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Analysis of High Reproductivity on Wild Yak Bull
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作者 陆仲璘 《中国草食动物》 2005年第z2期199-200,共2页
Sperm concentration of wild yak bull is 2. 13 billion per milliliter. Survival time at 0-4 ℃ is 57hrs. After thawing survival time at 37 ℃ is 12 hrs. Resistance coefficient is 144,000. Abnormal sperm rate and acroso... Sperm concentration of wild yak bull is 2. 13 billion per milliliter. Survival time at 0-4 ℃ is 57hrs. After thawing survival time at 37 ℃ is 12 hrs. Resistance coefficient is 144,000. Abnormal sperm rate and acrosomal integrated rate of post-thawing is 9.17% and 87.53% respectively. Moving viscosity is 1. 169 cp. Total nitrogen is 1 437.7 mg/100 ml. Head of sperm is significantly shorter and end piece is significantly longer than that of domestic yak and yellow cattle. Activity of hyaluronidase is highly stronger than the domestic yak,and the activity of LDH is higher than the domestic yak by 48 %. Hence,the fertility of the wild yak bull is powerful and the artificial inseminated rate with domestic yak and yellow cattle is 88.9% and 71.58% respectively. 展开更多
关键词 reproductivity WILD YAK
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A Study on the Transmission Dynamics of the Omicron Variant of COVID-19 Using Nonlinear Mathematical Models 被引量:1
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作者 S.Dickson S.Padmasekaran +2 位作者 Pushpendra Kumar Kottakkaran Sooppy Nisar Hamidreza Marasi 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第6期2265-2287,共23页
This research examines the transmission dynamics of the Omicron variant of COVID-19 using SEIQIcRVW and SQIRV models,considering the delay in converting susceptible individuals into infected ones.The significant delay... This research examines the transmission dynamics of the Omicron variant of COVID-19 using SEIQIcRVW and SQIRV models,considering the delay in converting susceptible individuals into infected ones.The significant delays eventually resulted in the pandemic’s containment.To ensure the safety of the host population,this concept integrates quarantine and the COVID-19 vaccine.We investigate the stability of the proposed models.The fundamental reproduction number influences stability conditions.According to our findings,asymptomatic cases considerably impact the prevalence of Omicron infection in the community.The real data of the Omicron variant from Chennai,Tamil Nadu,India,is used to validate the outputs. 展开更多
关键词 Omicron local stability reproduction number steady states global stability
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Identification and Expression Profile of a Neuropeptide LFRFamide-Like Gene During Different Stages of Gonadal Development in the Cephalopod Sepia pharaonis
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作者 QIU Jiayin SUN Lianlian +3 位作者 LI Shuang ZHOU Xu CHI Changfeng ZHENG Libing 《Journal of Ocean University of China》 CAS CSCD 2024年第2期499-508,共10页
Neuropeptides are widely distributed in vertebrates and invertebrates,regulating a variety of physiological activities in the organisms,such as metabolism,feeding and reproduction.In this study,to explore the function... Neuropeptides are widely distributed in vertebrates and invertebrates,regulating a variety of physiological activities in the organisms,such as metabolism,feeding and reproduction.In this study,to explore the function of neuropeptide LFRFamide in Sepia pharaonis,the full-length cDNA of LFRFamide-like gene(named SpLFRFL,MG869822.1)was identified with rapid amplification of cDNA ends(RACE)method.The sequence of SpLFRFL was 860 bp in length and encoded 188 amino acids containing 4 different mature peptides:1 copy of PHTPFRFamide,NSLFRFamide,TIFRFamide,and 3 copies of GNLFRFamide.Multiple alignment and phylogenetic analysis results showed that SpLFRFL shared high identity with LFRFamides of Sepia officinalis and Sepiella japonica and had the closest relationship with them.Through quantitative Real-time PCR(qRT-PCR),it was found that the SpLFRFL gene was highly expressed in the optic lobe and brain at three different stages during gonad development in both genders.Moreover,the four mature peptides at a concentration of 0.01μmol L^(−1) could inhibit the protein synthesis in the Chinese hamster ovary cell strain-K1(CHOK1)induced by SpGnRH.These data suggest that SpLFRFL might be involved in the development and reproduction of S.pharaonis.The results can contribute to future studies on neuropeptide evolution and function and benefit the cuttlefish farming. 展开更多
关键词 NEUROPEPTIDE LFRFamide-like CEPHALOPOD CUTTLEFISH Sepia pharaonis development REPRODUCTION
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Photoperiod Mediates the Effects of Temperature and Light Intensity on the Proliferation of Ulva prolifera
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作者 JIANG Jianan YU Yanyan +2 位作者 CHEN Yili LI Yahe XU Nianjun 《Journal of Ocean University of China》 CAS CSCD 2024年第1期255-263,共9页
