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81.
Juvenile granulosa cell tumor (JGCT) of testis is extremely rare in childhood. It is considered a benign entity because metastasis has never been reported. Testicular-sparing surgery is the recommended treatment. We reported this case in a newborn who presented with unilateral scrotal swelling. Histopathology and immunohistochemistry confirmed JGCT. Follow-up at 6 months after surgery did not show any recurrence. Even though JGCT is very rare in childhood, it is one of the important differentials of newborn scrotal mass.  相似文献   
82.
1. Type-specific antipneumococcus immunity has been induced in rabbits by immunization with antigen prepared by combining a specific derivative of the capsular polysaccharide of Type III Pneumococcus with globulin from horse serum. 2. Rabbits immunized with this antigen acquire active immunity against infection with virulent Type III pneumococci. 3. The sera of the immune rabbits contain type-specific antibodies which precipitate the Type III capsular polysaccharide, agglutinate Type III pneumococci, and specifically protect mice against Type III infection. 4. The experimental data are discussed with reference to: (1) the concurrence in the immune sera of type-specific antibodies for Pneumococcus and precipitins for horse globulin; (2) the determining influence of the capsular polysaccharide on the specificity of the antigen as a whole; (3) the unity of the type-specific precipitins, agglutinins, and protective antibodies induced by a single compo of the pneu mococcus in chemical union with an unrelated, animal protein.  相似文献   
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BackgroundMeningiomas are the most common primary intracranial tumor in adults. Clinical care is currently guided by the World Health Organization (WHO) grade assigned to meningiomas, a 3-tiered grading system based on histopathology features, as well as extent of surgical resection. Clinical behavior, however, often fails to conform to the WHO grade. Additional prognostic information is needed to optimize patient management.MethodsWe evaluated whether chromosomal copy-number data improved prediction of time-to-recurrence for patients with meningioma who were treated with surgery, relative to the WHO schema. The models were developed using Cox proportional hazards, random survival forest, and gradient boosting in a discovery cohort of 527 meningioma patients and validated in 2 independent cohorts of 172 meningioma patients characterized by orthogonal genomic platforms.ResultsWe developed a 3-tiered grading scheme (Integrated Grades 1-3), which incorporated mitotic count and loss of chromosome 1p, 3p, 4, 6, 10, 14q, 18, 19, or CDKN2A. 32% of meningiomas reclassified to either a lower-risk or higher-risk Integrated Grade compared to their assigned WHO grade. The Integrated Grade more accurately identified meningioma patients at risk for recurrence, relative to the WHO grade, as determined by time-dependent area under the curve, average precision, and the Brier score.ConclusionWe propose a molecularly integrated grading scheme for meningiomas that significantly improves upon the current WHO grading system in prediction of progression-free survival. This framework can be broadly adopted by clinicians with relative ease using widely available genomic technologies and presents an advance in the care of meningioma patients.  相似文献   
85.
Tetrahedrites, due to their promising thermoelectric properties, are one of the materials being investigated for use in thermoelectric generators. One problem is the lack of n-type tetrahedrites, which would be beneficial for the design of tetrahedrite thermoelectric modules. Preliminary theoretical studies have shown that elements from groups I and II can be introduced into the structural voids of tetrahedrite, acting as donor dopants, and should enable n-type conductivity. Therefore, in this work, an attempt was made to obtain and study magnesium-doped tetrahedrites. A series of samples, MgxCu12Sb4S13, with different magnesium contents were obtained and their phase and chemical compositions were characterized. It was observed that the structural changes occurring upon doping indicate that Mg atoms are likely to be embedded in the structural voids. The experimental studies have been supported by electronic structure calculations indicating that the most likely location of Mg is in the structural voids at the 6b Wyckoff position. Seebeck coefficient and resistivity measurements showed that doping with Mg reduces the concentration of holes, which is consistent with the predicted donor character of the dopant. However, the introduction of magnesium in sufficient amounts to achieve n-type conductivity was not successful.  相似文献   
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87.
Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening condition characterized by an exaggerated but dysregulated immune response resulting in hyperinflammation, with a potential for progression to multiple organ dysfunction and failure. Infectious diseases, inflammatory disorders, malignancies and immunodeficiency syndromes are known triggers of HLH in adults. The present study reported the case of a middle-aged man with HLH triggered by B-cell lymphoma who was successfully treated with dexamethasone; etoposide, prednisone, vincristine, cyclophosphamide, hydroxy-doxorubicin and rituximab chemotherapy; and multiple intrathecal methotrexate with a good outcome.  相似文献   
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89.
BackgroundChronic obstructive pulmonary disease (COPD) is a complex and heterogeneous condition, in which taking into consideration clinical phenotypes and multimorbidity is relevant to disease management. Network analysis, a procedure designed to study complex systems, allows to represent connections between the distinct features found in COPD.MethodsNetwork analysis was applied to a cohort of patients with COPD in order to explore the degree of connectivity between different diseases, taking into account the presence of two phenotypic traits commonly used to categorize patients in clinical practice: chronic bronchitis (CB+/CB) and the history of previous severe exacerbations (Ex+/Ex). The strength of association between diseases was quantified using the correlation coefficient Phi (ɸ).ResultsA total of 1726 patients were included, and 91 possible links between 14 diseases were established. Although the four phenotypically defined groups presented a similar underlying comorbidity pattern, with special relevance for cardiovascular diseases and/or risk factors, classifying patients according to the presence or absence of CB implied differences between groups in network density (mean ɸ: 0.098 in the CB group and 0.050 in the CB+ group). In contrast, between‐group differences in network density were small and of questionable significance when classifying patients according to prior exacerbation history (mean ɸ: 0.082 among Ex subjects and 0.072 in the Ex+ group). The degree of connectivity of any given disease with the rest of the network also varied depending on the selected phenotypic trait. The classification of patients according to the CB/CB+ groups revealed significant differences between groups in the degree of conectivity between comorbidities. On the other side, grouping the patients according to the Ex/Ex+ trait did not disclose differences in connectivity between network nodes (diseases).ConclusionsThe multimorbidity network of a patient with COPD differs according to the underlying clinical characteristics, suggesting that the connections linking comorbidities between them vary for different phenotypes and that the clinical heterogeneity of COPD could influence the expression of latent multimorbidity. Network analysis has the potential to delve into the interactions between COPD clinical traits and comorbidities and is a promising tool to investigate possible specific biological pathways that modulate multimorbidity patterns.  相似文献   
90.
Psoriasis is a chronic inflammatory skin disease with autoimmune pathogenic characteristics and is caused by chronic inflammation, which results in uncontrolled keratinocyte growth and defective differentiation. The link between the gut microbiota and immune system regulation opened a novel angle to understand the pathogenesis of many chronic multifactorial diseases, including psoriasis. Current evidence suggests that modulation of the gut microbiota, both through dietary approaches and through supplementation with probiotics and prebiotics, could represent a novel therapeutic approach. The present work aims to highlight the latest scientific evidence regarding the microbiome alterations of psoriatic patients, as well as state of the art insights in terms of microbiome-targeted therapies as promising preventive and therapeutic tools for psoriasis.  相似文献   
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