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31.
Lung cancer, of which non-small cell carcinoma is the most common, has been a significant therapeutic challenge for decades and will remain so for decades to come. Despite its prevalence, progress in the management of non-small cell lung cancer has been relatively slow. This is in part due to the pessimism of most physicians treating this disease, which has resulted in a relatively lackadaisical attitude with regards to clinical trials when compared to other solid tumours like breast or colorectal cancers. Nevertheless, the past decade has seen significant progress, specifically with regards to the management of locally advanced disease. Chemotherapy, though shown to be biologically active in non-small cell lung cancer, is considered an ineffective palliative tool in the setting of metastatic disease due to its toxicities and the "less than encouraging" response rates generated by the cisplatin-based combination regimen which is generally considered to be the most active currently available. The advent of new active agents such as paclitaxel and vinorelbine which are potentially less toxic may change this view. Conversely, the response rate of locally advanced disease to chemotherapy is significantly higher and this has resulted in numerous multimodality trials of neoadjuvant chemotherapy prior to surgery and/or radiation. To date, a number of randomised trials have shown that this approach can result in significant survival benefit for patients with locally advanced disease. An alternative approach makes use of the potential synergism between certain chemotherapeutic agents (such as cisplatin) and radiation when used concurrently. However, data on concurrent chemoradiotherapy in locally advanced disease have been largely based on single-arm studies and are inconclusive. Three randomised trials on concurrent chemoradiotherapy have been shown benefit for the use of combined modality in locally advanced disease. Hence, treatment of locally advanced disease should include chemotherapy as part of the combined modality approach. However, the optimal sequencing of these modalities would require well-designed randomised trials to determine. 相似文献
32.
MJ Christie 《Canadian Metallurgical Quarterly》1976,2(5):227-229
When palmar eccrine sweat glands are inactive the potential difference between palmar skin and a prepared forearm site is a function of the ratio of external (electrode electrolyte) and internal (tissue fluid) potassium concentrations. Evidence indicates that this "basal" palmar skin potential changes systematically with changes in ECF K+, and may be used to monitor such shifts, as, for example, in stress. 相似文献
33.
One hundred forty-nine inpatients within a maximum security psychiatric facility were assessed with the Psychopathy Checklist: Screening Version (PCL:SV; S. D. Hart, D. N. Cox, & R. D. Hare, 1995). Within the total sample, 68% had a psychotic disorder and 30% met criteria for psychopathy. Using confirmatory factor analysis, the authors tested the 2-factor PCL:SV model of psychopathy and recent 3- and 4-factor models. Results indicated good fit for each model, with the 4-factor model showing best overall fit. Structural equation modeling was used to determine which psychopathy factors predicted 6-month follow-up of inpatient aggression. The 2-, 3-, and 4-factor models, respectively, accounted for 16%.27%. and 3l% of the variance in aggression. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
34.
The influence of pH and heating time at 80 °C on the final stage (conversion to the calcium salt) of the formation of the metal salt azo pigment, CI Pigment Red 48:2, has been investigated. A series of systematically prepared pigment samples were characterized by transmission electron microscopy, X-ray powder diffraction, surface area measurement and a detailed nitrogen adsorption–desorption isotherm investigation. Significant differences in the crystal sizes and morphologies and in the crystal growth patterns were observed. The colour and lightfastness properties in air-drying alkyd paints are correlated with the physical property data. 相似文献
35.
Mallory Batty Rachel Pugh Ilampirai Rathinam Joshua Simmonds Edwin Walker Amanda Forbes Shailendra Anoopkumar-Dukie Catherine M. McDermott Briohny Spencer David Christie Russ Chess-Williams 《International journal of molecular sciences》2016,17(8)
This review evaluates the role of α-adrenoceptor antagonists as a potential treatment of prostate cancer (PCa). Cochrane, Google Scholar and Pubmed were accessed to retrieve sixty-two articles for analysis. In vitro studies demonstrate that doxazosin, prazosin and terazosin (quinazoline α-antagonists) induce apoptosis, decrease cell growth, and proliferation in PC-3, LNCaP and DU-145 cell lines. Similarly, the piperazine based naftopidil induced cell cycle arrest and death in LNCaP-E9 cell lines. In contrast, sulphonamide based tamsulosin did not exhibit these effects. In vivo data was consistent with in vitro findings as the quinazoline based α-antagonists prevented angiogenesis and decreased tumour mass in mice models of PCa. Mechanistically the cytotoxic and antitumor effects of the α-antagonists appear largely independent of α 1-blockade. The proposed targets include: VEGF, EGFR, HER2/Neu, caspase 8/3, topoisomerase 1 and other mitochondrial apoptotic inducing factors. These cytotoxic effects could not be evaluated in human studies as prospective trial data is lacking. However, retrospective studies show a decreased incidence of PCa in males exposed to α-antagonists. As human data evaluating the use of α-antagonists as treatments are lacking; well designed, prospective clinical trials are needed to conclusively demonstrate the anticancer properties of quinazoline based α-antagonists in PCa and other cancers. 相似文献
36.
