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111.
The uptake of nutrients was investigated in the renal cortical brush border membrane (BBM) vesicles at different stages of ascending pyelonephritis. There was significant difference (p less than 0.05) in the uptake of D-glucose, L-alanine, L-aspartate, L-lysine and L-proline 3 days postinfection and onwards in both right unobstructed and left obstructed experimental kidneys as compared to the sham operated control. The uptake of D-glucose, L-lysine and L-proline was found to be significantly decreased (p less than 0.05) during the course of infection. While uptake of L-alanine and L-aspartate increased (p less than 0.05) in early stages and decreased (p less than 0.05) in later stages of infection. The differential effect was attributed to the compensatory measure and different kinds of transport systems for different types of amino acids.  相似文献   
112.
Metallothionein (MT) a low molecular weight, Cd-binding, cysteine rich, cytosolic protein has been isolated, purified and characterized from cadmium exposed Rhesus monkeys maintained on protein calorie malnourished (PCM) diet. Metallothionein was resolved into three isoforms i.e. MTa, MTb and MTVc. The ratio of Cd, Zn and Cu varied in these isometallothioneins. MTc was the major isometallothionein. UV Spectra of MTc revealed the presence of mercaptide bonds and absence of aromatic amino acids. These observations were further confirmed by amino acid analysis of MTc which demonstrated high cysteine content (22.6) followed by serine, glycine and lysine. The molecular weight of MTc as determined by gel filtration and amino acid analysis was 13000 and 6398 daltons respectively. This demonstrates that MTc is a non-globular ellipsoid polypeptide. MTc showed a unique property of binding selenium. Monkey liver metallothionein was immunologically identical with human metallothionein. All the characteristics of MTc obtained in the present study reveal a similarity between monkey and human metallothionein probably due to closer phylogenetic relationship between the two species.  相似文献   
113.
A 6 kb DNA segment of the R. meliloti 2011 pSym megaplasmid, which contains genes controlling host specificity of root hair infection and of nodulation, was cloned and sequenced. The DNA sequence analysis, in conjunction with previous genetic data, allowed identification of four nod genes designated as E, F, G and H. nodH is divergently transcribed with respect to nodFE and nodG. A conserved nucleotide sequence was found around 200 bp upstream of the translation start of nodF, nodH and nodA. This sequence is also present upstream of common nodA and species specific nodF genes of other Rhizobium species. The predicted protein products of nodF and nodG show homology with acyl carrier protein and ribitol dehydrogenase, respectively. The nodH product contains a rare sequence of four contiguous proline residues. Comparison with the nod gene products of R. leguminosarum shows that species specific nodFE products are as well conserved as those of common nodABC and nodD genes.  相似文献   
114.
115.
Bovine brain contains two major calmodulin (CaM) dependent phosphodiesterase isozymes which are homodimeric proteins with subunit molecular masses of 60 and 63 kilodaltons (kDa), respectively. The 60-kDa subunit isozyme can be phosphorylated by cAMP-dependent protein kinase, resulting in a decrease in the enzyme affinity towards CaM. The phosphorylation is blocked by Ca2+ and CaM and reversed by the CaM-stimulated phosphatase (calcineurin). The 63-kDa subunit isozymes can also be phosphorylated, but in this case by a CaM-dependent protein kinase(s). This phosphorylation is also accompanied by a decrease in the isozyme affinity towards CaM and can be reversed by the CaM-dependent phosphatase. Analysis of the complex regulatory properties of the phosphodiesterase isozymes has led to the suggestion that fluxes of cAMP and Ca2+ during cell activations are closely coupled and that the CaM-dependent phosphodiesterase isozymes play key roles in this signal coupling phenomenon.  相似文献   
116.
Serial sections of 350 nm thickness were used to make a correlation between electron and light microscopic observations. While thionin-acridine orange staining gave a positive result to detect abnormal sieve tubes of phyllody affected Phlox drummondii Hook, when observed under light microscope, the same cells revealed the presence of typical mycoplasmalike organisms (MLOs) in electron microscopic examination. Advantage of 350 nm thick sections in electron microscopy, and the utility of the technique in MLO detection have been discussed.  相似文献   
117.
The witches' broom disease has been recently observed on poplars in Paris and its suburbs. The incidence of the disease appeared to be considerably high along main roads. The electron microscopic examination of 350 nm thick sieve tube sections revealed the presence of wall-less mycoplasmalike organisms (MLOs) in diseased samples of Populus alba var. nivea Wesm. They could not be found in their healthy counterparts.  相似文献   
118.
Underground and aboveground biomass and their ratios at flowering time in different natural stands of Typha angustata near Jaipur, India were studied in the field and experimentally over a period of eleven months (June to April). The underground biomass was 40–50% of the aboveground biomass in both natural and experimental conditions.  相似文献   
119.
Cynaropicrin, 11βH-11,13-dihydrodesacylcynaropicrin, aguerins A and B, isoamberboin and the new guaianolides saussureolide and 11βH-11,13-dihydrodesacylcynaropicrin 8-β-d-glucoside were isolated from Saussurea affinis.  相似文献   
120.
A total of 24 uterine biopsies were successfully obtained from 40 repeat-breeding buffaloes. The endometrium of 15 buffaloes showed marked neutrophilic infiltration in the epithelium, stroma and uterine glands. In some cases, lymphocyte and plasma cell infiltration, cystic dilatation of the glands and periglandular fibrosis indicated chronicity of the endometritis. Most of the animals (85.0%) had uterine cultures positive for Streptococci, Staphylococci, Gram positive variable cocci, Gram negative bacilli, Anthracoids, and Gram positive bacilli with a predominance of Corynebacteria. With the treatment based on in vitro drug sensitivity tests, 57.1% repeat-breeding buffaloes conceived.  相似文献   
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