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1.
A 32-year-old male presented with progressive weakness and numbness of both upper limbs of one-month duration. The patient had weakness and wasting of small muscles of both hands with weak grip. Sensory system revealed graded sensory loss to pain, temperature and touch in C5 to T1 distribution and vibration and joint position sense from C5 to C8 in the both upper limbs. There was areflexia in the upper limbs while there was no motor or sensory deficit in the lower limbs. The cortical potential on stimulation of posterior tibial nerve was prolonged on both sides. On MR imaging of the cervical spine there was iso to low intense lesion which was hyperintense on T2-weighted imaging along the dorsal aspect of the cord extending from C2 to C6 level. The axial images showed involvement of the posterior column. The serum vitamin B12 level was found to be low. The patient responded to parenteral cyanocobalamine therapy and the radiological lesion subsequently resolved.  相似文献   
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The theory of five elements is extensively used in traditional Chinese medicine. It is proposed that the theory of five elements was developed on the basis of the theory of elements, the law of contagion and the law of similarity which were prevalent in that era. The theory of elements spread in various forms all over the face of the globe. The law of contagion stated that objects, which at one time had been in continuity or juxtaposition, continued to exert an effect one upon the other. The internal organs were coupled probably on the basis of the law of contagion. The law of similarity stated that objects or circumstances which bear apparent similarity in form, shape, color or sequence of events, were considered to be fundamentally related. On the basis of the law of similarity the coupled internal organs were classified into five elements and the theory of five elements was compared with various things like seasons, color, tastes, emotions, etc. The theory of five elements is probably the earliest documented evidence correlating physiology with pathogenesis of diseases and a guideline for treatment of diseases.  相似文献   
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Patients with retinoblastoma have an increased risk of developing second primary tumors. Only a few examples of sinonasal small cell neoplasms developing after radiation therapy for retinoblastoma have been reported. We report one such case that developed 18 years after treatment for retinoblastoma. Histologic examination revealed a small, blue, round cell tumor without rosettes or cytoplasmic glycogen. Immunohistochemically, the tumor cells were positive for neuron-specific enolase, synaptophysin, and S-100 protein, but negative for epithelial and mesenchymal markers, suggesting that this was a primitive neuroectodermal tumor. Cytogenetic studies of this tumor failed to reveal the chromosome 13 abnormality typical of retinoblastoma and the t(11:22) translocation typical of the group of peripheral neuroepitheliomas.  相似文献   
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Amyloidosis has been increasingly recognized in association with renal failure and chronic hemodialysis. This report describes three patients who had long-term hemodialysis (between 7-18 years), in whom deposits developed of a new type of amyloid of beta 2-microglobulin origin. Beta 2-microglobulin amyloid (AB2M) was found in multiple organs, i.e., bone, subendocardium, gastrointestinal blood vessels, tongue, and carpal tunnel connective tissue. AB2M displayed characteristic amyloid features on conventional light and polarized microscopic examination after congo red staining. However immunostaining with anti-amyloid A protein, kappa, and lambda antisera were negative. The studied material reacted positively with beta 2-microglobulin antisera, identifying AB2M in all three cases. Ultrastructural study revealed an unusual curvi-linear fibrillar configuration. AB2M appears to be a new subtype of systemic amyloidosis secondary to renal failure and long-term hemodialysis.  相似文献   
5.
Distribution of Lewis(x) (Le(x)) and Lewis(y) (Le(y)) blood-group antigens was studied in nine formaldehyde-fixed, paraffin-embedded cholangiocarcinomas (CCs), 26 hepatocellular carcinomas (HCCs), and eight normal livers. All CCs, with one exception, expressed both Le(x) and Le(y) antigens on few or many cells. In HCCs Lex was expressed infrequently (8%), while Le(y) was detected in 31% of cases. Both markers, when present in HCCs, tended to be spotty. Fibrolamellar carcinomas and normal livers did not react with either Le(x) or Le(y) antigens; however, Le(y) antigen was observed occasionally in bile duct epithelial and ductular cells. In conclusion, inappropriate tissue distribution of Le(y) blood-group antigens was observed in CCs and, much less frequently, in HCCs. The high frequency of Le(x) antigen in CCs but not in HCCs may help in the differential diagnosis of these two tumors.  相似文献   
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Behçet syndrome (BS) is a unique type of vasculitis that affects veins and arteries of all sizes, leading to recurrent vascular events, mostly venous thrombosis. The prevalence of venous thromboembolism in BS patients ranges between 15 and 40%. Thrombosis is usually an early manifestation leading to diagnosis of BS in up to 40% of patients. BS is per se a model of inflammation-induced thrombosis. The primary autoimmune response activates lymphocytes that in turn produce a cytokine cascade that activates neutrophils, which modify the secondary structure of fibrinogen making it less susceptible to plasmin-induced lysis. This leads to endothelial dysfunction, platelet activation and overexpression of tissue factor leading to inflammatory thrombi, usually attached to the wall. The pathogenesis of thrombosis is especially relevant to direct the specific treatment, that is based on immunosuppression rather than anticoagulation. Superficial vein thrombosis (SVT) and deep vein thrombosis (DVT) are the most common form of thrombosis in BS, but thrombosis in atypical sites (cava vein, suprahepatic veins, intracardiac thrombus) and arterial involvement can also occur. We assessed the latest update of the European League Against Rheumatism recommendations for the management of BS. Vascular Behçet treatment is usually based of immunosuppressants, and the role of anticoagulation remains controversial. The use of interventional and surgical procedures should be carefully evaluated, due to the risk of triggering a vascular pathergy phenomenon.

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Knowledge of the factors regulating the rate of mRNA degradation, including postmortem delay, is important in determining the reliability of gene expression patterns in dermal tissue. Since RNA stability can be tissue dependent, this study evaluates the effect of postmortem interval on the integrity of total RNA or the levels of representative mRNA species in murine cutaneous tissue. Pieces of fresh skin tissue were excised for periods of 0-60 min from SKH-1 female hairless mice that were maintained at room temperature post-sacrifice. Total RNA was subsequently isolated and RNA integrity from each specimen was evaluated. Bioanalyzer profiles showed no apparent change in 28S/18S rRNA ratio or RNA integrity number at time points up to 60 min. Changes in mRNA expression levels of five selected genes were determined by real-time quantitative PCR. There were no statistical differences in the relative gene expressions of Ccnd1, Hif1alpha, cMyc and Cyr61 as a function of postmortem interval. Our data suggest that the molecular quality of cutaneous tissue is well preserved for at least 60 min after death, which can be regarded as important information for consideration of the order for tissue procurement in in vivo studies and acute ex vivo dermal studies.  相似文献   
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