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排序方式: 共有647条查询结果,搜索用时 616 毫秒
1.
The authors study by means of immunoperoxidase method the pattern of thyroglobulin, triiodothyronine and thyroxine distribution in 58 cases of thyroid disorders: 15 euthyroid goiters, 10 Graves' disease, 7 Hashimoto's thyroiditis, 11 folliculo-papillary carcinomas (6 primary tumors and 5 lymph node metastases), 8 follicular carcinomas, 4 anaplastic carcinomas and 3 medullary carcinomas. Thyroglobulin, triiodothyronine and thyroxine were present in most of the thyroid disorders, excepting anaplastic and medullary carcinomas. Thyroglobulin and thyroxine were localized both in the follicular epithelium and in the colloid, whereas triiodothyronine was present especially in the follicular cells. The thyroid hormones distribution in benign lesions is rather similar. In carcinomas, the pattern of thyroglobulin, triiodothyronine and thyroxine is more heterogeneous, but generally the triiodothyronine distribution is similar to that of thyroglobulin. In some carcinomas, triiodothyronine and thyroxine showed a weak or negative immunostaining. The immunoperoxidase method is a valuable tool in the study of functional disturbances in the thyroid pathology and in the diagnosis of thyroid carcinoma metastases as well. Positive thyroid hormones staining clearly indicates the thyroid origin of metastases.  相似文献   
2.
The nature of neurone response of substance nigra (SN) to nociceptive stimulation of the cat's peroneal nerve has been studied. The recording of neurone SN firing rate revealed that the majority (71.0%) of the SN neurones responded to the nociceptive repetitive stimulation of the peroneal nerve. But the thresholds of nociceptive activation in SN neurones turned to be very high. As a result of it the number of SN neurones responding to repetitive peroneal stimulation was twice as many as the number of cells responding to single stimulation of the nerve. The intravenous injection of naloxone in dose 1.0 mg/kg changed both excitatory and inhibitory responses in majority (71.4%) of SN neurones responding to repetitive peroneal stimulation. Naloxone did not modify the firing rate of neurones nonresponsive to nociception.  相似文献   
3.
Sunflower honey (SH) is bright yellow, fragrant, pollen-flavoured, slightly herbaceous and has a unique taste. The present research aims to examine the enzyme inhibitory, antioxidant, anti-inflammatory, antimicrobial and anti-quorum sensing activities and phenolic compositions of 30 sunflower honeys (SHs) produced from several regions of Turkey with chemometric study. SAH from Samsun exhibited the best antioxidant activity in β-carotene linoleic acid (IC50: 7.33±0.17 mg/mL) and CUPRAC (A0.50: 4.94±0.13 mg/mL) assays, anti-urease activity (60.63±0.87 %) and anti-inflammatory activity against COX-1 (73.94±1.08 %) and COX-2 (44.96±0.85 %). SHs exhibited mild antimicrobial activity against the test microorganisms while they showed high quorum sensing inhibition zones measured in the range of 42–52 mm against the CV026 strain. The phenolic composition was determined by high performance liquid chromatography with diode array detection (HPLC-DAD) system and levulinic, gallic, p-hydroxybenzoic, vanillic and p-coumaric acids were identified in all studied SHs. The classification of SHs was performed the using PCA and HCA. This study revealed that phenolic compounds and biological properties are effective in classification of SHs according to their geographical origin. The results suggest that studied SHs could be valued as potential agents with versatile bioactivities in oxidative stress-related disease, microbial infections, inflammation, melanoma, and peptic ulcer.  相似文献   
4.
粘虫颗粒体病毒的增效因子提高杆状病毒的感染   总被引:13,自引:4,他引:9  
丁翠  邓塔 《昆虫学报》1995,38(4):407-413
一株美洲粘虫GV(增效品系)在东方粘虫幼虫上进行增殖,所获粘虫GV(PuGv-Ps>对东方粘虫NPV(PsNPV)、棉铃虫NPV(HaNPV)和黄地老虎NPV(AsNPV)进行增效试验。 实验结果证明PuGV-Ps对三种NPV都有明显的增效作用, 其中以对PsNPV为最强,增效率达55%一85%;对HaNPV为30%-80%;而对AsNPV只有15%-35%。用凝胶过滤技术从PuGV-Ps中分离增效因子PusF-Ps,其对PsNPV和A,NPV的增效作用亦同样明显,250μg的PuSF-Ps可以提高PsNPV的感染能力达80%。经ScPhadcf-150柱(1.6X 90)和使用四种标准蛋白(细胞色素c、胃蛋白酶、牛血清清蛋白和乳酸脱氢酶)测得PuSF-Ps的分子量为160 000左右。  相似文献   
5.
G J Pazour  C N Ta    A Das 《Journal of bacteriology》1992,174(12):4169-4174
The virulence (vir) genes of Agrobacterium tumefaciens Ti plasmids are positively regulated by virG in conjunction with virA and plant-derived inducing molecules. A procedure that utilizes both genetic selection and a genetic screen was developed to isolate mutations in virG that led to elevated levels of vir gene expression in the absence of virA and plant phenolic inducers. Mutants were isolated at a frequency of 1 in 10(7) to 10(8). Substitution mutations at two positions in the virG coding region were found to result in the desired phenotype. One mutant had an asparagine-to-aspartic acid substitution at residue 54, and the other contained an isoleucine-to-leucine substitution at residue 106. In both cases, the mutant phenotype required the presence of the active-site aspartic acid residue at position 52. Further analysis showed that no other substitution at residue 54 resulted in a constitutive phenotype. In contrast, several substitutions at residue 106 led to a constitutive phenotype. The possible roles of the residues at positions 54 and 106 in VirG function are discussed.  相似文献   
6.
Escherichia coli contains a soluble, [2Fe-2S] ferredoxin of unknown function (Knoell, H.-E., and Knappe, J. (1974) Eur. J. Biochem. 50, 245-252). Using antiserum to the purified protein to screen E. coli genomic expression libraries, we have cloned a gene (designated fdx) encoding this protein. The DNA sequence of the gene predicts a polypeptide of 110 residues after removal of the initiator methionine (polypeptide M(r) = 12,186, holoprotein M(r) = 12,358). The deduced amino acid sequence is strikingly similar to those of the ferredoxins found in animal mitochondria which function with cytochrome P450 enzymes and to the ferredoxin from Pseudomonas putida which functions with P450cam. The overall sequence identity is approximately 36% when compared with human mitochondrial and P. putida ferredoxins, and the identities include 4 cysteine residues proposed to coordinate the iron cluster. The protein was overproduced approximately 500-fold using an expression plasmid, and the holoprotein was assembled and accumulated in amounts exceeding 30% of the total cell protein. The overexpressed ferredoxin exhibits absorption, circular dichroism, and electron paramagnetic resonance spectra closely resembling those of the animal ferredoxins and P. putida ferredoxin.  相似文献   
7.
The authors describe histopathologic aspects in ten cases of thyroid carcinoma with amyloid stroma. This form of cancer represents 3.4% of all the thyroid cancer cases in the last five years in the Institute of Endocrinology. Microscopic examination reveals a polymorphous picture alongside with amyloid deposits. The authors attribute to the tumor cells an important role in producing thyroid amyloidosis.  相似文献   
8.
Recent studies have revealed the critical role of several microRNAs (miRNAs) in energy homeostasis and metabolic processes and suggest that circulating miRNAs can be used as early predictors of weight loss in the design of precision nutrition. Thus, the aim of this study was to investigate circulating adiposity-related miRNAs as biomarkers of the response to two specific weight loss dietary treatments. The expression of 86 miRNAs was investigated in plasma of 78 subjects with obesity randomized to two different diets [moderately high-protein diet (n = 38) and low-fat diet (n = 40)] and in 25 eutrophic controls (BMI ≤ 25 kg/m2). Bioinformatic analyses were performed to explore the target genes and biological pathways regulated by the dysregulated miRNAs. As results, 26 miRNAs were found differently expressed in eutrophic and volunteers with obesity. Moreover, 7 miRNAs (miR-130a-3p, miR-142-5p, miR-144-5p, miR-15a-5p, miR-22-3p, miR-221-3p and miR-29c-3p) were differentially expressed between responders and non-responders to a low-fat diet. Furthermore, after adjustment for basal glucose levels, 1-SD increase in miR-22-3p expression was associated with reduction in the risk of non-response to low-fat diet [OR = 0.181, 95% CI (0.084-0.947), P = .043]. Bioinformatic analyses evidenced that these 7 miRNAs regulate the expression of genes participating in important metabolic pathways. Conclusively, 7 circulating miRNAs related to adiposity could be used for predicting the response to a low-fat diet intervention prescribed to lose weight.  相似文献   
9.
The antioxidant activity of some amido-carbonyl oximes containing a C=O and –NH–R adjacent to the oxime group, [Phenyl-C(=O)-C(=N-OH)-N(-H)-Phenyl(-R)] where R= H, 4-chloro, 4-methyl, 4-methoxy, 3,4-dichloro, 3,4-dimethyl, 3-chloro-4-dimethyl, 3-chloro-4-methoxy, naphthyl and an amido-carbonyl dioxime were investigated in vitro by ferric thiocyanate, total reducing power by potassium ferricyanide reduction, 1,1-diphenyl-2- picryl-hydrazyl (DPPH·) free radical scavenging, ferrous ions chelating, superoxide anion radical scavenging and hydrogen peroxide scavenging activity assays. The results indicated that the amido-carbonyl oximes have powerful antioxidant capacity.  相似文献   
10.

