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81.
The p53 gene has been implicated as a tumor suppressor gene involved in the pathogenesis of lung cancer. Our previous study revealed that the p53 gene is frequently mutated with a distinct nucleotide substitution pattern in small cell lung cancer specimens in Japanese patients. In this study, we examined 30 primary, resected non-small cell lung cancer samples in Japanese patients using complementary DNA-polymerase chain reaction and sequencing. Mutations changing the p53 coding sequence were found in 14 of 30 tumor samples (47%), while G:C to T:A transversions which are uncommon in other cancers such as colon cancer were the most frequently observed mutations, in agreement with an earlier report on non-small cell lung cancer in American patients. Furthermore, the present study shows for the first time that in univariate and multivariate analyses, the presence of p53 mutations is closely associated with lifetime cigarette consumption.  相似文献   
82.
Thymidylate synthetase (TS) and thymidine kinase (TK) are know to catalyze the methylation of dUMP for the de novo synthesis of dTMP and the phosphorylation of thymidine for the salvage synthesis of dTMP in the pyrimidine pathway, respectively, and both enzyme activities are high in rapidly proliferating tissues. In the present study, these enzyme activities and the immunohistochemistry using monoclonal anti-bromodeoxyuridine (BrdU) were investigated during the period of proliferation of bone marrow cells after the hypoplastic period induced by cyclophosphamide (Cy) treatment in rats. Right after Cy treatment, nucleated cell count (NCC) of bone marrow cells, BrdU labelling ratio and TK activity were abruptly decreased. On the other hand, TS activity peaked at day 5 followed by an increase of TK activity, NCC and BrdU labelling ratio from day 7 after Cy treatment. These results indicate that, in the proliferation of bone marrow cells, the DNA de novo synthesis rises at first, and secondly, the DNA salvage synthesis predominantly increases with the increase of bone marrow cells labelled with BrdU, i.e., increase of the cells in the S phase.  相似文献   
83.
Squamous cell carcinoma of the thyroid--a report of three cases   总被引:1,自引:0,他引:1  
Three cases of squamous cell carcinoma of the thyroid are reported herein. In all cases, the carcinoma occurred in old age and was characterized by a rapidly growing tumor, usually associated with dyspnea and dysphagia. The prognosis of all 3 cases was poor, with a mean survival of only 6.3 months. Although squamous metaplasia is an accepted etiology of this disease, clinical investigation of the cases presented here does not favor it in consideration of the clinical features of papillary carcinoma of the thyroid with squamous metaplasia. The histological findings of our cases revealed areas of cystic formation, suggesting that some of these carcinomas may be derived from remnants of embryonic origin.  相似文献   
84.
A case-control study to evaluate the efficacy of lung cancer screening conducted by us showed that lung cancer screening may reduce the mortality of the disease up to 28%. Assuming this efficacy is unbiased, and that the screening rate is 51.6%, which was observed in the control group in the above study, the number of lung cancer deaths prevented by screening in the study period was calculated to be 47 for males and females combined. In the same study population, screen-detected lung cancer patients (N = 207) in the same study period were followed and the 7-year survival rate (46.9%) was compared to the 5-year survival rate (11.3%) obtained by the Osaka Cancer Registry, in which screen-detected lung cancer patients were only 1.8%. The number of lung cancer deaths prevented by screening, estimated by the difference in the above two survival rates, was 74 (95% confidence interval; 55–93). The number of lung cancer deaths prevented by screening estimated from the case-control study was significantly lower than that estimated from the survival analysis. This indicates that the efficacy of lung cancer screening estimated by the case-control study was within the range that could be explained by the actual long-term survivors among the screen-detected patients in the study population.  相似文献   
85.
MRI of ossification of ligamentum flavum.   总被引:11,自引:0,他引:11  
Magnetic resonance imaging of 28 patients with radiological and/or histopathologically proved ossification of the ligamentum flavum (OLF) was reviewed. The locations of OLF were cervical (n = 4), thoracic (n = 22), and lumbar (n = 2). On T1- and T2-weighted images, OLF demonstrated low signal intensity. Areas of high or intermediate signal intensity within the OLF on T1-weighted images were observed in three cases and were interpreted to be due to fat infiltration. In six cases, high intensity areas in the spinal cord caused by compressing OLF were demonstrated on T2-weighted images. Gadolinium-diethylenetriamine pentaacetic acid, which was used in four cases, showed cord enhancement at the level of compression by OLF in three cases.  相似文献   
86.
Y Matsuki  K Suzuki  M Hara  A Kitani  T Hirose  M Harigai  M Kawakami  N Tanaka  M Kawagoe  H Nakamura 《Ryūmachi》1992,32(2):154-9; discussion 159-62
Arterial thrombosis is one of the major symptoms of antiphospholipid syndrome (APS). However, thrombosis in a primary branch of the aorta has rarely been reported in APS. We report here a case of APS complicated by thromboses in both the left subclavian artery and the left external iliac vein. A 32-year-old woman was admitted in May, 1990 complaining of no pulse in the left superficial arteries (e.g., left radial artery) for the past 5 years and acute swelling of the left lower extremity. A left ascending phlebography showed an occlusion of the external iliac vein and arteriography revealed obstruction in the left subclavian artery. Collateral circulations were developed at the site of each thrombus. Clotting and immunological studies revealed a prolonged APTT, a high titer of anticardiolipin antibody and lupus anticoagulant positive. We ruled out various diseases and clinical risk factors predisposing to both arterial and venous thromboses. Accordingly, we concluded that both thromboses were based on APS. Following treatment with anticoagulants, aspirin and corticosteroid, the swelling of her left thigh was diminished and the antibody titer was decreased within 3 months.  相似文献   
87.
