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971.
K Koizumi G Uchiyama T Araki T Hihara H Ogata S Monzawa K Kachi M Matsusako 《Kaku igaku. The Japanese journal of nuclear medicine》1989,26(3):361-368
Ga-67 scintigrams in patients with malignant diseases sometimes reveal uptake of the tracer in the bone metastases. Detectability of Ga-67 scintigraphy for metastatic bone tumors and benign bone lesions was compared with that of Tc-99m bone scintigraphy. Countable bone metastases detected by bone scintigraphy were evaluated whether the lesion showed apparent, faint, or negative Ga-67 uptake. Of 47 lesions 23 (49%) showed apparent uptake and 17 (36%) showed negative uptake. On the other hand, of 71 benign bone lesions, only 7 (10%), mostly fracture/osteotomy, showed apparent uptake of the tracer. Uptake in the other benign lesions such as trauma of the ribs, spondylosis deformans, and arthrosis deformans was rather faint. In patients with multiple bone metastases, 9 patients (82%) out of 11 showed more prominent abnormal findings in Tc-99m MDP bone scintigraphy than in Ga-67 scintigraphy; that is, Ga-67 scintigraphy was not able to reveal all metastatic bone lesions. In patients with untreated or recurrent tumors, relation between Ga-67 uptake in the tumors and that in the bone metastases was evaluated. Of 7 patients with negative Ga-67 uptake in the primary tumors, 5 showed positive Ga-67 uptake in the bone metastases; that is, there seemed to be little relation between Ga-67 affinity to the primary tumors and that to the bone metastases. Mechanisms of the Ga-67 uptake in the bone metastases were discussed. Not only the tumor cells or tissues in the bone metastases but also bone mineral or osteoclasts might be the deposition sites of Ga-67. 相似文献
972.
Hiromi Ishibashi Minoru Nakamura Atsumasa Komori Kiyoshi Migita Shinji Shimoda 《Seminars in immunopathology》2009,31(3):399-409
The liver is an organ consisting of the largest reticulo-endothelial cell network in the body and playing an important role
in host defense against invading microorganisms. The organ is comprised of parenchymal cells and many different types of non-parenchymal
cells, all of which play a significant role. Even biliary epithelial cells are not only the target in autoimmune liver diseases
but also have central role in orchestrating several immune cells involved in both innate and acquired immunity. Tissue damage
caused by various agents results in inflammation, necrosis, fibrosis, and, eventually, distortion of normal hepatic architecture,
cirrhosis, and functional deterioration. 相似文献
973.
Although the pathophysiology of acute pancreatitis appears to be greatly influenced by the production of ascites, little is known about the mechanism. To investigate the effects of pancreatitis-associated ascitic fluid (PAAF) on macrophage function, we examined the effects of PAAF obtained from a rat model of severe acute pancreatitis on the ability of peritoneal macrophages to produce tumor necrosis factor-alpha (TNF-alpha). In addition, we compared the responses of PAAF-treated and PAAF-untreated macrophages to lipopolysaccharide (LPS) by evaluating their TNF-alpha production and nuclear factor-kappaB (NFkappaB) activation. Incubation of peritoneal macrophages with the PAAF led to the rapid and prolonged activation of NF-kappaB and to TNF-alpha production. Pyrrolidine dithiocarbamate, a potent inhibitor of NF-kappaB activation, attenuated the macrophage TNF-alpha production by PAAF. Macrophages produced TNF-alpha in response to LPS, but the cytokine production was significantly reduced when macrophages were pretreated with PAAF. The suppression of TNF-alpha production by PAAF pretreatment accompanied the impairment of NF-kappaB activation in response to LPS. These results indicate that the PAAF of severe acute pancreatitis may play important roles in the pathologic course of this disease through its effects on macrophage function. 相似文献
974.
975.