Background

L. tropica can cause both cutaneous and visceral leishmaniasis in humans. Although the L. tropica-induced cutaneous disease has been long known, its potential to visceralize in humans was recognized only recently. As nothing is known about the genetics of host responses to this infection and their clinical impact, we developed an informative animal model. We described previously that the recombinant congenic strain CcS-16 carrying 12.5% genes from the resistant parental strain STS/A and 87.5% genes from the susceptible strain BALB/c is more susceptible to L. tropica than BALB/c. We used these strains to map and functionally characterize the gene-loci regulating the immune responses and pathology.

Methods

We analyzed genetics of response to L. tropica in infected F2 hybrids between BALB/c×CcS-16. CcS-16 strain carries STS-derived segments on nine chromosomes. We genotyped these segments in the F2 hybrid mice and tested their linkage with pathological changes and systemic immune responses.

Principal Findings

We mapped 8 Ltr (Leishmania tropica response) loci. Four loci (Ltr2, Ltr3, Ltr6 and Ltr8) exhibit independent responses to L. tropica, while Ltr1, Ltr4, Ltr5 and Ltr7 were detected only in gene-gene interactions with other Ltr loci. Ltr3 exhibits the recently discovered phenomenon of transgenerational parental effect on parasite numbers in spleen. The most precise mapping (4.07 Mb) was achieved for Ltr1 (chr.2), which controls parasite numbers in lymph nodes. Five Ltr loci co-localize with loci controlling susceptibility to L. major, three are likely L. tropica specific. Individual Ltr loci affect different subsets of responses, exhibit organ specific effects and a separate control of parasite load and organ pathology.

Conclusion

We present the first identification of genetic loci controlling susceptibility to L. tropica. The different combinations of alleles controlling various symptoms of the disease likely co-determine different manifestations of disease induced by the same pathogen in individual mice.  相似文献   
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