebral AVMs was performed with a high degree of safety and a low rate of symptomatic complications in Japan.  相似文献   
103.
Ventricular Rate During AF. Introduction: The mechanisms of the ventricular response during atrial fibrillation (AF) remain uncertain. The parameters obtained during an electrophysiologic study, including atrial rates during AF, were analyzed to clarify further the determinants of the ventricular rate during AF.
Methods and Results: Thirty patients without manifest preexcitation in whom AF was induced during electrophysiologic study were divided into two groups, Group I consisted of 20 patients (ages 55 ± 10 years) without a dual AV nodal pathway. Group 2 consisted of 10 patients (ages 53 ± 13 years) having a dual AV nodal pathway. The correlation coefficient between the mean RR interval during AF (mRR) and the mean intra-atrial potential interval during AF (mff) was positive (0.05 [P < 0.05] in group 1 and 0.37 [P = NS] in group 2). The correlation coefficient of the mRR against the functional refractory periods of the AV node (AVFRP) was 0.73 (P < 0.001) in group 1. The correlation coefficients between mRR and the fast AV nodal pathway functional refractory periods and the slow AV nodal pathway effective refractory periods (SPERP) were 0.58 (P = NS) and 0.7 (P < 0.05) in group 2, respectively. The correlation coefficients between mRR against (mff × AVFRP)1/2 in group 1 and (mff × SPERP)1/2 in group 2 were 0.8 (P < 0.001) and 0.72 (P < 0.05), respectively.
Conclusions: This clinical study did not indicate an inverse relation between the atrial and ventricular rates that had been reported by the previous experimental study. The ventricular rate during AF appeared to be quantitatively related to the atrial rate via AV node function. The importance of the slow pathway in determining the ventricular rate during AF was observed.  相似文献   
104.
Hepatocyte growth factor (HGF) is a most potent factor for mature parenchymal hepatocytes in primary culture and may act as a trigger for liver regeneration. We purified HGF from rat platelets to homogeneity and cloned both human and rat HGF cDNA. HGF is a heterodimer molecule composed of the 69 kDa alpha-subunit and the 34 kDa beta-subunit. HGF has no amino acid sequence homology with other known peptide growth factors and possesses the highest potential among known growth factors to stimulate proliferation of hepatocytes in primary culture. HGF is derived from a single chain precursor of 728 amino acid residues and the precursor is proteolytically processed to form a two-chain mature HGF. The alpha-subunit of HGF contains 4 kringle structures and HGF has a homology (38%) with plasmin. Biologically active recombinant human HGF could be expressed from COS-1 cells and CHO cells transfected with cloned cDNA. HGF activity and the HGF mRNA level are markedly increased in the liver following insult such as hepatitis, by the administration of hepatotoxins, ischaemia, physical damage and partial hepatectomy. Moreover, HGF mRNA is induced in the lung and kidney, in the presence of liver injury. In situ hybridization revealed that HGF-producing cells in liver are non-parenchymal liver cells, presumably Kupffer and sinusoidal endothelial cells. Therefore, HGF from neighbouring cells (Kupffer and sinsuoidal endothelial cells) and distal organs (lung and kidney) may function as a trigger for liver regeneration by both a paracrine mechanism and an endocrine mechanism. HGF has mitogenic activity for renal tubular epithelial cells, epidermal melanocytes and keratinocytes as well as mature hepatocytes, and has the potential to promote cell migration for some epithelial cells, including normal human keratinocytes. Since cell growth and cell motility are relevant to tissue repair and embryogenesis, HGF may well have important roles in tissue repair and embryogenesis as well as in liver regeneration.  相似文献   
105.
Abstract  The active form of vitamin B12 (methylcobalamin) has been reported to be effective on sleep-wake rhythm disorders. Previous studies, however, were performed under open trial, and the effect of vitamin B12 has not been properly evaluated. The aim of this double-blind study was to investigate the efficacy of methylcobalamin on delayed sleep phase syndrome (DSPS). Methylcobalamin (3 mg/day) or placebo was administered for 4 weeks. The subjects were 50 patients with DSPS aged 13–55 years (26.8 ± 1.3), 27 of whom received the active drug while 23 received the placebo. No significant differences were observed between the 2 groups in subjective evaluations of mood or drowsiness during the daytime or in night sleep by sleep-log evaluation. These results indicate that 3 mg methylcobalamin administered over 4 weeks is not an effective treatment for DSPS.  相似文献   
106.
