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101.
Torsion of a spermatocele on its pedicle is an extremely rare clinical condition that mimics acute testicular torsion. This rare condition has not been well characterized. Here, we report a case of torsion of a spermatocele. The present case is the 5th case of torsion of a spermatocele and the first report in a patient with a history of scrotal trauma. A tender cystic mass adjacent to the normally appearing testicle in the scrotum is highly significant for the differentiation from other types of acute scrotum. Torsion of a spermatocele should be considered a differential diagnosis of acute scrotum in adolescents and adults.  相似文献   
102.
A variety of immunocytochemical techniques are now widely used for the electron and light microscopic examination of biological samples. They are employed routinely for investigating the role of certain proteins in nervous tissue. Immunoelectron microscopic studies require the tissue to be fixed and embedded in a solid support, which may disrupt cellular structures and destroy crucial antigens. A technique of post-embedding with LR white resin has been developed, and it has been shown that certain antigens tolerate fixation with glutaraldehyde. In this study, we optimized a previous post-embedding method using low-water-miscible low-temperature embedding resin (LR white) to immunostain MBP, P0, NF and S100 proteins in peripheral nerves fixed with a relatively high concentration of glutaraldehyde found to be compatible with the morphology of normally compacted nerve fibers from humans and adult animals. The main difference in the procedures described here from previous ones is the elimination of vibratome sectioning, rendering this immunostaining technique more accessible to neuropathological laboratories using standard equipment for the ultrastructural study of peripheral nerves. It may prove of value for localization and quantification of these proteins in normal and pathological conditions.  相似文献   
103.
PURPOSE: This article focuses on understanding epidemiological features of alveolar echinococcosis and discussing its prevention and control, especially from a viewpoint of the ecosystem and risk management. METHOD: Publications on alveolar echinococcosis throughout the world were systematically reviewed with special reference to ecology, epidemiology and countermeasures. RESULTS: Alveolar echinococcosis, caused by accidental infection with larva of the parasite Echinococcus multilocularis is fatal to humans unless diagnosed at an early stage. No effective control measures have been identified so far because it is difficult to fully understand the ecology of the parasite and its intermediate and definitive hosts. It is also not easy to determine the precise infection route to humans mainly because of the long latent period. In Hokkaido, infection rates among red foxes have recently risen even in low endemic districts. Not only stray and domestic dogs but also some pigs in Hokkaido have been found to be infected. While the number of reported human cases is still small, around 10 cases per year, local residents seem to be threatened with the risk of infection. DISCUSSION AND CONCLUSIONS: We predict that the incidence of alveolar echinococcosis among humans in Japan will increase in the near future if no effective preventive measures are conducted. In addition, Echinococcus multilocularis infection has the potential to affect the economy of Hokkaido because of its impact on the agricultural and tourist industries. Well-designed epidemiological surveys are therefore urgently required, in the context of ecosystem and risk management prior to large outbreaks. International collaboration is also desired.  相似文献   
104.
Methanol and chloroform extracts were prepared from various parts of four plants collected in Mali: Guiera senegalensis (Gmel.) Combretaceae, Feretia apodanthera (Del.) Rubiaceae, Combretum micranthum (Don.) Combretaceae, Securidaca longepedunculata (Fres.) Polygalaceae and two plants -collected in Sao Tome: Pycnanthus angolensis (Welw.) Myristicaceae and Morinda citrifolia (Benth.) Rubiaceae were assessed for their in vitro antimalarial activity and their cytotoxic effects on human monocytes (THP1 cells) by flow cytometry. The methanol extract of leaves of Feretia apodanthera and the chloroform extract of roots of Guiera senegalensis exhibited a pronounced antimalarial activity. Two alkaloids isolated from the active extract of Guiera senegalensis, harman and tetrahydroharman, showed antimalarial activity (IC(50) lower than 4 microg/mL) and displayed low toxicity against THP1. Moreover, the decrease of THP1 cells in S phase of the cell cycle, after treatment with harman and tetrahydroharman, was probably due to an inhibition of total protein synthesis.  相似文献   
105.
