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91.
A highly sensitive, simple and rapid spectrofluorimetric method was developed for the determination of azelastine HCl (AZL) in either its pure state or pharmaceutical dosage form. The proposed method was based on measuring the native fluorescence of the studied drug in 0.2 M H2SO4 at λem = 364 nm after excitation at λex = 275 nm. Different experimental parameters were studied and optimized carefully to obtain the highest fluorescence intensity. The proposed method showed a linear dependence of the fluorescence intensity on drug concentration over a concentration range of 10–250 ng/mL, with a limit of detection of 1.52 ng/mL and limit of quantitation of 4.61 ng/mL. Moreover, the method was successfully applied to pharmaceutical preparations, with percent recovery values (± SD) of 99.96 (± 0.4) and 100.1 (± 0.52) for nasal spray and eye drops, respectively. The results were in good agreement with those obtained by the comparison method, as revealed by Student's t‐test and the variance ratio F‐test. The method was extended to study the stability of AZL under stress conditions, where the drug was exposed to neutral, acidic, alkaline, oxidative and photolytic degradation according to International Conference on Harmonization (ICH) guidelines. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
92.
Capsule: Mediterranean Yellow-legged Gulls mate assortatively according to carotenoid-based colouration but not in relation to size.  相似文献   
93.
Capsule Crèches formed early in the season lasted longer than those formed later, but a longer crèching period did not appear to confer higher chick survival.

Aims To investigate the ecological factors influencing the benefit to parents of crèching behaviour by measuring chick survival.

Methods Mark–recapture was used to model apparent daily survival of 505 chicks during the crèching period in three different crèches. We contrasted models with different tipping points to assess possible differences across crèches in chick survival during the first week and in the moment at which chick departures began.

Results We did not find a clear difference across crèches on daily chick survival during the first stages of the crèche. By modelling chick apparent survival as a linear function of time we showed that the latest formed crèche dispersed more rapidly.

