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排序方式: 共有423条查询结果,搜索用时 15 毫秒
411.
412.
The sequence structure of the ribosomal internal transcribed spacer 2 (ITS2) was determined for six species of Khawia (Cestoda: Caryophyllidea), parasites of cyprinid fish in the Holarctic Region. Homologous intragenomic ITS2 structure was found in Khawia armeniaca, Khawia baltica, and Khawia rossittensis; whereas divergent intragenomic ITS2 copies were detected in Chinese, Japanese, and Slovak isolates of Khawia sinensis and in Khawia japonensis, both parasitic in common carp, and in Khawia saurogobii, recently described from Chinese lizard gudgeon in China. Despite distinct morphological differences between K. saurogobii and K. sinensis, both species display very high level of molecular homogeneity. Variation in number of short repetitive motifs [(GCCT)( n ) (GCCC)( n )], [(GTG)( n )], [(ATAC)( n )], [ACGTGT (TCGTGT)( n )], [(GT)( n )], [(GT)( n )], and [(ACCT)( n ) (GCCT)( n )] resulted in assortment of ITS2 sequences in four ITS2 variants in K. saurogobii from China, three in Chinese and Japanese isolates of K. sinensis, and five ITS2 variants in K. sinensis from Slovakia. In K. japonensis, the structure and arrangement of microsatellites was different from those of K. sinensis and K. saurogobii. The heterogeneity in the number of two microsatellite regions [(TG)( n ); (TTG)( n )] divided ITS2 clones into two variants-first ITS2 variant (472?bp) with (TG)(5) and (TTG)(6), and second variant with (TG)(7) and (TTG)(2) (465?bp). Sequence identity of K. saurogobii with all but one (K. sinensis) congeneric species ranged between 49.5 and 69.2?%, which corresponds to the interspecific differences. In contrast, sequence identity of K. saurogobii and K. sinensis (87.6-95.0?%) failed into the range of intraspecific variation determined for K. sinensis samples. This close genetic similarity indicates that recently described K. saurogobii may have undergone morphological divergence as a result of ongoing sympatric speciation by host switching. 相似文献
413.
Žužul S Zgorelec Ž Bašić F Kisić I Mesić M Vađić V Orct T 《Bulletin of environmental contamination and toxicology》2011,86(5):501-505
Spatial and temporal distribution of arsenic levels in soil during the 9 year monitoring period was investigated on four different
soil types in the area of the gas borehole system Podravina in Croatia. Arsenic levels in the PM10 particle fraction were measured periodically at the same locations for 3 years. Arsenic levels in soil significantly depended
on soil types. Elevated levels were found on gleysol vertic, at two sampling sites, with values exceeding 30 mg/kg of arsenic
in soil. Arsenic levels in air were low and they were not significantly different between sampling sites, suggesting that
gas borehole activities have no influence on arsenic levels in the environment. 相似文献
414.
Background: Microvascular anastomotic coupling devices have been available to microsurgeons for over 20 years. Many studies have validated the efficacy of these devices for venous anastomosis. To date, there have been no large reports of their success in the anatomical region with the highest free flap failure rate, the lower extremity. Methods: A retrospective review of 67 consecutive patients who underwent lower extremity microvascular reconstruction performed from August 2003 to September 2010 was performed. Patient charts were reviewed for age, sex, medical comorbidities, etiology of defect, location of defect, flap type, anastomotic technique, complications, flap survival, and limb salvage outcome. Results: No patients returned to the operating room to have an arterial or venous anastomosis revised. Despite 100% vascular anastomosis patency rates in 67 consecutive lower extremity free flaps, flap survival rate was 95.5%. Total complication rate (13.4%) was due to two partial and one complete flap loss, three infections, two skin graft loses, and one hematoma. There were no intraoperative or perioperative complications involving the use of a microvascular anastomotic coupling device itself. Thirty‐day and long term limb salvage rate was 97% and 92.5%, respectively. Conclusion: Microvascular anastomotic coupling devices create effective venous anastomoses in lower extremity microvascular reconstruction. Thus, it presents an important tool in the armamentarium for lower extremity microsurgical reconstruction. © 2011 Wiley‐Liss, Inc. Microsurgery 2011. 相似文献
415.
416.
Tomislav Strinic Marko Vulic Snjezana Tomic Vesna Capkun Ivica Stipic Ivana Alujevic 《Maturitas》2009,64(2):132-135
Objective
This study investigated matrix metalloproteinase-1 (MMP-1) and matrix metalloproteinase-2 (MMP-2) immunohistochemical expression in uterosacral ligament biopsies from women with pelvic organ prolapse (POP), and controls with normal pelvic support.Design
Prospective observational experimental study.Setting
A tertiary Urogynecology Unit and Institute of Pathology, University Hospital Split, Croatia.Population
Women referred for hysterectomy for prolapse or benign gynecological disease.Methods
Eighty postmenopausal women were included in the study after Ethical Committee approval and informed consent. During surgery, uterosacral ligament biopsies were obtained from patients with POP (n = 40) and women without evidence of pelvic floor weakening (n = 40). Immunohistochemistry for MMP-1 and MMP-2 was performed on formaline fixed and paraffin embedded sections. Statistical evaluations were made by Student t-test or χ2 test.Main outcome measures
Immunohistochemical expression of MMP-1 and MMP-2 in the uterosacral ligaments of women with and without genital prolapse.Results
Forty women with POP and 40 controls without POP were included. The controls were matched to the women with POP in age, body mass index, parity and duration of postmenopausis. A significant increase in MMP-1 immunohistochemical expression was seen in uterosacral ligament tissue from women with POP (P = 0.029). In contrast, there was no difference in immunohistochemical expression of MMP-2 between women with POP and those without (P = 0.899).Conclusion
These data suggest that MMP-1 may be marker of collagen degradation. Increased MMP-1 immunohistochemical expression in uterosacral ligaments is associated with urogenital prolapse. 相似文献417.
