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排序方式: 共有192条查询结果,搜索用时 46 毫秒
51.
伊犁河谷地下水及土壤盐分分布特征 总被引:3,自引:0,他引:3
利用化学分析和地统计学法,分析了研究区地下水以及土壤盐分含量、离子组成特征及其分布规律.结果显示:地下水矿化度平均值为2.37 g/L,pH值平均值为7.63,地下水中各阴离子含量由高到低依次为Cl->SO42->HCO3->CO32-,阳离子含量由高到低依次为Ca2+>Na+>Mg2+>K+,地下水属于Cl--Ca2... 相似文献
52.
53.
Sardari K Chavez-Muñoz C Kilani RT Schiller T Ghahary A 《Canadian journal of veterinary research》2011,75(4):271-277
The present study investigated whether the 14-3-3 η and γ proteins, which are potent matrix metalloprotease (MMP) stimulators, are detectable in the synovial fluid of dogs with cranial cruciate ligament rupture (CCLR). Synovial fluid samples from 7 dogs with unilateral CCLR and control samples from 4 dogs without a history of any joint inflammation or any other abnormalities underwent Western blot analysis for the 14-3-3 η, γ, and σ proteins as well as MMP-1 and MMP-3. Craniocaudal and lateral radiographic projections of the stifle joint were evaluated for the presence and severity of 13 specific radiographic markers of osteoarthritis and graded numerically. The Spearman method was used to detect any correlation between the 14-3-3-η level in the synovial fluid and the radiograph-based grade. The η isoform was present only in the samples from the dogs with CCLR. The levels of 14-3-3-γ, MMP-1, and MMP-3 were significantly higher in the samples from the dogs with CCLR than in the control samples (P < 0.05). However, there was no significant difference between the CCLR and control samples in the level of the σ isoform. The Spearman method showed a significant correlation between the 14-3-3-η level in the synovial fluid and the presence of either patellar osteophytes or lateral or medial (or both) condylar periarticular osteophytes (P < 0.05). The MMP stimulatory effect of the 14-3-3 η and γ isoforms may be the reason for the high levels of MMP-1 and MMP-3 observed. Thus, 14-3-3 proteins, especially the η isoform, may be important markers of osteoarthritis caused by CCLR. 相似文献
54.
There is a high diversity among cultivated walnut trees in Iran due to its long time of seed propagation and vast area of cultivation. In this study some morphological characters as well as Simple Sequence Repeat (SSRs) markers were used to analyze the genetic diversity and relationships among 31 Iranian walnut genotypes along with four foreign cultivars. The nut weight ranged from 7.52 to 17.73 g, kernel weight from 4.00 to 9.83 g, and kernel percentage ratio from 38.78 to 67.05% among studied genotypes. In SSRs analysis, nine primer pairs were tested that produced 39 alleles ranging from 2 to 8, with a mean value of 5.10 allele per primer. The Iranian genotypes showed relatively high diversity both for their SSRs loci and morphological traits. Although the foreign cultivars (‘Serr’, ‘Vina’, ‘Franquette’ and ‘Lara’) clustered with each other, they also laid close and within the Iranian genotype. The results of the study provided us with valuable diversity among our genotypes which could be used for breeding studies and also showed the power of genetic markers for analysis and evaluation of this diversity. 相似文献
55.
These studies were designed to measure leukotriene B4 (LTB4) production by polymorphonuclear leukocytes (PMN) from selenium (Se)-deficient and Se-adequate goats. Leukotriene B4 was measured by both radioimmune and chemotactic activity assays in supernatants of PMN stimulated by calcium ionophore A23187. The concentration of LTB4 produced by PMN from Se-deficient goats was significantly (P less than 0.05) lower than the concentration of LTB4 produced by PMN from Se-adequate goats. Neutrophil chemotactic activity of LTB4 was found to be directly dependent (r2 = 0.85) on the LTB4 concentration. When supernatants from Se-deficient and Se-adequate goats were adsorbed with caprine neutrophils, significant (P less than 0.05) reduction in LTB4 was found in supernatants from both groups. Furthermore, neutrophil adsorption of LTB4 from supernatants of both groups was indicated by significantly (P less than 0.05) decreased chemotaxis to LTB4 supernatants. Decrease in chemotactic response was, however, significantly (P less than 0.05) lower when neutrophils were treated with supernatants from Se-deficient goats. These results indicate that Se deficiency decreases the production of LTB4 by caprine PMN and, hence, LTB4-mediated neutrophil chemotaxis. 相似文献
56.
