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31.
Abdominal hysterectomy after treatment of cervical cancer by radiation therapy is associated with a significant rate of postoperative vesicovaginal fistulas. In this series, five patients with invasive cancer of the cervix treated by radiation therapy developed new cervical or uterine neoplasms 1 to 27 years after treatment. All underwent abdominal hysterectomy without postoperative fistula formation. Success is attributed to cautious surgical technique and to the use of the omental pedicle graft to bring new vascularity to the vaginal apex and bladder base. The technique of forming an omental pedicle graft is described. 相似文献
32.
Sakai K Oyama Y Okada Y Akaike N Nakata M Chikahisa L 《Environmental toxicology and pharmacology》2001,10(3):95-101
Tri-n-butyltin (TBT), one of environmental pollutants accumulated in mollusks, at nanomolar concentrations decreases cellular content of glutathione (GSH), suggesting that TBT increases cell vulnerability to oxidative stress because GSH has a role in catabolizing hydrogen peroxide (H(2)O(2)). In order to examine this possibility, the effect of tri-n-butyltin chloride (TBTCl) on rat thymocytes suffering from oxidative stress induced by H(2)O(2) was examined using a flow cytometer with four fluorescent probes; ethidium bromide, 2',7'-dichlorofluorescin diacetate, 5-chloromethylfluorescein diacetate and annexin-V-FITC. TBTCl at concentrations ranging from 100 nM to 1 μM attenuated H(2)O(2)-induced decrease in cell viability in a dose-dependent manner. It was unlikely that TBTCl reduced H(2)O(2)-induced oxidative stress because TBTCl failed to affect H(2)O(2)-induced oxidation of intracellular molecule (2',7'-dichlorofluorescin) and H(2)O(2)-induced decrease in cellular content of GSH. Results suggest that TBTCl may inhibit the pathway of cell death induced by H(2)O(2) or that TBTCl may induce a protective substance against the oxidative stress produced by H(2)O(2). 相似文献
33.
Phosphodiesterase III inhibitor attenuates rat sinusoidal obstruction syndrome through inhibition of platelet aggregation in Disse's space 下载免费PDF全文
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36.
Shinji Uchida Naotsugu Obayashi Hiroshi Yamanari Katashi Matsubara Daiji Saito Shoichi Haraoka 《Heart and vessels》1992,7(3):164-167
Summary We report a case of a papillary fibroelastoma originating from the left ventricular endocardium in the outflow tract which was discovered by echocardiography in an asymptomatic patient. Two echocardiographic features were observed: (1) the tumor surface was smooth, and characteristic papillary formation was not detected; and (2) the outline of the mass was clearly defined as a dense echo, with the central, radiolucent, portion surrounded by a highly refractive linear echo at the level of the maximum diameter of the mass. The excised tumor was covered with a gelatinous substance that masked multiple papillae on the surface, but its echolucent center could not be explained by the pathology of the tumor which was solid centrally. Our case indicates that a papillary fibroelastoma may sometimes show echocardiographic findings similar to those of a myxoma, although other investigators have not noted the smooth surface and the echolucent center makes it indistinguishable from a myxoma. Thus, in some cases, it is difficult to distinguish papillary fibroelastoma from myxoma by echocardiography. 相似文献
37.
Severe exacerbation of hepatitis after short-term corticosteroid therapy in a patients with "latent" chronic hepatitis B 总被引:2,自引:0,他引:2
Shiota G Harada K Oyama K Udagawa A Nomi T Tanaka K Tsutsumi A Noguchi N Kishimoto Y Horie Y Suou T Kawasaki H 《Liver》2000,20(5):415-420
We present a case of severe exacerbation of hepatitis after short-term corticosteroid therapy for chronic inflammatory demyelinating polyneuropathy (CIPD) with "latent" chronic hepatitis B showing no HBV-related antigens and antibodies. After corticosteroid pulse therapy for CIPD, the patient had severe exacerbation of hepatitis twice. Although she did not show any hepatitis B virus (HBV)-related antigens or antibodies, sequences of HBV were detected in serum and liver by a nested polymerase chain reaction. A sequence analysis of HBV at the second exacerbation showed that the G-to-A point mutation at nucleotide 1896 that converted codon 28 from tryptophan (TGG) to a stop codon (TAG) in the precore region resulted in amino acid change, which has been frequently observed in fulminant hepatitis and severe hepatitis in Japan. 相似文献
38.
Toshihiko Iwamoto Yi Feng Kazushi Shinozaki Shun-ichi Koyama Tetsuo Oyama Masaru Takasaki 《Geriatrics & Gerontology International》2003,3(2):93-100
Background: The relationship between lipoprotein(a) (Lp(a)) and ischemic stroke is still controversial in the elderly. The purpose of the present paper was to evaluate the significance of Lp(a) in the development of extracranial carotid lesions and ischemic stroke.
Methods: A total of 371 elderly subjects, studied with carotid ultrasonography (US) and brain computed tomography (CT), was stratified into two groups according to serum Lp(a) levels: the normal Lp(a) and high Lp(a) (>40 mg/dL) groups. Carotid plaques were divided into three types based on the US echogenicity: hypoechoic, hyperechoic, and heterogeneous plaques. Low-density areas (LDA) on brain CT images were classified into three groups depending on their distribution: basal ganglionic, cortical and only leuko-araiosis types.