Reblánová M Spakulová M Orosová M Králová-Hromadová I Bazsalovicsová E Rajský D 《Parasitology research》2011,109(4):1021-1028
Chromosomal characteristics, i.e., number, size, morphology, and location of ribosomal DNA (rDNA) clusters were examined in
two medically important liver flukes, Fasciola hepatica and Fascioloides magna (Fasciolidae), using conventional Giemsa staining and fluorescent in situ hybridization (FISH) with ribosomal 18S rDNA probe.
A comparison of F. magna and F. hepatica karyotypes confirmed significant differences in all chromosomal features. Whilst the karyotype of F. hepatica comprised ten pairs of chromosomes (one metacentric and nine medium-sized subtelocentrics and submetacentrics; 2n = 20, n = 1 m + 5 sm + 4 st; TCL = 49.9 μm), the complement of F. magna was composed of 11 pairs of medium-sized subtelocentrics and submeta-metacentrics (2n = 22, n = 9 st + 1 sm + 1 sm-m; TCL = 35.2 μm). Noticeable differences were found mainly in length and morphology of first chromosome
pair. It was metacentric and 9.0 μm long in F. hepatica while subtelocentric and 4.7 μm long in F. magna. Although FISH with rDNA probe revealed a single cluster of ribosomal genes in both species, conspicuous interspecific differences
were displayed by chromosomal location of ribosomal loci (i.e., NORs). The signals were found on short arms of fifth homologous
pair in F. hepatica; however, they were detected in pericentromeric regions of the long arms of tenth pair in F. magna. The observed cytogenetic differences were interpreted in terms of karyotype evolution of fasciolid flukes; F. hepatica may be regarded phylogenetically younger than F. magna. The present paper provides a pilot study on molecular cytogenetics within a group of hermaphroditic digenetic flukes. 相似文献
418.
Glavičić S Anić I Braut A Miletić I Borčić J 《Australian endodontic journal : the journal of the Australian Society of Endodontology Inc》2011,37(2):51-55
The purpose was to measure and analyse the vertical force and torque developed in the wider and narrower root canals during hand ProTaper instrumentation. Twenty human incisors were divided in two groups. Upper incisors were experimental model for the wide, while the lower incisors for the narrow root canals. Measurements of the force and torque were done by a device constructed for this purpose. Differences between the groups were statistically analysed by Mann-Whitney U-test with the significance level set to P<0.05. Vertical force in the upper incisors ranged 0.25-2.58 N, while in the lower incisors 0.38-6.94 N. Measured torque in the upper incisors ranged 0.53-12.03 Nmm, while in the lower incisor ranged 0.94-10.0 Nmm. Vertical force and torque were higher in the root canals of smaller diameter. The increase in the contact surface results in increase of the vertical force and torque as well in both narrower and wider root canals. 相似文献
419.
We investigated the relationships between functional genetic variants of the 5-HT(2C) receptor and multidrug-resistant protein (MDR1), coding for P-glycoprotein, and second generation antipsychotic (SDA)-induced weight gain among 108 female schizophrenic patients treated with olanzapine or risperidone for up to 4 months. No significant differences in -759C/T allelic and genotype variants of 5-HT(2C) were found between patients who gained more than 7% of their initial weight compared with those who gained less. Haplotype-based analysis of two MDR1 loci, exon 21 G2677T and exon 26 C3435T, revealed a slightly lower representation of the G2677/C3435 haplotype in the >/=7% group. In the subgroup of patients treated with risperidone, we found borderline overrepresentation of 2677T, significant overrepresentation of 3435T variant and borderline overrepresentation of 2677T/3435T haplotype the >/=7% group, whereas G2677/C3435 haplotype was found to be less represented in the >/=7% group. Our data indicate a nonsignificant role of 759C/T 5-HT(2C) in SDA-induced weight gain, and a stronger influence of the MDR1 G2677T and C3435T polymorphisms on risperidone-induced weight gain in female schizophrenic patients. 3435T and 2677T MDR1 variants, both associated with lower P-gp function, might predispose to higher risperidone accessibility to the brain that would lead to stronger effects, including weight gain. 相似文献
420.
Kojundzic SL Dujmovic I Grkovic I Sapunar D 《The International journal of neuroscience》2008,118(12):1748-1762
In order to investigate the relation between changes in epidermal thickness and pain-related behavior in different rat hind paw areas we performed partial denervation using two experimental models of neuropathic pain injury: spinal nerve ligation (SNL) and chronic constriction injury (CCI). Denervation produced significant epidermal thinning in both models. The most pronounced thinning was observed in the lateral paw region of the SNL group. Both models showed increase in hyperalgesic response during the postoperative period and no behavioral differences between testing regions. Our study showed that partial denervation induces regional differences in epidermal thinning but not in pain-related behavior. 相似文献