In order to study the complex effects of photoperiod,temperature,and light intensity on the spore maturation and release number of Ulva prolifera,we cultured thalli segment(2–3 mm)under three different photoperiods(L... In order to study the complex effects of photoperiod,temperature,and light intensity on the spore maturation and release number of Ulva prolifera,we cultured thalli segment(2–3 mm)under three different photoperiods(L:D=12:12,14:10 and 10:14),temperature(15℃(LT),25℃(MT)and 30℃(HT))and light intensity(100,200 and 400μmol m^(−2)s^(−1),noted as LL,ML and HL,respectively)conditions.Then the maturation time,spore release number and chlorophyll fluorescence were analyzed.The results suggested that:1)The spore maturation time was accelerated by higher temperature or higher light intensity from 62 h to 36 h,and changes in day length accelerated the spore maturation to a certain extent as compared with 12:12 light/dark cycle;2)Higher light intensity significantly decreased the chlorophyll fluorescence(Fv′/Fm′,NPQ,rETRmax andα)of the mature reproductive segment under 30℃with 12:12 light/dark cycle.But when in the other photoperiods(10:14 and 14:10 conditions),the inhibitory effects of high light intensity were alleviated significantly;3)The optimum condition for the spore maturation and release was 12:12 light/dark cycle,25℃,400μmol m^(−2)s^(−1),with both shorter and longer photoperiod reducing the spore release number;4)Higher light intensity significantly increased the spore release number under 25℃,but these effects were alleviated by 30℃treatment.This study is the first attempt to elucidate the coincidence effects of photoperiod,temperature and light intensity on the reproduction of Ulva,which would help to reveal the mechanism of the rapid proliferation of green tide. 展开更多
关键词 light intensity MATURATION PHOTOPERIOD REPRODUCTION TEMPERATURE Ulva prolifera
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Dietary supplementation of laminarin improves the reproductive performance of sows and the growth of suckling piglets
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作者 Pengguang Zhang Guoyuan Jiang +6 位作者 Chenghong Ma Yubo Wang Enfa Yan Linjuan He Jianxin Guo Xin Zhang Jingdong Yin 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第1期329-343,共15页
Background Maternal nutrition is essential in keeping a highly efficient production system in the pig industry.Laminarin has been shown to improve antioxidant capacity,reduce the inflammatory response,and favor the ho... Background Maternal nutrition is essential in keeping a highly efficient production system in the pig industry.Laminarin has been shown to improve antioxidant capacity,reduce the inflammatory response,and favor the homeostasis of intestinal microbiota.However,the effect of dietary supplementation of laminarin on the reproductive performance of sows and the growth of suckling offspring remains unknown.Methods A total of 40 Landrace×Yorkshire multiparous sows on d 85 of gestation,similar in age,body weight(BW),parity and reproductive performance,were randomly divided into four dietary treatments with 10 sows per treatment,receiving a control diet(basal pregnancy or lactating diets)and a basal diet supplemented with 0.025%,0.05%and 0.10%laminarin,respectively.The experiment lasted from d 85 of gestation to d 21 of lactation.Results Laminarin supplementation linearly increased number born alive per litter(P=0.03),average daily feed intake(ADFI,P<0.01),and total milk yield of sows during the lactation of 1–21 d(P=0.02).Furthermore,maternal laminarin supplementation increased the average daily gain(ADG)of piglets while tending to reduce the culling and death rate before weaning.In addition,alterations to the composition of colostrum and milk,as well as to serum inflammatory cytokines and immunoglobulins of sows were observed.The fecal microbiota profile of sows supported the improvement of reproductive performance in sows and the growth performance in suckling offspring.Conclusions Dietary supplementation of laminarin during late pregnancy and lactation could significantly improve reproductive performance of sows and growth performance of piglets. 展开更多
关键词 Fecal microbiota LAMINARIN MILK PIGLETS Reproductive performance SOWS
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Tissue distribution of cadmium and its effect on reproduction in Spodoptera exigua
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作者 Honghua Su Menglu Wu +3 位作者 Yong Yang Yan Deng Yizhong Yang Qingming Sun 《Journal of Integrative Agriculture》 SCIE CSCD 2024年第1期195-204,共10页
Vegetable fields are often contaminated by heavy metals,and Spodoptera exigua is a major vegetable pest which is stressed by heavy metals mainly by feeding.In this study,cadmium accumulation in the tissues of S.exigua... Vegetable fields are often contaminated by heavy metals,and Spodoptera exigua is a major vegetable pest which is stressed by heavy metals mainly by feeding.In this study,cadmium accumulation in the tissues of S.exigua exposed to cadmium and its effects on the growth and development of the parents and the offspring were investigated.Under the stress of different concentrations of cadmium(0.2,3.2,and 51.2 mg kg^(-1)),the cadmium content in each tissue of S.exigua increased in a dose-dependent manner.At the larval stage,the highest cadmium accumulation was found in midgut in all three cadmium treatments,but at the adult stage,the highest cadmium content was found in fat body.In addition,the cadmium content in ovaries was much higher than in testes.When F1S.exigua was stressed by cadmium and the F_(2)generation was not fed a cadmium-containing diet,the larval survival,pupation rate,emergence rate and fecundity of the F_(2)generation were significantly reduced in the 51.2 mg kg^(-1)treatment compared to the corresponding F1generation.Even in the F_(2)generation of the 3.2 mg kg^(-1)treatment,the fecundity was significantly lower than in the parental generation.The fecundity of the only-female stressed treatment was significantly lower than that of the only-male stressed treatment at the 3.2 and 51.2 mg kg^(-1)cadmium exposure levels.When only mothers were stressed at the larval stage,the fecundity of the F_(2)generation was significantly lower than that of the F1generation in the 51.2 mg kg^(-1)treatment,and it was also significantly lower than in the 3.2 and 0.2 mg kg^(-1)treatments.The results of our study can provide useful information for forecasting the population increase trends under different heavy metal stress conditions and for the reliable environmental risk assessment of heavy metal pollution. 展开更多
