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51.
To determine the clinical significance of regional left ventricular asynergy in patients with impending myocardial infarction, we recorded two-dimensional echocardiograms (2DE) serially and performed coronary angiography immediately after the hospital admission in nine patients with initial impending infarction and their last anginal attacks were within 48 hours. Left ventricular asynergy on the first 2DE was observed in six of nine patients during symptom-free periods (Group A: LV asynergy group). Five of the six patients had significant coronary artery lesions (greater than or equal to 75% stenosis) in at least one major coronary artery. Intracoronary filling defects were detected in four of the five patients. Another three patients without asynergy (Group B) had significant fixed stenosis. Coronary artery spasm was observed in two patients during coronary angiography, but no patient had intracoronary filling defects. Intracoronary nitroglycerin (0.1-0.3 mg) reduced the severity of coronary artery narrowing in two patients. In addition, urokinase (240,000-480,000 IU) via the corresponding vessel (PTCR) in the remaining seven patients resulted in reduction in the severity of coronary artery stenosis in four patients, but not in the remaining three patients. Left ventricular wall movement in the asynergy group improved rapidly and no asynergy was observed by the seventh hospital day in five of the six patients. Successful PTCR treatment resulted in improvement of left ventricular wall movement. No asynergy was found in the non-asynergy group throughout their hospitalizations. These findings indicated that abnormal left ventricular wall movement is found in patients with impending myocardial infarction, even during symptom-free periods, but the wall movement gradually improves. The 2DE observations are useful for estimating the clinical status and for planning precise therapy for impending myocardial infarction.  相似文献   
52.
T Hijikata  H Saito  T Yohro 《The Prostate》1986,8(3):277-291
Gross anatomy and the light and electron microscopic characteristics of the musk shrew (Suncus murinus, Insectivora) prostate are described. The prostate is a pair of compound tubuloalveolar glands with one main excretory duct for each gland. Each gland is divided into ventral and dorsal lobes. The tubuloalveoli are larger in diameter and the secretory cells are lower in the ventral than in the dorsal lobes. Probable spontaneous release of secretory granules and accumulation of secretory material in secretory lumina are only observed in the ventral lobes. Secretory material is often crystallized in the secretory lumina. The epithelium of excretory ducts consists of mucous-type secretory cells and the boundary between this epithelium and the glandular epithelium is complex. The glandular epithelium consists of secretory and clear cells. This report illustrates that the structure of the prostate of musk shrew is unique among mammals.  相似文献   
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Endothelin, a 21-amino acid peptide produced by vascular endothelial cells, caused a sustained constriction of isolated large cerebral arteries of cats in a dose-dependent manner. The increased tone of the tissue did not return to the resting level after repeated washings. No vasodilator response was evoked by endothelin in the presence of an active tone. The contractile response of cerebral arteries was not inhibited by rubbing of the endothelium, cold storage denervation or indomethacin. In contrast, nicardipine or diltiazem antagonized the endothelin-induced contraction non-competitively. No contraction was evoked by endothelin in a Ca2+-free solution while the addition of Ca2+ ions in the presence of endothelin in a Ca2+-free solution caused a sustained contraction. Ca2+-induced contraction in the Ca2+-free solution containing endothelin was also inhibited by nicardipine. Therefore, endothelin causes a direct contraction of the smooth muscles of cat cerebral arteries, probably by activating the influx of Ca2+ ions through L-type Ca2+ channels of smooth muscles.  相似文献   
56.
It is well known that long-term infection with Clonorchis sinensis often causes bile duct cancer, usually. It occurs in the intrahepatic bile duct. We encountered a rare case of clonorchiasis complicated with duodenal papillary cancer. The patient was a woman from China. Although clonorchiasis is rarely found in Japan, the promotion of international exchange may increase the number of visitors from endemic areas. Thus we must pay sufficient attention to this disease. Also, we reported that the microplate ELISA technique was useful in the diagnosis of clonorchiasis with high accuracy in this case.  相似文献   
57.
