Mathematics
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 Flush Distance: Bird Tolerance to Human Intrusion in Hangzhou
作者  WANG Yan-ping CHEN Shui-hua DING Ping
作者单位  
期刊  Zoological Research 卷期  Vol. 25, No. 3, 2004 时间  
关键词  Bird; Flush distance; Human intrusion; Adaptation; Influencing factor
摘要   Flush distance, how close one can get to a bird before it flushes, reflects the adaptation of birds to human intrusion.A larger flush distance indicates a lower adaptation to human intrusion.To examine the patterns of the adaptation of birds to human intrusion and its influencing factors,9 dominant and widely-distributed species were selected among 42 species surveyed in Hangzhou,China from September 2002 to January 2003.Based on the differences in vegetation type,building index and disturbance degree,habitats were divided into 5 categories:building areas,urban woodlots,western mountains,ponds and farmlands.Four variables reflecting biological traits of birds (body size,activity height,migratory status,conspicuousness) and one habitat variable (visibility of observation point) were selected to examine their influence on flush distance.We found that:1)The degrees of human intrusions in 5 habitats were significantly different.2)There were significant differences in the flush distance of 9 species among different habitats.Generally,the flush distance was negatively associated with human intrusion.3)The analysis of bivariate correlation showed that flush distance was positively associated with body size and the visibility of observation point,but it was negatively associated with activity height.However,there was no significant association between the flush distance and the conspicuousness of birds.Our results indicated that most species had adapted to human intrusions to some extent,and that the birds with larger body,or those occurred in the habitats with higher visibility or closer to the ground had relatively lower adaptation to human intrusions.
 Phylogenetic Relationships of Megophryid Genera (Anura:Megophryidae) Based on Partial Sequences of M
作者  ZHENG Yu-chi MO Bang-hui LIU Zhi-jun ZENG Xiao-mao
作者单位  
期刊  Zoological Research 卷期  Vol. 25, No. 3, 2004 时间  
关键词  Megophryidae; 16 S rRNA; Phylogeny; Topology
摘要   Phylogenetic relationships of 8 genera of Megophryidae (Anura) were discussed based on 25 partial sequences of mitochondrial 16 S rRNA gene.Maximum likelihood,maximum parsimony,and neighbor joining analyses were performed on the dataset.The ingroup was divided into two major clades,Clade 1 and Clade 2,on the gene tree.Clade 1 included Megophrys,BrachytarsophrysandAtympanophrys,whileLeptolalax,Oreolalax,Scutiger,LeptobrachiumandVibrissaphorabelonged to Clade 2.This met the result of morphological study.It was primarily estimated that the divergence age of two clades occurred 14.2-18.7 million years ago.The topology of Clade 1 did not supportMegophrysto be a monophyletic group.In Clade 2,Leptolalaxwas believed to be a valid genus and was the taxon that occurred much early.
 Comparison of embryo development in sibling oocytes cultured in two different sequential media
作者  Necati Findikli,Semra Kahraman, Ersan Donmez, Semra Sertyel, Sureyya Melil,Moncef Benkhalifa,
作者单位  
期刊  Middle East Fertility Society Journal 卷期  Vol. 9, No. 2, 2004 时间  
关键词  Human embryo development, sibling oocytes, sequential media, severe male infertility
摘要   Objective:To compare the efficiency of two different sequential media for the cultivation of sibling embryos until the blastocyst stage. Design:A prospective analysis was conducted on 113 ART cycles with the indication of severe male factor infertility in Istanbul Memorial Hospital ART and Genetics Unit. Setting: After insemination, oocytes were randomly divided into two groups and cultured with either ISM1/ISM2 or G1.2/G2.2 sequential media until embryo transfer. Embryo development parameters were recorded for every embryo on consecutive days of preimplantation embryo development, growing in each set of culture media. Results:16.7±6.4 MII oocytes were retrieved. Out of 1434 MII oocytes injected, 1044 were fertilized (72.8%). There was no statistically significant difference in the rate of fertilization (p>0.05). Also, there was no difference in embryo development on the second day of cultivation. On the 3rd day of cultivation, the mean number of blastomeres was significantly higher in embryos cultivated within ISM1 (p<0.01). There was no statistically significant difference among the two groups in terms of blastulation rate. Discussion:Both G1.2-G2.2 and ISM1-ISM2 sequential cultures are equally effective for in-vitro cultivation of embryos until the blastocyst stage. Our results show that both commercial media can be used as valuable and efficient alternatives to each other for sustaining blastocyst development in extended embryo culture programs. ISM1 may be preferred when blastomere biopsy for preimplantation genetic diagnosis is planned as more embryos with 7-8 blastomeres can be available with the use of ISM1.