关键词 heavy metal pollution CADMIUM Spodoptera exigua tissue distribution REPRODUCTION
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Patterns and drivers of plant sexual systems in the dry-hot valley region of southwestern China
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作者 Rong Ma Qi Xu +3 位作者 Yongqian Gao Deli Peng Hang Sun Bo Song 《Plant Diversity》 SCIE CAS CSCD 2024年第2期158-168,共11页
Sexual systems play important roles in angiosperm evolution and exhibit substantial variations among different floras. Thus, studying their evolution in a whole flora is crucial for understanding the formation and mai... Sexual systems play important roles in angiosperm evolution and exhibit substantial variations among different floras. Thus, studying their evolution in a whole flora is crucial for understanding the formation and maintenance of plant biodiversity and predicting its responses to environmental change. In this study, we determined the patterns of plant sexual systems and their associations with geographic elements and various life-history traits in dry-hot valley region of southwestern China, an extremely vulnerable ecosystem. Of the 3166 angiosperm species recorded in this area, 74.5% were hermaphroditic,13.5% were monoecious and 12% were dioecious, showing a high incidence of diclinous species. Diclinous species were strongly associated with tropical elements, whereas hermaphroditic species were strongly associated with temperate and cosmopolitan elements. We also found that hermaphroditism was strongly associated with showy floral displays, specialist entomophily, dry fruits and herbaceous plants.Dioecy was strongly associated with inconspicuous, pale-colored flowers, generalist entomophily, fleshy fruits, and woody plants, whereas monoecy was strongly associated with inconspicuous, pale-colored flowers, anemophily, dry fruits, and herbaceous plants. In addition, hermaphroditic species with generalist entomophily tended to flower in the dry season, whereas diclinous species with specialist entomophily tended to flower in the rainy season. However, independent of sexual systems, plants that produce dry fruits tended to flower in the rainy season and set fruits in the dry season, but the opposite pattern was found for fleshy fruit-producing plants. Our results suggest that in the dry-hot valleys, plant sexual systems are associated with geographic elements as well as various life-history traits that are sensitive to environmental change. 展开更多
关键词 Floral traits Fruit type Growth form Pollination system Reproductive phenology
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Correlation of personality with individual reproductive success in shrub-nesting birds depends on their life history style
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作者 Jianchuan Li Wen Zhang +5 位作者 Ningning Sun Yujie Wang Lifang Gao Ran Feng Liqing Fan Bo Du 《Avian Research》 SCIE CSCD 2024年第1期42-49,共8页
Two questions in the research of animal personality—whether there is a correlation between a personality trait and individual reproductive success,and what is the genetic basis underlying a personality trait—remain ... Two questions in the research of animal personality—whether there is a correlation between a personality trait and individual reproductive success,and what is the genetic basis underlying a personality trait—remain unresolved.We addressed these two questions in three shrub-nesting birds,the Azure-winged Magpie(Cyanopica cyanus,AM),White-collared Blackbird(Turdus albocinctus,WB),and Brown-cheeked Laughingthrush(Trochalopteron henrici,BL).The personality type of an individual was first identified according to its response to a territorial intruder.Then,we compared the fleeing distance,breeding parameters,and differential expressed genes(DEGs) in the brain transcriptome between bold and shy breeders.In the three species,bold breeders exhibited more aggressiveness towards an intruder of their territory than did shy breeders.The reproductive success of bold breeders was significantly higher than that of shy breeders in AM but not in WB and BL.The three species shared one DEG,crabp1,which was up-regulated in bold relative to in shy individuals.By regulating the expression of corticotropin-releasing hormone,higher crabp1 gene expression can decrease cellular response to retinoic acid.Therefore,bold individuals are insensitive to external stresses and able to exhibit more aggressiveness to intruders than their shier counterparts.Aggressiveness is beneficial to bold individuals in AM but not in WB and BL because the former could evoke neighbors to make the same response of defending against intruders but the latter could not.Although a personality trait may have the same genetic basis across species,its correlation with reproductive success depends largely on the life history style of a species. 展开更多