Angiogenesis is an indispensable prerequisite for the progression and metastasis of solid malignancies. Tumor angiogenesis appears to be governed by alterations of tumor suppressor or oncogenes operant in a broad range of tumors. We have addressed this issue in neuroblastoma, a malignancy characterized by the near-exclusive amplification and overexpression of the N-Myc oncogene. Here, we report that N-Myc overexpression results in down-regulation of interleukin-6 (IL-6) and that IL-6 is an inhibitor of endothelial cell proliferation and VEGF-induced rabbit corneal angiogenesis. STAT3 is instrumental for IL-6 activity as infection with adenoviruses expressing a phosphorylation deficient STAT3 mutant renders endothelial cells insensitive to the antiproliferative action of IL-6. Finally, though IL-6 does not influence neuroblastoma cell growth, IL-6-expressing xenograft tumors in mice exhibit reduced neovascularization and suppressed growth. Our data shed new light on the mechanisms by which N-myc oncogene amplification enhances the malignant phenotype in neuroblastomas.  相似文献   
106.
The first case of a ventrally exophytic pontine glioma with extensive and dense calcification is reported. A 10-year-old boy presented with a generalized seizure. The skull radiogram and CT scan showed a dense area of calcification, revealed by MRI as the core of a ventrally exophytic tumor. The pathologic diagnosis was fibrillary astrocytoma.  相似文献   
107.
We report here the muscle MRI findings in two patients with human T-cell lymphotropic virus type I-associated myelopathy (HAM). It is known that thigh muscles are vulnerable in HAM patients, but detailed information about the affected muscles has not been available. Muscle MRI findings of these patients showed that thigh muscles, especially adductor magnus, and semimembranosus muscles were severely affected, but lower leg muscles were comparatively preserved. In these affected muscles, neurogenic changes were observed by EMG. We concluded that muscle MRI is very useful to estimate the affected muscles in HAM patients.  相似文献   
108.
We describe a case of false aneurysm due to loosening of the anastomotic sutures 5 years after graft replacement for subacute type A aortic dissection. Leakage from the graft was controlled by tightening the suture slack indicating that suture loosening was the cause of the aneurysm. The mechanism was probably the progressive thinning of the edematous swollen aortic wall over the years causing the sutures to loosen.  相似文献   
109.
BACKGROUND: Radiation-induced stomatitis is one of the adverse effects of total body irradiation(TBI). We examined the usefulness of oral polaprezinc as a preventive drug for stomatitis. PATIENTS AND METHODS: The present study was conducted with 19 patients who were diagnosed with hematologic malignancy and who underwent TBI as pretreatment for bone marrow transplantation, peripheral blood stem transplantation, or cord blood stem cell transplantation. Eleven patients ingested the suspension of polaprezinc and 2% carmellose sodium (carboxymethylcellulose sodium: CMC) beginning the day before TBI(P-CMC group), while the other eight patients did not ingest P-CMC(control group). The severity of stomatitis was assessed in each group during a four-weeks period. RESULTS: Stomatitis (Grade: > or = 3) developed in one of 11 patients in the polaprezinc group and in 4 of 8 patients in the control group(P = 0.046). The times at which stomatitis development ranged between weeks 1 and 2 after the onset of TBI in the two groups. No adverse reaction owing to the ingestion of P-CMC was observed. CONCLUSIONS: These results suggested the efficacy and safety of polaprezinc as a preventive drug for radiation-induced stomatitis.  相似文献   
110.
We report on a Japanese family of four generations with an autosomal dominant precocious osteoarthropathy. The cardinal clinical manifestations of affected individuals were painful weight-bearing large joints, which started in late childhood or adolescence. The radiological hallmarks included coxa plana, mild epiphyseal dysplasia of the knee, and round talar domes with tibiotalar slant in childhood, which evolved into degenerative joint diseases in adulthood. The disease phenotype was cosegregated with a mutation of the cartilage oligomeric matrix protein (COMP) gene in the family members, who underwent molecular evaluation. COMP mutations have been reported in a mild form of multiple epiphyseal dysplasia (MED), Ribbing type, as well as allied disorders with more severe manifestations, such as MED Fairbank type and pseudoachondroplasia. Unlike previously reported cases with the Ribbing type, the present patients did not have short stature or brachydactyly. This report expands further the phenotypic variations of COMP defects.  相似文献   
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