 Electrosonographic evaluation in patients with temporomandibular disorders, treated by interocclusal
作者  Landulpho, Alexandre Brait;Buarque e Silva, Wilkens Aurélio;Andrade e Silva, Frederico;Casselli, Henrique & Buarque e Silva, Lígia Luzia
作者单位  
期刊  Brazilian Journal of Oral Sciences 卷期  Vol. 3, No. 11, 2004 时间  
关键词  craniomandibular disorders, interocclusal appliance, joint sounds
摘要   The purpose of this study was to evaluate, through computerized electrosonography, the effectiveness of interocclusal appliance therapy, used by patients with temporomandibular disorders. Twenty two patients, male and female, ages between 18 and 53 years old, with temporomandibular disorders, were examinated and treated. The electrosonographic evaluations were carried out before the beginning of the treatment and 90, 120, 150 days after using the interocclusal appliance. It is important to emphasize that these appliances received canine guidance and group function modification at the 90th and 120th day, respectively. The collected informations were submitted to statistical analysis of polinomial regression, and revealed had a significant increase in joint sounds frequency in the right TMJ.
 Evaluation of marginal adaptation of ceramic crowns depending on the marginal design and the additio
作者  Hilgert, Edson;Buso, Leonardo;Neisser, Maximiliano Piero & Bottino, Marco Antonio
作者单位  
期刊  Brazilian Journal of Oral Sciences 卷期  Vol. 3, No. 11, 2004 时间  
关键词  dental ceramics, marginal adaptation, finish lines
摘要   This study evaluates the marginal adaptation of ceramic copings front of two finish lines and addition of ceramic. Hence, two master steel dies were milled with all-ceramic crowns preparation, one with a round shoulder finish line margin design, and the other with a deep chamfer. From each one of them, 15copingswere made, and the marginal discrepancy was evaluated in measuring microscope. The ceramic addition was accomplished in both groups with aid of a silicone matrix, and the discrepancies were measured again, obtaining the final mean gap values. The initial measurements resulted means of 44,0μm for deep chamfer and 24,0μm for the round shoulder, and the final measurements were 53,3μm for the deep chamfer and 27,4μm for the round shoulder. The data were submitted to the analysis of variance for verification of influence of the finish lines and application of the ceramic. When analyzed the interaction among the variables it was not observed statistical differences, but when comparing the two types of finish lines or the groups before and after ceramic addition, statistical differences were found. It is was concluded that the round shoulder finish line presents better values of marginal gap than deep chamfer and the addition of ceramic influences in the final gap values of marginal adaptation.
 DEBATE- Ovarian hyperstimulation syndrome: are preventive measures effective?
作者  Basil C. Tarlatzis, Leonidas Zepiridis ,Grigoris Grimbizis
作者单位  
期刊  Middle East Fertility Society Journal 卷期  Vol. 9, No. 2, 2004 时间  
关键词  
摘要   Infertility treatment has been changed dramatically over the last decades with the introduction of the new assisted reproduction techniques (ART). Ovarian stimulation, either to induce ovulation in the management of anovulatory infertility or for controlled ovarian hyperstimulation in the course of in vitro-fertilization, is a main part of the various ART. Nevertheless, ovarian stimulation entails the risk for the development of ovarian hyperstimulation syndrome (OHSS), the commonest complication as such. Hence, it is of great importance not only to know how to effectively induce ovulation but also how to prevent this severe potential risk. Ovarian hyperstimulation syndrome is a well-known and important complication of ovulatory drugs. Its development has been described following ovulation induction with almost every drug used for ovarian stimulation, either in the management of anovulatory infertility or during controlled ovarian hyperstimulation for in-vitro fertilization, having an incidence of 0,5-2% (1). The employment of gonadotropin releasing hormone-agonists (GnRH-a) seems to be associated with an increased incidence of OHSS (2-4).
