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61.
Mycorrhizal plants often have greater tolerance to drought than nonmycorrhizal plants. This study was conducted to determine the effects of arbuscular mycorrhizal (AM) fungi inoculation on growth, grain yield and mineral acquisition of two winter wheat (Triticum aestivum L.) cultivars grown in the field under well-watered and water-stressed conditions. Wheat seeds were planted in furrows after treatment with or without the AM fungi Glomus mosseae or G. etunicatum. Roots were sampled at four growth stages (leaf, tillering, heading and grain-filling) to quantify AM fungi. There was negligible AM fungi colonization during winter months following seeding (leaf sampling in February), when soil temperature was low. During the spring, AM fungi colonization increased gradually. Mycorrhizal colonization was higher in well-watered plants colonized with AM fungi isolates than water-stressed plants. Plants inoculated with G. etunicatum generally had higher colonization than plants colonized with G. mosseae under both soil moisture conditions. Biomass and grain yields were higher in mycorrhizal than nonmycorrhizal plots irrespective of soil moisture, and G. etunicatum inoculated plants generally had higher biomass and grain yields than those colonized by G. mosseae under either soil moisture condition. The mycorrhizal plants had higher shoot P and Fe concentrations than nonmycorrhizal plants at all samplings regardless of soil moisture conditions. The improved growth, yield and nutrient uptake in wheat plants reported here demonstrate the potential of mycorrhizal inoculation to reduce the effects of drought stress on wheat grown under field conditions in semiarid areas of the world. 相似文献
62.
Ghazi P 《BMJ (Clinical research ed.)》2000,321(7273):1367
63.
H. A. Ghazi 《BMJ (Clinical research ed.)》1972,1(5793):144-145
In a study of 99 patients with pernicious anaemia the incidence of clinical rheumatoid arthritis was normal but rheumatoid factor was present significantly more often than in controls. This was not related to the presence of circulating antibody to intrinsic factor.Intrinsic factor antibody was not detected in any of 151 latex-fixation-positive rheumatoid sera. 相似文献
64.
Bougrid A Claudepierre T Picaud S Ayad G Mornet D Dorbani-Mamine L Rendon A Darbeida H 《Neurochemical research》2011,36(8):1407-1416
The dystrophin-associated-protein complex (DAPC) has been extensively characterized in the central nervous system where it
is localized both in neuronal and glial cells. Few studies have characterized this complex in the neurohypophysis. To further
study this complex in pituicytes, the resident astroglia of the neurophypophysis, we used adult pituicyte cultures and determined
the expression and localization of dystrophins/utrophins and the DAPC by RT–PCR, western blotting and immunofluorescence.
Our data show that the pituicytes express dystrophins, utrophins and several members of the DAPC including dystroglycans,
δ-, γ-sarcoglycans, α-dystrobrevin-1 and α1-syntrophin. Double immunofluorescence analysis shows that laminin colocalizes
with dystroglycan, suggesting that similarly to muscle and astrocytes, the DAPC interacts with the extracellular matrix in
pituicytes. Collectively these findings show that dystrophins/utrophins and members of the DAPC are expressed in pituicytes
where they may form multiprotein complexes and play a role in the retraction-reinsertion of pituicyte endfeet during specific
physiological conditions. 相似文献
65.
Shaymaa Obaid Abdullah Ghazi Mohamad Ramadan Hayder Abdul-Amir Makki Al-Hindy Mazin Jaafar Mousa Amir Al-Mumin Safa Jihad Suhad Hafidh Yaqeen Kadhum 《Reports of Biochemistry & Molecular Biology》2022,11(1):182
Background:The contribution of neutrophils is still indistinct in the inflammatory response of bronchial asthma (BAs). Myeloperoxidase (MPO) is an enzyme released from the primary azurophilic granules of the neutrophils. The study aimed to evaluate the levels of serum MPO as a biomarker for the assessment of the level of asthma control. Methods:The study participants included 94 asthmatic patients and 86 healthy controls. The identification of asthma severity had assessed using the ''''Global Initiative for Asthma guidelines''''. Asthmatic adults had divided into three groups: Good (n= 22), partial (n= 30), and poor control (n= 44). Also, patients have been divided again into two groups (treated and untreated) for BAs.Results:The predicted FEV1% and the peak expiratory flow (PEF/L) of all participants had verified by spirometry. The mean patients’ age was 31.9±15.1 year, with a predominance of females. The mean asthma duration was 10.5±8.6 years. Mean spirometric parameters (FEV1 and PEF) were significantly lower among the patients (0.00). Significant higher MPO levels had observed among BAs patients (p-0.00). The MPO levels have not differed significantly with asthma levels and had significant differences with the history of treatment. There was a nonsignificant negative correlation between the mean MPO levels and the spirometry variables among the patients. ROC curves revealed a sensitivity, specificity, accuracy for MPO (80.9%, 72.1%, and 84.3%), respectively to predict asthmatic severity.Conclusion:There were significantly higher MPO levels compared to healthy controls. Levels of serum MPO had a non-significant positive correlation with levels of asthma control, but a negative non-significant correlation with spirometric results. Key Words: Asthma, And Neutrophils, FEV1, MPO, PEF 相似文献
66.