Results: The incidence of bilateral carotid lesions and the ratios of hypoechoic and heterogeneous plaques were significantly higher in the high Lp(a) group than in the normal Lp(a) group. Both the mean height and length of plaque were also greater in the high Lp(a) group. Mean Lp(a) levels were significantly elevated in cases with hypoechoic and heterogeneous types, compared to the cases without lesions. Higher mean Lp(a) levels were seen in cases with any kind of LDA than in normal subjects on CT, but there was no significant difference in the incidence of each LDA between the two groups.
Conclusions These findings indicate that serum Lp(a) is strongly related to carotid lesions, especially hypoechoic and heterogeneous plaque types, in Japanese elderly patients. This suggests that Lp(a) could promote the formation of lipid-rich atheromatous plaque with intraplaque hemorrhage or superimposed thrombi. Serum Lp(a) also seemed to be a risk for all types of LDA. 相似文献
Methods: A total of 371 elderly subjects, studied with carotid ultrasonography (US) and brain computed tomography (CT), was stratified into two groups according to serum Lp(a) levels: the normal Lp(a) and high Lp(a) (>40 mg/dL) groups. Carotid plaques were divided into three types based on the US echogenicity: hypoechoic, hyperechoic, and heterogeneous plaques. Low-density areas (LDA) on brain CT images were classified into three groups depending on their distribution: basal ganglionic, cortical and only leuko-araiosis types.
Results: The incidence of bilateral carotid lesions and the ratios of hypoechoic and heterogeneous plaques were significantly higher in the high Lp(a) group than in the normal Lp(a) group. Both the mean height and length of plaque were also greater in the high Lp(a) group. Mean Lp(a) levels were significantly elevated in cases with hypoechoic and heterogeneous types, compared to the cases without lesions. Higher mean Lp(a) levels were seen in cases with any kind of LDA than in normal subjects on CT, but there was no significant difference in the incidence of each LDA between the two groups.
Conclusions These findings indicate that serum Lp(a) is strongly related to carotid lesions, especially hypoechoic and heterogeneous plaque types, in Japanese elderly patients. This suggests that Lp(a) could promote the formation of lipid-rich atheromatous plaque with intraplaque hemorrhage or superimposed thrombi. Serum Lp(a) also seemed to be a risk for all types of LDA. 相似文献
39.
S Kitamura C Oyama K Kawachi Y Miyagi R Morita Y Yamada K Kim T Nishii Y Kawashima 《Japanese circulation journal》1984,48(7):705-712
Pre- and postoperative hemodynamics were assessed in 14 consecutive patients who developed ventricular septal perforation (VSP) following acute myocardial infarction (AMI). Results were correlated with the surgical outcome and with postoperative clinical improvements. The patients were divided into 3 groups according to the time intervals between the onset of AMI and the operation; acute (within 2 weeks after AMI), subacute (between 2 and 4 weeks) and chronic (after 4 weeks). In the above groups, 6, 2 and 6 patients were included, respectively. Eleven patients had anteroseptal infarction and 3 patients sustained inferior infarction. The survival rates were 33, 50 and 100% in the acute, subacute and chronic groups, respectively with an overall survival rate of 64%. Hemodynamic comparisons between survivors and non-survivors revealed that the systolic aortic pressure and left ventricular stroke volume index were significantly higher and the right ventricular end-diastolic pressure was significantly lower in survivors than in non-survivors (p less than 0.05). Although no statistical significance was obtained, left ventricular end-diastolic volumes and ejection fractions were higher in survivors. No difference was present between survivors and non-survivors in either Qp/Qs, Pp/Ps, Rp/Rs, systolic pulmonary pressure, left ventricular end-diastolic pressure or cardiac index. Patients with low arterial pressure and high right ventricular end-diastolic pressure under intensive medical regimens, indicating the presence of cardiogenic shock and/or associated right ventricular infarction or severe failure, had a high mortality and should be considered for emergency operation. Postoperative hemodynamics improved significantly in all variables measured (p less than 0.05-0.01). Patients with a VSP should all be considered for surgery unless a definite contraindication exists. 相似文献
40.
Carter RM Hofstotter C Tsuchiya N Koch C 《Proceedings of the National Academy of Sciences of the United States of America》2003,100(3):1399-1404
Previous studies of associative learning implicate higher-level cognitive processes in some forms of classical conditioning. An ongoing debate is concerned with the extent to which attention and awareness are necessary for trace but not delay eye-blink conditioning [Clark, R. E. & Squire, L. R. (1998) Science 280, 77-81; Lovibond, P. F. & Shanks, D. (2002) J. Exp. Psychol. Anim. Behav. Processes 28, 38-42]. In trace conditioning, a short interval is interposed between the termination of the conditioned stimulus (CS) and the onset of the unconditioned stimulus (US). In delay conditioning, the CS and US overlap. We here investigate the extent to which human classical fear conditioning depends on working memory. Subjects had to carry out an n-back task, requiring tracking an item 1 or 2 back in a sequentially presented list of numbers, while simultaneously being tested for their ability to associate auditory cues with shocks under a variety of conditions (single-cue versus differential; delay versus trace; no task versus 0-, 1-, and 2-back). Differential delay conditioning proved to be more resilient than differential trace conditioning but does show a reduction due to task interference similar in slope to that found in trace conditioning. Explicit knowledge of the stimulus contingency facilitates but does not guarantee trace conditioning. Only the single-cue delay protocol shows conditioning during the more difficult working memory task. Our findings suggest that the larger the cognitive demands on the system, the less likely conditioning occurs. A postexperimental questionnaire showed a positive correlation between conditioning and awareness for differential trace conditioning extinction. 相似文献