Kiyoshi Hoshina M.D. Yasuko Yoshida M.D. Misuzu Kambara M.D. Kazuko Tsukada M.D. 《Pediatrics international》1986,28(2):222-225
Reserve capacity of Lh and FSH secretion was examined by standarized LHRH loading rest in 30 endocrinologically normal children, whose age ranged from 3 to 13 years. These sunjects were divided by sex. Both male and female subjects were divided into three groups by their chronological age, that is, Group A: under 6 years, Group B: 7 to 10 years and Group C: over 11 years of age. In the male the peakl values of LH were 10.86 ± 1.9 (mean ± SD) for Group a, 23,3 ± 7.3 for Group B, and 73.13 ± 6.4 mIU/ml for Group C. Corresponding values in the female were 8.58 ± 1.3, 20.56 ± 3, and 60.38 ± 8.5 mIU/ml, respectively. These intergroup differences in the peak LH values weer statistically significant (p<0.01)in both sexes. Regarding peak FSH values, no difference was seen among groups of either male or female cases. These findings indicate that even in prepuberty the reserve capacity of LH secretion begins to increase around the age of about 7 years. 相似文献
976.
Kenichi Sakamoto Takeshi Saito Rena Orman Kiyomi Koizumi †Jason Lazar †Louis Salciccioli ‡Mark Stewart 《Epilepsia》2008,49(6):982-996
Purpose: Autonomic consequences of seizures are common, but can be severe. We sought to define changes in autonomic activity from limbic cortical seizures and their impact on the heart.
Methods: We studied kainic acid (KA)-induced seizures in urethane-anesthetized rats using peripheral nerve, blood pressure (BP), and ECG recordings and echocardiography.
Results: Seizures were associated with massive increases in parasympathetic (vagus nerves) and sympathetic (cervical sympathetic ganglion >renal nerve >splanchnic nerve) activity. Seizure-associated activity increases were greater than activity changes induced by nitroprusside or phenylephrine (each producing BP changes of >50 mmHg). Increases in c-fos expression were found in both sympathetic and parasympathetic medullary regions (as well as hypothalamic areas). Baroreceptor reflex function (tested with nitroprusside and phenylephrine) was impaired during seizures. Finally, a significant fraction of the animals died and the mechanism of death was defined through ECG, BP, and echocardiographic measures to be profound cardiac dilatation and bradyarrhythmia leading to hypoperfusion of the brain and ultimately hypoperfusion of the heart. Cardiovascular changes occur within seconds (or less) of autonomic nerve activity changes and death by these mechanisms takes minutes.
Discussion: We propose that the massive parasympathetic and sympathetic outflow that occurs during a seizure gets compounded by respiratory distress (driving both autonomic nervous system divisions in the same direction) causing mechanical dysfunction, slowing the heart, and hypoperfusing the brain. 相似文献
Methods: We studied kainic acid (KA)-induced seizures in urethane-anesthetized rats using peripheral nerve, blood pressure (BP), and ECG recordings and echocardiography.
Results: Seizures were associated with massive increases in parasympathetic (vagus nerves) and sympathetic (cervical sympathetic ganglion >renal nerve >splanchnic nerve) activity. Seizure-associated activity increases were greater than activity changes induced by nitroprusside or phenylephrine (each producing BP changes of >50 mmHg). Increases in c-fos expression were found in both sympathetic and parasympathetic medullary regions (as well as hypothalamic areas). Baroreceptor reflex function (tested with nitroprusside and phenylephrine) was impaired during seizures. Finally, a significant fraction of the animals died and the mechanism of death was defined through ECG, BP, and echocardiographic measures to be profound cardiac dilatation and bradyarrhythmia leading to hypoperfusion of the brain and ultimately hypoperfusion of the heart. Cardiovascular changes occur within seconds (or less) of autonomic nerve activity changes and death by these mechanisms takes minutes.
Discussion: We propose that the massive parasympathetic and sympathetic outflow that occurs during a seizure gets compounded by respiratory distress (driving both autonomic nervous system divisions in the same direction) causing mechanical dysfunction, slowing the heart, and hypoperfusing the brain. 相似文献
977.