 Weight Loss During Prolonged Lactation in Rural Bangladeshi Mothers
作者  Sarkar, Nihar Ranjan & Taylor, Richard
作者单位  
期刊  The Journal of Health, Population and Nutrition 卷期  Vol. 23, No. 2, 2005 时间  
关键词  Lactation; Breastfeeding; Body-weight; Anthropometry; Food consumption; Cross-sectional studies; Bangladesh
摘要   To determine the duration of lactation which is associated with weight loss in rural Bangladeshi mothers and also to determine the relationship with consumption patterns of principal food items, a cross-sectional study was carried out among 791 lactating rural Bangladeshi mothers aged 18-40 years. Results were compared with 333 non-pregnant and non-lactating mothers of a similar age group. The duration of lactation was up to 60 months. The mean difference in body-weight and body mass index (BMI) of lactating mothers who breastfed their children up to 24 months was significantly lower compared to non-lactating mothers of the same age group, but no differences were observed for those who breastfed beyond 24 months. The frequency of consumption of principal food items was comparable between the non-lactating and the lactating mothers who breastfed beyond 24 months. Results of multiple linear regression analysis showed that body-weight of mothers was negatively correlated with 1-12 month(s) and 13-24 months of lactation after controlling for height, education, and food consumption (slope -1.04, p<0.05 and slope-1.23, p<0.05 respectively). Height and consumption of meat and milk were significantly positively correlated with body-weight(slope 0.53,p<0.001; slope 1.44, p<0.001;and slope 0.75,p<0.05 respectively). The study concluded that Bangladeshi women who breastfed up to 24 months were of lower weight than non-lactating mothers, most likely due to the effect of lactation. These mothers were not taking any additional foods during their lactating period. Based on the findings of the study, it is recommended that mothers consume additional energy-rich foods during the first 24 months of lactation to prevent weight loss.
 Ovulation prediction in spontaneous and induced cycles: the role of ovarian reserve markers
作者  Amgad O. Gohar, A.R. El-Edwi, HossamELDin S.H. Abdallah
作者单位  
期刊  Middle East Fertility Society Journal 卷期  Vol. 9, No. 1, 2004 时间  
关键词  Ovulation prediction, FSH, Inhibin-B, estradiol, transvaginal ultrasound, antral follicle count AFC, ovarian volume OV, Infertility
摘要   Objective(s):To evaluate the role of day 3 serum; FSH, inhibin-B and estradiol, (biochemical markers), ultrasound measured antral follicle count AFC and ovarian volume OV (biophysical markers) in ovulation prediction in induced cycles in infertile patients with different induction protocols. Also, the secondary aim was to analyze the correlations between these markers and prediction of ovulation success in induced cycles with different induction protocols. Design:Prospective comparative controlled study Settings:Infertility Clinic, University Hospital , El Minia & IVF center, Egypt . Patients:Eighty infertile patients (study group) classified into four subgroups, twenty patients each according to the method of ovulation induction and twenty matched fertile subjects (control group). Interventions:Day 3 serum; inhibin-B, FSH and estradiol were measured together with transvaginal ultrasound measurements of the antral follicle count and ovarian volume in the study and the control groups. The study group was subdivided into four subgroups according the method of ovulation induction; whether clomiphene citrate (group I), or urinary follicle stimulating hormone (group II), or low dose recombinant follicle stimulating hormone (group III) or long protocol (group IV). Main outcome measures:The predictive values of different screening markers in relation to ovulation. Other outcome measures were the analysis of the correlations between various biochemical and biophysical markers and prediction of ovulation success in induced cycles with different induction protocols. Results:The predictive values of FSH (45 pg/ml), estradiol (6), and OV (>3 cm3) in relation to ovulation prediction were statistically comparable (P>0.05). Multivariate analysis of the variables that predict ovulation in induced cycles demonstrated that of the biochemical variables FSH was the most significant contributor to ovulation (R2 = 0.93, P ≤ 0.01), while of the biophysical variables AFC is the most significant one (R 2= 0.46, P ≤ 0.01). Conclusions:Day 3 serum; FSH, inhibin-B and estradiol, ultrasound measured AFC and ovarian volume are comparable screening markers of the ovarian reserve in the general infertility patients. Of the biochemical factors the main predictor for ovulation in induced cycles is FSH while AFC is the main biophysical one.
