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排序方式: 共有6843条查询结果,搜索用时 15 毫秒
21.
The utility of MRI using magnetization transfer (MT) enhanced pulse sequences to diagnose hepatic cirrhosis in a rat model was investigated. Hepatic T1 was measured with and without MT off-resonance RF pulses in 17 treated and six control rats. The livers were evaluated histologically, and the hydroxyproline content quantitatively measured. We did not find a statistically significant linear correlation between the MR relaxation times and the degree of tissue injury. However, the MR measurements performed with MT were superior to those without differentiating the treated and control groups. Specifically, the T1 times were 695 ±76 ms for the treated group, versus 748 ± 61 ms in the controls; P= 0.095. The T1sat times were also lower in the treated group, with statistical significance: 367 ± 51 ms versus 421 ± 38 ms, P = 0.016. Finally, the change in the relaxation rates (the inverse of the relaxation times) with and without saturation were 1.31 ± 0.22 s?1 (treated group) versus 1.05 ± 0.12 s?1 (controls), which differed significantly, P= 0.001. 相似文献
22.
Katsumi Kimura Naotaka Fujita Yutaka Noda Go Kobayashi Kei Ito Jun Horaguchi Toshiki Sugawara Osamu Takasawa 《Digestive endoscopy》2004,16(1):54-57
Clinical diagnosis of chronic cholecystitis is made based on diffuse hyperechoic thickening of the gallbladder wall as shown by ultrasonographic examination. We herein report three cases of chronic cholecystitis showing localized hypoechoic thickening of the gallbladder wall that mimicked gallbladder cancer by ultrasonography. Histologically, hypertrophy of the muscularis propria was a common characteristic finding in these three patients. A smooth surface of the inner hypoechoic layer of the thickened wall was considered to be a reliable finding in the differential diagnosis between this type of chronic cholecystitis and gallbladder cancer. 相似文献
23.
Satoko Kobori Fumihito Yoshii Hirohide Takahashi Shigeharu Takagi Kei Funakoshi 《Clinical neurology》2007,47(1):53-55
We report a patient who developed overlapping symptoms of ophthalmoplegia and oropharyngeal palsy after Campylobacter jejuni infection. A 15-year-old man had diarrhea and fever, and developed dysarthria, diplopia and ptosis two weeks later. He did not show ataxia, weakness or abnormal tendon reflexes in the extremities during the clinical course. In the acute phase of the disease, we found significant elevation of anti-GQlb and anti-GTla IgG antibodies in the serum, and high-dose intravenous immunoglobulin therapy remarkably ameliorated the symptoms. Our patient was atypical of Fisher syndrome or pharyngeal-cervical-brachial (PCB) weakness, and this is the first case of multiple cranial neuropathy associated with C. jejuni infection. 相似文献
24.
Chinori Kurata MD PhD Sakae Shouda MD Tadashi Mikami MD Yasushi Wakabayashi MD Tomoyasu Nakano MD Tsuyoshi Sugiyama MD Kei Tawarahara MD PhD Kazuyuki Sakata MD PhD 《Journal of nuclear cardiology》1997,4(6):515
Background. [123I]Metaiodobenzylguanidine (MIBG) imaging has been used to assess cardiac sympathetic nerve abnormalities. We evaluated the clinical significance of myocardial MIBG imaging as a measure of cardiac sympathetic nervous system function by comparing it to heart rate variability and plasma norepinephrine level.Methods and Results. In 211 subjects, we analyzed heart rate variability with 24-hour electrocardiography, performed scintigraphy with MIBG, and measured plasma norepinephrine levels. Time and frequency domain measures of heart rate variability were calculated with the Marquette heart rate variability program (Marquette Electronics, Milwaukee, Wis.). Early and late myocardial MIBG uptakes were measured at 15 and 150 minutes after injection, respectively. MIBG clearance rate from the heart and heart-to-lung and heart-to-mediastinum ratios of MIBG activities were calculated. On the whole, heart rate variability, including low-frequency power, correlated positively, but modestly so, with late MIBG uptake and negatively with MIBG clearance rate. The plasma norepinephrine level correlated negatively with late MIBG uptake and with heart rate variability, including low-frequency power, and positively with MIBG clearance rate. Similar correlations were also observed in patient subgroups with coronary artery disease, diabetes mellitus, and renal failure, but these correlations were weak (R2 < 0.5).Conclusions. Increased cardiac sympathetic nervous system activity may be associated with increased myocardial MIBG clearance and decreased heart rate variability, including low-frequency power. Because these associations were not strong, however, the combination of heart rate variability with MIBG may allow an interactive assessment of the cardiac autonomic nervous system. 相似文献
25.
Naoki Hori Hakuo Takahashi‡ Takeshi Okanoue Yoshihiko Sawa Takashi Mori Shiro Takami Manabu Yoshimura† Kei Kashima 《Clinical and experimental pharmacology & physiology》1995,22(8):506-511
1. Endothelium-derived nitric oxide (NO) is a potent vasodilator. Because the body oxidizes it to nitrate ions, NO3-, measurement of the serum concentration and the urinary excretion of NO3- may be an index for endogenous NO. We investigated the role of NO on hyperdynamic circulation in cirrhotic and partial portal vein-ligated rats by measuring NO3. 2. Liver cirrhosis was induced by administration of thioacetamide. Systemic and splanchnic haemodynamics and splenic-systemic shunting were determined by tracer microspheres. The concentration of NO3- was measured by using high-performance liquid chromatography with an anion-column. 3. We found that systemic and splanchnic hyperdynamic circulation existed to almost the same extent in cirrhotic and in portal vein-ligated rats as compared to the controls and sham-operated rats, respectively. Splenic-systemic shunting was markedly greater in portal vein-ligated rats than in cirrhotic rats. 4. Serum NO3- levels and urinary excretion of NO3- in cirrhotic rats tended to increase as compared to the controls. On the other hand, the levels in portal vein-ligated rats were significantly increased as compared to those of the sham-operated rats, and were significantly and negatively correlated to the splanchnic arterial resistance and total vascular resistance. The amount of urinary excretion of NO3- significantly correlated to splenic-systemic shunting (r = 0.61, P<0.05) only in portal vein-ligated rats. 5. We suggest that these high levels of NO3- in portal vein-ligated rats relate to the extensive formation of porto-collateral vasculature or acute changes in systemic and splanchnic haemodynamics due to portal vein-ligation. 相似文献
26.