Cholesteryl ester transfer protein (CETP) greatly affects the metabolism of all lipoprotein classes including low-density lipoprotein (LDL) and high-density lipoprotein (HDL), both known to constitute powerful risk factors for coronary artery disease (CAD). We now report the successful first cloning and characterization of single-chain antibody fragments specific for CETP. A recombinant phage display library was generated using spleen mRNA isolated from BALB/c mice that had been immunized with highly purified CETP. Screening of the library yielded two single-chain antibody fragments with high affinity for CETP, termed 1CL8 and 1CL10, displaying respective KD values of 4.36 x 10(-9) M and 4.64 x 10(-9) M as determined by affinity sensor technology. Amino acid sequence comparison indicated the complementarity-determining regions of the respective heavy chains to be responsible for CETP high affinity binding. Fragment 1CL8 was successfully employed in clinical chemical quantification systems that uncovered an association in humans between plasma CETP concentration and total body fat mass (r=0.50, p<0.002). Because of the demonstrated superb CETP capturing capacity, combined with high binding affinity to CETP, ready access and unlimited supply, 1CL8 and 1CL10 are expected to prove powerful tools for studies on the role of CETP in atherogenesis.  相似文献   
58.
Endoscopic submucosal dissection (ESD) for colorectal cancer is not widely accepted because of its technical difficulty and the risk of perforation. In addition, the risk of peritonitis cannot be completely eliminated even if a perforation is closed successfully. Reported here are two cases of early colon cancer in which the patients sustained iatrogenic perforations of the ascending colon during conventional endoscopic mucosal resection and of the sigmoid colon during ESD, respectively, requiring abdominal decompression with an 18 G Medicut needle. Both of these perforations were successfully treated by endoscopic clipping. In conclusion, conservative medical management may be possible in patients who have undergone successful closure of colonic perforations using endoscopic clipping. In order to perform immediate endoscopic closure, abdominal decompression has been useful to decrease patient discomfort and colonic lumen collapse. Now, CO2 insufflation is being used effectively for the prevention of pneumoperitoneum.  相似文献   
59.
Endoscopic submucosal dissection (ESD) for colorectal tumors is steadily being developed. Safety and standardization of ESD for colorectal tumors have not been yet established because of the technical difficulties and the unsuitable anatomical characteristics of the colon and rectum. The authors mainly use a Flex knife for mucosal incision and a Hook knife for submucosal dissection to perform ESD safely. Skillful colonoscopic control, selection of scope, distal attachment tip hood, adequate high‐frequency generator and correct approach strategy should all be considered for safe performance of ESD. However, the incidence of indicative lesions is rare because the majority of colorectal tumors are adenomatous large laterally spreading tumors, which can be cured by intentional endoscopic piecemeal resection. At present, ESD for colorectal tumors should be performed only at central facilities that have expert colonoscopists. With the development of new devices and associated techniques, technical standardization of ESD for colorectal tumors is expected in the near future.  相似文献   
60.
BACKGROUND: An association between Brugada syndrome and neurally mediated syncope has been described. Although mutations in SCN5A have been identified in Brugada syndrome, the genetic link between Brugada syndrome and neurally mediated syncope has not been determined. OBJECTIVES: The purpose of the study was to clinically and genetically characterize a man with recurrent syncope that originally was diagnosed as neurally mediated syncope at age 8 years but subsequently manifested as Brugada syndrome at age 17 years. METHODS: The proband underwent clinical examination, which included head-up tilt test, sodium channel provocation test, and electrophysiologic study. Genetic screening of SCN5A was performed for the proband and his family members. The biophysical properties of a mutant SCN5A channel in a heterologous expression system were studied using whole-cell, patch clamp technique. RESULTS: The proband showed positive head-up tilt test, coved-type ST elevation recorded from the third intercostal space, and positive pilsicainide provocation test. Ventricular fibrillation was inducible at programmed electrical stimulation, consistent with characteristics of both Brugada syndrome and neurally mediated syncope. A novel nonsense SCN5A mutation (Q55X) was identified in the proband, his mother, and his asymptomatic brother. The heterologously expressed mutant channel was nonfunctional. CONCLUSION: We genetically determined an SCN5A mutation in a patient showing the combined phenotype of neurally mediated syncope and Brugada syndrome. Neurally mediated syncope and Brugada syndrome may share, at least in part, a common pathophysiologic mechanism.  相似文献   
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