 Effect of Ration Level on Growth in Juvenile Soft-shelled Turtles, Trionyx sinensis
作者  LEI Si-jia YE Shi-zhou
作者单位  
期刊  Zoological Research 卷期  Vol. 25, No. 1, 2004 时间  
关键词  Juvenile Trionyx sinensis; Ration level; Growth; Conversion efficiency
摘要   The growth trial of a 56-day period was conducted at 30 ° to investigate the effect of ration on growth and feed conversion efficiency in juvenilesTrionyxsinensis ,which initial body weights ranged from 28.66 to 53.37 g.They were fed commercial soft-shelled turtle diet twice a day at five ration levels (starvation,1%,2%,4% and satiation).ANOVA showed that specific growth rate (SGR) and conversion efficiency (K) were significantly affected by the ration level.SGR increased quadratically with increasing ration,and the relationship between SGR for dry matter (SGRd) and ration level (RL) could be expressed as the follow:SGRd=-0.0832RL2+1.0795RL-1.8779(n=25,r2=0.906,F=105.46).The maximum SGR for wet matter,dry matter,protein and energy appeared when ration levels were 6.97%,6.49%,6.08% and 6.34%,respectively.All Ks at 1% ration group were significantly lower than those at 2% and 4%,and Ks for dry matter and energy were lower than the satiation;Ks for dry matter and energy at 2% were significantly higher than those at the satiation.
 OPINION - Endometrial receptivity
作者  Aboubakr M. Elnashar, Gamal I. Aboul-Enein
作者单位  
期刊  Middle East Fertility Society Journal 卷期  Vol. 9, No. 1, 2004 时间  
关键词  Endometrial receptivity, implantation, infertility
摘要   Embryo implantation depends on the quality of the ovum and endometrial receptivity. Endometrial receptivity is a temporally unique sequence of factors that make the endometrium receptive to embryonic implantation. Implantation window is a period during which the endometrium is optimally receptive to implanting blastocyst (D6-10 postovulation). No conclusive evidence of age related histological changes in the endometrium. The biochemical markers of endometrial receptivity include endometrial adhesion molecules (e.g. integrins), endometrial anti-adhesion molecules (e.g. mucin 1), endometrial cytokines, endometrial growth factors, endometrial immune markers and other endometrial markers. Integrins are the best markers of endometrial receptivity. Most interest has been focused on the av β 3 integrin since it appears in endometrial glands and luminal surface on D20-21. Endometrial function test may be the most efficient way to directly assess endometrial receptivity prior to undergoing expensive ART procedures as it can identify unreceptive endometrium. Pinopodes, are morphological markers of endometrial receptivity, which persist for 24 to 48 hours between days 19 and 21 of the cycle. Non invasive assessment of endometrial receptivity includes, high resolution transvaginal ultrasonography (US), three-dimensional US, Doppler US, three-dimensional power Doppler US, magnetic resonance imaging and endometrial tissue blood flow. Four strategies for improving endometrial receptivity: to develop ovarian stimulation protocols that cause a minimum reduction in endometrial receptivity or may even increase it; to avoid the endometrium during stimulated cycles, to improve uterine vascularization and to treat the pathology.
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