Treatment of Acid Leachate from Coal Discard using Calcium Carbonate and Biological Sulphate Removal
J.?P.?MareeEmail author G.?Strobos H.?Greben E.?Netshidaulu E.?Steyn A.?Christie P.?Günther F.?B.?Waanders 《Mine Water and the Environment》2004,23(3):144-151
Abstract.
An integrated approach is proposed for treating acidic coal discard leachate, consisting of CaCO3 handling and dosing, CaCO3-neutralization, and biological sulphate removal. It was found that: powdered CaCO3 can be slurried to a constant density and used to neutralize the acid water, remove Fe (II), Fe (III), and Al, and partially remove the sulphate (to saturation level); biological sulphate removal can be used to lower the sulphate to less than 200 mg/L using ethanol as the carbon and energy source; CO2 produced during calcium carbonate treatment can be used for H2S-stripping and; H2S gas recovered in the sulphate removal stage can be used for iron removal. 相似文献
37.
The single crystal X-ray structures of three structurally related azonaphtharylamide pigments are reported. Two azo pigments derived from 4-amino-3-nitrotoluene as diazo component (1a and b) crystallize in the centrosymmetric space group P21/c while the third (1c), an analogue of 1b but derived from 2,5-dichloroaniline as diazo component, crystallizes in the chiral space group P212121. The compounds adopt the ketohydrazone tautomeric forms with intramolecular, but no intermolecular, hydrogen bonding. The application performance of the products is discussed in relation to the molecular and crystal structures. X-ray powder diffraction, supported by FTIR spectroscopic and DSC analysis, demonstrate that pigment 1a shows polymorphism. The application performances of the two polymorphs of this pigment are compared. 相似文献
38.
Field Assessment of the Performance of a Ballasted Rail Track with and without Geosynthetics 总被引:1,自引:0,他引:1
Buddhima Indraratna Sanjay Nimbalkar David Christie Cholachat Rujikiatkamjorn Jayan Vinod 《Canadian Metallurgical Quarterly》2010,136(7):907-917
Understanding the complex mechanisms of stress transfer and strain accumulation in layers of track substructure under repeated wheel loading is essential to predict the desirable track maintenance cycle as well as the design of the new track. Various finite element and analytical techniques have been developed in the past to understand the behavior of composite track layers subjected to repeated wheel loads. The mechanical behavior of ballast is influenced by several factors, including the track confining pressure, type of aggregates, and the number of loading cycles. A field trial was conducted on an instrumented track at Bulli, New South Wales, Australia, with the specific aims of studying the benefits of a geocomposite installed at the ballast-capping interface, and to evaluate the performance of moderately graded recycled ballast in comparison to traditionally very uniform fresh ballast. It was found that recycled ballast can be effectively reused if reinforced with a geocomposite. It was also found that geocomposite can effectively reduce vertical and lateral strains of the ballast with obvious implications for improved track stability and reduced maintenance costs. 相似文献
39.
W Thongnoppakhun P Wilairat K Vareesangthip PT Yenchitsomanus 《Canadian Metallurgical Quarterly》1999,26(1):126-132
The peptidoglycan cortex of endospores of Bacillus species is required for maintenance of spore dehydration and dormancy, and the structure of the cortex may also allow it to function in attainment of spore core dehydration. A significant difference between spore and growing cell peptidoglycan structure is the low degree of peptide cross-linking in cortical peptidoglycan; regulation of the degree of this cross-linking is exerted by D,D-carboxypeptidases. We report here the construction of mutant B. subtilis strains lacking all combinations of two and three of the four apparent D, D-carboxypeptidases encoded within the genome and the analysis of spore phenotypic properties and peptidoglycan structure for these strains. The data indicate that while the dacA and dacC products have no significant role in spore peptidoglycan formation, the dacB and dacF products both function in regulating the degree of cross-linking of spore peptidoglycan. The spore peptidoglycan of a dacB dacF double mutant was very highly cross-linked, and this structural modification resulted in a failure to achieve normal spore core dehydration and a decrease in spore heat resistance. A model for the specific roles of DacB and DacF in spore peptidoglycan synthesis is proposed. 相似文献
40.
This paper defines a new denotational semantics for the language of Communicating Sequential Processes (CSP). The semantics
lies between the existing traces and failures models of CSP, providing a treatment of non-determinism in terms of singleton failures. Although the semantics does not represent a congruence upon the full language, it is adequate for sequential tests of non-deterministic
processes. This semantics corresponds exactly to a commonly used notion of data refinement in Z and Object-Z: an abstract
data type is refined when the corresponding process is refined in terms of singleton failures. The semantics is used to explore
the relationship between data refinement and process refinement, and to derive a rule for data refinement that is both sound
and complete.
Received October 2001
Revised September 2002, February 2003, June 2004 and October 2005
Accepted November 2005 by I. J. Hayes 相似文献