Cell-free synthesis of a functional ion channel in the absence of a membrane and in the presence of detergent 总被引:3,自引:0,他引:3
We have investigated the possibility of cell-fee synthesis of membrane proteins in the absence of a membrane and in the presence of detergent. We used the bacterial mechanosensitive channel MscL, a homopentamer, as a model protein. A wide range of nonionic or zwitterionic detergents, Triton X-100, Tween 20, Brij 58p, n-dodecyl beta-D-maltoside, and CHAPS, were compatible with cell-free synthesis, while n-octyl beta-D-glucoside and deoxycholate had an inhibitory effect. In vitro synthesis in the presence of Triton X-100 yielded milligram amounts of MscL per milliliter of lysate. Cross-linking experiments showed that the protein was able to oligomerize in detergents. When the purified protein was reconstituted in liposomes and studied by the patch-clamp technique, its activity at the single-molecule level was similar to that of the recombinant protein produced in Escherichia coli. Cell-free synthesis of membrane proteins should prove a valuable tool for the production of membrane proteins whose overexpression in heterologous systems is difficult. 相似文献
67.
Production of biogas from solid organic wastes through anaerobic digestion: a review 总被引:2,自引:0,他引:2
Anaerobic digestion treatments have often been used for biological stabilization of solid wastes. These treatment processes generate biogas which can be used as a renewable energy sources. Recently, anaerobic digestion of solid wastes has attracted more interest because of current environmental problems, most especially those concerned with global warming. Thus, laboratory-scale research on this area has increased significantly. In this review paper, the summary of the most recent research activities covering production of biogas from solid wastes according to its origin via various anaerobic technologies was presented. 相似文献
68.
Overexpression of monodehydroascorbate reductase in transgenic tobacco confers enhanced tolerance to ozone,salt and polyethylene glycol stresses 总被引:1,自引:0,他引:1
Eltayeb AE Kawano N Badawi GH Kaminaka H Sanekata T Shibahara T Inanaga S Tanaka K 《Planta》2007,225(5):1255-1264
Ascorbate (AsA) is a major antioxidant and free-radical scavenger in plants. Monodehydroascorbate reductase (MDAR; EC 1.6.5.4)
is crucial for AsA regeneration and essential for maintaining a reduced pool of AsA. To examine whether an overexpressed level
of MDAR could minimize the deleterious effects of environmental stresses, we developed transgenic tobacco plants overexpressing
Arabidopsis thaliana MDAR gene (AtMDAR1) in the cytosol. Incorporation of the transgene in the genome of tobacco plants was confirmed by PCR and Southern-blot analysis
and its expression was confirmed by Northern- and Western-blot analyses. These transgenic plants exhibited up to 2.1-fold
higher MDAR activity and 2.2-fold higher level of reduced AsA compared to non-transformed control plants. The transgenic plants
showed enhanced stress tolerance in term of significantly higher net photosynthesis rates under ozone, salt and polyethylene
glycol (PEG) stresses and greater PSII effective quantum yield under ozone and salt stresses. Furthermore, these transgenic
plants exhibited significantly lower hydrogen peroxide level when tested under salt stress. These results demonstrate that
an overexpressed level of MDAR properly confers enhanced tolerance against ozone, salt and PEG stress. 相似文献
69.
We studied the distribution of the D/D, I/D, and I/I genotypes of the angiotensin-converting enzyme (ACE) in a sample of healthy Lebanese individuals to assess their prevalence
and compare them with other populations. ACE genotypes were determined using the Cardiovascular Disease (CVD) StripAssay,
which is based on a Polymerase Chain Reaction-Reverse hybridization technique. DNA from 133 unrelated healthy donors from
our HLA-bank was used. The prevalence of D/D, I/D, and I/I genotypes was found to be 39.1, 45.1, and 15.8% respectively, with D and I allelic frequency of 61.7 and 38.3%, respectively. The sampled Lebanese population showed ACE genotypic distributions similar
to Caucasians; however, with tendency towards harboring high D allele frequency together with a low I allele frequency just like the Spanish population. This first report from Lebanon will serve as a baseline statistical data
for future investigations of the prevalence of ACE genotypes in association with various clinical entities notably cardiovascular
diseases. The medical literature was also reviewed in this context. 相似文献
70.
In follicular lymphoma the frequency of translocation t(14;18) varies considerably across different geographic regions ranging
from up to 89% among the American follicular lymphoma to around 30% in the Japanese lymphoma. Neighboring and regional countries
varied in their frequency reporting like in Israel (22 of 36 cases; 61%), Turkey (46 of 67 cases; 68.7%), and Jordan (4 of
5 cases; 80%). To our knowledge, this is the first study conducted in Lebanon to determine the frequency of this translocation
in follicular lymphoma patients. Of 42 cases diagnosed with follicular lymphoma at the American University of Beirut Medical
Center, amplifiable DNA was extracted from the corresponding paraffin embedded tissues and tested for t(14; 18) translocation
using PCR amplification of the MBR and MCR breakpoints (INVIVOSCRIBE, CA, USA). We found that 19 patients were positive for
t(14; 18) (45.2%) while 23 were negative (54.8%). Among the 19 positive cases, bcl2 was positive in 10 cases (52.6%). The
majority of the cases were positive for MBR (40.47%), while only two cases were positive for MCR (4.76%). This study expands
the geographical map of the distribution of bcl-2 gene rearrangement in follicular lymphoma patients in the Middle East region.
The interesting low frequency of t(14;18) in Lebanese follicular lymphoma patients (45.2%) stands out among several other
increased frequencies in surrounding and regional countries. In addition, in this patient population, there is a decreased
frequency of the MBR breakpoint (40.47%) while that reported in the literature ranges from 50 to 60%. 相似文献