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21.
Shejuty Shahreen Joyanta Banik Abdul Hafiz Shahnaz Rahman Anahita Tanzia Zaman Md Abu Shoyeb Majeedul H Chowdhury Mohammed Rahmatullah 《African journal of traditional, complementary, and alternative medicines》2012,9(2):287-291
Averrhoa carambola L. (Oxalidaceae), Ficus hispida L.f. (Moraceae), and Syzygium samarangense (Blume) Merr. & L.M. Perry (Myrtaceae) are three common plants in Bangladesh, the fruits of which are edible. The leaves and fruits of A. carambola and F. hispida are used by folk medicinal practitioners for treatment of diabetes, while the leaves of S. samarangense are used for treatment of cold, itches, and waist pain. Since scientific studies are absent on the antihyperglycemic effects of the leaves of the three plants, it was the objective of the present study to evaluate the antihyperglycemic potential of methanolic extract of leaves of the plants in oral glucose tolerance tests carried out with glucose-loaded mice. The extracts at different doses were administered one hour prior to glucose administration and blood glucose level was measured after two hours of glucose administration (p.o.) using glucose oxidase method. Significant oral hypoglycemic activity was found with the extracts of leaves of all three plants tested. The fall in serum glucose levels were dose-dependent for every individual plant, being highest at the highest dose tested of 400 mg extract per kg body weight. At this dose, the extracts of A. carambola, F. hispida, and S. samarangense caused, respectively, 34.1, 22.7, and 59.3% reductions in serum glucose levels when compared to control animals. The standard antihyperglycemic drug, glibenclamide, caused a 57.3% reduction in serum glucose levels versus control. Among the three plants evaluated, the methanolic extract of leaves of S. samarangense proved to be the most potent in demonstrating antihyperglycemic effects. The result validates the folk medicinal uses of A. carambola and F. hispida in the treatment of diabetes, and indicates that the leaves of S. samarangense can also possibly be used for amelioration of diabetes-induced hyperglycemia. 相似文献
22.
Hedwig E. Gockel Robert P. Carlyon Anahita Mehta Christopher J. Plack 《Journal of the Association for Research in Otolaryngology》2011,12(6):767-782
The frequency following response (FFR), a scalp-recorded measure of phase-locked brainstem activity, is often assumed to reflect
the pitch of sounds as perceived by humans. In two experiments, we investigated the characteristics of the FFR evoked by complex
tones. FFR waveforms to alternating-polarity stimuli were averaged for each polarity and added, to enhance envelope, or subtracted,
to enhance temporal fine structure information. In experiment 1, frequency-shifted complex tones, with all harmonics shifted
by the same amount in Hertz, were presented diotically. Only the autocorrelation functions (ACFs) of the subtraction-FFR waveforms
showed a peak at a delay shifted in the direction of the expected pitch shifts. This expected pitch shift was also present
in the ACFs of the output of an auditory nerve model. In experiment 2, the components of a harmonic complex with harmonic
numbers 2, 3, and 4 were presented either to the same ear (“mono”) or the third harmonic was presented contralaterally to
the ear receiving the even harmonics (“dichotic”). In the latter case, a pitch corresponding to the missing fundamental was
still perceived. Monaural control conditions presenting only the even harmonics (“2 + 4”) or only the third harmonic (“3”)
were also tested. Both the subtraction and the addition waveforms showed that (1) the FFR magnitude spectra for “dichotic”
were similar to the sum of the spectra for the two monaural control conditions and lacked peaks at the fundamental frequency
and other distortion products visible for “mono” and (2) ACFs for “dichotic” were similar to those for “2 + 4” and dissimilar
to those for “mono.” The results indicate that the neural responses reflected in the FFR preserve monaural temporal information
that may be important for pitch, but provide no evidence for any additional processing over and above that already present
in the auditory periphery, and do not directly represent the pitch of dichotic stimuli. 相似文献
23.
Anahita Jablonski-Momeni David N. J. Ricketts Stefanie Rolfsen Richard Stoll Monika Heinzel-Gutenbrunner Vitus Stachniss Klaus Pieper 《Lasers in medical science》2011,26(2):171-178
This study aimed to evaluate a laser fluorescence device (the DIAGNOdent) and a visual classification system (ICDAS-II) for
occlusal caries diagnosis. It also aimed to determine whether fluorescence measurements taken at the tooth surface correlate
with the fluorescence measurements taken within the body of the lesion. The occlusal surfaces of 100 extracted permanent teeth
were examined using ICDAS-II and DIAGNOdent (LF-tooth). Serial sections were made and lesion depth was assessed histologically.
DIAGNOdent readings were also taken from the sections (LF-section). There were significant positive strong correlations between
ICDAS-II and histology (rS = 0.71) and LF-section and histology (rS = 0.70), and only moderate correlations between LF-tooth and histology (rS = 0.51) and LF-tooth and LF-section (rS = 0.60). Diagnostic accuracy for ICDAS-II was generally better than for LF-tooth. While the DIAGNOdent device provides an
objective reading for detection and monitoring of carious lesions, using the cut-off ranges previously suggested leads to
inferior performance. 相似文献
24.
