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691.
692.
Background
Empirical binding models have previously been investigated for the energetics of protein complexation (ΔG models) and for the influence of mutations on complexation (i.e. differences between wild-type and mutant complexes, ΔΔG models). We construct binding models to directly compare these processes, which have generally been studied separately. 相似文献693.
694.
Summary The effects of several factors on the rate and the capacity of lead adsorption by river-mud were studies. These factors included the concentration of mud, the concentration of lead, the organic matter content of mud, pH, time of adsorption, temperature and agitation. The reaction order of the adsorption process with respect to lead and the type of adsorption were determined. Also, indications of the rate-limiting step were discussed and an empirical equation describing the adsorption of lead on river-mud was developed. 相似文献
695.
Ibrahim M. Gosadi Khaled A. Daghriri Abdullah A. Otayf Abdulrhman A. Nemri Abdulaziz A. Kaal Abdullah M. Qussadi Manal M. Maashi Alshaymaa M. Arishy Hadeel M. Mushafa Abdulrhman M. Salim 《Saudi Journal of Biological Sciences》2021,28(5):2951-2955
BackgroundPatient’s awareness of their clinical and laboratory parameters is an indicator of the degree of involvement in achieving their management goals. This investigation aimed to identify awareness of patients affected by chronic non-communicable diseases of their clinical and laboratory parameters and factors associated with the awareness.MethodsThis study was a cross-sectional investigation conducted in the Jazan region, between January and August 2020. Data was collected during phone interviews utilizing a semi-structured questionnaire. Odds ratios (ORs) were calculated to estimate the likelihood of awareness of each clinical and laboratory parameter according to the measured demographic variables.ResultsThe total number of recruited patients was 675. The mean age of participants was 53.7 years and the 28.7% of patients were illiterate. About 17% of the patient do not attend follow-up visits to any healthcare provider. When patients were asked about their parameters, 87% of them were able to report their body weight and 74% were able to report their height. However, less than half of patients were aware of their glycated hemoglobin level (HbA1c) (271/675 patients) and systolic blood pressure (BP) level (329/ 675 patients), and a minority were aware of their total cholesterol level (71/675 patients). Being female, resident in a rural area, illiterate, and older than 53 was strongly associated with high odds of limited awareness about their own clinical and laboratory parameters (P values < 0.05).ConclusionAwareness of patients affected by chronic non-communicable diseases of their own clinical and laboratory parameters in the Jazan region is sub-optimal where this limited awareness is likely to be associated with the lower engagement of patients with achieving their desired management targets. 相似文献
696.
Salim Zerrouk Olga Escuredo María Shantal Rodríguez-Flores María Carmen Seijo 《Grana》2021,60(1):69-80
Abstract A melissopalynological study was carried out on 46 samples of Ziziphus lotus honey from Laghouat and Djelfa region (central Algeria). The number of pollen types identified per honey sample ranges between nine and 39 with a mean of 24. These correspond to 52 botanical families with 79 different pollen types in the whole samples. Asteraceae and Fabaceae families were present in all the samples where as Apiaceae, Brassicaceae and Nitrariaceae (Peganum harmala) were identified in more than 90%. Other plant families as Boraginaceae, Cistaceae, Myrtaceae, Oleaceae, Salicaceae or Urticaceae were identified in more than 50% of the samples but frequently as minor pollen. Ziziphus lotus pollen had a mean content of 68.9% (with a range of 45.3% to 93.4%). The secondary pollen types were Ononis natrix, Peganum harmala, Brassica napus, Echium and Olea europaea. Regarding the important pollen it is highlighted the presence Lotus t., Eucalyptus, Pimpinella anisum t., Trifolium t., Eryngium campestre t., Centaurea t., Galega officinalis t., Citrus or Scrophularia t. The sedra honeys of the studied region are characterised by their high content in pollen grains with a mean content of 188 403 grains/10 g. The presence of some pollen types in the pollen spectra of honeys such as Peganum harmala, Thapsia garganica, Launaea, Muscari comosum, Carthamus or Limonium bonduellei together several Asteraceae as Centaurea, Taraxacum, Carduus, Artemisia and Matricaria was proposed as geographical markers of this honey type. 相似文献
697.