Conclusions The two crèches formed early in the season lasted longer than the one formed later but chicks did not appear to have a higher survival over the first week of crèching. We suggest that a longer period at the crèche should result in a higher survival in the period soon after fledging because chicks leave the crèche 4–7 days older than other chicks. Furthermore, early crèches are synchronous with those of other species breeding in the same area, thus perhaps diluting predation. We discuss the limitations of our analysis and the possible implications for the community of waterbirds breeding at our study site.  相似文献   
94.
Purification of DNA-dependent RNA polymerase from exponentially growing cells of the cyanobacteriumSynechococcus sp. is described in cultures grown at normal temperature (39°C) and after heat shock (HS) (47°C). Polyethyleneimine precipitation followed by chromatography and gel filtration steps results in a 39% yield. The enzyme has a component of molar mass of 43 kDa, designated σ, in addition to the typical procaryotic β’β∝2 and γ. The results suggest thatSynechococcus RNA polymerase is similar to that of cyanobacterial andE. coli RNA polymerases. Electrophoresis of the HS preparation showed that the enzyme has a component of 18 kDa. This suggests the existence of a functional relationship between this protein and the HS response ofSynechococcus RNA polymerase, probably in salvaging denatured RNA polymerase or helping to regain its native structure.  相似文献   
95.
This study focuses on the effect of ploughing on plant abundance,vegetation cover, species richness, and taxonomic diversity during the growingseasons (winter and spring) of 1992 and 2000 in the habitat of inland plateau(natural habitat), 21 km south of Mersa-Matrouh (Egypt).Ninety-five species belonging to 27 families were recorded. High percentages oflife-forms and a large number of species were recorded in ploughed andunploughed stripes in the winter and spring of 2000. Higher averages of importancevalues (IVs) and absolute frequencies were recorded for most perennial andannual species in the unploughed stripes compared to the ploughed ones. This may beattributed to crop failure and consequently unfavourable soil conditions. On theother hand, some shrubby species (e.g. Noaea mucronata andHaloxylon scoparium) and perennial herbs (e.g.Gynandriris sisyrinchium) attained higher IVs in theploughed stripes compared to unploughed ones. This may be attributed to thecultivation of Prosopis juliflora trees in the elevatedpart of the ploughed stripes, which have an ecological role in protecting andenriching the soil with organic matter, thus favouring the growth of theseshrubs and perennial herbs. Higher species richness and diversity wereassociated with low concentration of dominance and low taxonomic diversity inthe spring of 2000 in ploughed and unploughed stripes compared to the winter of1992, for both perennials and annuals. The lowest taxonomic diversities wereexhibited in the spring of 2000 for ploughed and unploughed stripes where thevegetation had the largest number of congeneric species and confamilial genera.Higher species richness and diversity characterized the vegetation of theunploughed stripes, especially in winter and spring 2000, as compared to those ofploughed ones. The present study also reveals low species richness and diversityof therophytes in winter for both ploughed and unploughed stripes.  相似文献   
96.
Both the original Bethesda system and the current UK classifications of cervical cytology have proved robust but each has a major weakness in the area of abnormalities of uncertain significance. Cytologists recognize that sometimes it is simply impossible to differentiate between reactive and dyskaryotic material. For this reason, the Australian version of the Bethesda system introduced a new category of 'high grade inconclusive' with a recommendation for referral to colposcopy. Approximately 60% of such cases are found to have high grade lesions at colposcopy (Schoolland M, Sterrett G, Knowles S et al .). The present UK system even with the proposed changes requires of the pathologist, a decision as to whether such cases are probably high grade (=a report of moderate dyskaryosis) or not (= a report of borderline). This continues to ignore the fact that sometimes you just cannot tell, even on review. We have taken a consecutive series of 50 referral smears, reported as moderate dyskaryosis, where the histological outcome (by loop cone) is known. These cases were rescreened and then reviewed blind by a pathologist with extensive experience of the Australian NH & MRC modified Bethesda system. On review, the material was reclassified along NH & MRC lines. The results were compared with the biopsy findings in order to determine whether the category of 'inconclusive' might be of value in the context of the NHSCSP.  相似文献   
97.
The cyanobacteriumSynechocystis PCC 6803 was grown photoautotrophically in an inorganic medium at constant growth temperatures of 20, 38 (control) or 43°C for 9 h. The up and down-shift of cultivation temperature decreased the growth as measured by culture absorbance and chlorophylla content. However, high temperature slightly increased the oxygen evolution while temperature lower than control inhibited oxygen evolution during the whole incubation period. The protein synthesis studied by14C-labeled protein declined under low temperature by about 50%. The fatty acid pattern is characterized as lacking in C20/C22 acids but containing large amounts of C16 and C18 polyunsaturated fatty acids, 16:2 and 18:3 in particular. The lower temperature increased the percentage of monounsaturated fatty acids while higher temperature increased the saturated fatty acid content in total lipids and lipid classes studied.  相似文献   
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The present study aimed to investigate the effect of walnut consumption on lipid profile, steroid hormones and inflammation in trained elderly men performing concurrent (resistance and endurance) training. Twenty healthy elderly males were divided into two matched groups, in a randomized controlled trial, that trained three sessions per week: concurrent training + dietary walnut consumption (15 g/day for six weeks, CTW: n = 10); concurrent training + control diet (CT: n = 10). Fasting blood samples were taken 48 hours before and after intervention for biochemical assessments. levels of high-density lipoprotein (HDL) increased only in CTW compared to baseline (19.8%, p < 0.01). Total cholesterol (TC), low-density lipoprotein (LDL) and triglyceride (TG) levels significantly decreased only for CTW (i.e., 13%, 18%, and 18.5% at p < 0.01 for all). Testosterone (T) increased after the training compared to pre-training for CTW and CT (10.3%, p < 0.01, 4.27% p < 0.05, respectively), but the increase was significantly higher in CTW (p < 0.05). Serum cortisol (C) was lower for CTW compared to CT (p < 0.01). C-reactive protein (CRP) decreased in CTW in comparison with CT. The present study revealed that 6-week moderate walnut supplementation (15 g/day) improved lipid profile, steroid hormones and systematic inflammation in aged men performing concurrent training. These findings could be attributable to the potential effect of polyunsaturated fatty acids (PUFA) contained in walnut (linoleic acid, n-6; linolenic acid, n-3).  相似文献   
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