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91.
Aasim I. Padela Aisha Y. Malik Farr Curlin Raymond De Vries 《Developing world bioethics》2015,15(2):98-106
Contemporary clinical ethics was founded on principlism, and the four principles: respect for autonomy, nonmaleficence, beneficence and justice, remain dominant in medical ethics discourse and practice. These principles are held to be expansive enough to provide the basis for the ethical practice of medicine across cultures. Although principlism remains subject to critique and revision, the four‐principle model continues to be taught and applied across the world. As the practice of medicine globalizes, it remains critical to examine the extent to which both the four‐principle framework, and individual principles among the four, suffice patients and practitioners in different social and cultural contexts. Using the four‐principle model we analyze two accounts of surrogate decision making – one from the developed and one from the developing world – in which the clinician undertakes medical decision‐making with apparently little input from the patient and/or family. The purpose of this analysis is to highlight challenges in assessing ethical behaviour according to the principlist model. We next describe cultural expectations and mores that inform both patient and clinician behaviors in these scenarios in order to argue that the principle of respect for persons informed by culture‐specific ideas of personhood may offer an improved ethical construct for analyzing and guiding medical practice in a globalized and plural world. 相似文献
92.
A Johnson F A Blumenstock A B Malik 《Journal of applied physiology (Bethesda, Md. : 1985)》1983,55(5):1480-1485
We examined the effect of complement depletion on lung fluid and protein exchange after thrombin-induced pulmonary thromboembolization. Sheep were prepared with lung lymph fistulas to assess pulmonary transvascular fluid and protein dynamics. Studies were made in three groups: in group I (n = 5) pulmonary thromboembolization (PT) was induced by an iv infusion of thrombin (55.0 +/- 12.9 NIH U/kg); in group II (n = 6) cobra venom factor (CVF) was given ip (94.5 +/- 18.8 U/kg/day) for 2 days to deplete complement, and then thrombin (66.4 +/- 37.0 NIH U/kg) was infused to raise pulmonary vascular resistance to the same level as in group I; in group III (n = 10) left atrial pressure (Pla) was increased by 10-15 Torr in normal animals by inflation of a Foley balloon catheter. In group I, thrombin infusion caused an increase in pulmonary lymph flow (Qlym) with a gradual increase in the lymph-to-plasma protein concentration ratio (L/P). In complement-depleted sheep, thrombin caused a transient increase in Qlym, which was associated with a decrease in L/P. In group I an increase in Pla further increased Qlym but without a change in L/P, indicating an increase in lung vascular permeability to proteins; whereas in the decomplemented-thrombin sheep raising Pla increased Qlym but decreased L/P. Results in the latter group were similar to those obtained in normal animals after left atrial hypertension (group III). Therefore the complement system participates in the increase in lung vascular permeability following thrombin-induced microembolization. 相似文献
93.
Qaisara Pasha Salman A. Malik Nazia Shaheen Munir H. Shah 《Biological trace element research》2010,134(2):160-173
Trace elements including Al, Ca, Cd, Co, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Sb, Sr, and Zn were analyzed in the scalp hair
samples of women with malignant breast lesions, women with benign breast lesions, and healthy donors using atomic absorption
spectrophotometric method. In the scalp hair of malignant-tumor patients, the highest average concentration was shown by Ca
(1,187 μg/g), followed by Na (655 μg/g), Mg (478 μg/g), Zn (391 μg/g), Sr (152 μg/g), Fe (114 μg/g), and K (89.8), while in
the case of benign-tumor patients, the average estimated element levels were 1,522, 1,093, 572, 457, 217, 80.4, and 74.7 μg/g,
respectively. Most of the elements exhibited non-normal distribution evidenced by large spread, standard error, and skewness
values. Mean concentrations of Ca (634 μg/g), Zn (206 μg/g), Mg (162 μg/g), Fe (129 μg/g), and Na (82.1 μg/g) were noteworthy
in the scalp hair of healthy women. Average levels of Na, Sr, K, Cd, Co, Pb, Mg, Ca, Zn, Ni, Sb, and Mn were revealed to be
significantly higher in the hair of malignant and benign patients compared to the healthy women; however, Fe, Cu, Al, and
Cr were not significantly different in the scalp hair of the three groups. The quartile distributions of Ca, Cd, Co, Cr, K,
Mg, Mn, Na, Ni, Pb, Sb, and Sr revealed maximum spread in the scalp hair of malignant and benign groups; nevertheless, Al,
Cu, Fe, and Zn exhibited almost comparable quartile levels in the three groups. Strong correlation coefficients were found
between Fe and Cd, Al and Na, Mn and Sr, Co and Cr, Cd and Cr, Pb and K, Pb and Mn, Cu and Na, and Al and Fe in the scalp
hair of malignant-tumor patients, while Fe and K, Cd and Co, Na and Co, and Cr and Pb showed strong correlations in the scalp
hair of benign-tumor patients, both of which were significantly different compared with the healthy subjects. Multivariate
cluster analysis also revealed divergent clustering of the elements in the scalp hair of malignant and benign patients in
comparison with the healthy women. 相似文献
94.
