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排序方式: 共有672条查询结果,搜索用时 31 毫秒
1.
Neuroimaging in Pineal Tumors 总被引:4,自引:0,他引:4
F Reis MD AV Faria MD PhD VA Zanardi MD PhD JR Menezes MD F Cendes MD PhD LS Queiroz MD PhD 《Journal of neuroimaging》2006,16(1):52-58
BACKGROUND AND PURPOSE: The authors report radiological findings in 11 tumors in the pineal region, which were histologically diagnosed as germinomas, pineocytomas pineoblastomas, ependymomas, teratomas, and astrocytomas. METHODS: Computed tomography (CT) was performed in seven patients and magnetic resonance imaging (MRI) was performed in all patients. RESULTS: CT showed a solid or solid/cystic mass with variable contrast enhancement. MRI showed a heterogeneous mass, with hypointense signal on T1 and iso/hyperintense signal on T2-weighted images (WI) and gadolinium enhancement. Extension to adjacent structures occurred in five patients and spread through the cerebral spinal fluid (CSF) in two. CONCLUSIONS: Pineal region tumors have no pathognomonic imaging pattern. MRI and CT are complementary in diagnosis and are important to determine localization, extension, and meningeal spread. 相似文献
2.
When tympanosclerosis involves the tympanic membrane or the lateral ossicles, treatment is usually straightforward and uncomplicated. When the stapes is involved, therapy is more controversial and may be more difficult. We report our results in 154 patients who underwent different surgical procedures for tympanosclerosis of the stapes. Followup was up to 10 years. Pure-tone average threshold was significantly improved (p < 0.05) in patients who underwent mobilization procedures or stapedectomy for definitive treatment. The air-bone gap was less than 20 dB at 6 months postoperative in 72% of patients and less than 30 dB in 90%. At 6 months, 2 years, and 5 years there were no statistically significant differences in hearing results between stapedectomy and mobilization patients, some of whom were followed for up to 10 years. No patient had a profound hearing loss after surgery. Surgical treatment for tympanosclerosis of the stapes is a safe procedure, with hearing results similar to those of surgery for other chronic ear diseases involving the ossicular chain. 相似文献
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Lawrence G. Lum Edith Burns Marleen M. Janson Paul J. Martin Bernadette R. Giddings Margaret C. Seigneuret Jan E. Noges Sandra C. Galoforo 《Journal of clinical immunology》1990,10(5):255-264
This investigation uses a system for inducing and detecting anti-tetanus toxoid antibody (anti-TT) synthesis to study specific antibody (Ab) synthesis by bone marrow mononuclear cells (MC). We measured the amounts of anti-TT secreted and the number of B cells secreting antibody (Ab). The ELISA plaque detects single B cells secreting specific Ab. The results show that (1) spontaneous anti-TT secretion by MC is higher than spontaneous anti-TT secretion by peripheral blood lymphocytes (PBL) using an ELISA plaque (P<0.01); (2) spontaneous anti-TT production by MC correlated with the serum anti-TT titers as measured by an ELISA (r=0.75,P=0.005); (3) two types of marrow B cells were identified—one that spontaneously secretes anti-TT and another that produces anti-TT after TT-stimulation; (4) the frequency of anti-TT-secreting B cells is higher in MC than in PBL; (5) the amount of Ab secreted per marrow B cell is not different from that secreted by a peripheral B cell; and (6) marrow B cells could be induced to produce anti-TTin vitro up to 10 months without added cytokines. These results show that bone marrow is a major repository for differentiated B cells that spontaneously produce Abs to maintain circulating Abs titers and for memory B cells that can be induced to produce specific Ab. 相似文献
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Laboratory support in the diagnosis of coagulation disorders 总被引:1,自引:0,他引:1
In spite of recent advances in knowledge concerning the detailed biochemistry of blood coagulation, the diagnosis of haemostatic disturbances remains an important problem of clinical judgement in many instances. Laboratory support relies initially on a series of screening tests designed to investigate the general nature of blood clotting. Recent interest in these aspects is centred on standardization and quality assurance of methods and results. Procedures have been recommended in an attempt to unify data. Several aspects of conventional laboratory investigations have been modified and the reliability of diagnostic information has been improved. Some relatively recent findings have extended the application to coagulation studies. For example, the discovery of protein C, a potent physiological inhibitor of blood coagulation, has clarified the nature of the clotting disorder in some patients with hereditary thrombosis disease. In addition, close analysis of plasma from patients with systemic lupus erythematosus has stimulated interest in the association between the haemostatic, neurological and immunological abnormalities recorded in these patients. More recently, sophisticated techniques for the diagnosis of many coagulation factor defects have been developed. Carrier detection of the sex-linked disorders is undertaken widely with reasonable success and reliable prenatal diagnosis procedures have been established in specialized centres. Unequivocal information regarding the diagnosis of carrier status in some families is obtained by the use of gene analysis and linked polymorphisms. Precise details of the genes for several clotting factors have been recorded. Future development in this field is likely to improve the clinical course of many coagulation disorders. 相似文献
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Corteling RL Li S Giddings J Westwick J Poll C Hall IP 《American journal of respiratory cell and molecular biology》2004,30(2):145-154
Elevation of the intracellular free Ca(2+) concentration regulates many functional responses in airway smooth muscle, including contraction, proliferation, adhesion, and cell survival. This increase in calcium can be achieved by a release from internal stores (sarcoplasmic reticulum) and/or entry across the cell membrane from the extracellular environment. The molecular identity of this calcium influx pathway in human airway smooth muscle (HASM) remains unclear. Functional studies using Fluo 4-loaded HASM suggest the presence of a histamine H(1) receptor-activated Ca(2+) entry pathway with characteristics similar to those seen with transient receptor potential (TRP) family homologs. Using a range of molecular and cell biological approaches we defined the expression pattern of transient receptor potential classics (TRPC) homologs in airway cells and tissue. Here we show that HASM and human bronchial epithelial cells both express TRPC1, -4, and -6, with HASM also expressing TRPC3 at the mRNA level. Identification of TRPC6 protein by western blot and confocal microscopy indicated that the protein is localized in specific cell types, suggesting that it plays an important role in regulating key functions in airway cells. These data demonstrate the expression of a range of TRPC homologs in the airway and the presence of a functional Ca(2+) entry pathway with characteristics typical of TRPC family members. TRPC homologs may provide an important novel target for the treatment of airway disease. 相似文献
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C R Yonker K D Caldwell J C Giddings J L Van Etten 《Journal of virological methods》1985,11(2):145-160
A virus (PBCV) from the symbiotic Chlorella-like algae of Paramecium bursaria has been characterized by sedimentation field flow fractionation (SdFFF). The method yields effective molecular weight M' (molecular weight X buoyancy factor) with a precision of better than 5% under a variety of experimental conditions. The value for M' is used to calculate true molecular weight values through combination with density values; densities were obtained from outside sources, from ultrasonic densitometry, and from sedimentation coefficients determined independently. The actual molecular weight is also determined through SdFFF analysis of the virus in carriers of different densities. Values for the particle diameter are obtained from SdFFF zone broadening studies. The various SdFFF characterization results are compared with molecular weight, particle size, and density values determined by conventional methods. 相似文献
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