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Collagenous colitis is an inflammatory mucosal disorder of the colon with distinctive histopathological features, including a thickened subepithelial collagen layer. The clinical course is usually benign, but serious complications, including death, may occur. In the present report, a 69-year-old woman with watery diarrhea and collagenous colitis developed bloody diarrhea that was refractory to treatment medications, including corticosteroids and azathioprine. Endoscopic and histopathological studies showed a focal neutrophilic inflammatory process that progressed to a diffuse and extensive form of colitis, eventually requiring total proctocolectomy. Careful histological review of the resected colon showed no evidence of persistent collagenous colitis. These findings suggest an important need for continued long-term follow-up of patients with collagenous colitis because superimposed and serious colonic complications may occur, including a severe and extensive pancolitis refractory to medications and necessitating total proctocolectomy.  相似文献   
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BACKGROUND: Although selective serotonin reuptake inhibitors (SSRIs) are the mainstay of pharmacological treatment for obsessive-compulsive disorder (OCD), some OCD patients do not show improvement. Sometimes, the addition of a low-dose atypical antipsychotic, such as risperidone, or olanzapine, to ongoing SSRI treatment has been shown to be effective. However, there are patients who still show no response after trials with this augmentation therapy. In the present study, we examined the clinical features of OCD patients who showed different responses to pharmacological treatment. SUBJECTS AND METHOD: Fifty OCD patients were divided into three groups according to their pharmacological responses: responders to SSRI (group A: n= 25), responders to SSRI with an atypical antipsychotic (group B: n= 15), and non-responders to both SSRI and SSRI with an atypical antipsychotic (group C: n= 10). We examined the clinical features such as age, sex, age of onset, duration of illness, types of obsessive-compulsive symptoms, severity, improvement after treatment, insight into disease, depression, comorbidity, involving family members in compulsive or ritualistic behavior, and the level of social adaptation of each OCD group. RESULTS: Twenty five patients showed a good response to SSRI monotherapy, 15 showed a response to antipsychotic augmentation, and 10 were non-responders to both SSRI and SSRI with an atypical antipsychotic. Significantly lower insight levels were observed only in group B and higher depressive levels in group C. OCD patients who were refractory to SSRI monotherapy showed comorbidity at a significantly higher frequency. OCD patients in group A showed significantly greater improvement, and group B showed inferior social adaptation after treatment. There were no significant differences in age, sex, age of onset, duration of illness, severity, involving family members in compulsive or ritualistic behavior, and social adaptation before treatment in the three OCD groups. CONCLUSION: There were differences in the clinical features of OCD patients who showed different responses to pharmacological treatment. Our results suggest that OCD is clinically and biologically heterogeneous. It may be important to divide OCD patients into subgroups for future studies.  相似文献   
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Data now exist from which an accurate definition for serotonin toxicity (ST), or serotonin syndrome, has been developed; this has also lead to precise, validated decision rules for diagnosis. The spectrum concept formulates ST as a continuum of serotonergic effects, mediated by the degree of elevation of intrasynaptic serotonin. This progresses from side effects through to toxicity; the concept emphasizes that it is a form of poisoning, not an idiosyncratic reaction. Observations of the degree of ST precipitated by overdoses of different classes of drugs can elucidate mechanisms and potency of drug actions. There is now sufficient pharmacological data on some drugs to enable a prediction of which ones will be at risk of precipitating ST, either by themselves or in combinations with other drugs. This indicates that some antidepressant drugs, presently thought to have serotonergic effects in animals, do not exhibit such effects in humans. Mirtazapine is unable to precipitate serotonin toxicity in overdose or to cause serotonin toxicity when mixed with monoamine oxidase inhibitors, and moclobemide is unable to precipitate serotonin toxicity in overdose. Tricyclic antidepressants (other than clomipramine and imipramine) do not precipitate serotonin toxicity and might not elevate serotonin or have a dual action, as has been assumed.  相似文献   
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To evaluate the usefulness of myocardial scintigraphy as a monitoring tool for chronic doxorubicin (DXR) cardiotoxicity, a rat model was used to investigate the relationship between the myocardial uptake of thallium 201 (Tl) or rechnetium 99m pyrophosphate (99mTc-PPi) and histological changes of the heart. Although there was no significant difference in myocardial Tl uptake between control and DXR-treated rats at an early phase after Tl injection, late-phase Tl uptake was significantly higher in the DXR-treated rats than in the control rats, indicating a slow wash-out of Tl from the myocardium. The wash-out rate calculated from scintigraphic examination of DXR-treated rats was significantly decreased with increasing degree of cardiomyopathy. Since the Tl wash-out rate was sharply decreased even in animals with minimal histological changes, it may be a possible monitoring tool for the early detection of chronic DXR cardiotoxicity. On the other hand, myocardial99mTc-PPi images could be obtained only in rats with severe myocardial changes and hence would not useful for early detection.  相似文献   
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The authors experienced a case of Mirizzi’s syndrome successfully treated with endoscopic nasogallbladder drainage (ENGBD). The patient was a 63‐year‐old man. He was admitted with abdominal pain and jaundice. Laboratory data indicated leukocytosis and elevation of serum bilirubin level. Abdominal ultrasound showed marked swelling of gallbladder and debris in the gallbladder, therefore, the authors strongly suspected Mirizzi’s syndrome. He had past history of acute myocardial infarction and treated with anticoagulation therapy. Then, the authors couldn’t perform surgical removal or percutaneous transhepatic drainage, and tried endoscopic transpapillary drainage. Endoscopic retrograde cholangiopancreatography revealed smooth stricture in the superior portion of common bile duct and occlusion of the cystic duct, and ENGBD was then performed. After ENGBD, his complaints, laboratory data, swelling of gallbladder and stricture of common bile duct were all remarkably improved.  相似文献   
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