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排序方式: 共有124条查询结果,搜索用时 31 毫秒
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2.
Masoud Darvish Ganji Mahnaz Nashtahosseini Saeed Yeganegi Mahyar Rezvani 《Journal of molecular modeling》2013,19(4):1929-1936
The interaction between oxazepam and C60 fullerene was explored using first-principles vdW-DF calculations. It was found that oxazepam binds weakly to the fullerene cage via its carbonyl group. The binding of oxazepam to C60 is affected drastically by nonlocal dispersion interactions, while vdW forces affect the corresponding geometries only a little. Furthermore, aqueous solution affects the geometries of the oxazepam approaching to fullerene slightly, while oxazepam binds slightly farther away from the nanocage. The results presented provide evidence for the applicability of the vdW-DF method and serve as a practical benchmark for the investigation of host–guest interactions in biological systems. Figure
ab initio vdW-DF study on the possibility of formation of oxazepam/C60 complex at aqueous solution 相似文献
3.
Steven T. Bird Abraham G. Hartzema James M. Brophy Mahyar Etminan Joseph A.C. Delaney 《CMAJ》2013,185(2):E115-E120
Background:
There is an increased risk of venous thromboembolism among women taking oral contraceptives. However, whether there is an additional risk among women with polycystic ovary syndrome (PCOS) is unknown.Methods:
We developed a population-based cohort from the IMS LifeLink Health Plan Claims Database, which includes managed care organizations in the United States. Women aged 18–46 years taking combined oral contraceptives and who had a claim for PCOS (n = 43 506) were matched, based on a propensity score, to control women (n = 43 506) taking oral contraceptives. Venous thromboembolism was defined using administrative coding and use of anticoagulation. We used Cox proportional hazards models to assess the relative risk (RR) of venous thromboembolism among users of combined oral contraceptives with and without PCOS.Results:
The incidence of venous thromboembolism among women with PCOS was 23.7/10 000 person-years, while that for matched controls was 10.9/10 000 person-years. Women with PCOS taking combined oral contraceptives had an RR for venous thromboembolism of 2.14 (95% confidence interval [CI] 1.41–3.24) compared with other contraceptive users. The incidence of venous thromboembolism was 6.3/10 000 person-years among women with PCOS not taking oral contraceptives; the incidence was 4.1/10 000 person-years among matched controls. The RR of venous thromboembolism among women with PCOS not taking oral contraceptives was 1.55 (95% CI 1.10–2.19).Interpretation:
We found a 2-fold increased risk of venous thromboembolism among women with PCOS who were taking combined oral contraceptives and a 1.5-fold increased risk among women with PCOS not taking oral contraceptives. Physicians should consider the increased risk of venous thromboembolism when prescribing contraceptive therapy to women with PCOS.Polycystic ovary syndrome (PCOS) is the most common endocrine disorder among women of reproductive age. The National Institutes of Health criteria estimates its prevalence in the United States to be between 6% and 10%, while the Rotterdam criteria estimates the prevalence to be as high as 15%.1 Although its cause is not entirely known, the diagnostic criteria include oligo- or anovulation, clinical and/or biochemical signs of hyperandrogenism, and polycystic ovaries.2 Women often present with clinical manifestations of high androgen levels, including facial hair growth (hirsutism), acne vulgaris and hair loss on the scalp. Previous studies reported the prevalence of impaired glucose tolerance to be 31.1%–35.2% and the prevalence of type 2 diabetes to be 7.5%–9.8% among women with PCOS.3,4 A recent consensus workshop reported that the prevalence of several known risk factors for cardiovascular disease (hypertension, diabetes, abdominal obesity, psychological factors, smoking, altered apoA1/ApoB ratios) are doubled among women with PCOS compared with matched controls.1,5Combined oral contraceptives are the mainstay treatment for PCOS. However, they are also known to elevate the risk of venous thromboembolism and cardiovascular disease.6 To date, contraceptive studies involving women with PCOS have focused mainly on efficacy, evaluating the effect of combined oral contraceptives on the reduction of hirsutism and hyperandrogenism.7,8 Two studies assessed the metabolic effects of combined oral contraceptives in PCOS, but these studies had small sample sizes and could not evaluate for cardiovascular events.9,10Although women with PCOS have an increase in both cardiovascular risk factors and subclinical cardiovascular disease,11 recent guidelines have concluded there are no data in the literature assessing the association between the use of oral contraceptives and cardiovascular disease among women with PCOS.2 Because combined oral contraceptives are the mainstay treatment, our objective was to determine whether women with PCOS taking combined oral contraceptives have a greater risk of venous thromboembolism compared with other contraceptive users. We also examined whether women with PCOS not taking oral contraceptives had an increased risk of venous thromboembolism compared with the general population. 相似文献4.
