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971.
972.
《Reproductive biology》2014,14(3):176-181
In the present study, we evaluated the clinical value of the following parameters: basal anti-Müllerian hormone (AMH), follicle-stimulating hormone (FSH), inhibin B and antral follicle count (AFC) in predicting live birth outcomes. The study involved 603 women undergoing in vitro fertilization (IVF) using the long protocol for controlled ovarian hyperstimulation (COH). Serum levels of AMH, FSH and inhibin B as well as AFC were measured on the first three days of the menstrual cycle prior to the beginning of stimulation. AMH was the only independent parameter that correlated with the chance of live birth. We found that live birth rates of 46.2% (patient age <35 years), 44.7% (35–37 years), 32.1% (38–39) and 15.3% (>39) were associated with concentrations of AMH > 1.4 ng/ml. For the AMH range 0.6–1.4 ng/ml, the live birth rates were 29.3%, 12.5%, 5.6% and 2.7%, respectively, and for AMH concentrations below 0.6 ng/ml the rates were 7.1%, 8.3%, 0% and 5.8%, respectively. Independently of other parameters affecting the chance of live birth, the success rate was the highest when the AMH level was >2 ng/ml, significantly lower when the AMH concentration was about 1 ng/ml, and 0% when the AMH concentration was ∼0.1 ng/ml. In conclusion, this is the first report to demonstrate that AMH level correlated better than age, FSH or inhibin B concentrations or AFC with live birth outcome. Therefore, the basal serum concentration of AMH may become a new, substantial prognostic factor regarding live birth above and beyond other currently available predictors of IVF outcome. 相似文献
973.
Aaron Romo Pierre Badel Ambroise Duprey Jean-Pierre Favre Stéphane Avril 《Journal of biomechanics》2014
In this study, bulge inflation tests were used to characterize the failure response of 15 layers of human ascending thoracic aortic aneurysms (ATAA). Full field displacement data were collected during each of the mechanical tests using a digital image stereo-correlation (DIS-C) system. Using the collected displacement data, the local stress fields at burst were derived and the thickness evolution was estimated during the inflation tests. It was shown that rupture of the ATAA does not systematically occur at the location of maximum stress, but in a weakened zone of the tissue where the measured fields show strain localization and localized thinning of the wall. Our results are the first to show the existence of weakened zones in the aneurysmal tissue when rupture is imminent. An understanding these local rupture mechanics is necessary to improve clinical assessments of aneurysm rupture risk. Further studies must be performed to determine if these weakened zones can be detected in vivo using non-invasive techniques. 相似文献
974.
B. N. Mukherjee A. K. Roychoudhury N. M. Blake S. L. Kate 《American journal of physical anthropology》1982,59(4):367-371
Blood samples of 1,266 individuals were collected from three caste populations; Nava Budha (Mahar), Maratha, and a mixed group of Scheduled castes from each of three districts of Maharashtra, Nagpur, Akola, and Thane. The samples were tested for 12 enzyme systems, viz., AcPh, AK, CA-I, CA-II, Est-D, LDH, MDH, Oxidase, PGM-1, PGM-2, 6-PGD, and PHI. The gene frequencies of these loci are within the ranges observed among the Indian populations so far studied. The total differences in gene frequencies for each polymorphic locus was partitioned into three components, i.e., the differences between caste populations, the differences between regions, and the differences due to interaction between caste populations and regions. The results show that besides caste variation for two loci, Est-D and PGM-1, the gene frequencies for AK, Est-D, and G-6PD loci have different geographical distributions. 相似文献
975.
Satoru Itoh Michiyuki Katoh Kazuhisa Furuhama 《Mutation Research - Genetic Toxicology and Environmental Mutagenesis》2002,520(1-2):133-139
The skin micronucleus test combined with irradiation due to a sunlight simulator having a spectrum almost identical to solar irradiation was used as a novel in vivo testing method for detecting or comparing the photochemical chromosome damage of quinolone antibacterial agents (quinolones). Eight-week-old male SKH1 hairless mice were orally administered once lomefloxacin (LFLX), a strong in vitro photochemical clastogen, at 25 or 50 mg/kg, followed by light irradiation at 7.9–9.4 J/cm2 of ultraviolet A (UVA). Animals were killed on Days 2, 3, 4, 5 or 8 (the dosing day was designated as Day 1), and the incidence of micronucleus in the epidermis was determined. As results, LFLX at either dose caused significant increases in the micronucleus frequency, which peaked on Day 4. These changes tended to return to the control level on Day 8. Then, the micronucleus induction potential of the quinolone derivatives levofloxacin (LVFX) and clinafloxacin (CLFX) at 10, 20 or 40 mg/kg was assessed on Day 4 under the same experimental conditions as for LFLX. Although LVFX was negative even at 40 mg/kg, CFLX dose-dependently induced significant increases in micronucleus frequency at all doses. The correlation of magnitude among the three quinolones in the skin micronucleus test with light irradiation was similar to that in our previous in vitro photochemical clastogenicity study. No significant increase in micronucleus frequency was observed in any of three quinolones employed without light irradiation. In conclusion, the experimental method presented here would be a useful tool for detecting in vivo photochemical chromosome damage and for research on photochemical carcinogenesis of chemicals. 相似文献
976.