关键词 BOLDNESS Life history style PERSONALITY Reproductive success Transcriptome analysis
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Sexual Dimorphism and Female Reproductive Characteristics in the Hainan Water Skink(Tropidophorus hainanus)from Hainan,South China
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作者 Yu DU Xiaming ZHU +2 位作者 Chixian LIN Yuntao YAO Xiang JI 《Asian Herpetological Research》 SCIE CSCD 2024年第1期49-58,共10页
We studied sexual dimorphism in body size and shape and female reproductive characteristics in the Hainan Water Skink(Tropidophorus hainanus)from Hainan,South China.In our sample the largest female and male were 61.1 ... We studied sexual dimorphism in body size and shape and female reproductive characteristics in the Hainan Water Skink(Tropidophorus hainanus)from Hainan,South China.In our sample the largest female and male were 61.1 and 55.2 mm snout-vent length(SVL),respectively.The mean SVL was larger in adult females(52.0 mm)than in adult males(48.3 mm).Juveniles were sexually dimorphic in head length but not in other examined morphological variables.Adult males were longer in head length and shorter in abdomen length and fore-limb length than adult females of the same SVL.Ontogenetic shifts in sexual dimorphism in body shape were evident,as revealed by the fact that morphological differences between the sexes were more pronounced in adults than in juveniles.Females produced a single litter of 3–6 offspring per season from early August to early September.Litter size,litter mass and offspring(neonate)mass were positively related to female SVL.Neonate mass was independent of relative fecundity.From the above findings we draw three main conclusions.First,females are the larger sex in T.hainanus,and sexual dimorphism in body shape is more pronounced in adults than in juveniles.Second,larger female T.hainanus produce more and larger offspring and thus heavier litters than smaller ones.Third,the offspring size-number trade-off does is not evident in T.hainanus. 展开更多
关键词 FECUNDITY morphology offspring size-number trade-off REPRODUCTION SCINCIDAE sexual dimorphism
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Sex-specific facilitation and reproduction of the gynodioecious cushion plant Arenaria polytrichoides on the Himalaya-Hengduan mountains,SW China
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作者 Xufang Chen Yazhou Zhang +3 位作者 Lishen Qian Renyu Zhou Hang Sun Jianguo Chen 《Plant Diversity》 SCIE CAS CSCD 2024年第2期247-255,共9页
When benefiting other beneficiaries,cushion plants may reciprocally receive feedback effects.The feedback effects on different sex morphs,however,remains unclear.In this study,taking the gynodioecious Arenaria polytri... When benefiting other beneficiaries,cushion plants may reciprocally receive feedback effects.The feedback effects on different sex morphs,however,remains unclear.In this study,taking the gynodioecious Arenaria polytrichiodes as a model species,we aimed to assess the sex-specific facilitation intensity of cushion plant by measuring the beneficiary cover ratio,and to assess the potential costs in cushion reproductive functions by measuring the flower and fruit cover ratios.The total beneficiary cover ratio was similar between females and hermaphrodites.Females produced much less flowers but more fruits than hermaphrodites.These results suggested that females and hermaphrodites possess similar facilitation intensity,and female cushion A.polytrichoides may allocate more resources saved from pollen production to seed production,while hermaphrodites possibly allocate more resources to pollen production hence reducing seed production.The surface areas covered by beneficiaries produced less flowers and fruits than areas without beneficiaries.In addition,strong negative correlations between beneficiary cover and flower cover were detected for both females and hermaphrodites,but the correlation strength were similar for these two sex morphs.However,the correlation between beneficiary cover and fruit cover was only significantly negative for females,suggesting that beneficiary plants negatively affect fruit reproduction of females while have neutral effects on hermaphrodites.All the results suggest that to facilitate other beneficiaries can induce reproductive costs on cushion A.polytrichoides,with females possibly suffering greater cost than hermaphrodites.Such differentiation in reproductive costs between sex morphs,in long-term perspective,may imply sex imbalance in population dynamics. 展开更多
关键词 Facilitation intensity Feedback effect Sex-specific facilitation Nurse plant Population dynamics Reproductive function
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Genome-wide SNP markers provided insights into the reproductive strategy and genetic diversity of the green tide causative species Ulva prolifera in China
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作者 Song SUN Weiwei MA +2 位作者 Nan WANG Song FENG Yan SUN 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第2期533-543,共11页
