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排序方式: 共有5622条查询结果,搜索用时 15 毫秒
41.
Erin D. Wright Pota Christodoulopoulos Peter Small Saul Frenkiel Qutayba Hamid 《The Laryngoscope》1998,108(10):1528-1533
Objectives: Th-2 type cytokine production (inter-leukin-4 [IL-4] and interleukin-5 [IL-5]) has been demonstrated to play a significant role in the pathophysiology of allergic rhinitis (AR), and the treatment of AR with topical corticosteroids has been shown to reduce the expression of Th-2 type cytokines in vivo. However, the contribution and expression of Th-2 type cytokine receptors in AR and their response to corticosteroid treatment remain to be clarified. Objectives of the current study are 1. To examine the expression of the cytokine IL-4 and IL-5 receptors (IL-4R and IL-5R) in a nasal allergen challenge model and to contrast this with the expression of the receptor for the Th-1 type cytokine, interferon-gamma receptor (IFN-γR), and 2. to examine the effects of pretreatment with topical corticosteroid before allergen challenge on the expression of these same receptors. Study Design: Randomized prospective study involving 14 ragweed-allergic subjects evenly divided between placebo and corticosteroid pretreatment. Methods: Immunocytochemistry (alkaline phosphatase-antial-kaline phosphatase labeling [APAAP] technique) was used to stain nasal biopsy specimens before and after allergen challenge. Antibodies used included anti-CD3, CD4, CD8, MBP, IL-4R, IL-5R, and IFN-γR. Results: Following allergen challenge, we observed a significant increase in the Th-2 type cytokine receptors (IL-4R and IL-5R; P < .05), as well as a significant decrease in the expression of the Th-1 type cytokine receptor (IFN-γR; P < .05). Pretreatment with topical corticosteroids before nasal allergen challenge resulted in decreased expression of IL-4R (P < .05) and IL-5R (P < .05) and increased expression of IFN-γR (P < .05). Further, IL-4R and IL-5R expression correlated with eosinophil infiltration in the tissues. Conclusions: We have demonstrated that in AR, cytokine receptors for IL-4, IL-5, and IFN-γ follow a similar pattern to their ligands. In addition, pretreatment with topical corticosteroids was shown to alter the cytokine receptor expression pattern from a Th-2 profile more toward a Th-1 profile. Laryngoscope, 108:1528–1533,1998 相似文献
42.
Fatemeh Eghbalian Lotfollah Karimi Roya Raeisi Ayda Hasanpour Dehkordi Hamid Bouraghi 《Osong Public Health and Research Perspectives》2022,13(3):174
In neonates, bilirubin tends to be deposited in body tissues, especially the skin and mucous membranes. Jaundice is an early symptom of bilirubin excretion disorders. Therefore, the aim of this study was to investigate the effect of clofibrate on reducing neonatal jaundice. In this systematic review, international databases, including PubMed, Scopus, Web of Science, Embase, Cochrane, and Google Scholar, were searched without time and language restrictions. The reference lists of all studies ultimately included were manually searched. In the 17 articles reviewed, with a sample size of 665 people published between 2005 and 2019, the average weight of the neonates varied from 2,186 g to 4,000 g. Furthermore, the average age of neonates varied from 2 days to 9 days. Four doses of clofibrate (25, 30, 50, 100 mg/kg of neonatal body weight) were used. The bilirubin level of neonates significantly decreased in the intervention group 24, 36, 48, and 72 hours after the start of treatment. Clofibrate administration decreased total serum bilirubin, especially from the second day onwards, and also reduced hospitalization time, hospital costs, and side effects from hospitalization. 相似文献
43.
Harat ZN Sadeghi MR Sadeghipour HR Kamalinejad M Eshraghian MR 《Journal of ethnopharmacology》2008,115(1):36-41
AIM OF THE STUDY: Contraceptive plants which were introduced by folk in traditional remedies are investigated worldwide. In this study, the contraceptive effects of Ruta graveolens L., which has been mentioned for male contraceptive in Iranian traditional folk medicine, was experimented on human sperm. MATERIALS AND METHODS: Different doses of lyophilized aqueous extract of Ruta graveolens L. were added to an amount of fresh semen, containing 10(6) cells in a 1:1 volumic ratio. Motility and viability of cells, DNA status, mitochondrial activity and sperm revival tests were carried out. RESULTS: The sperm immobilization effects of the extract appeared immediately in a does-dependent manner and 100% of the sperms became immotile at a concentration of 100mg/ml but other parameters were intact. After washing the sperms, motility was returned in 30.8+/-3.2% of the sperms, besides coiled tails in 38.6+/-5.5% of the treated cells, in comparison to 12.5+/-2.0% of the control group (p=0.001). The part of the extract, responsible for immobilization of the sperms was stable upon boiling. CONCLUSIONS: As the cells were alive and immotile, probably some ionic currents are blocked by a thermostable component of the plant which can be promising as a new male channel blocker contraceptive. 相似文献
44.