Summary Effects of STA-MCA anastomosis on two patients with neovascular glaucoma due to occlusion of the internal carotid artery are presented. Both patients improved in visual acuity and central retinal artery pressure as well as in signs of transient ischaemic attack. Postoperative angiography showed a marked decrease in collateral flow through the ophthalmic artery, which is reversed from the normal direction, with the development of blood flow through the anastomosis. Discussion is offered indicating that the lack of collateral flow through both the anterior and posterior communicating arteries is important in addition to occlusion of the internal carotid artery in order to produce full-blown ischaemic oculopathy such as venous stasis retinopathy, neovascular glaucoma or rubeosis iridis. It is stressed that EC-IC bypass surgery should be performed soon after the appearance of ischaemia and before the development of neovascular glaucoma or rubeosis iridis in order to obtain normal vision. In ischaemic oculopathy the results of EC-IC bypass can be evaluated objectively and quantitatively by many noninvasive neuro-ophthalmological tests which are important in discussing the efficacy of the bypass surgery.  相似文献   
88.
The effect of chemical deafferentation, vagotomy(VGX), and gangliosympathectomy (GSX) on the density offibers containing calcitonin gene-related peptide (CGRP)and substance P (Sub.P) in the rat gastric wall was studied. Chemical deafferentation bycapsaicin abolished the density of CGRP-immunoreactive(IR) fibers, not Sub.P-IR fibers. Ten days after VGX,the density of CGRP-IR or Sub.P-IR fibers in the mucosa was largely reduced, while no reductionof CGRP-IR and Sub.P-IR fibers was seen in submucosaland muscular layers. GSX significantly reduced thedensity of CGRP-IR fibers in the mucosa and caused a moderate decrease in the fibers in submucosaland muscular layers. Pretreatment with6-hydroxydopamine, a neurotoxin for noradrenergicnerves, did not affect the density of CGRP-IR fibers inthe gastric wall. The density of Sub.P-IR fibers in thegastric wall was not affected by GSX. These studiesindicate that the CGRP-IR and Sub.P-IR fibers in themucosa are susceptible to extrinsic nerve denervation compared with those in the submucosa and musclelayers, that a major portion of the CGRP-IR fibers inthe mucosa is of both vagal and spinal origin, and thata major portion of the Sub.P-IR fibers in the mucosa is of vagal origin. Furthermore, thepresent results support that CGRP-IR fibers, notSub.P-IR fibers, in the rat stomach arecapsaicin-sensitive.  相似文献   
89.
BACKGROUND & AIMS: Nutrients and properties of lipases affect survival of lipolytic activity during aboral gastrointestinal transit. Whether different doses and formulations of bacterial lipase and diets affect steatorrhea was tested in pancreatic-insufficient dogs. METHODS: A dose of 0-600,000 IU of powdered and 135,000 and 300,000 IU of liquid bacterial lipase was given with a standard meal to 5 dogs with ligated pancreatic ducts. In 4 dogs, 0 or 300,000 IU (normal 6-hour postprandial amount) of powder bacterial lipase was also given with five meals containing 850 kcal with different nutrient caloric densities (mixture design). Coefficients of fat absorption during 72- hour fecal balance studies were used to assess treatments. RESULTS: With the standard meal, powder bacterial lipase reduced steatorrhea in a dose-dependent manner (P = 0.03), and 135,000 and 300,000 IU of the liquid form decreased steatorrhea more than powder bacterial lipase (P = 0.017 and 0.057, respectively). Coefficients of fat absorption with 300,000 IU of powder bacterial lipase correlated (r2 = 0.79; P < 0.001) with increasing proportions of fat calories in diets. CONCLUSIONS: Liquid bacterial lipase decreases steatorrhea more than powder, and 300,000 IU of powder bacterial lipase ingested with high-fat meals corrects canine pancreatic steatorrhea. The combination of adequate mixing of small amounts (milligrams) of bacterial lipase and high-fat meals abolishes canine steatorrhea and may abolish human pancreatic steatorrhea. (Gastroenterology 1997 Jun;112(6):2048-55)  相似文献   
90.
The effect of ketamine infusion to control the intractable pain which had not responded to ordinary procedures in 12 patients with advanced cancer were evaluated. Ketamine 250 mg or 500 mg in 500 ml of transfusion fluid with or without 10 to 20 mg of droperidol was administered intravenously at the rate of 3 to 20mg of ketamine per hour. The pain scores by VAS in most of the patients decreased significantly with an averaged value of 8.3 before the treatment to 1 during the procedure. The durations of this therapy lasted from over 6 hours to 48 days. Slight disorientation in one patient and drowsiness in 5 were seen during the infusion. No cardiovascular or respiratory complications were noted. These results indicate that ketamine infusion is a useful therapeutic procedure to treat cancer pain which resist ordinary pain therapies.  相似文献   
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