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91.
Ultrasonography was performed in 661 dialysis patients and acquired cystic disease of the kidney was found in 156 (125 men and 31 women). A higher incidence of cystic disease was found in males. There was no significant difference between the patients with and those without acquired cystic disease in terms of average age, but the duration of haemodialysis in those with acquired cystic disease was significantly longer. There was an increased incidence of cystic disease in patients with glomerulonephritis and the duration of haemodialysis in these patients was significantly longer. This suggests that the increased incidence of acquired cystic disease of the kidneys in the patients with glomerulonephritis is simply related to the longer duration of treatment. Twelve patients with renal carcinoma were found in this study. The average age at diagnosis of renal carcinoma was not significantly different between the patients with and those without acquired cystic disease, but the duration of dialysis was significantly longer in renal carcinoma patients with acquired cystic disease. The incidence of renal carcinoma in dialysis patients with acquired cystic disease was 3.85% and in those without it was 1.19%. These rates are considerably higher than those found in the general population and indicate that the risk of renal carcinoma is higher in dialysis patients both with and without acquired cystic disease.  相似文献   
92.
1. The effects of protamine on the rabbit isolated small mesenteric artery were investigated both in the presence and in the absence of heparin, by the isometric tension-recording method. 2. The dissociation constant for the binding of heparin to protamine has never been previously reported, so in order to minimize the effects of protamine, known to have a vasodilator action, and to examine only the effects of a heparin-protamine complex, the experiments with heparin were performed in the presence of high concentrations of heparin (21-700 u ml-1), concentrations at which heparin itself does not affect the vascular tone. 3. Protamine (15-500 micrograms ml-1), in the absence of heparin, was found to inhibit (P < 0.05) noradrenaline (1 microM)-induced contractions both in endothelium-intact and in endothelium-denuded tissues. 4. Such vasodilator action of protamine in either endothelium-intact or -denuded tissues continued, even in the presence of excess heparin at a heparin/protamine (H/P) ratio of 1.4 u micrograms -1, but was almost completely blocked in the presence of a much greater excess of heparin (H/P ratio > or = 4.7 u micrograms -1): heparin was present both before and during the application of protamine. 5. The vasodilator action of protamine in the absence of heparin was prolonged both in the endothelium-intact and -denuded tissues after protamine had been washed out from the bath with Krebs solution.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
93.
A 34-year-old woman was admitted with an abnormal shadow on a chest X-ray film. Under a preoperative diagnosis of benign bronchogenic cyst, operation was carried out and the tumor was found to be originating from the right main vagal nerve in the mid-superior mediastinum. The vagal nerve was transected to remove the tumor. Pathological diagnosis was a neurinoma. Postoperative complication was chylothorax which was successfully treated with thoracic drainage and intravenous hyperalimentation.  相似文献   
94.
Aneurysms of the inferior left ventricular wall represent only a small fraction of all aneurysms that have been reported in surgical series. And in comparison to anterior left ventricular aneurysms, a comparatively higher percentage of reported inferior wall aneurysms was classified as false. A 73-year-old male was admitted for acute inferior myocardial infarction. Three weeks after admission, cardiac catheterization was carried out. Coronary arteriography revealed triple vessel disease and left ventriculography showed an aneurysm of the inferior left ventricular wall, whose feature near the mitral annulus was multiple fenestrations. Left ventricular aneurysmectomy and aortocoronary bypass grafting to the left anterior descending artery were simultaneously performed under cardiopulmonary bypass with moderate hypothermia. The pathological feature was a true aneurysm. The postoperative course was uneventful.  相似文献   
95.
The matrix metalloproteinase matrilysin (MMP-7) is a member of the matrix metallo-proteinase gene family, which is believed to play an important role in tumor invasion and metastasis. We have previously found that matrilysin mRNA is specifically expressed in colorectal cancers and adenomas and that its message is localized in the tumor cells themselves. We examined the effects of activated Ki-ras oncogene on the expression of matrilysin in colon cancer cells. We showed that both mRNA and the enzymatic activity of matrilysin were induced by the introduction of activated Ki-ras into SW1417 colon cancer cells. To understand the mechanisms regulating this induction, we analyzed alterations of AP-1 activity induced by activated Ki-ras, using the chloramphenicol acetyltransferase assay. AP-1 activity in SW1417 cells expressing activated Ki-ras was higher than that in control cells. The gel-shift assay also showed higher levels of AP-1 binding protein in SW1417 cells expressing activated Ki-ras than those in control cells. Our results suggest that activated Ki-ras may play a role in inducing expression of matrilysin through an AP-1-dependent pathway in colon cancer cells.  相似文献   
96.