Ibtisam Salim Eleonora Staines-Urias Sam Mathewlynn Lior Drukker Manu Vatish Lawrence Impey 《PLoS medicine》2021,18(1)
BackgroundBreech presentation at term contributes significantly to cesarean section (CS) rates worldwide. External cephalic version (ECV) is a safe procedure that reduces term breech presentation and associated CS. A principal barrier to ECV is failure to diagnose breech presentation. Failure to diagnose breech presentation also leads to emergency CS or unplanned vaginal breech birth. Recent evidence suggests that undiagnosed breech might be eliminated using a third trimester scan. Our aim was to evaluate the impact of introducing a routine 36-week scan on the incidence of breech presentation and of undiagnosed breech presentation.Methods and findingsWe carried out a population-based cohort study of pregnant women in a single unit covering Oxfordshire, United Kingdom. All women delivering between 37+0 and 42+6 weeks gestational age, with a singleton, nonanomalous fetus over a 4-year period (01 October 2014 to 30 September 2018) were included. The mean maternal age was 31 years, mean BMI 26, 44% were nulliparous, and 21% were of non-white ethnicity. Comparisons between the 2 years before and after introduction of routine 36-week scan were made for 2 primary outcomes of (1) the incidence of breech presentation and (2) undiagnosed breech presentation. Secondary outcomes related to ECV, mode of birth, and perinatal outcomes. Relative risks (RRs) with 95% confidence intervals (CIs) are reported. A total of 27,825 pregnancies were analysed (14,444 before and 13,381 after). A scan after 35+0 weeks was performed in 5,578 (38.6%) before, and 13,251 (99.0%) after (p < 0.001). The incidence of breech presentation at birth did not change significantly (2.6% and 2.7%) (RR 1.02; 95% CI 0.89, 1.18; p = 0.76). The rate of undiagnosed breech before labour reduced, from 22.3% to 4.7% (RR 0.21; 95% CI 0.12, 0.36; p < 0.001). Vaginal breech birth rates fell from 10.3% to 5.3% (RR 0.51; 95% CI 0.30, 0.87; p = 0.01); nonsignificant increases in elective CS rates and decreases in emergency CS rates for breech babies were seen. Neonatal outcomes were not significantly altered. Study limitations include insufficient numbers to detect serious adverse outcomes, that we cannot exclude secular changes over time which may have influenced our results, and that these findings are most applicable where a comprehensive ECV service exists.ConclusionsIn this study, a universal 36-week scan policy was associated with a reduction in the incidence but not elimination of undiagnosed term breech presentation. There was no reduction in the incidence of breech presentation at birth, despite a comprehensive ECV service.Ibtisam Salim and co-workers report on incidence of breech presentation in pregnant women receiving a 36-week scan. 相似文献
698.
699.
Basilio A. Kotsias Mohammad Salim Lillian L. Peracchia Camillo Peracchia 《The Journal of membrane biology》2006,214(1-2):1-8
The cystic fibrosis transmembrane regulator (CFTR) is a Cl− channel known to influence other channels, including connexin (Cx) channels. To study the functional interaction between
CFTR and gap junction channels, we coexpressed in Xenopus oocytes CFTR and either Cx45, Cx40, Cx32 or Cx50 and monitored junctional conductance (G
j) and its sensitivity to transjunctional voltage (V
j) by the dual voltage-clamp method. Application of forskolin induced a Cl− current; increased G
j approximately 750%, 560%, 64% and 8% in Cx45, Cx40, Cx32 and Cx50, respectively; and decreased sensitivity to V
j gating, monitored by a change in the ratio between G
j steady state and G
j peak (G
jSS/G
jPK) at the pulse. In oocyte pairs expressing just Cx45 in one oocyte (#1) and both Cx45 and CFTR in the other (#2), with negative
pulses applied to oocyte #1 forskolin application still increased G
j and decreased the sensitivity to V
j gating, indicating that CFTR activation is effective even when it affects only one of the two hemichannels and that the G
j and V
j changes are not artifacts of decreased membrane resistance in the pulsed oocyte. COOH-terminus truncation reduced the forskolin
effect on Cx40 (Cx40TR) but not on Cx32 (Cx32TR) channels. The data suggest a cross-talk between CFTR and a variety of gap
junction channels. Cytoskeletal scaffolding proteins and/or other intermediate cytoplasmic proteins are likely to play a role
in CFTR-Cx interaction. 相似文献
700.
The Striga, particularly S. he rmonthica, problem has become a major threat to food security, exacerbating hunger and poverty in many African countries. A number of Striga control strategies have been proposed and tested during the past decade, however, further research efforts are still needed to provide sustainable and effective solutions to the Striga problem. In this paper, we provide an update on the recent progress and the approaches used in Striga management, and highlight emerging opportunities for developing new technologies to control this enigmatic parasite. Advances
- The recently established Striga control technologies, such as push-pull, toothpick, and imidazolinone seed dressing have opened up new opportunities for smallholder farmers to overcome this parasite.
- The development of low-cost and efficient germination stimulants together with an application protocol for rain-fed agriculture has made the suicidal germination strategy a realistic approach.
- Molecular elucidation of strigolactone biosynthesis and perception has led to the development of new chemicals that disrupt the communication between Striga and its hosts.