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1.
Malignant thymomas are among the least common mediastinal tumors in the pediatric age group. Thymomas are considered malignant on the basis of macroscopic and microscopic invasiveness. As only 20 well-documented cases involving children have been reported in the literature, the pattern of responsiveness to therapy and the value of prognostic signs is obscure. Two cases of malignant pediatric thymomas are reported with pathognomonic histoimmunological features of aggressive thymoma. One was cured, with a follow-up of 70 months, and one died while on therapy. Analysis of the histological features and the immunoperoxidase staining displays the complexity of pediatric thymomas and the inability to prognosticate the outcome, respectively.  相似文献   
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Twenty-two patients aged 36–63 years were diagnosed as having Fahr's syndrome on the basis of the presence on CT of unexpected extensive calcification of the basal ganglia. Even when associated with calcification of other brain areas, the main diagnostic criterion remained basal ganglia calcification larger than 800 mm2. Normal values of parathormone, serum calcium and phosphorus excluded hypercalcaemia and hypoparathyroidism. Mitochondrial CNS disease was excluded clinically. MRI and repeated CT and neurological examination were performed in all of the patients. The patients were divided into two groups: neurologically asymptomatic (group 1) and neurologically symptomatic (group 2). T2-weighted sequences demonstrated hyperintense areas in all of the patients involving the white and the grey matter of the brain. In group 1 the hyperintense lesions were significantly smaller than in group 2. The neurological symptoms correlated better with the hyperintensities on T2-weighted MR images than with the calcification demonstrated on CT. Hyperintensities in T2-weighted MRI and the areas shown by CT to have calcification had different locations. In 15 patients with dementia, the white matter of the entire centrum semiovale was bilaterally hyperintense. In another 3 patients with hemiparesis, hyperintense areas in the internal capsule, contralateral to the side of hemiparesis, were demonstrated in the T2-weighted sequence. The hyperintense T2 signals may reflect a slowly progressive, metabolic or inflammatory process in the brain which subsequently calcifies and are probably responsible for the neurological deficit observed.  相似文献   
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Mutations in the MYOC gene may lead to juvenile open-angle glaucoma with high intraocular pressure, and are detected in about 4% of people with adult onset glaucoma. Most of these mutations are found in the third exon of the gene encoding the olfactomedin-like domain located at the C terminus of the protein. Another olfactomedin-related protein, known as noelin or pancortin, is involved in the generation of neural crest cells. Here we describe the identification of a novel olfactomedin-related gene, named optimedin, located on chromosome 1p21 in humans. Optimedin and noelin are both expressed in brain and retina. However, unlike noelin, rat optimedin is also highly expressed in the epithelial cells of the iris and the ciliary body in close proximity to the sites of Myoc expression. In the human eye, optimedin is expressed in the retina and the trabecular meshwork. Both optimedin and myocilin are localized in Golgi and are secreted proteins. The presence of mutant myocilin interferes with secretion of optimedin in transfected cells. Optimedin and myocilin interact with each other in vitro as judged by the GST pulldown, co-immunoprecipitation and far-western binding assays. The C-terminal olfactomedin domains are essential for interaction between optimedin and myocilin, while the N-terminal domains of both proteins are involved in the formation of protein homodimers. We suggest that optimedin may be a candidate gene for disorders involving the anterior segment of the eye and the retina.  相似文献   
4.
The fluorescence spectral fingerprint, also known as the excitation-emission matrix (EEM), is used to assess and visualize therapeutic drug photodegradation in combination with chemometrics. Examination of EEM-parallel factor analysis (PARAFAC) data showed that an individual component was easily separated from a mixture of photogenerated products of a heterocyclic pharmacophore, in this case, phenothiazine drugs (PTZs). Detailed investigations of both structure–EEM relationships and kinetics revealed that the components extracted from EEM–PARAFAC could be quantitatively attributed to such photogenerated products as phenothiazine sulfoxide and carbazole derivatives. EEM in combination with principal component analysis (PCA) could be used as a mapping tool to visualize information of the photodegradation process of PTZs. We also assessed the photostability of various types of PTZs containing side chains by using validated EEM–PARAFAC methodology.