97.
BACKGROUND CONTEXT: Although posterior lumbar interbody fusion (PLIF) for degenerative lumbar diseases is routine, there are few reports on double-level PLIF. PURPOSE: To evaluate the clinical outcomes of double-level PLIF. STUDY DESIGN/SETTING: A retrospective study of operated cases in Gifu, Japan. PATIENT SAMPLE: Nineteen patients (8 men and 11 women, 59.5+/-10.2 years) who underwent double-level PLIF between 1996 and 2001. OUTCOME MEASURES: Operation time, blood loss, complications, the Japanese Orthopaedic Association (JOA) score for back pain and lumbar sagittal alignment were evaluated. METHODS: Patients were examined retrospectively at follow-ups of 3.6+/-1.7 years. Primary diseases were spondylolisthesis, spinal canal stenosis, degenerative scoliosis and herniated intervertebral disc. Fusion areas were L3 to L5 in 15 cases and L4 to S1 in 4 cases. RESULTS: The mean JOA score increased from an initial score of 12.9+/-3.5 to 21.3+/-4.9 at the final follow-up. There was a positive correlation (R=0.718, p<.001) between the increase in lordotic angle and the increase in the JOA score. Several parameters suggested that the surgical invasiveness was not minimal. CONCLUSION: Double-level PLIF provided satisfactory results and preserved lumbar spine lordosis.  相似文献   
98.
A 52‐year‐old Japanese woman who presented with gastrointestinal (GI) bleeding underwent a proximal gastrectomy for a gastrointestinal stromal tumor (GIST) with a foveolar hyperplasia at the apex of the tumor, 4.5 cm in size, located in the upper body of the stomach. Although GIST are often asymptomatic and are found only incidentally, clinical symptoms such as bleeding, abdominal pain, or obstruction, occasionally lead to a premorbid diagnosis. When submucosal tumors present GI bleeding, the source of the bleeding usually is an ulceration of the mucosa over the tumor. However, in the present study, it was thought that the bleeding originated from the region of foveolar hyperplasia.  相似文献   
99.
OBJECTIVES: Graft failure has been reported when the arterial conduit, such as the internal thoracic artery (ITA) or the right gastroepiploic artery (GEA), is grafted to a lower grade coronary artery stenosis. The shear stress as a significant factor affecting graft patency was compared between the arterial conduit and the saphenous vein graft (SVG) after surgery. METHODS: In 101 patients, 40 ITAs, 27 GEAs and 34 SVGs were examined using a Doppler-tipped guide wire during postoperative angiography. The graft flow volume and shear stress were calculated from velocity and diameter data. The study grafts were classified according to the grade of native coronary artery stenosis: group L had more than 50 up to 75% stenosis, and group H had more than 75% stenosis. Group H consisted of 25 ITAs, 17 GEAs and 21 SVGs, while group L consisted of 15 ITAs, 10 GEAs and 13 SVGs. RESULTS: In group H, graft flow volume did not significantly differ among the ITA (34+/-11 ml/min), GEA (36+/-16 ml/min) and SVG (41+/-15 ml/min), and graft shear stress significantly (ITA vs. GEA P<0.0001; GEA vs. SVG P<0.01) differed among the ITA (16.0+/-4.8dyn/cm(2)), GEA (9.1+/-3.2dyn/cm(2)) and SVG (4.8+/-1.6dyn/cm(2)). In group L, flow volume was lower (P<0.001) in the ITA (18+/-6 ml/min) and GEA (13+/-8 ml/min) than in the SVG (35+/-16 ml/min), and shear stress was significantly (P<0.001) greater in the ITA (13.7+/-4.9dyn/cm(2)) than the GEA (5.6+/-2.0dyn/cm(2)) or SVG (4.6+/-2.0dyn/cm(2)). CONCLUSIONS: These data suggest that shear stress of the ITA is superior and maintained despite the flow volume being reduced by flow competition. Lower shear stress of the GEA for intermediate stenosis may be associated with the development of conduit failure.  相似文献   
100.
High-performance liquid chromatography has been used to quantitate benzalkonium chloride (alkylbenzyldimethylammonium chloride) in complex ophthalmic formulations at or below concentration levels of 50 ppm. The method involves a one-step dilution for sample preparation and direct injection; therefore, recovery and/or conversion problems are nonexistent. The assay is quick, specific, reproducible, and simple. This new approach makes routine determinations far simpler than previous methods and is especially useful for product stability studies and quality control procedures.  相似文献   
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