Ulva prolifera is the causative species of the annually occurring large-scale green tides in China since 2007.Its specific biological features on reproductivity strategies,as well as intra-species genetic diversity,ar... Ulva prolifera is the causative species of the annually occurring large-scale green tides in China since 2007.Its specific biological features on reproductivity strategies,as well as intra-species genetic diversity,are still largely unknown,especially at the genome level,despite their importance in understanding the formation and outbreak of massive green tides.In the present study,the restriction site-associated DNA genotyping approach(2b-RAD)was adopted to identify the genome-wide single-nucleotide polymorphisms(SNPs)of 54 individual thalli including samples collected from Subei Shoal in 2019 and Qingdao coast from 2019 to 2021.SNPs genotype results revealed that most of the thalli in 2019 and 2020 were haploid gametophytes,while only half of the thalli were gametophytes in 2021,indicating flexibility in the reproductive strategies for the formation of the green tides among different years and the dominance of asexual and vegetative reproductive mode for the floating period.Besides,population analysis was conducted,and it revealed a very low genetic diversity among samples from Subei Shoal and the Qingdao coast in the same year and a higher divergence among samples in different years.The results showed the efficiency of 2b-RAD in the exploration of SNPs in U.prolifera and provided the first genome-wide scale evidence for the origin of the large-scale green tides on the Qingdao coast.This study improved our understanding of the reproductive strategy and genetic diversity of the green tide causative species and will help further reveal the biological causes of the green tide in China. 展开更多
关键词 green tide Ulva prolifera 2b-RAD single-nucleotide polymorphism(SNP) reproductive strategy genetic diversity
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Engineering of ovarian tissue for ovarian dysfunctions:A review
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作者 Aliya Zhylkybekova Gulbakit KKoshmaganbetova +5 位作者 Myltykbay SRysmakhanov Nurgul Abdullayevna Abenova Nadiar Maratovich Mussin Asset Askerovich Kaliyev Mahdi Mahdipour Amin Tamadon 《Asian pacific Journal of Reproduction》 CAS 2024年第1期3-11,共9页
This review explores tissue engineering as a potential solution for reproductive health issues in women caused by genetic or acquired diseases,such as premature ovarian failure or oophorectomy.The loss of ovarian func... This review explores tissue engineering as a potential solution for reproductive health issues in women caused by genetic or acquired diseases,such as premature ovarian failure or oophorectomy.The loss of ovarian function can lead to infertility,osteoporosis,and cardiovascular disease.Hormone replacement therapy is a common treatment,but it has limitations and risks.The review focuses on two main approaches in tissue engineering:scaffold-based(3D printing,electrospinning,decellularization)and scaffold-free(stem cell transplantation,organoid cultivation).Both approaches show promise in preclinical studies for creating functional ovarian tissue.Challenges include vascularization,innervation,long-term function,and safety.Despite these challenges,tissue engineering offers a potential avenue for restoring fertility and hormone balance in women with ovarian dysfunction. 展开更多
关键词 Female gonads Tissue engineering ESTROGEN Reproductive system
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Knowledge, attitudes, and practices regarding Covid-19 and their relationship with Covid-19 booster vaccination status among women with infertility
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作者 Gita Pratama Mila Maidarti +4 位作者 Kanadi Sumapradja Achmad Kemal Harzif Natasha Talya Kevin Ezekia Irfan Arieqal Hatta Ampri 《Asian pacific Journal of Reproduction》 CAS 2024年第2期68-75,共8页
Objective:To elucidate the relationship among knowledge,attitudes,and practices regarding Covid-19 and their relationship with booster vaccination status among women with infertility.Methods:This questionnaire-based c... Objective:To elucidate the relationship among knowledge,attitudes,and practices regarding Covid-19 and their relationship with booster vaccination status among women with infertility.Methods:This questionnaire-based cross-sectional study was performed online and offline among women with infertility who visited an infertility clinic in Jakarta,Indonesia.We assessed the patient’s knowledge,attitudes,and practices regarding Covid-19 and their relationship with booster vaccination status and sociodemographic profile.Results:A total of 178 subjects participated in this study,and most participants(92.6%)had received booster Covid-19 vaccines.From the questionnaire,74.2%had good knowledge,and 99.4%had good attitudes regarding Covid-19;however,only 57.9%of patients had good practices.A weak positive correlation existed between knowledge and attitudes(r=0.11,P=0.13)and a moderate negative correlation between attitudes and practices(r=-0.44,P=0.56).Participants’knowledge about vaccines and infertility was correlated with booster vaccination status(P=0.04).Academic background(P=0.01)and attitudes(P=0.01)were also correlated with booster vaccination status.The significant determinants of hesitance of receiving Covid-19 booster vaccines were high school education or below(OR=0.08,95%CI 0.02-0.36)and poor practices(OR=0.21,95%CI 0.05-0.95).Conclusions:The majority of the participants had received the Covid-19 booster vaccine and had good knowledge and attitudes but poor practices regarding Covid-19.Most participants had poor knowledge about the relationship between infertility and the Covid-19 vaccine.The general population should be more informed and reminded about practices to prevent Covid-19 and the relationship between vaccination and fertility to increase the number of people who receive Covid-19 booster vaccines. 展开更多