Mahmood Amiri Narges Hosseinmardi Fariba Bahrami Mahyar Janahmadi 《Journal of computational neuroscience》2013,34(3):489-504
Neural synchronization is considered as an important mechanism for information processing. In addition, based on recent neurophysiologic findings, it is believed that astrocytes regulate the synaptic transmission of neuronal networks. Therefore, the present study focused on determining the functional contribution of astrocytes in neuronal synchrony using both computer simulations and extracellular field potential recordings. For computer simulations, as a first step, a minimal network model is constructed by connecting two Morris-Lecar neuronal models. In this minimal model, astrocyte-neuron interactions are considered in a functional-based procedure. Next, the minimal network is extended and a biologically plausible neuronal population model is developed which considers functional outcome of astrocyte-neuron interactions too. The employed structure is based on the physiological and anatomical network properties of the hippocampal CA1 area. Utilizing these two different levels of modeling, it is demonstrated that astrocytes are able to change the threshold value of transition from synchronous to asynchronous behavior among neurons. In this way, variations in the interaction between astrocytes and neurons lead to the emergence of synchronous/asynchronous patterns in neural responses. Furthermore, population spikes are recorded from CA1 pyramidal neurons in rat hippocampal slices to validate the modeling results. It demonstrates that astrocytes play a primary role in neuronal firing synchronicity and synaptic coordination. These results may offer a new insight into understanding the mechanism by which astrocytes contribute to stabilizing neural activities. 相似文献
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Transfer of PR1-specific T-cell clones from donor to recipient by stem cell transplantation and association with GvL activity 总被引:1,自引:0,他引:1
Rezvani K Price DA Brenchley JM Kilical Y Gostick E Sconocchia G Hansmann K Kurlander R Douek DC Barrett AJ 《Cytotherapy》2007,9(3):245-251
BACKGROUND: The curative effects of GvL following transfer of donor-derived T cells during allogeneic stem cell transplantation (SCT) are well established. However, little is known about the nature, origin and kinetics of the anti-leukemic T-cell responses involved. METHODS: We used quantitative real-time PCR (qRT-PCR) for interferongamma mRNA production (IFN-gamma) and PR1/HLA-A*0201 tetramer staining to detect PR1-specific CD8+ T-cell activity in a donor and a patient with CML. Unbiased strand switch anchored RT-PCR was used to further characterize specific clones in PR1 sorted CD8+ T-cell populations. RESULTS: We identified PR1-specific CD8(+) T-cell clones from a donor pre-transplant, and demonstrated their transfer in the recipient's blood post-SCT using molecular tracking of Ag-specific T-cell receptors. PR1-specific CD8(+) T-cell populations were polyclonal, with a range of functional avidities for cognate Ag, and displayed predominantly effector memory phenotype early post-SCT, suggesting active stimulation in vivo. Expansion of these PR1-specific CD8(+) T-cell clones in the recipient was followed by complete remission of CML. DISCUSSION: This report represents the first direct demonstration that PR1-specific CD8(+) T-cell clones can be transferred during SCT, and supports the feasibility of pre-transplant vaccination strategies that aim to boost the number of anti-leukemic T cells in the graft. 相似文献
8.
Mohammadi RS Samih MA Rezvani A Talebi AA 《Communications in agricultural and applied biological sciences》2007,72(3):475-485
Wrinkling aphid of pistachio leaf, Forda hirsuta Mordv. (Hem.:Pemphigidae) is one of the pests of pistachio trees. This aphid caused the shrinkage, thickening, and changing the color of the pistachio leaves. Since insect feeds from leave edges, the thick and rolled upward wrinkles were formed, which its green color turned into red. Therefore, its economical damages are out of direct feeding from plant extraction, twisting pistachio leaves, and the decrease of photosynthesis. In this research two orchards and 10 trees that each of them were selected in Rafsanjan region and 58 fundatrix galls, 120 nymphal galls were marked and the demographic parameters for apterus parthenogenesis female of this aphid were calculated via daily observations. The results indicated that intrinsic rates of increase (r) for 1, 2 and 3 generations were 0.01, 0.0638 and 0.0575 femal/femal/days respectively, Doubling time (DT) were 69.31, 10.52 and 12.04 days, respectively, net fecundity rates were 1.71, 11.5 and 7.37 femal/femal/days, respectively, Net fertility rates were 1.11, 8.87 and 5.01 days, respectively, and mean generation times (Tc) were calculated to be 31.5, 32.2 and 31.87 days, respectively. Other reproductive parameters such as gross hatch rate, gross fecundity rate, gross fertility rate, mean age gross fecundity and fertility, mean age net fecundity and fertility, mean age hatch, finite rate of increase (lambda), intrinsic birth rate (b) intrinsic death rate (d) and daily reproductive rate were also calculated. The results revealed that population parameters especially r in the first and second generations were lowest and highest, respectively and mean longevity of fundatrix was 30 days and the born nymphs made separate galls in the edge of pistachio leaves. 相似文献
9.
H. A. Abdolhay S. K. Daud S. Rezvani Ghilkolahi M. Pourkazemi S. S. Siraj M. K. Abdul Satar 《Reviews in Fish Biology and Fisheries》2011,21(2):247-257
Rutilus frisii kutum (Kamensky 1901) is one of the economically important fishes that migrate for spawning to rivers in the Caspian Sea. However,
the fish populations have slowly decreased in recent years. The declining of these resources has resulted from some activities
by the Iranian Fisheries Organization (IFO is responsible for stock enhancement) to catch some broodstocks of Rutilus frisii kutum from their natural spawning rivers. The broodstocks are caught for artificial propagation of the fish. Artificial propagations
are carried out every year to produce fingerlings to be released into the rivers in the Caspian Sea. In recent years, total
catch of this fish have greatly fluctuated due to the disruption of the natural spawning grounds and over fishing. The substantial
reduction to 1,298 metric tons, the lowest total catch reported in 1984–1985, could be due to over-exploitation of the fishery
resources. However, the total catch has increased after the fingerlings release programs started in 1979. The total numbers
of Rutilus frisii kutum fingerlings released had increased from 12 million to 225 million in 2002, to 155 million pieces in 2003, to 179 million
pieces in 2004, 229 million pieces in 2005, 174 million pieces in 2006, 262 million pieces in 2007 and 187.1 in 2008. The
total catch was also increased from 6,417 metric ton to 8,984 metric ton, to 7,036 metric ton, to 9,631 metric ton and 16,117,
17,196, 14,835 in years 2002, 2003, 2004, 2005, 2006, 2007 and 2008, respectively. 相似文献
10.