《Saudi Journal of Biological Sciences》2017,24(1):155-161
Dissemination of carbapenem resistance via Enterobacteriaceae, particularly among Klebsiella pneumoniae and Escherichia coli, is a major public health concern. Rapid methods for determining antimicrobial susceptibility are important to ensure adequate and appropriate use of antimicrobial agents and to limit the spread of these bacteria. In the current study, we compared the rapidity, sensitivity and specificity of traditional methods and molecular-based Xpert Carba-R PCR assay to identify sixty isolates, (26 E. coli and 34 K. pneumoniae). The specificity of MicroScan was 100% while sensitivity to ertapenem (ERT), imipenem (IMI), and meropenem (MER) was 93%, 68.9%, and 55.17%, respectively. For the modified Hodge test, the specificity was 96.77% and sensitivity was 89.65%. Although some results of phenotypic assays matched with the definite PCR identification, some results were misleading. Out of the 29 positive PCR samples, three samples of K. pneumoniae were negative for the MHT and one E. coli sample was MHT positive but negative for the PCR. Nine samples were positive for the PCR but were determined as carbapenem sensitive by MicroScan. While MicroScan and MHT requires several hours and multi-steps to obtain results, Xpert Carba-R PCR assay takes less than an hour. Therefore, we recommend using Gene xpert Carba-R assay for the optimal carbapenemnase detection with reducing material, manpower and cost. Also it is important to know the type of carbapenemase is present. 相似文献
977.
The agar-gel precipitin technique was used to examine the immunological relationships of the South American frog genus Eupsophus. This taxon shows similarities with the members of the Telmatobiini tribe and presents a characteristic precipitin band, here labelled as A. 相似文献
978.
Ecotoxicity of soils contaminated with industrial and domestic wastewater in western Shenyang, China
SONG Yufang ZHOU Qixing GONG Ping & SUN Tieheng Key Laboratory of Terrestrial Ecological Processes Institute of Applied Ecology Chinese Academy of Sciences Shenyang China Analytical Services Inc. Halls Ferry Road Vicksburg Mississippi USA Key Laboratory of Environmental Engineering of Shenyang Shenyang University Shenyang China 《中国科学:生命科学英文版》2005,48(Z1)
Soil samples were collected from 7 sites in the up-, mid- and down-reach along and nearby the wastewater irrigation channel, western Shenyang of China. The concentrations of selected pollutants (mineral oil, PAHs - polycycle aromatic hydrocarbons and Cd) were determined by UV spectrometer, HPLC and AAS (atomic adsorption spectrometer) spectrometer, respectively. Toxicity effects of soils were evaluated by seedling emergence test with root length of wheat as the end-point and by earthworms test with the mortality rate and inhibition rates of body weight as endpoints. Results showed accumulation of pollutants for most soils with concentration of 200.2 mg·kg-1-1600 mg·kg-1 for mineral oil, 0.33 mg·kg-1-1.81 mg·kg-1 for Cd and 900.16 mg·kg-1 -2737.91 mg·kg-1 for PAHs. The inhibition rates of root elongation were from -20% up to 40 %, and mortality rates of earthworms ranged from 0%-40% from the exposure period of two weeks to eight weeks by sampling interval of two weeks, the inhibition rates of earthw 相似文献
979.
As rigid endoscopes are re-used after minimal invasive surgery, they degrade over time. To guarantee the optical quality of a rigid endoscope, the ScopeControl has been developed to measure key optical parameters such as, light transmission (LT), color correctness (CC), focus (FC), fiber transmission (FT), viewing angle (VA) and field of view (FV). To evaluate the performance of the ScopeControl, five ScopeControls SV (study version) have been tested in six hospitals in the Netherlands. Aspects such as robustness, precision, usability of the measured data, acceptation criteria and ergonomic aspects have been assessed. The ScopeControl maintains its stability over time and can measure LT, CC and FC with 5% precision, VA and FV with 2% accuracy and FT with 10% precision. The final thresholds above which an endoscope could still be considered to be in good condition, appeared to be: VA at 75%, CC, FC and FV at 70%, LT at 65% and FT at 35% of that of the best endoscope of that type ever found. The ScopeControl SV fits the workflow of the sterilization department as it is easy to use and can easily be cleaned. The time to perform a measurement is 2–3 min (one minute is spent to select the correct endoscope). The ScopeControl PV (launched in November 2013), has been used clinically from April to November 2014. It proves to be more stable, well accepted by personnel from the sterilization department and be of large value of preventing defect endoscopes on the surgery table. 相似文献
980.
Francesco Fantozzi Cinzia Buratti 《Bioresource technology》2011,102(19):8885-8892
One of the more promising processes for the energetic transformation of waste is the anaerobic digestion of the Organic Fraction of Municipal Solid Waste (OFMSW). An experimental campaign was carried out on three different samples of OFMSW from Waste Separation (WS), one as received and two obtained after mechanical treatment (squeezing): OFMSW slurry (liquid fraction) and OFMSW Waste (residual solid fraction). Anaerobic Biogasification Potential (ABP) and anaerobic digestion tests (AD) were carried out, investigating the effects of inoculum and pH. The OFMSW Waste was also examined to evaluate the possibility to dispose of it in a landfill. Results showed that OFMSW slurry must be diluted and inoculated and that pH control in the start up phase is essential, in order to have significant biogas productions. OFMSW as received did not show a significant biogas production, while OFMSW Waste showed suitable characteristics for landfill disposal, except for Dissolved Organic Carbon. 相似文献