关键词 Covid-19 Booster vaccine INFERTILITY KNOWLEDGE Attitude Practice Human reproduction PANDEMIC
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Attitude and willingness on gamete donation among medical students:An experience from a state university in Sri Lanka
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作者 S.Raguraman K.Muhunthan R.Niroje 《Asian pacific Journal of Reproduction》 CAS 2024年第3期120-125,共6页
Objective:To assess the attitude and willingness of medical students of the Faculty of Medicine,University of Jaffna,regarding gamete donation.Methods:An institutional-based descriptive cross-sectional study was condu... Objective:To assess the attitude and willingness of medical students of the Faculty of Medicine,University of Jaffna,regarding gamete donation.Methods:An institutional-based descriptive cross-sectional study was conducted at the Faculty of Medicine,University of Jaffna,from September 2022 to May 2023 among undergraduate medical students who gave their voluntary participation.A self-administered questionnaire was used as a study instrument to collect data regarding their attitude and willingness toward gamete donation.Results:A total of 345 participants were recruited and their sociodemographic data revealed that 56.8%of the participants were female,62.3%aged between 26 and 30 years,and 92.2%were unmarried.Many of them received information regarding gamete donations during their clinical appointments.Over half(67.8%)of them showed a negative attitude towards gamete donation.Regarding willingness,only 39.7%of participants had a positive approach for being a gamete donor;among them,84.7%preferred anonymous donations.Religion and ethnicity had a significant influence on their attitudes and willingness.In addition,male was also found to be more willing to donate gametes.Conclusions:Most medical students have negative views about gamete donation.Imparting awareness and knowledge of assisted reproductive technology and gamete donation within medical students'sociocultural and ethical backgrounds might facilitate a change in attitude towards gamete donation amongst future medical practitioners. 展开更多
关键词 Medical students Gamete donation Assisted reproductive technology ATTITUDE VIEWPOINT
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The relationship between DNA fragmentation and the intensity of morphologically abnormal human spermatozoa
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作者 Mercedes González-Martínez Pascual Sánchez-Martín +2 位作者 Carmen López-Fernández Stephen D.Johnston Jaime Gosálvez 《Asian pacific Journal of Reproduction》 CAS 2024年第1期22-27,共6页
Objective:To determine the relationship between teratozoospermia and sperm DNA fragmentation(SDF)in the human ejaculate.Methods:This retrospective study included 100 normozoospermic men as a control cohort(abnormal fo... Objective:To determine the relationship between teratozoospermia and sperm DNA fragmentation(SDF)in the human ejaculate.Methods:This retrospective study included 100 normozoospermic men as a control cohort(abnormal forms>14%),210 patients with a high level of abnormal forms(≤4%)and 65 patients presenting with a moderate level of abnormal forms(>4%to≤14%)based on the World Health Organization definitions.Sperm morphology was assessed using bright field microscopy.Sperm DNA fragmentation was assessed using the sperm chromatin dispersion assay.Non-parametric analyses were conducted to examine the relationship between abnormal sperm morphology and sperm DNA fragmentation;receiver operating characteristic(ROC)analyses were conducted to assess sensitivity and specificity of this relationship.Results:A correlation analysis revealed that the higher the proportion of abnormal spermatozoa in the ejaculate,the higher the level of SDF(Spearman's Rho=-0.230;P<0.001).Significant differences in the proportion of SDF were found when all cohorts were compared(P<0.001);these significant differences were also retained when the different cohorts were compared pairwise.ROC analysis showed a moderate but significant predictive value for SDF to differentiate patients with different levels of teratozoospemia.Conclusions:Although analysis of a more continuous range of values for teratozoospermia would help further clarify any causal relationship with SDF,there is clearly a synergistic or coincident affiliation between these variables that needs to be acknowledged by the clinician when interpreting the spermiogram. 展开更多
关键词 TERATOZOOSPERMIA Sperm morphology Sperm DNA fragmentation Male factor Human reproduction Human fertility
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Effect of coenzyme Q10 supplementation on post-vitrification mouse embryo development
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作者 Anisa-Annur S Wan-Hafizah WJ +1 位作者 Nor-Ashikin MNK Muhammad-Zaki R 《Asian pacific Journal of Reproduction》 CAS 2024年第3期126-132,共7页
