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排序方式: 共有412条查询结果,搜索用时 15 毫秒
121.
122.
Zia KM Zuber M Barikani M Hussain R Jamil T Anjum S 《International journal of biological macromolecules》2011,49(5):1131-1136
Chitin based polyurethane bio-nanocomposites (PUBNC) were prepared using chitin, Delite® HPS bentonite nanoclay enriched in montmorillonite (MMT), 4,4′-diphenylmethane diisocyanate (MDI) and polycaprolactone polyol CAPA 231 (3000 g/mol−1). The prepolymers having different concentration of Delite HPS bentonite nanoclay were extended with 2 moles of chitin. The structures of the resulted polymers were determined by FT-IR technique. The effect of nanoclay contents on mechanical properties and in vitro biocompatibility was investigated. The mechanical properties of the synthesized materials were improved with increase in the Delite HPS® bentonite nanoclay contents. Optimum mechanical properties were obtained from the PU bio-nanocomposite samples having 4% Delite HPS® bentonite nanoclay. The results revealed that the final PU bio-nanocomposite having 2% Delite HPS® bentonite nanoclay contents is ideal contenders for surgical threads with on going investigations into their in vitro biocompatibility, non-toxicity, and mechanical properties. 相似文献
123.
124.
Gene Expression Profiling of Plants under Salt Stress 总被引:1,自引:0,他引:1
125.
Amr S. Abou El-Ela Eldessoky S. Dessoky Saad Masry Aqsa Arshad Asim Munawar Samina Qamer Ahmed Abdelkhalek Said I. Behiry Ahmed Kordy 《Saudi Journal of Biological Sciences》2021,28(6):3351-3361
The wasp, Bracon hebetor Say, is an important potential biocontrol agent of a wide range of lepidopteran insect species. The current study was subjected to compare these ectoparasitoid fitness traits on different host species belonging to the order Lepidoptera. Moreover, we determine the population dynamic with different host densities, sex ratio patterns, super-parasitism, longevity, paralysis success, and reproductive potential under laboratory conditions. Our results revealed that oviposition increased with an increase in host density, while the adult emergence and egg hatching were decreased due to the super-parasitism on host larvae. A higher male and female-biased population were observed when virgin and mated females offered fresh hosts. Adults' longevity was recorded more in females than males when kept only with bee honey + royal jelly + host larvae. The mean duration of egg-adult development was recorded higher on Galleria mellonella and lowest on Busseola fusca. The parasitization rate, super-parasitism, and cumulative fecundity of mated and virgin female wasps with different host species were observed higher on specific host Galleria mellonella while it was lower on Phthorimaea operculella. Furthermore, the parasitoids having mating experience preferred fresh, while the parasitoids' lack of mating experiences preferred paralyzed host under olfactometer test. Besides, this research has produced novel facts on the biology of parasitic wasp, B. hebetor that may guide the advancement of sustainable biological control programs to control lepidopteran pests. 相似文献
126.
Curtis SL Zambanini A Mayet J McG Thom SA Foale R Parker KH Hughes AD 《American journal of physiology. Heart and circulatory physiology》2007,293(1):H557-H562
In human heart failure the role of wave generation by the ventricle and wave reflection by the vasculature is contentious. The aim of this study was to compare wave generation and reflection in normal subjects with patients with stable compensated heart failure. Twenty-nine normal subjects and 67 patients with heart failure (New York Heart Association class II or III) were studied by noninvasive techniques applied to the common carotid artery. Data were analyzed by wave intensity analysis to determine the nature and direction of waves during the cardiac cycle. The energy carried by an early systolic forward compression wave (S wave) generated by the left ventricle and responsible for acceleration of flow in systole was significantly reduced in subjects with heart failure (P < 0.001), and the timing of the peak of this wave was delayed. In contrast, reflection of this wave was increased in subjects with heart failure (P < 0.001), but the timing of reflections with respect to the S wave was unchanged. The energy of an expansion wave generated by the heart in protodiastole was unaffected by heart failure. The carotid artery wave speed and the augmentation index did not significantly differ between subjects with heart failure compared with normal individuals. The ability of the left ventricle to generate a forward compression wave is markedly impaired in heart failure. Increased wave reflection serves to maintain systolic blood pressure but also places an additional load on cardiac function in heart failure. 相似文献
127.
Ahmad Muhammad Zulfiqar Sana Aiman Jamil Arshad Nasir Jamal Abdul Ahmed Shakeel Hameed Muhammad Uzair Abdullah 《Plant molecular biology》2019,100(6):607-620
Plant Molecular Biology - A vital role of short amino acid gene family, gibberellic acid stimulated arabidopsis (GASA), has been reported in plant growth and development. Although, little... 相似文献
128.
