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61.
62.
PURPOSE: Tumor hypoxia may be an important factor predicting relapse following radiation therapy. This study was designed to determine the relationship between the oxygenation parameters measured using a polarographic oxygen electrode, prior to and during treatment in patients with cervix cancer, and to assess these results with regard to patient survival. MATERIALS AND METHODS: Forty-three patients had pretreatment oxygen assays performed and measurements repeated following external beam radiation to a median dose of 50 Gy (range 26-52 Gy). Stage distribution showed 15 patients in Stage IB, 17 in Stage II, and 11 in Stage III. The median tumor size was 5 cm (range 3-10 cm). RESULTS: The median proportion of pO2 values <5 mm Hg (the HP5) was 41% following radiation, and the median pO2 was 12 mm Hg. These results were not significantly different from the pretreatment HP5 or pO2 of 37% and 12 mm Hg, respectively. Disease-free survival at 2 years was 50% in patients with posttreatment HP5 < or =50%, compared to 60% when posttreatment HP5 was >50% (p = 0.35). CONCLUSIONS: Unlike pretreatment results, tumour oxygenation measured following external radiation does not appear to be a useful predictive assay in patients with cervical cancer.  相似文献   
63.
Mutations in the trabecular meshwork induced glucocorticoid response protein (TIGR) or myocilin (MYOC) has recently been shown to cause juvenile onset primary open angle glaucoma (JOAG). In this study, we identified two new mutations (Asp380Ala and Ser502Pro) in two British families and another (Pro370Leu) in a French-Canadian family. These mutations were not present in a total of 106 normal chromosomes. In another Turkish family with JOAG, we also detected a sequence variant that was proven to be an amino acid polymorphism (Arg76Lys). No other sequence changes were found in the entire coding region and splice junctions of the TIGR/MYOC gene in this family. However, it is still possible that mutations either in the TIGR promoter or in another neighbouring gene could cause glaucoma in this JOAG family. Our results confirm the role of the TIGR/MYOC gene in the aetiology of the JOAG phenotype.  相似文献   
64.
The Sense of Coherence Scale is used frequently world-wide and is thought to be appropriate to any population. The purpose of this study was to highlight some of the potential limitations of the scale. Fifteen members of the Pentecostal Movement described several difficulties in completing the scale, especially items measuring manageability and comprehensibility. The following three statements indicate the nature of their interpretation of the items and the ambiguity of their answers as they argued that: (1) the concept of 'I' was interpreted as 'I and God', (2) it is not necessary to understand everything in life, because it is enough that God understands, and (3) life is meaningful in itself because of the salvation. According to this interpretation of the items, every proposed answer could be suitable and consequently, the scores can readily be misconstrued. Many of the respondents proposed additions or changes in the wording to make the scale more suitable. The strong ego-centred items seem to be inappropriate for the participants in this study and other populations might also be confronted with similar difficulties.  相似文献   
65.
This paper will explore the delivery of mental health nursing care within a neo-liberal model of mental health care delivery in New Zealand. Mental health nursing as a socially constructed activity occurs within a particular political context, which determines its role and function. This environment determines the nature of the nurse-patient relationship which is integral to the role of mental health nurses. Critical analysis of the New Zealand Government's neo-liberal health policies will be conducted to explore their effect on mental health care delivery and the nurse-patient relationship. Some of the ideologies and values maintained by current dominant discourses within nursing and the State are discussed. To establish therapeutic partnerships with service-users, mental health nurses are urged to critically analyse their practice and the context in which it occurs.  相似文献   
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Adding sweeteners to ethanol solutions is a common method of inducing rats to consume ethanol. However, it has usually been assumed that it is the sweet taste and/or the calories contained in the sweet solution that controls consumption. The present experiment examined the role of ethanol in controlling responding reinforced by ethanol or an ethanol/sucrose mixture compared with sucrose solutions of various concentrations. After initiation to self-administer 10% (v/v) ethanol using the sucrose-substitution method, rats were trained to respond under a concurrent VI 5" VI 5" schedule. During one condition, responding on one lever was reinforced by the presentation of 10% ethanol, and responding on a second lever was reinforced by water or one of the following sucrose solutions: 1% (w/v), 1.5%, 2%, 2.5%, 3%, and 5%. During a subsequent condition, responding reinforced by a 10% ethanol/2% sucrose mixture was compared under the concurrent schedule with responding reinforced by water, 2%, 2.5%, 3%, 5%, or 10% sucrose (w/v). The results indicated that the ethanol or ethanol/sucrose mixture maintained more responding than did sucrose solutions that were sweeter. Data support the conclusion that, after initiation, the taste and/or pharmacological effects of ethanol had become an important component of the reinforcing stimulus independent of the sweetener.  相似文献   
68.
Adopting a high-throughput combinatorial approach, a compositionally graded Ti–xAl (0 ≤ x ≤ 8 wt%) specimen was prepared to conduct a rapid systematic investigation of the influence of composition and exposure time on the oxidation performance of the titanium-rich section of the binary Ti–Al system. The compositionally graded specimen was solution heat treated and subjected to oxidation tests at 650 °C for different exposure times. The morphology, structure, and composition of the oxide scale as well as the microstructural changes in the base material were studied across the entire composition range, using a suite of characterization techniques. The observations revealed the presence of Al2O3 in the topmost layer of the oxide scale in addition to TiO2, indicating its early formation during oxidation. An increase in Al concentration improves the scaling rate of Ti; however, this is observed only for extended exposure times (i.e., 50 and 100 h), and a parabolic oxidation law is obeyed in the composition-time domain. The formation of the α2 phase (Ti3Al) also takes place for relatively higher Al contents (i.e., 8 wt%).  相似文献   
69.
This work presents a monolithic integrated reconfigurable active circuit consisting of a W‐band RF micro‐electro‐mechanical‐systems (MEMS) Dicke switch network and a wideband low‐noise amplifier (LNA) realized in a 70 nm gallium arsenide (GaAs) metamorphic high electron mobility transistor process technology. The RF‐MEMS LNA has a measured gain of 10.2–15.6 dB and 1.3–8.2 dB at 79–96 GHz when the Dicke switch is switched ON and OFF, respectively. Compared with the three‐stage LNA used in this design the measured in‐band noise figure (NF) of MEMS switched LNA is minimum 1.6 dB higher. To the authors’ knowledge, the experimental results represent a first time demonstration of a W‐band MEMS switched LNA monolithic microwave integrated circuit (MMIC) in a GaAs foundry process with a minimum NF of 5 dB. The proposed novel integration of such MEMS switched MMICs can enable more cost‐effective ways to realize high‐performance single‐chip mm‐wave reconfigurable radiometer front‐ends for space and security applications, for example. © 2015 Wiley Periodicals, Inc. Int J RF and Microwave CAE 25:639–646, 2015.  相似文献   
70.
The effects of the addition of calcium carbonate (CC) and hydroxyapatite (HA) in chitosan-based biocomposites were studied keeping in mind their potential use as bone adhesives. The formation of coordination bonds between calcium ions and chitosan amino groups was evident, producing ionic cross-links between chitosan macromolecules, which changed chitosan gelation mechanisms, gel strengths, and adhesiveness into bone surfaces; CC concentration is a key factor in these phenomena. A formulation with 2% chitosan and 4% of both CC and HA showed the most promising performance having high levels of adhesion to bone surfaces (0.27?MPa) and a cohesive mode of failure.  相似文献   
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