In the present work, we provide a comprehensive numerical investigation of the magnetic properties and phase spectra of three types of spin-1/2 branched chains consisting of one, two and three side spins per unit block with intra-chain interaction and a uniform inter-chain interaction in the presence of an external magnetic field. In a specific magnetic field interval, the low-temperature magnetization of these chains shows a step-like behavior with a pronounced plateau depending on the strength and the type of intra-chain interaction being ferromagnetic or antiferromagnetic. We demonstrate that when inter-chain interaction is antiferromagnetic and intra-chain interaction is ferromagnetic, the magnetization of the models manifests a smooth increase without a plateau, which is evidence of the existence of a Luttinger-like spin liquid phase before reaching its saturation value. On the other hand, when is ferromagnetic and is antiferromagnetic, the low-temperature magnetization of the chain with two branches shows an intermediate plateau at one-half of the saturation magnetization that breaks a quantum spin liquid phase into two regions. The magnetization of the chain with three branches exhibits two intermediate plateaus and two regions of a quantum spin liquid. We demonstrate that the chains with more than one side spin illustrate in their ground-state phase diagram a Kosterlitz–Thouless transition from a gapful phase to a gapless spin liquid phase. 相似文献
45.
Jing Ying Lim Roslee Rajikan Noh Amit Nazlena Mohamad Ali Haslina Abdul Hamid Huey Yin Leong Maslina Mohamad Bi Qi Koh Aini Musa 《Nutrients》2022,14(12)
Dietary intervention is generally accepted as the mainstay of treatment for patients with disorders of amino acid metabolism (AAMDs). However, dietary adherence to a low-protein diet is always reported as a common challenge among these patients. This study explored the perception of barriers and motivators to dietary adherence among caregivers of AAMD patients in Malaysia. Twenty caregivers of children with AAMDs receiving ongoing treatment at the genetic clinic participated in an online focus group discussion from November to December 2021. Findings showed a total of five interrelated main themes identified from focus group discussion (FGD) exploring parents’ experiences related to the management of their child’s daily diet. The barriers to dietary adherence were burden of dietary treatment, diet and dietary behavior, parenting challenges, limited knowledge related to dietary treatment, and challenges in healthcare system delivery. Key factors facilitating good dietary adherence include good knowledge of dietary treatment, parental coping strategies, social coping, and dietary behavior. In conclusion, despite the existence of several barriers to the implementation of dietary treatment, caregivers managed to use a wide range of coping strategies to overcome some, if not all, of the challenges. The important next step is to develop, in conjunction with multidisciplinary healthcare professionals, feasible implementation strategies that could address these barriers and at the same time improve the quality of life of caregivers. 相似文献
46.
Moyamoya disease is an unusual occlusive cerebrovascular condition commonly seen in children, marked by stenosis of the internal carotid artery and circle of Willis, causing, cerebral ischemia. Moyamoya syndrome is a Moyamoya-like arteriopathy with risk factors including autoimmune disorders, thyroid disease, sickle cell disease, or Down syndrome. Trisomy 21 is a genetic disorder consistent with specific physical and behavioral characteristics, with intellectual impairment. We describe a rare case of Moyamoya syndrome manifesting as ischemic stroke in an adult with Down syndrome 相似文献
47.
Benjamin R.Troutwine Laylan Hamid Colton R.Lysaker Taylor A.Strope Heather M.Wilkins 《药学学报(英文版)》2022,12(2):496-510
Genetic variation in apolipoprotein E (APOE) influences Alzheimer's disease (AD) risk. APOE ε4 alleles are the strongest genetic risk factor for late onset sporadic AD. The AD risk is dose dependent, as those carrying one APOE ε4 allele have a 2–3-fold increased risk, while those carrying two ε4 alleles have a 10–15-fold increased risk. Individuals carrying APOE ε2 alleles have lower AD risk and those carrying APOE ε3 alleles have neutral risk. APOE is a lipoprotein which functions in lipid transport, metabolism, and inflammatory modulation. Isoform specific effects of APOE within the brain include alterations to Aβ, tau, neuroinflammation, and metabolism. Here we review the association of APOE with AD, the APOE isoform specific effects within brain and periphery, and potential therapeutics. 相似文献
48.
Nur Najihah Izzati Mat Rani Xiang Yi Chen Zahraa M.Al-Zubaidi Hanisah Azhari Tzar Mohd Nizam Khaitir Pei Yuen Ng Fhataheya Buang Geok Chin Tan Yin Ping Wong Mazlina Mohd Said Adeel Masood Butt Azmy A.Hamid Mohd Cairul Iqbal Mohd Amin 《Asian Journal of Pharmaceutical Sciences》2022,17(1):102-119
This study focused on the encapsulation of vancomycin(VAN) into liposomes coated with a red blood cell membrane with a targeting ligand, daptomycin–polyethylene glycol–1,2-distearoyl-sn-glycero-3-phosphoethanolamine, formed by conjugation of DAPT and Nhydroxysuccinimidyl-polyethylene glycol-1,2-distearoyl-sn-glycero-3-phosphoethanolamine.This formulation is capable of providing controlled and targeted drug delivery to the bacterial cytoplasm. We performed MALDI-TOF, NMR and FTIR analyses to conf... 相似文献
49.
Snake modeling and distance transform approach to vascular centerline extraction and quantification 总被引:4,自引:0,他引:4
A new method for fully automated centerline extraction and quantification of microvascular structures in confocal microscopy (CM) images is presented. Our method uses the idea of active contour models as well as path planning and distance transforms for the three-dimensional centerline extraction of elongated objects such as vessels. The proposed approach is especially efficient for centerline extraction of complex branching structures. The method performance is validated in several CM images of both normal and stroked rat brains as well as simulated objects. The results confirm the efficiency of the proposed method in extracting the medial curve of vessels, which is essential for the computation of quantitative parameters. 相似文献
50.