It is well known that lung cancer develops frequently in patients with idiopathic interstitial pneumonia (IIP) (9.8-22.8%). We investigated 4 patients who developed lung cancer among the 28 patients with IIP (14.3%) who were admitted to our hospital from June 1981 to March 1989. Many reports have pointed out the clinical features of lung cancer associated with IIP as male sex, old age, heavy smoking, and poor prognosis. Our 4 series were agreed with these clinical features. Lung cancer associated with IIP have been often reported to occur in the lower and peripheral regions of the lung, and honeycomb structures are frequently seen. But we found that lung cancer in IIP could actually occur in both the lower and upper regions of the lung and does not occur only in the honeycomb structures. There was no obvious dominance of any histological type among the tumors. If lung cancer is suspected in a patient with IIP, tumor markers are of some value for diagnosis, but are not sensitive enough to be used alone. 相似文献
27.
28.
Ngai Suk Wai; Tang Oi Shan; Lao Terence; Ho Pak Chung; Ma Ho Kei 《Human reproduction (Oxford, England)》1995,10(5):1220-1222
Intravaginal misoprostol has been shown to be effective forcervical priming before a surgically induced abortion. The objectivewas to investigate the effectiveness of oral misoprostol incervical dilatation prior to vacuum aspiration between the 6thand 12th weeks of pregnancy. The results showed that in nulliparouspatients, the median cervical dilatation in the treatment group(7.8 mm) was significantly greater than that in the placebogroup (3.7 mm). In multiparous patients, the difference wasalso statistically significant (9.8 versus 6.0 mm). The easeof dilatation, assessed subjectively by the operating surgeons,was significantly improved in the treatment group. There wasalso a significant reduction in the duration of the operationand in the mean blood loss in the treatment group. The side-effectsencountered in the treatment group were mild and well acceptedby the women. Oral misoprostol is an effective and safe methodfor cervical dilatation prior to vacuum aspiration in firsttrimester pregnancy. 相似文献
29.
A promoter variant of the ATP-binding cassette transporter A1 gene alters the HDL cholesterol level in the general Japanese population 总被引:3,自引:0,他引:3
Shioji K Nishioka J Naraba H Kokubo Y Mannami T Inamoto N Kamide K Takiuchi S Yoshii M Miwa Y Kawano Y Miyata T Miyazaki S Goto Y Nonogi H Tago N Iwai N 《Journal of human genetics》2004,49(3):141-147
To investigate the effects of polymorphisms in the ATP-binding cassette transporter A1 (ABCA1) gene on the high-density lipoprotein cholesterol (HDL-C) level and the incidence of myocardial infarction (MI), we performed association studies. Sequence analysis identified 14 polymorphisms in the promoter region of ABCA1. After considering linkage disequilibrium, three polymorphisms in the promoter region and 11 polymorphisms from the JSNP database were determined in 1,880 subjects recruited from the Suita Study, representing the general population in Japan. We evaluated the association between the ABCA1 genotype and HDL-C level adjusted not only for standard factors, but also for genetic factors including ApoA1 and ApoE genotypes. Of the 14 polymorphisms tested, the G(–273)C (P=0.0074), C(–297)T (P=0.0195), and IMS-JST071749
(P=0.0093) polymorphisms were significantly associated with the HDL-C level in the Suita population. We could reconfirm that the G(–273)C genotype was influential in another set of subjects (P=0.0310, n=743). However, the distribution of the ABCA1 G(–273)C
genotype in subjects with MI (n=598) was not different from that in the control population (n=801). These results indicate that ABCA1 G(–273)C
has a significant effect on the HDL-C level in the general Japanese population, but not on the incidence of MI. 相似文献
30.
Tetsushi Furukawa Tei-ichi Yamane Tomoko Terai Yoshifumi Katayama Masayasu Hiraoka 《Pflügers Archiv : European journal of physiology》1996,431(4):504-512
The role of the cytoskeleton in the rundown and reactivation of adenosine triphosphate (ATP) sensitive K+ channels (KATP channels) was examined by perturbing selectively the intracellular surface of inside-out membrane patches excised from guinea-pig ventricular myocytes. Actin filament-depolymerizing agents (cytochalasins and desoxyribonuclease I) accelerated channel rundown, while actin filament stabilizer (phalloidin) or phosphatidylinositol biphosphate (PIP2; inhibitor of F-actin-severing proteins) inhibited spontaneous and/or Ca2+-induced rundown. When rundown was induced by cytochalasin D or by long exposure to high Ca2+, channel activity could not be restored by exposure to MgATP, but application of F-actin with MgATP could reinstitute channel activity. The processes of rundown and reactivation of cardiac KATP channels may thus be influenced by the assembly and disassembly of the actin cytoskeletal network, which provides a novel regulatory mechanism of this channel. 相似文献