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1.
The direct causal relationship between dermatomyositis-polymyositis (PM) and malignancy remains controversial. We describe herein the case of a patient who underwent surgical treatment for colon cancer, which had preceded the onset of PM with tumor relapse. The PM markedly improved following the initiation of steroid therapy, and has remained under control, probably as a result of chemotherapy. The current concepts of variable clinical courses and the possible mechanism for the association of PM with malignancy are discussed following this case report.  相似文献   
2.
The neuroleptic malignant syndrome (NMS) is a life-threatening complication of neuroleptic treatment. To elucidate the pathogenesis of NMS, an animal model has been developed. Experimental rabbits treated with haloperidol (1 mg/kg) by intramuscular injection, were studied for the diagnostic symptoms of increased muscle rigidity, elevated body temperature, and high serum creatine phosphokinase (CPK) level. Administration of haloperidol (1 mg/kg) and atropine (0.4 mg/kg), and exposure to high ambient temperature (35°C) induced a significant increase in electromyographic activity with muscle rigidity similar to that observed in patients with NMS. Such rabbits also showed elevated body temperature and serum CPK value. In addition to the similarity of the signs and symptoms, all parameters measured (muscle rigidity, body temperature, and serum CPK level) were normalized by dantrolene treatment. The effectiveness of dantrolene in the experimental animal partially confirms the validity of this animal model for NMS. This experimental animal model for NMS may be useful to elucidate the pathogenesis of NMS.  相似文献   
3.
The structure-acute toxicity relationship of aromatic hydrocarbons was examined in mice. In all test compounds, the acute toxicity was determined under 2 conditions: control LD50 (LD50-cont) and carbon tetrachloride (CCl4)-pretreated LD50 (LD50-CCl4). The CCl4-pretreatment was done in order to evaluate the toxic potency of compound itself without the influence of metabolism. Both log (1/LD50-cont) and log (1/LD50-CCl4) were functions of the log P, n-octanol/water partition coefficient, i.e., log (1/LD50-cont) = 0.080 log P − 1.532 and log (1/LD50-CCl4) = −0.040(log P)2 + 0.157 log P − 1.373. Both equations were statistically significant (P < 0.01). The ratio of LD50-cont/LD50-CCl4 indicated that metabolic activation is more evident in hydrophobic compounds than in hydrophilic compounds. The results suggest that hydrophobicity of the aromatic hydrocarbons plays an important role in determining their acute toxicity.  相似文献   
4.
Primary extranodal malignant lymphoma frequently occurs in the gastrointestinal tract; however, it is rarely encountered in the rectum. We report herein the case of an 85-year-old man who underwent abdominoperineal resection for primary malignant lymphoma of the rectum, and 1 year later, developed hematemesis caused by gastric metastasis. To our knowledge this is the first case report of such distant metastasis developing from malignant lymphoma of the rectum.  相似文献   
5.
We assessed the effects of chronic treatment with haloperidol (0.5-2 mg/kg/day, p.o., 17 days) and methamphetamine (1-2 mg/kg/day, p.o., 17 days; 4 mg/kg/day, p.o. 9 days) on hippocampal kindled seizures using a kindling procedure with low-frequency (about 3 Hz) electrical stimulation in cats. The number of stimulating pulses required to trigger epileptic afterdischarge (pulse-number threshold, PNT) was considered an indicator of seizure threshold. Haloperidol, 0.5 and 1.0 mg/kg, reduced the duration of epileptic afterdischarge (afterdischarge duration, ADD) without affecting PNT, and 2.0 mg/kg strongly reduced PNT and ADD. Methamphetamine, 2.0 mg/kg, reduced PNT and ADD, and 4.0 mg/kg preferentially reduced PNT. The effects of the two drugs on hippocampal kindled seizures were found to be partially opposite to those on amygdala kindled seizures, suggesting the different response of these limbic structures to dopamine receptor manipulation.  相似文献   
6.
We have investigated the effect of the immunomodulator ubenimex (hereafter referred to as bestatin) on the enzymatic degradation of the extracellular matrix by human renal cell carcinoma SN12M cells during the invasive process. The invasion of SN12M cells into reconstituted basement membrane (Matrigel) was inhibited by the presence of bestatin in a concentration-dependent manner. However, bestatin did not have any effect on tumor cell adhesion and migration to the extracellular matrices which may be involved in tumor cell invasion. Bestatin inhibited the degradation of type IV collagen by tumor cells, but not by tumor-conditioned medium (TCM), in a concentration-dependent manner. We also found that bestatin inhibited hydrolysing activities towards substrates of aminopeptidases in SN12M cells. Since bestatin was found to inhibit aminopeptidase activity, the inhibition of tumor invasion by bestatin is likely to be associated with its action as an enzyme inhibitor. Bestatin only slightly inhibited tumor cell plasmin activity, which can lead to the conversion of the latent collagenase to the active form, but this slight effect was not significant. The zymography of TCM from SN12M cells showed that the treatment of tumor cells with bestatin resulted in the disappearance of the 68 kDa type IV collagenase-enzyme level (active form) and slight reduction of the 72 kDa type IV collagenase-enzyme level (latent form). These results indicated that bestatin may inhibit tumor cell invasion through a mechanism involving its inhibitory action on aminopeptidases in tumor cells, suggesting that the aminopeptidase may partly be associated with the conversion of a latent form of type IV procollagenase to an active form or the secretion of the collagenases from tumor cells.  相似文献   
7.
An acute intraperitoneal injection of phencyclidine (PCP) caused a tetrodotoxin-reversible increase in extracellular release of 3,4-dihydroxyphenylacetic acid (DOPAC) and homovanillic acid (HVA) in the dialysates from the medial frontal cortex of the rat. Moreover, there was an increase in the tissue content of DOPAC and HVA with acceleration of dopamine (DA), but not noradrenaline, utilization in the cortical area after systemic administration of PCP. These results suggest that PCP facilitates DA metabolism in the medial frontal cortex by increasing impulse flow in the DA neurons projecting to the prefrontal region.  相似文献   
8.
Abstract A 13-year-old girl with a history of Kawasaki disease underwent coronary artery bypass grafting because of angina pectoris due to a giant coronary artery aneurysm on the left main trunk artery. Nine years after the operation, the patient had an uneventful pregnancy followed by a normal vaginal delivery. This is the first case of a successful pregnancy after coronary artery bypass grafting for Kawasaki coronary artery disease.  相似文献   
9.
Tanii H  Higashi T  Oka R  Saijoh K 《Brain research》2000,868(1):141-146
Allylnitrile and crotononitrile induce behavioral abnormalities in mice. To explore the possible involvement of the vestibular system in these behavioral abnormalities, the expression of Fos protein, used as an indicator of neuronal activity, was examined within various brain structures in allylnitrile-, crotononitrile- and vehicle-treated mice. In each nitrile-treated mouse, Fos expression was observed in brain structures, which were divided into two groups. The structures in group 1 showed Fos expression between 1.5 h and 2 days postdosings, and in those in group 2 expression remained for up to 30 days postdosing. As most of these structures, especially in group 2, were identical to some Fos-positive structures observed after unilabyrinthectomy, the present results indicate that each nitrile induces Fos expression by causing a change in the peripheral vestibular system, resulting in behavioral abnormalities.  相似文献   
10.
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