Objective:To investigate the effects of coenzyme Q10(CoQ10)supplementation on post-vitrification embryo development and gross morphology.Methods:Balb/c mouse embryos were cultured in potassium simplex optimised medium... Objective:To investigate the effects of coenzyme Q10(CoQ10)supplementation on post-vitrification embryo development and gross morphology.Methods:Balb/c mouse embryos were cultured in potassium simplex optimised medium(KSOM)with varying CoQ10 concentrations[0(control),20,40,and 60μM].The most effective CoQ10 concentration(40μM)was selected for subsequent post-vitrification morphology study.Embryos were randomly divided into four groups:Group A(non-vitrified without CoQ10),Group B(non-vitrified with CoQ10),Group C(vitrified without CoQ10),and Group D(vitrified with CoQ10),followed by vitrification at the 8-cell stage.Survival rates and development until the blastocyst stage were evaluated through morphological examinations using ASEBIR's system,distinguishing normal and abnormal embryos.Results:Supplementation of 40μM CoQ10 significantly increased blastocyst formation(95%)compared to the control group(92%),20μM(62%),and 60μM(56%)(P<0.001).Following vitrification,Group D exhibited a significant increase in blastocyst formation(92%)compared to Group C(82%)(P<0.05).Morphological assessments indicated superior embryo quality in Group B over Group D during the cleavage stage,morula,and blastocyst(P<0.05).Conclusions:CoQ10 supplementation exhibits promising potential to enhance preimplantation embryo development,increase blastocyst formation rates,and improve embryo quality post-vitrification.This offers a promising approach to mitigate oxidative stress on embryos,potentially improving overall assisted reproductive technology outcomes. 展开更多
关键词 Coenzyme Q10 ANTIOXIDANT Embryo development VITRIFICATION MORPHOLOGY Assisted reproductive technology
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Analysis of radiation diffusion of COVID-19 driven by social attributes
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作者 年福忠 杨晓晨 师亚勇 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期773-779,共7页
This paper first estimated the infectious capacity of COVID-19 based on the time series evolution data of confirmed cases in multiple countries. Then, a method to infer the cross-regional spread speed of COVID-19 was ... This paper first estimated the infectious capacity of COVID-19 based on the time series evolution data of confirmed cases in multiple countries. Then, a method to infer the cross-regional spread speed of COVID-19 was introduced in this paper, which took the gross domestic product(GDP) of each region as one of the factors that affect the spread speed of COVID-19 and studied the relationship between the GDP and the infection density of each region(China's Mainland, the United States, and EU countries). In addition, the geographic distance between regions was also considered in this method and the effect of geographic distance on the spread speed of COVID-19 was studied. Studies have shown that the probability of mutual infection of these two regions decreases with increasing geographic distance. Therefore, this paper proposed an epidemic disease spread index based on GDP and geographic distance to quantify the spread speed of COVID-19 in a region. The analysis results showed a strong correlation between the epidemic disease spread index in a region and the number of confirmed cases. This finding provides reasonable suggestions for the control of epidemics. Strengthening the control measures in regions with higher epidemic disease spread index can effectively control the spread of epidemics. 展开更多
关键词 COVID-19 basic reproduction number gross domestic product(GDP) geographic distance cross-regional spread
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Two missense STK11 gene variations impaired LKB1/adenosine monophosphate-activated protein kinase signaling in Peutz-Jeghers syndrome
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作者 Jin Liu Si-Cong Zeng +3 位作者 An Wang Hai-Ying Cheng Qian-Jun Zhang Guang-Xiu Lu 《World Journal of Gastrointestinal Oncology》 SCIE 2024年第4期1532-1546,共15页
BACKGROUND Peutz-Jeghers syndrome(PJS)is a rare hereditary neoplastic disorder mainly associated with serine/threonine kinase 11(STK11/LKB1)gene mutations.Preimplantation genetic testing can protect a patient’s offsp... BACKGROUND Peutz-Jeghers syndrome(PJS)is a rare hereditary neoplastic disorder mainly associated with serine/threonine kinase 11(STK11/LKB1)gene mutations.Preimplantation genetic testing can protect a patient’s offspring from mutated genes;however,some variations in this gene have been interpreted as variants of uncertain significance(VUS),which complicate reproductive decision-making in genetic counseling.AIM To identify the pathogenicity of two missense variants and provide clinical guidance.METHODS Whole exome gene sequencing and Sanger sequencing were performed on the peripheral blood of patients with PJS treated at the Reproductive and Genetic Hospital of Citic-Xiangya.Software was employed to predict the protein structure,conservation,and pathogenicity of the two missense variation sites in patients with PJS.Additionally,plasmids were constructed and transfected into HeLa cells to observe cell growth.The differences in signal pathway expression between the variant group and the wild-type group were compared using western blot and immunohistochemistry.Statistical analysis was performed using one-way analysis of variance.P<0.05 was considered statistically significant.RESULTS We identified two missense STK11 gene VUS[c.889A>G(p.Arg297Gly)and c.733C>T(p.Leu245Phe)]in 9 unrelated PJS families who were seeking reproductive assistance.The two missense VUS were located in the catalytic domain of serine/threonine kinase,which is a key structure of the liver kinase B1(LKB1)protein.In vitro experiments showed that the phosphorylation levels of adenosine monophosphate-activated protein kinase(AMPK)at