Lily G. C. Genevier Tahira Jamil Dionysios E. Raitsos George Krokos Ibrahim Hoteit 《Global Change Biology》2019,25(7):2338-2351
As the Earth's temperature continues to rise, coral bleaching events become more frequent. Some of the most affected reef ecosystems are located in poorly monitored waters, and thus, the extent of the damage is unknown. We propose the use of marine heatwaves (MHWs) as a new approach for detecting coral reef zones susceptible to bleaching, using the Red Sea as a model system. Red Sea corals are exceptionally heat‐resistant, yet bleaching events have increased in frequency. By applying a strict definition of MHWs on >30 year satellite‐derived sea surface temperature observations (1985–2015), we provide an atlas of MHW hotspots over the Red Sea coral reef zones, which includes all MHWs that caused major coral bleaching. We found that: (a) if tuned to a specific set of conditions, MHWs identify all areas where coral bleaching has previously been reported; (b) those conditions extended farther and occurred more often than bleaching was reported; and (c) an emergent pattern of extreme warming events is evident in the northern Red Sea (since 1998), a region until now thought to be a thermal refuge for corals. We argue that bleaching in the Red Sea may be vastly underrepresented. Additionally, although northern Red Sea corals exhibit remarkably high thermal resistance, the rapidly rising incidence of MHWs of high intensity indicates this region may not remain a thermal refuge much longer. As our regionally tuned MHW algorithm was capable of isolating all extreme warming events that have led to documented coral bleaching in the Red Sea, we propose that this approach could be used to reveal bleaching‐prone regions in other data‐limited tropical regions. It may thus prove a highly valuable tool for policymakers to optimize the sustainable management of coastal economic zones. 相似文献
129.
Mohammad Bagher Erfanian Hamid Ejtehadi Jamil Vaezi Hamid Moazzeni Farshid Memariani Mohammad Firouz‐Jahantigh 《Ecology and evolution》2019,9(14):8193-8200
It is well‐known that pistes have adverse effects on alpine ecosystems. Previous studies urged that pistes should be installed and managed in the ways to minimize negative impacts on natural habitats. However, the impacts of this type of management on the plant communities are not widely studied. The aim of this study was to examine species composition and biodiversity changes in an environmentally friendly managed piste in northeast Iran. This piste has been established in a previously degraded alpine landscape. For the vegetation survey, we sampled 44 within and 28 off‐piste plots. Except for the piste management, other environmental factors were similar between the piste and off‐piste plots. Dominant species were determined, and variation in community composition of the two areas was visualized. Also, native species, phylogenetic, and functional Hill diversity of the two areas were compared. The results showed that there was a moderate differentiation in the species composition of the piste and off‐piste. Two palatable species (i.e., Bupleurum falcatum and Melica persica) were dominant in the piste and were not recorded in the off‐piste. The diversity calculations results showed that the species diversity of the piste was higher than that of the off‐piste. Phylogenetic diversity at the level of frequent and dominant plants showed a similar result. The piste had a higher functional diversity in terms of functional richness, and functional diversity of frequent and dominant plants. Our findings imply, after 10 years, species, phylogenetic, and functional diversity of the piste is significantly improved. Environmentally friendly piste management (EFPM) induced species composition change that led to emerging species that were absent in the off‐piste. We can conclude that EFPM led to restoration of a degraded landscape. Long‐term impacts of EFPM are still unknown, therefore, caution should be undertaken regarding the installation of new environmentally friendly pistes in other areas. 相似文献
130.
Hussain R Daud S Kakar N Ahmad A Baloch AH Tareen AM Kakar MA Ahmad J 《Molecular biology reports》2012,39(5):6197-6201
Canavan disease (OMIM 271900) is an autosomal recessive lethal neurodegenerative disorder characterized by spongy degeneration
of the brain. A highly consanguineous Pakistani family with Canavan disease was enrolled on the basis of diagnosis. All the
affected individuals have mental retardation, megalocephaly and degradation of motor skills, poor head control, partial vision
loss, weakness of the muscles and raised urinary concentration of N-acetyl aspartic acid in the urine. Blood samples were
collected from affected as well as normal siblings and processed for DNA purification. Linkage analysis was performed by typing
three short tandem repeat markers D17S1583 (7.19 cM), D17S1828 (10.02 cM) and D17S919 (14.69 cM) for an already-reported gene/locus
ASPA at chromosome 17p13.2 causing Canavan disease. During linkage analysis, all the affected individuals were homozygous for
short tandem repeat markers while the normal siblings were heterozygous showing co-segregation of the disease. Gene ASPA (NM_000049) was undertaken to sequence for mutation analysis. As a result of sequence analysis, we found missense substitution
740A→G (p.G274R) in exon 6 of gene ASPA. To our knowledge, this is the first report about Canavan disease on a Pakistani family. 相似文献