Drug quality and assurance changes with time under the influence of a variety of environmental factors, such as light, temperature, and moisture.  相似文献   
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Scrub typhus has struck back, albeit with renewed vigour, impacting areas with previously known endemicity as also impressing newer expanses. It is not surprising, therefore, that Scrub typhus has emerged as a leading cause of public health concern globally as well as in India, but are we ready to take on the challenge?Over the last decade, there has been a global increase in the number of outbreaks of Scrub typhus, be it the military occupied areas or the civil population at large. The innumerable outbreaks of Scrub typhus, although disconcerting, have nonetheless contributed phenomenally towards better understanding of the dynamics of scrub typhus. There have been significant contributions to awareness of the disease amongst medical professionals, scrub typhus as a cause of Acute Undifferentiated Febrile Illness (AUFI) and newer clinical manifestation – Acute Encephalitis Syndrome (AES), availability and advances in diagnostics and management, man-vector-pathogen interactions, new records of Leptotrombidium species, newer vectors and Orientia species.Antigenic diversity and the varied clinical presentation of scrub typhus, absence of scrub typhus surveillance system and a lack of political will to recognize the disease as one of the important reemerging public health problem are areas seeking concerted deliberations and actions so that the challenges posed by scrub typhus can be addressed.  相似文献   
7.
Although the mortality rates of gastric cancer (GC) are gradually declining, gastric cancer is still the fourth leading cause of cancer-related death worldwide. This may be due to the high rate of patients who are diagnosed with GC at advanced stages. However, in countries such as Japan with endoscopic screening systems, more than half of GCs are discovered at an early stage, enabling endoscopic resection (ER). Especially after the introduction of endoscopic submucosal dissection (ESD) in Japan around 2000, a high en bloc resection rate allowing pathological assessment of margin and depth has become possible. While ER is a diagnostic method of treatment and may not always be curative, it is widely accepted as standard treatment because it is less invasive than surgery and can provide an accurate diagnosis for deciding whether additional surgery is necessary. The curability of ER is currently assessed by the completeness of primary tumor removal and the possibility of lymph node metastasis. This review introduces methods, indications, and curability criteria for ER of EGC. Despite recent advances, several problems remain unsolved. This review will also outline the latest evidence concerning future issues.  相似文献   
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Background The aim of this study was to analyze clinical and anatomical factors affecting the pathologic quality of the resected specimen after total mesorectal excision (TME) for rectal cancer. Methods A total of 100 patients who underwent TME for mid or low rectal cancer were evaluated prospectively. MRI pelvimetry data (transverse diameter, obstetric conjugate, interspinous distance, sacrum length, and sacrum depth) were analyzed as anatomically affecting factors to postoperative specimen quality. Sex, body mass index (BMI), type of surgery, tumor size, and tumor distance from the anal verge were analyzed as clinically affecting factors. The gross judgment of resected specimen, circumferential resection margin and the number of harvested lymph nodes were used to access postoperative specimen quality. Results The univariate and multivariate analysis showed that narrow obstetric conjugate and shorter interspinous distance were related to the inadequate quality of the mesorectum in the specimen (P = 0.022, P = 0.030). Interspinous distance was a predicting factor of a positive circumferential resection margin (P = 0.007). There were no clinical factors affecting the inadequate quality of the mesorectum or positive circumferential resection margin. Moreover, there were no clinico-anatomical factors affecting the number of harvested lymph nodes after TME. Conclusion Narrow obstetric conjugate and shorter interspinous distance were factors leading to poor postoperative specimen quality. Rectal cancer patients with narrow obstetric conjugate or shorter interspinous distance should be considered as high-risk patients with regard to specimen quality, which is in turn related to oncological outcome.  相似文献   
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