Goubaeva F Ghosh M Malik S Yang J Hinkle PM Griendling KK Neubig RR Smrcka AV 《The Journal of biological chemistry》2003,278(22):19634-19641
We previously developed peptides that bind to G protein betagamma subunits and selectively block interactions between betagamma subunits and a subset of effectors in vitro (Scott, J. K., Huang, S. F., Gangadhar, B. P., Samoriski, G. M., Clapp, P., Gross, R. A., Taussig, R., and Smrcka, A. V. (2001) EMBO J. 20, 767-776). Here, we created cell-permeating versions of some of these peptides by N-terminal modification with either myristate or the cell permeation sequence from human immunodeficiency virus TAT protein. The myristoylated betagamma-binding peptide (mSIRK) applied to primary rat arterial smooth muscle cells caused rapid activation of extracellular signal-regulated kinase 1/2 in the absence of an agonist. This activation did not occur if the peptide lacked a myristate at the N terminus, if the peptide had a single point mutation to eliminate betagamma subunit binding, or if the cells stably expressed the C terminus of betaARK1. A human immunodeficiency virus TAT-modified peptide (TAT-SIRK) and a myristoylated version of a second peptide (mSCAR) that binds to the same site on betagamma subunits as mSIRK, also caused extracellular signal-regulated kinase activation. mSIRK also stimulated Jun N-terminal kinase phosphorylation, p38 mitogen-activated protein kinase phosphorylation, and phospholipase C activity and caused Ca2+ release from internal stores. When tested with purified G protein subunits in vitro, SIRK promoted alpha subunit dissociation from betagamma subunits without stimulating nucleotide exchange. These data suggest a novel mechanism by which selective betagamma-binding peptides can release G protein betagamma subunits from heterotrimers to stimulate G protein pathways in cells. 相似文献
95.
Morgan NV Gissen P Sharif SM Baumber L Sutherland J Kelly DA Aminu K Bennett CP Woods CG Mueller RF Trembath RC Maher ER Johnson CA 《Human genetics》2002,111(4-5):456-461
Meckel-Gruber syndrome (MKS), the most common monogenic cause of neural tube defects, is an autosomal recessive disorder characterised by a combination of renal cysts and variably associated features, including developmental anomalies of the central nervous system (typically encephalcoele), hepatic ductal dysplasia and cysts, and polydactyly. Locus heterogeneity has been demonstrated by the mapping of the MKS1locus to 17q21-24 in Finnish kindreds, and of MKS2 to 11q13 in North African-Middle Eastern cohorts. In the present study, we have investigated the genetic basis of MKS in eight consanguineous kindreds, originating from the Indian sub-continent, that do not show linkage to either MKS1 or MKS2. We report the localisation of a third MKS locus ( MKS3) to chromosome 8q24 in this cohort by a genome-wide linkage search using autozygosity mapping. We identified a 26-cM region of autozygosity between D8S586 and D8S1108 with a maximum cumulative two-point LOD score at D8S1179 ( Z(max)=3.04 at theta=0.06). A heterogeneity test provided evidence of one unlinked family. Exclusion of this family from multipoint analysis maximised the cumulative multipoint LOD score at locus D8S1128 ( Z(max)=5.65). Furthermore, a heterozygous SNP in DDEF1, a putative candidate gene, suggested that MKS3 mapped within a 15-cM interval. Comparison of the clinical features of MKS3-linked cases with reports of MKS1- and MKS2-linked kindreds suggests that polydactyly (and possibly encephalocele) appear less common in MKS3-linked families. 相似文献
96.
