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Journal of Neuro-Oncology - Primary central nervous system lymphoma (PCNSL) is a subtype of non-Hodgkin’s lymphoma that involves the brain, spinal cord, or leptomeninges, without evidence of...  相似文献   
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Continuing our studies of traditional medicine, as used in rural areas of Baja California Sur, now we wish to report on the medicinal uses of 49 more plants. Some of the more complex recipes of these medicinal plants, are discussed in the present paper. The information presented here was collected in the Municipio of Los Cabos and part of the Municipio of La Paz, B.C.S., Mexico.  相似文献   
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Chemotherapeutic agents have been used for the treatment of patients with osteosarcoma (OS). However, inherent or acquired resistance to these agents is a serious problem in the management of OS patients. The emergence of the multidrug resistance (MDR) phenotype in cancer cells is often associated with the overexpression of P-glycoprotein, encoded by the multidrug resistance gene MDR-1. The administration of some of the most common chemotherapeutic agents to these cells becomes ineffective because of their P-gp-driven efflux from the cell. Apo2L/TRAIL is a member of the tumor necrosis factor (TNF) family of cytokines that is considered to induce death of cancer cells but not normal cells. Its powerful apoptotic activity is mediated through its cell surface death domain-containing receptors, TRAIL-R1/DR4 and TRAIL-R2/DR5, which in turn spread the signal in the cytosol through the activation of the caspase cascade. The Akt/PKB kinase is an important cell survival protein which is regulated by D3-phosphoinositides. High Akt expression and activity levels are well documented in many types of tumors, which very often show an altered PI3-K/Akt/PTEN pathway. In this study the U2OS human osteosarcoma cell line and its multidrug resistant (MDR) subline that overexpresses MDR-1 gene, MDR-U2OS, have been analyzed for their responsiveness to TRAIL. In conflict with the presence of active DR4 and DR5 receptors in both clones, U2OS cells exhibited only a low responsiveness to TRAIL, while the MDR-U2OS subline did exhibit a marked TRAIL sensitivity. An analysis of the post-receptor events showed that TRAIL responsiveness correlates with a reduced expression of endogenous Akt. In fact, expression in MDR-U2OS cells of a constitutively active Akt strongly decreased their sensitivity to TRAIL. The identification of Akt as a key modulator of TRAIL responsiveness could help to design TRAIL-based combinations for treatment of osteosarcoma. Moreover, the discovery that multidrug resistant osteosarcomas are highly sensitive to TRAIL-induced apoptosis indicates TRAIL as a new candidate for the treatment of multidrug resistant bone malignancies.  相似文献   
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The ultrastructure of the myoneural junctions in the body wall muscles has been studied in Branchiobdella pentodonta Whit. A single junctional type has been found. Within the terminal axon there are two types of vesicles, which differ in number, size and electron opacity. The junctional gap contains the basement membrane. The post-junctional membrane displays concave patches on which slender projections arising from the outer lamina of the sarcolemma extend into the junctional gap. These concave patches overlie a cytoplasmic lamina made up of electron dense material.  相似文献   
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Lymphocyte subpopulations were studied in 20 hypertransfused patients with beta-thalassaemia major, some of whom had been splenectomised. B-lymphocytes were normal but T-lymphocytes were decreased in all patients. The T-cell count was lower in the splenectomised patients than in the nonsplenectomised ones. In the former, the active rosette-forming lymphocytes were also diminished, but the difference was not significant. In all patients the percentage of null cells was greater and the activity of K-cells increased compared with controls.  相似文献   
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OBJECTIVE: To evaluate whether disagreements in reporting child behavior problems between biological parents and foster parents and teachers are related to depressive symptoms in the biological parent. METHOD: Child Behavior Checklists and Teacher's Report Forms were completed by parents, foster parents, and teachers on 95 foster children between ages 5 and 16 during 1990-1991. Depressive symptoms in biological parents were assessed using the Center for Epidemiologic Studies Depression Scale. Structural equation modeling was used to estimate the relation between parental depressive symptoms and the discrepancies between their reports and those of two other informants. RESULTS: In both the internalizing and externalizing behavior models, a significant relation was found between parents' depressive symptoms and their discrepancies in reporting, but not with child behavior. This relation was stronger for internalizing than externalizing models. CONCLUSIONS: Using foster parents (and teachers) as informants offered a unique opportunity to view the reports of biological parents in comparison to two independent reports. Foster parents have a similar observational situation as biological parents but bring a less emotionally invested perspective to behavior observation, even when they are relatives. It is likely that depressive symptoms in parents distort their reports of their children's behavior. Clinicians would be wise to supplement parental with other informant reports.  相似文献   
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OBJECTIVE: The pressure-volume (P/V) curve has been proposed as a tool to adjust the ventilatory settings in cases of acute respiratory distress syndrome (ARDS). The aim of this study was to test the influence of P/V tracing methodology on the presence and value of the upper inflection point (UIP). METHODS: In 13 medical ARDS patients, the interruption and the automated low flow inflation methods were compared while the patients were ventilated at conventional (10-12 ml/kg) and at low (5-6 ml/kg) tidal volume (Vt). Two levels of inspiratory flow and insufflation time were used (3 and 6 s). RESULTS: No significant difference in UIP was found between the static and the dynamic methods, whatever the flow used. At Vt 10-12 ml/kg, the static and dynamic UIPs were 22.4 +/- 4.4 cmH(2)O and 22.1 +/- 4.5 cmH(2)O ( p = 0.86), respectively; at Vt of 5-6 ml/kg, the static and dynamic UIPs were 26.6 +/- 4.1 cmH(2)O and 25.5 +/- 5 cmH(2)O ( p = 0.34), respectively. Significant differences in UIP were found, in the static and dynamic conditions, between the two levels of Vt ( p < 0.005): it was lower with the higher Vt, suggesting that UIP is dependent on previous tidal alveolar recruitment. CONCLUSION: Interruption and continuous flow techniques gave similar results, but the previous Vt influences the pressure value of the UIP.  相似文献   
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We studied nine Italian families with a pure form of autosomal dominant spastic paraplegia (ADHSP) to assess the frequency of mutations in the SPG4 gene. We observed marked intrafamilial variability in both age-at-onset and clinical severity, ranging from severe congenital presentation to mild involvement after age 55 years to healthy carriers of the mutation after age 70. Four of nine probands harboured SPG4 mutations, We identified three new SPG4 mutations, all predicting a loss-of-function with apparently important consequences for spastin function. RT-PCR studies predict loss-of-function as a possible mechanism leading to spastin-related HSP. The current study expands the spectrum of allelic variants in SPG4, confirming their pathological significance in pure AD-HSP and suggesting implications for the presumed function of spastin. Received: 15 December 2000, Received in revised form: 29 May 2001, Accepted: 18 June 2001  相似文献   
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