T. Suzuki J. Koizumi H. Shiraishi N. Ishikawa K. Ofuku M. Sasaki T. Hori N. Ohkoshi I. Anno 《Neuroradiology》1990,32(1):74-76
Summary A case of mitochondrial encephalomyopathy (MELAS) with mental disorder is reported. The SPECT study using123I-iodoamphetamine (IMP) and MRI study revealed abnormality in the left parieto-occipital areas without abnormality in the brain CT or brain scintigram. These findings suggest a localized dysfunction of the brain capillary endothelium in association with the cerebral involvement of mitochondrial encephalomyopathy. 相似文献
978.
Abstract: Plasma 25-hydroxyvitamin D (25-OH D), 1,25-dihydroxy vitamin D (1,25-(OH)2 D) and parathyroid hormone (PTH) concentrations were determined in 30 outpatients receiving various antiepileptic drugs (AED). None of the patients exhibited high plasma PTH levels. The plasma 1,25-(OH) 2 D levels were normal or high, a'though in a third of the patients the 25-OH D levels were reduced. There was a corre'ation between the 25-OH D and serum calcium levels. These findings suggest that the low plasma concentrations of 25-OH D, not 1,25-(OH)2 D, might play an important part in the occurrence of AED-induced disturbances of bone metabolism. 相似文献
979.
The concentrations of Cd, Zn, Cu, and metallothionein (MT) in the liver, renal cortex, and renal medulla were determined in 24 male and 15 female younger thoroughbreds (age 27 to 97 months) and two old male horses (age 154 months and 190 months). High correlations were found between Zn and MT in the liver (partial correlation coefficient 0.836), between Cd and MT in the renal cortex (partial correlation coefficient 0.786), and between Cd and Zn in the renal cortex (partial correlation coefficient 0.675), while the correlation between Cd and MT in the liver was low (partial correlation coefficient 0.124). In the renal medulla, high correlations were found between Cd and Zn (partial correlation coefficient -0.631), between Zn and Cu (partial correlation coefficient 0.881), and between Cd and Cu (partial correlation coefficient 0.785). Therefore, in the liver, the MT concentration is the most highly correlated with the Zn concentration and is not correlated with the CD concentration unless artificially exposed to Cd. In the renal cortex, the MT and Cd concentrations are very highly correlated with each other. The Zn concentration is about 20 micrograms/g when the Cd concentration in the renal cortex is the lowest. 相似文献
980.
Influences of dietary restriction and age on liver enzyme activities and lipid peroxidation in mice 总被引:11,自引:0,他引:11
Dietary restriction extends maximum life span in rodents by unknown mechanisms. We compared livers from 12- and 24-mo-old mice fed control (C, approximately 95 kcal/wk) or restricted (R, approximately 55 kcal/wk) amounts of diet since 3 wk of age. We hypothesized that dietary restriction might alter the activity levels of enzymes with possible relevance to aging processes. The enzymes included several xenobiotic metabolizers, radical scavengers (catalase, superoxide dismutase, glutathione peroxidase), superoxide sources (xanthine oxidase, peroxisomal beta-oxidation of palmitoyl-CoA) and glucose-6-phosphatase. Lipid peroxidation (LP) was also measured. Comparing 12- and 24-mo-old mice, the strongest diet or age effect was an increased catalase activity for group R (42% higher at 12 mo, 64% at 24 mo). LP was clearly lower in group R at 12 mo (a 30% decrease) and somewhat lower (13%) at 24 mo than in group C. Similarly, in 12-mo-old C and R mice injected with either the P-450 inducer beta-naphthoflavone (beta-NF in corn oil) or with corn oil alone. R mice showed higher catalase activity (40-44%) and lower LP (43-46%) in both beta-NF-injected and vehicle-injected groups. These data suggest that if free radical damage is involved in aging, it may be a particular kind of damage, that is, that in part prevented by a selective increase in catalase activity. 相似文献