Antithrombin (ATIII), heparin cofactor II (HCII) and protein C inhibitor (PCI; also named plasminogen activator inhibitor-3) are serine protease inhibitors (serpins) whose thrombin inhibition activity is accelerated in the presence of glycosaminoglycans. We compared the inhibition properties of PCI and HCII to ATIII using R93A/R97A/R101A thrombin, an anion-binding exosite-2 (exosite-2) mutant that has greatly reduced heparin-binding properties. Heparin-enhanced PCI inhibition of R93A/R97A/R101A thrombin was only approximately 2-fold compared to 40-fold enhancement with wild-type recombinant thrombin. Thrombomodulin (TM) (with or without the chondroitin sulfate moiety) accelerated PCI inhibition of both wild-type and R93A/R97A/R101A thrombins. HCII achieved the same maximum activity in the presence of heparin with both wild-type and R93A/R97A/R101A thrombins; however, the optimum heparin concentration was 20 times greater than the reaction with wild-type thrombin, indicative of a decrease in heparin affinity. Dermatan sulfate (DSO4)-catalyzed HCII thrombin inhibition was unchanged in R93A/R97A/R101A thrombin compared to wild-type recombinant thrombin. These results suggest that PCI is similar to ATIII and depends upon ternary complex formation with heparin and these specific thrombin exosite-2 residues to accelerate thrombin inhibition. In contrast, HCII does not require Arg(93), Arg(97) and Arg(101) of thrombin exosite-2 and further supports the hypothesis that HCII uses an allosteric process following glycosaminoglycan binding to inhibit thrombin. 相似文献
25.
Expression of the beta-chemokine receptors CCR2, CCR3 and CCR5 in multiple sclerosis central nervous system tissue 总被引:11,自引:0,他引:11
Simpson J Rezaie P Newcombe J Cuzner ML Male D Woodroofe MN 《Journal of neuroimmunology》2000,108(1-2):192-200
Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system (CNS) characterised by perivascular inflammatory cell infiltrates and plaques of demyelination. Chemokines have been shown to play an important role in the activation and directional migration of cells to sites of CNS inflammation. The action of chemokines requires the expression of their complementary chemokine receptors by their target cells. We have examined the expression of the beta-chemokine receptors CCR2, CCR3 and CCR5 in post-mortem MS CNS tissue using single- and double-labelling immunocytochemistry techniques. Low levels of CCR2, CCR3 and CCR5 were expressed by microglial cells throughout control CNS tissue. In chronic active MS lesions CCR2, CCR3 and CCR5 were associated with foamy macrophages and activated microglia. CCR2 and CCR5 were also present on large numbers of infiltrating lymphocytes. A smaller number of CCR3-positive lymphocytes were present, but we also noted CCR3 and CCR5 on astrocytes in five of the 14 cases of MS investigated, particularly associated with processes around vessels and at the glia limitans. Ligands for CCR2 and CCR3 include MCP-1 and MCP-3 which were co-localised around vessels with the infiltrating leukocytes, but were also present in unaffected areas of cortex. The elevated expression of CCR2, CCR3 and CCR5 in the CNS in MS suggests these beta-chemokine receptors and their ligands play a role in the pathogenesis of MS. 相似文献
26.
Malekirad AA Ranjbar A Rahzani K Pilehvarian AA Rezaie A Zamani MJ Abdollahi M 《Environmental toxicology and pharmacology》2005,20(1):215-218
Excessive production of reactive oxygen species has been observed following acute and chronic exposure to radiation in animal models which can lead to several detrimental and irreversible outcomes in vital organs. Aim of this study was to determine the oxidative stress status in radiology unit workers which are exposed to persistent low-dose radiation. METHODS:: A group of 32 radiology unit employees along with 32 sex- and age-matched hospital workers, not exposed to low-dose radiation were recruited from two separate hospitals for the study. Exposed subjects showed higher levels of lipid peroxidation (P=0.009), total antioxidant capacity (P=0.0006) and thiol groups (P=0.03). It is concluded that occupationally exposed individuals are oxidatively stressed and precautions such as antioxidant therapy seems reasonable. 相似文献
27.
Muslims constitute a growing proportion of the African-American population. This paper explores the health practices, health behaviors, and code of ethics as informed by the Islamic religion within the context of African-American Muslim women's lives. An overview of the history of Islam in the world, and in the U.S., the main Islamic tenets, and the socio-cultural context of African-American Muslim women provides the broad framework for this paper. This information will be helpful in meeting the health needs of African-American Islamic women, within an outreach/community health promotion setting, within a clinical/hospital setting, or within a home care setting. 相似文献
28.
Rezaie AR 《Thrombosis and haemostasis》2003,89(1):112-121
Factor Xa (fXa) is the key enzyme of the prothrombinase complex that generates thrombin hence it is a good target for antithrombotic therapy. Here, the anti-fXa and anti-prothrombinase activities of DX-9065a which is an active-site directed inhibitor of fXa, and therapeutic heparins which are dependent on antithrombin (AT) for their anticoagulant function, were studied in amidolytic and proteolytic activity assays. It was found that DX-9065a is a competitive inhibitor of the Spectrozyme FXa (SpFXa) cleavage by both fXa and prothrombinase with similar K(i) values of approximately 10-20 nM. However, DX-9065a acted as a non-competitive inhibitor of prothrombin activation by prothrombinase with a Ki of approximately 26 nM. On the other hand, therapeutic heparins were effective catalysts of both fXa and prothrombinase inhibition by AT in the presence of SpFXa, but were ineffective in the presence of prothrombin. Further studies revealed that Tyr(99), a residue in the extended S2-S4 binding pocket of fXa, plays a key role in determination of specificity of the DX-9065a interaction. 相似文献
29.
30.
Psychotherapists' knowledge and understanding of Muslim women's culture is essential for them to effectively treat patients. Muslim women's culture is based on Islam, which permeates their thinking patterns, their interaction with themselves and others, and all activities of their daily lives. Western psychotherapy ineffectively treats Muslim women because its individualistic and fragmented method is contrary to the Muslim population's holistic spiritual approach to life. This article provides a theoretical integration of Eastern and Western therapeutic concepts for Muslim women, to promote a more effective therapeutic approach for this population residing in the United States. 相似文献