D Llanes C Arce J P de la Lastra D de Andrés M Barbancho L Morera A Moreno C Lucena A Jimenez-Marín Y E Abdel Aziz G Pa?os J J Garrido K Haverson 《Veterinary immunology and immunopathology》2001,80(1-2):131-142
A total of 14 antibodies were found to label resting and/or activated swine platelets. Six recognized CD previously characterized for swine (CD29, CD41/61 and CD46). One had been characterized for human cells (CD47). Two antibodies with CD14 and SLA class I specificity suggested by the donor as well as five blind antibodies were also positive on platelets. One antibody appeared to recognize the swine homologue to human CD47, and four remained unclustered. 相似文献
57.
S A Youssef A Ramadan N A Afifi M D Aziz 《DTW. Deutsche tier?rztliche Wochenschrift》1991,98(6):213-216
The effect of sodium taurocholate (S. T.) on the contractile response of rat-phrenic nerve diaphragm, frog's musculus rectus abdominis and frog's musculus gastrocnemius sciatic nerve preparation was studied. Moreover, interaction of S. T. with neuromuscular blockers are carried out, too. S. T. was found to have a dose-dependent reduction in the contractile response of the tested preparation. On the other hand, the inhibitory effect induced by S. T. did not block or alter the stimulatory effect of either acetylcholine or prostigmine. Trials were made to estimate the potency of S. T. in a comparison with other skeletal muscle relaxant drugs. In this respect S. T. exhibited a more potent effect than gallamine. In contrast, other skeletal muscle relaxants (dtubocurarine, atracurium, pancuronium and succinylcholine) were highly potent. There was also a marked synergistic effect between S. T. and other neuromuscular agents. 相似文献
58.
Coudry V Jean D Desbois C Tnibar A Laugier C George C 《The Canadian veterinary journal. La revue veterinaire canadienne》2007,48(6):623-626
Ventricular dysrhythmias are more commonly associated with myocardial disease than are supraventricular dysrhythmias. Management of arrhythmias under general anesthesia is difficult because of the dysrhythmogenic effects of the anesthetic drugs. This report describes a severe ventricular dysrhythmia observed in a pony under general anesthesia, with a severe and old myocardial fibrosis found on postmortem examination. 相似文献
59.
Muhammad Nasim Riaz H. Qureshi Tariq Aziz M. Saqib Shafqat Nawaz J. Akhtar 《Journal of plant nutrition》2013,36(9):1427-1439
ABSTRACT We studied the effect of sodium chloride (NaCl) salinity and oxygen deficiency stress on growth and leaf ionic composition of three Eucalyptus species [E. tereticornis, E. camaldulensis (Silverton), and E. camaldulensis (Local)]. Species were grown with control (no NaCl) and salinity (150 mol m?3 NaCl) under hypoxic and non-hypoxic conditions in nutrient solution with five replications following CRD. Species differed significantly in their response to salinity and hypoxia. Absolute shoot dry matter was significantly better in E. camaldulensis (Silverton) in salinity and in E. camaldulensis (Local) in saline hypoxic treatment. E. tereticornis was the most sensitive species to salinity and salinity × hypoxia in the root environment. Sodium (Na+) and chloride (Cl?) concentrations were significantly lower in E. camaldulensis (Local) in non-hypoxic saline treatment compared to the other two species. E. camaldulensis (Silverton) seems to have better tissue compartmentalization, whereas E. camaldulensis (local) seems to have better exclusion of Na+ at the root level. 相似文献
60.
Muhammad Farooq Atique-ur-Rehman Tariq Aziz Mazhar Habib 《Journal of plant nutrition》2013,36(10):1507-1515
Boron (B) is one of the important micronutrient required for rice in particular during reproductive growth. A laboratory study was conducted to explore the potential of boron nutripriming in improving the germination and early seedling growth of rice. Seeds of fine grain aromatic rice cultivar Super Basmati were primed in aerated B solution (0.001, 0.01, 0.1 and 0.5% w/v) while untreated dry seeds were taken as control. Seed priming in 0.001 and 0.1% B solutions improved the time to 50% germination, germination energy, final germination percentage, mean germination time, and germination index. Beyond this concentration either there was no effect or an adverse effect on rice seeds. In the cases of radicle length, plumule length and secondary roots priming more diluted B solution, i.e., 0.001% proved better than rest of the treatments as suppression in these three traits was observed by other B treatments than control. Seed priming in relatively concentrated B solution, i.e., 0.5% completely suppressed the germination and growth. 相似文献