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601.
The genetic relationship among 103 natural Bacillus thuringiensis isolates was investigated on the basis of polymerase chain reaction amplification of their specific crystal (cry) protein type genes and chromosomal DNA profiling by pulsed-field gel electrophoresis (PFGE). The strains were recovered from the intestines of small wild rodents and insectivores from the Biebrza National Park and the Lomza Landscape Park of the Narew River Valley in north-east Poland. The percentage of B. thuringiensis strains harbouring genes coding for toxins active against Lepidoptera (cry1, cry2, cry9) was very high (64%) compared with that of Diptera-specific strains (cry4, 14%). No strain with cry genes coding for proteins directed against coleopteran larvae and nematodes was found. After digestion with NotI and AscI, only nine PFGE pulsotypes were observed among all isolates, indicating a clonal structure for the B. thuringiensis population from NE Poland. Interestingly, no correlation was observed between the DNA pulsotype strains and their crystal gene content and diversity. These results therefore emphasize the importance of cry gene horizontal transfer occurring among natural isolates of B. thuringiensis.  相似文献   
602.
Crotonic acid as a bioactive factor in carrot seeds (Daucus carota L.)   总被引:1,自引:0,他引:1  
Water extracts from the carrot seed (Daucus carota L.) var. Perfekcja exhibit plant growth inhibitory properties against cress, cucumber, onion and carrot in a dose-dependant manner. This property results from the action of low-and high-molecular components of the extract. The low-molecular component was identified as crotonic acid ((E)-2-butenoic acid). Its presence was also confirmed in other late varieties of carrot. The determined strong herbicidal properties of crotonic acid and its availability after release to soil combined with its high level in seeds suggest that it might be considered as an allelopathic and autotoxic factor in the seeds.  相似文献   
603.
The effects ofcapsaicin, dimethyl sulphoxide and pH changes on transport of sodium and/or chlorine ions in an isolated frog skin, were studied using electrophysiological methods, adapted to evaluation of ionic currents occurring in the epithelial tissues and organs. The experiment consisted in measuring potential difference (PD in mV) of an isolated skin of the aquatic frog, Rana esculenta L., placed in a Ussing apparatus. The ionic transport processes were modified through incubation of the tissue in Ringer solution and in Ringer solution supplemented with amiloride, bumetanide, and also with dimethyl sulphoxide. The direct effect of capsaicin and dimethyl sulphoxide (DMSO) on frog skin was assessed while these compounds were added to the Ussing chamber with a pipette and a peristaltic pump. Adaptive reactions of the tissue were assessed following at least 60-min exposure to those compounds. It has been demonstrated that amiloride-inhibited sodium ion transport and acidification of the incubation medium (pH 6.4) inhibited mechanically induced epithelium reactions. Both compounds, capsaicin and DMSO modified ionic transport processes depending on the mechanical stimulation.  相似文献   
604.
This paper presents the family of a dysmorphic child with the phenotypic features of Turner's syndrome and 5q trisomy, whose parents are both carriers of a balanced translocation. The parents' karyotypes are 46,X,t(X;5)(p11.1;q31) and 45,XY,der(13;14)(q10;q10), respectively.  相似文献   
605.
In this study stool samples from dyspeptic patients and healthy subjects were used for detection of specific Helicobacter pylori antigens and DNA by immunoenzymatic test (PPHpSA) and semi-nested PCR (ureA-PCR), respectively. The H. pylori status was estimated by invasive endoscopy-based rapid urease test and histology or noninvasive urea breath test (UBT), and by serology (ELISA, Western blot). The coincidence of H. pylori-negative invasive tests or UBT and negative antigen or DNA stool tests was very high (mean 95%). The PPHpSA results were found positive for 56% and ureA-PCR for 26% of individuals with H. pylori infection confirmed by invasive tests or UBT. The detection of specific H. pylori antigens and especially DNA in feces is not sufficient as a one-step diagnosis of H. pylori infection.  相似文献   
606.
The study was made to evaluate bone turnover in systemic lupus erythematosus (SLE) patients undergoing long-term glucocorticoid therapy. Thirty-eight female patients with established SLE were compared with a control group consisting from 160 age-matched healthy women. Serum concentrations of proinflammatory cytokines: interleukin-1alpha, interleukin-6, tumor necrosis factor-alpha, granulocyte-macrophage colony stimulating factor (GM-CSF) and some biochemical markers of osteoporosis (osteocalcin, total and bone alkaline phosphatase, procollagen type I carboxyterminal propeptide, carboxyterminal telopeptides of type I collagen--CTx) were measured. Additionally, morning urine excretions of deoxypyridinoline and calcium/creatinin ratios were determined. The forearm densitometry (DXA) was performed in all patients. Bone mineral content (BMC) and bone mineral density (BMD) in the SLE group was not significantly different from the controls, and no relationship was found between the glucocorticoid exposure and the BMC/BMD. However, biochemical markers of bone resorption--CTx and calcium/creatinin ratio--were significantly increased in the patient group. Our results suggest that BMD/BMC is preserved in glucocorticoid-treated SLE patients despite accelerated bone turnover.  相似文献   
607.
The present study shows new chromosomal localisation of four canine cosmid clones in the Chinese raccoon dog genome by using dual colour FISH. This approach facilitates rapid physical localisation of markers and will improve the determination of their order on chromosomes. The present new assignments increase the number of physically mapped markers in the Chinese raccoon dog to 25.  相似文献   
608.
In this study, we assessed the proliferative response of peripheral blood mononuclear leukocytes (PBML) from 33 children/young adolescents with chronic dyspepsia, to H. pylori LPS in the presence and absence of IL-2 as a T cell growth factor. A rapid urease test (RUT) and a presence of Helicobacter-like organisms (HLO) in the biopsy specimens allowed us to distinguish RUT/HLO-positive (17/33) and -negative (16/33) patients. H. pylori LPS alone induced a proliferation of PBML from 4 out of 33 dyspeptic patients. IL-2 increased the prevalence of the response to LPS to 59% and 74% of RUT/HLO-positive and -negative patients, respectively. PBML from RUT/HLO-positive patients responded significantly less intensively to H. pylori LPS in the presence of IL-2, to IL-2 alone and to H. pylori LPS+IL-2. However, there was no difference in PHA-driven proliferation of PBML from the patients of those two groups. A negative correlation between the responsiveness to H. pylori LPS of PBML and occurrence of type B inflammation in gastric mucosa was demonstrated. The results suggest a contribution of H. pylori LPS to an outcome of H. pylori infection. It is speculated that H. pylori LPS by an activation of immunocompetent cells may reduce gastric inflammation, decrease bacterial load and prolong H. pylori infection.  相似文献   
609.
The model synthesis of a C12-aldose was initiated from the easily available dimethyl(benzyl 2,3,4-tri-O-benzyl-alpha-D-manno-heptopyranos-6-ulos-7-yl)phosphonate and 2,3:4,5-di-O-isopropylidene-D-arabinose.  相似文献   
610.
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