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Abstract

Extracts and fractions from the aerial parts of herbal materials of Saussurea involucrata. Kar et Kir ex Maxim (Compositae) were investigated for their whitening activity against mouse-derived immortalized melanocyte cell line. The extract of wild herbs (FS2) possessed a better inhibition (28.2% growth) against melanin cells than that (46.7%) of cultivated herbs (FS1). The whole extracts and middle-polar partitioning fraction show the inhibitory effects, whereas the water-soluble parts show a poor activity in the same assay.  相似文献   
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Activated T cells express inhibitory receptors such as CTLA-4 that can downregulate immune responses. Blockade of or genetic deficiency in CTLA-4 can result in autoimmunity. Therefore, strategies to increase the inhibitory function of CTLA-4 may be attractive in settings of undesirable T cell responses such as autoimmunity or transplant rejection. We have tested the hypothesis that transgenic constitutive expression of CTLA-4 can further attenuate immune responses when compared with normal inducible expression. Our results indicate that transgenic expression of CTLA-4 in mouse T cells (CTLA-4-Tg T cells) results in reduced cell cycle progression and increased apoptosis of TCR-stimulated T cells. CTLA-4-Tg T cells display reduced T cell proliferation in an in vivo model of graft versus host disease (GVHD). These results further our understanding of how CTLA-4 can be manipulated to inhibit immune responses and may help development of new therapeutic strategies for clinical settings of autoimmunity and transplantation.  相似文献   
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Introduction This study aimed to examine the prevalence rates of both post-traumatic stress disorder (PTSD) and major depression at 12 months in workers experiencing different types of occupational injury in Taiwan. Demographic and injury-related risk factors for psychological symptoms were also evaluated. Methods Our study candidates were injured workers in Taiwan who were hospitalized for 3 days or longer and received hospitalization benefits from the Labor Insurance program. A two-staged survey study was conducted. A self-reported questionnaire including the Brief Symptom Rating Scale and Post-traumatic Symptom Checklist was sent to workers at 12 months after injury. Those who met the criteria were recruited for the second-stage phone interview with a psychiatrist using the Mini-international Neuropsychiatric Interview (MINI). Results A total of 1,233 workers completed the questionnaire (response rate 28.0 %). Among them, 167 (13.5 %) fulfilled the criteria for the MINI interview and were invited. A total of 106 (63.5 %) completed the phone interview. The estimated rate of either PTSD/PPTSD or major depression was 5.2 %. The risk factors for psychological symptoms were female gender, lower education level, loss of consciousness after occupational injury, injury affecting physical appearance, occupational injury experience before this event, life experience before and after this injury, length of hospital stay, self-rated injury severity, and percentage of income to the family. Conclusions These results showed that occupational injury can cause long-term psychological impact in workers. Key demographic and injury characteristics may enhance the identification of at-risk occupational injured workers who would benefit from targeted screening and early intervention efforts.  相似文献   
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Glossopharyngeal neuralgia is a relatively rare condition characterized by severe, paroxysmal episodes of lancinating pain in the tongue, throat, ear, and tonsil. This disorder is assumed to be due to compression of the glossopharyngeal nerve by vascular structures. A 47-year-old woman complaining of sharp and lancinating pain in the right periauricular and submandibular areas visited our hospital. Swallowing, chewing, and lying on her right side triggered the pain. Her neurologic examination revealed no specific abnormalities. The results of routine hematologic and blood chemistry studies were all within normal limits. Carbamazepine and gabapentin were given, but her symptoms persisted. Her pain was temporarily relieved only by narcotic pain medication. MRI showed an arachnoid cyst located in the right cerebellomedullary cistern extending to the cerebellopontine cistern. Cyst removal was performed via a right retrosigmoid approach. Lateral suboccipital craniotomy was performed using the right park-bench position. After opening the dura and cerebellopontine angle, the arachnoid cyst was exposed. The arachnoid cyst was compressing the flattened lower cranial nerves at the right jugular fossa. Her symptoms resolved postoperatively. Two months after the operation, she was completely free from her previous symptoms.  相似文献   
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In this report, we introduce a case of thickening of the involved left ventricular apical segment on echocardiography and deep T‐wave inversions in precordial leads on electrocardiography transiently seen in the course of recovery from biventricular takotsubo cardiomyopathy, mimicking apical hypertrophic cardiomyopathy. This result suggests that the echocardiographic finding of transient myocardial edema can be identified by cardiac magnetic resonance imaging in takotsubo cardiomyopathy. Additionally, it persisted a few weeks after full functional recovery. We believe that this case will contribute in part toward clarifying the pathophysiology of takotsubo cardiomyopathy.  相似文献   
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