Thr172 and LKB1 at Ser428 were significantly higher in transfected variation-type cells than in wild-type cells.In addition,the two missense STK11 variants promoted the proliferation of HeLa cells.Subsequent immunohistochemical analysis showed that phosphorylated-AMPK(Thr172)expression was significantly lower in gastric,colonic,and uterine polyps from PJS patients with missense variations than in non-PJS patients.Our findings indicate that these two missense STK11 variants are likely pathogenic and inactivate the STK11 gene,causing it to lose its function of regulating downstream phosphorylated-AMPK(Thr172),which may lead to the development of PJS.The identification of the pathogenic mutations in these two clinically characterized PJS patients has been helpful in guiding them toward the most appropriate mode of pregnancy assistance.CONCLUSION These two missense variants can be interpreted as likely pathogenic variants that mediated the onset of PJS in the two patients.These findings not only offer insights for clinical decision-making,but also serve as a foundation for further research and reanalysis of missense VUS in rare diseases. 展开更多
关键词 MISSENSE STK11 Peutz-Jeghers syndrome Rare disease Genetic counseling Assisted reproductive technique
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Characteristics of Infertile Clientele Attending a Public in Vitro Fertilization Clinic: Appraising Priorities in a Low-Income Country
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作者 Gbolahan O. Obajimi Olugbenga O. Saanu +2 位作者 Ayodeji S. Adeyanju Ademola S. Olutoye Mofiyinfoluwa M. Adeyeye 《Open Journal of Epidemiology》 2024年第2期343-352,共10页
Introduction: Infertilityaffects one in six couples, and it is an important public health issue largely due to thepervasive effects on the emotional and psychological wellbeing of affected couples. In many developing ... Introduction: Infertilityaffects one in six couples, and it is an important public health issue largely due to thepervasive effects on the emotional and psychological wellbeing of affected couples. In many developing nations emphasis is placed on childbirth and inability to fulfill this role can be very distressing. There is an unmet need for assisted reproductive technology (ART) in many developing countries and where facilities exist, they are mostly privately owned, expensive and concentrated in urban areas. To bridge this gap, public fertility clinics have been established to provide subsidized care. Evaluating the characteristics and peculiarities of clientele presenting at these public facilities will aid planning and prioritization of care. Methodology: A descriptive retrospective study of 116 infertile patients presenting to the fertility clinic of the University College Hospital, Ibadan, Nigeria from inception on the 14<sup>th</sup> of February 2019 and 31<sup>st</sup> of December 2022.Data was analyzed using the Statical Package for Social Sciences (IBM, SPSS, New York) version 23. Descriptive statistics were used to summarize the results which were presented with the aid of bar charts and frequency tables. Result: The mean age of the patients was 40.70 ± 6.62 years. Post-menopausal patients accounted for about one-fifth of the study population while 80.2% (93 women) were older than 35 years. The mean duration of infertility was 9.39 ± 6.11years and nine patients (7.8%) had a duration greater than 2 decades. Secondary infertility occurred in 67.2% of the women. Twenty-nine women (25%) had undergone myomectomy prior to presentation. Hypertension (11.2%) was the most prevalent comorbidity. Nineteen patients (16.4%) had used contraceptives in the past with the male condom (36.8%)being the most preponderant. Sixty-seven patients had experienced pregnancy losses before 28 weeks of gestation while just 16 patients (13.8%) had undergone ART, and none was successful. Conclusion: Secondary infertility was the prevalent type of infertility and may not be unconnected with the low contraceptive usage and high risk of sexually transmitted infection. Late presentation coupled with a large proportion of post-menopausal clientele suggests delayed health-seeking behavior most probably due to the prohibitive cost of ART. The need to streamline services offered in public fertility clinics is paramount in low-income countries grappling with scarce resources. A pragmatic approach will involve the provision of low-cost ART, while enhancing gamete donation programs through the implementation of gamete sharing policies. This will invariably bridge the unmet need and skewed access to ART in developing countries. 展开更多
关键词 INFERTILITY Assisted Reproductive Technology LOW-INCOME Priorities.
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Copyright Authorization Statement
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《Meteorological and Environmental Research》 2024年第1期86-86,共1页
Should the article be accepted and published by Meteorological and Environmental Research,the author hereby grants exclusively to the editorial department of Meteorological and Environmental Research the digital repro... Should the article be accepted and published by Meteorological and Environmental Research,the author hereby grants exclusively to the editorial department of Meteorological and Environmental Research the digital reproduction,distribution,compilation and information network transmission rights. 展开更多
关键词 EDITORIAL REPRODUCTION DEPARTMENT
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