97.
Muhammad Shakeel Farhat Jabeen Rehana Iqbal Abdul Shakoor Chaudhry Sadia Zafar Muhammad Ali Muhammad Saleem Khan Adeel Khalid Samina Shabbir Muhammad Saleem Asghar 《Biological trace element research》2018,182(1):57-69
This study assessed the protective effects of Cinnamomum cassia (cinnamon) bark extract in rats exposed to titanium dioxide nanoparticles or titanium dioxide bulk salt. For in vivo evaluation of the ameliorative role of the cinnamon extract, the experimental groups were orally administered with the cinnamon extract at different dose levels (50 or 100 or 150 mg/kg bodyweight) along with the subcutaneous injections of 150 mg/kg bodyweight titanium dioxide nanoparticles or titanium dioxide bulk salt. The extract showed significant ameliorative role on the antioxidant system in response to elevated levels of titanium dioxide nanoparticles or titanium dioxide bulk salt-induced oxidative stress. It aided in the recovery of the antioxidant system as well as protective role in histological damages and some haematological parameters in the rat liver treated with titanium dioxide nanoparticles or titanium dioxide bulk salt. 相似文献
98.
Muhammad Aqib Fahim Nawaz Sadia Majeed Abdul Ghaffar Khawaja Shafique Ahmad Muhammad Asif Shehzad Muhammad Naeem Tahir Muhammad Aurangzaib Hafiz Muhammad Rashad Javeed Muhammad Habib-ur-Rahman Muhammad Munir Usmani 《Physiology and Molecular Biology of Plants》2021,27(5):1073
The present study involved two pot experiments to investigate the response of mung bean to the individual or combined SO42− and selenate application under drought stress. A marked increment in biomass and NPK accumulation was recorded in mung bean seedlings fertilized with various SO42− sources, except for CuSO4. Compared to other SO42− fertilizers, ZnSO4 application resulted in the highest increase in growth attributes and shoot nutrient content. Further, the combined S and Se application (S + Se) significantly enhanced relative water content (16%), SPAD value (72%), photosynthetic rate (80%) and activities of catalase (79%), guaiacol peroxidase (53%) and superoxide dismutase (58%) in the leaves of water-stressed mung bean plants. Consequently, the grain yield of mung bean was markedly increased by 105% under water stress conditions. Furthermore, S + Se application considerably increased the concentrations of P (47%), K (75%), S (80%), Zn (160%), and Fe (15%) in mung bean seeds under drought stress conditions. These findings indicate that S + Se application potentially increases the nutritional quality of grain legumes by stimulating photosynthetic apparatus and antioxidative machinery under water deficit conditions. Our results could provide the basis for further experiments on cross-talk between S and Se regulatory pathways to improve the nutritional quality of food crops.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12298-021-00992-6. 相似文献
99.
Daisylyn Senna Tan Yanpu Chen Ya Gao Anastasia Bednarz Yuanjie Wei Vikas Malik Derek Hoi-Hang Ho Mingxi Weng Sik Yin Ho Yogesh Srivastava Sergiy Velychko Xiaoxiao Yang Ligang Fan Johnny Kim Johannes Graumann Gary D. Stormo Thomas Braun Jian Yan Hans R. Schler Ralf Jauch 《Molecular biology and evolution》2021,38(7):2854
100.