Abstract: Five cases of pancreas divisum, clinically diagnosed by endoscopic retrograde choledochopancreatography (ERCP), were studied histopathologically. They consisted of four biopsied cases and one patient who underwent pancreatoduodenectomy under the diagnosis of a suspected pancreatic carcinoma. Fibrosis was found in three out of the five cases, two cases with fibrosis in the dorsal pancreas and one in the ventral pancreas. In the two dorsal fibrosis pancreas cases, fibrosis was distributed in the intra- and interlobular areas and was accompanied by atrophy or disappearance of the acinar cells. These findings were compatible with chronic obstructive pancreatitis, distal to a stricture of the pancreatic duct. In the one ventral fibrosis pancreas case, i. e., the pancreatoduodenectomized case, fibrosis was distributed mainly in the interlobular area associated with hemosiderin deposition. Hemosiderin deposition was also observed in inflammatory foci at the posterior aspect of the ventral pancreas. Hence, such interlobular fibrosis developed in relation to the inflammatory foci, and was not caused by pancreas divisum. Therefore, in pancreas divisum, abnormal findings were observed in the dorsal pancreas tissue, and they were compatible with chronic obstructive pancreatitis. (Dig Endosc 1994; 6 : 74–79)  相似文献   
107.
Abstract: Endoscopic gastric mucosal resection (EGMR), by which a large specimen can be obtained, has been developed for the diagnosis and treatment of the borderline lesion (B. L.) or early gastric cancer (EGC), since biopsy specimens obtained by conventional techniques are too small to make an accurate diagnosis in number of cases. Thirty-eight lesions in 35 cases (26 lesions in 23 cases with B. L. and 12 lesions in 12 cases with EGC) were resected for the purpose of treatment by EGMR, and 24 lesions (6 submucosal tumors, 3 B. L. s, 14 cases of EGC and 1 malignant lymphoma) for the purpose of diagnosis. By means of histological examination of the bite biopsy specimens following EGMR, twenty-three lesions in 26 cases (89%) with a B. L. and 8 in 12 cases (67%) with EGC for treatment by EGMR were found to have been completely resected. After further histological examination of EGMR specimens obtained for diagnosis, one out of 3 B. L. s was diagnosed as EGC (IIa) and the others as bengin lesions. Out of 14 EGC cases, 6 were diagnosed as carcinoma, 3 as B. L. s and 5 as benign lesions. In Group III lesions obtained by conventional endoscopic biopsy, 8 out of 40 lesions (20%) were defined as EGC, 28 lesions (70%) as a B. L. and 4 lesions (10%) as benign lesions respectively by means of histological examination of the EGMR specimens. Although obvious side effects were observed in 4 cases, these patients could be treated by endoscopic management or drug therapy. It can be concluded that EGMR, by which large specimens can be obtained, is a useful procedure for the purpose of diagnosing and treating gastric mucosal lesions without causing major risk.  相似文献   
108.
109.
BACKGROUND: Up to now, for a successful buttonhole puncture of the vascular access vessel, the fistula should be punctured by the same experienced medical staff for 2-3 months, using sharp needles, until a fixed puncture route is established. METHODS: We developed a timesaving method to create the fixed puncture route for the buttonhole technique. In this method, after the usual haemodialysis (HD), a newly developed thumbtack-shaped polycarbonate peg is thrust toward the access vessel along the same path as the puncture needle that has just been removed. Then, at the beginning of the next HD, the peg is removed and a dull puncture needle is inserted along the track already formed by the peg left in place. These steps are repeated at each HD session for 14 days. Thereafter, the vascular access is achieved at HD sessions by inserting a dull puncture needle through the established puncture route. RESULTS: This buttonhole puncture approach was used in 37 patients for 3 months. While the polycarbonate peg was in place, patients experienced no restrictions in their normal activities of daily living, except during bathing and showering. As for puncture pain, no patient found the pain of the buttonhole technique to be greater than that of the conventional puncture technique. Moreover, no significant bleeding was noted during HD. With this buttonhole puncture approach, only one patient had enough erythema at the puncture site to suggest possible infection. After HD, the time for bleeding to stop was <10 min in 95% of patients. CONCLUSION: This study showed the new timesaving method for creating a buttonhole to be safe and useful.  相似文献   
110.
A 30 year old female was admitted twice during her pregnancy for genital bleeding. An ultrasonography at 19 weeks gestation showed several nodules on the chorionic plate. Cardiotocography during labor at 37 weeks gestation indicated a non-reactive pattern. A 2230 g infant girl was delivered soon after rupture of membranes with asphyxia and hydrops fetalis. The placenta weighed 600 g with a maximal thickness of 6 cm. Nodules occupied about one-third of the placenta and were diagnosed as placental hemangiomas. Postnatal examination revealed that the infant had disseminated intravascular coagulation and cardiac failure. This baby recovered after treatment in the intensive care unit, and was discharged home on the 52nd day of life.  相似文献   
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