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Efficacy of intraovarian autologous platelet-rich plasma administration in women with low ovarian reserve: A systematic review and meta-analysis
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作者 Yasmin Sabina Sa’diah Agung Dewanto Lukman A Chandra 《Asian pacific Journal of Reproduction》 CAS 2024年第2期60-67,共8页
Objective:To conduct a systematic examination and meta-analysis of the most reliable data from experimental studies evaluating the efficacy of autologous platelet-rich plasma(PRP)on low ovarian reserve.Methods:A compr... Objective:To conduct a systematic examination and meta-analysis of the most reliable data from experimental studies evaluating the efficacy of autologous platelet-rich plasma(PRP)on low ovarian reserve.Methods:A comprehensive search was performed utilizing pertinent search terms across electronic databases,including PubMed,Cochrane,and Google Scholar.We included studies that assigned infertile women with low ovarian reserve in experimental studies.Ovarian reserve parameters were measured before and after PRP injection into ovaries.The data of each study was retrieved and subsequently compiled.Results:Of 301 articles collected and reviewed,six studies were finally included in the meta-analysis.Following PRP injection,infertile women showed a non-significant increase in anti-Mullerian hormone(AMH)level(MD=0.10;95%CI-0.04,0.23),a significant increase in antral follicular count(AFC)(MD=1.88;95%CI 0.47,3.29),and a non-significant reduction in follicle-stimulating hormone(FSH)level(MD=-0.22;95%CI-8.32,7.87).Conclusions:Autologous PRP may increase AFC,but not AMH.Although it is found beneficial in enhancing ovarian reserve(AFC),further research with strong evidence is still required. 展开更多
关键词 Platelet-rich plasma Low ovarian reserve Ovarian rejuvenation
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Spatiotemporal variations of ecosystem services and driving factors in the Tianchi Bogda Peak Natural Reserve of Xinjiang,China
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作者 ZHU Haiqiang WANG Jinlong +2 位作者 TANG Junhu DING Zhaolong GONG Lu 《Journal of Arid Land》 SCIE CSCD 2024年第6期816-833,共18页
Nature reserves play a significant role in providing ecosystem services and are key sites for biodiversity conservation.The Tianchi Bogda Peak Natural Reserve(TBPNR),located in Xinjiang Uygur Autonomous Region,China,i... Nature reserves play a significant role in providing ecosystem services and are key sites for biodiversity conservation.The Tianchi Bogda Peak Natural Reserve(TBPNR),located in Xinjiang Uygur Autonomous Region,China,is an important ecological barrier area in the temperate arid zone.The evaluation of its important ecosystem services is of great significance to improve the management level and ecological protection efficiency of the reserve.In the present study,we assessed the spatiotemporal variations of four ecosystem services(including net primary productivity(NPP),water yield,soil conservation,and habitat quality)in the TBPNR from 2000 to 2020 based on the environmental and social data using the Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model.In addition,the coldspot and hotspot areas of ecosystem services were identified by hotspot analysis,and the trade-off and synergistic relationships between ecosystem services were analyzed using factor analysis in a geographic detector.During the study period,NPP and soil conservation values in the reserve increased by 48.20%and 25.56%,respectively;conversely,water yield decreased by 16.56%,and there was no significant change in habitat quality.Spatially,both NPP and habitat quality values were higher in the northern part and lower in the southern part,whereas water yield showed an opposite trend.Correlation analysis revealed that NPP showed a synergistic relationship with habitat quality and soil conservation,and exhibited a trade-off relationship with water yield.Water yield and habitat quality also had a trade-off relationship.NPP and habitat quality were affected by annual average temperature and Normalized Difference Vegetation Index(NDVI),respectively,while water yield and soil conservation were more affected by digital elevation model(DEM).Therefore,attention should be paid to the spatial distribution and dynamics of trade-off and synergistic relationships between ecosystem services in future ecological management.The findings of the present study provide a reference that could facilitate the sustainable utilization of ecosystem services in the typical fragile areas of Northwest China. 展开更多
关键词 net primary productivity(NPP) water yield soil conservation habitat quality Integrated Valuation of Ecosystem Services and Trade-offs(InVEST)model geographic detector Tianchi Bogda Peak Natural Reserve
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Ovarian function in patients with systemic lupus erythematosus:Pathogenesis,drug application and prospective therapies
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作者 Min Xu Li-Li Tian +3 位作者 Xiao-Liu Li Cheng Bao Hai-Wei Zhang Hong-Wei Chen 《World Journal of Experimental Medicine》 2024年第2期29-34,共6页
Systemic lupus erythematosus(SLE)is a chronic autoimmune disease in which multiple organs are damaged that prevails in fertile women.Currently,glucocorticoids and immunosuppressants are widely used to treat SLE patien... Systemic lupus erythematosus(SLE)is a chronic autoimmune disease in which multiple organs are damaged that prevails in fertile women.Currently,glucocorticoids and immunosuppressants are widely used to treat SLE patients.However,ovarian dysfunction occurs following the use of these drugs in women with SLE.Here,we summarize recent progress in terms of understanding ovarian injury,the effects of drug application and strategies to improve ovarian function in women with SLE.This review could be helpful to precisely cure SLE in women desiring to have offspring. 展开更多
关键词 systemic lupus erythematosus Ovarian reserve Ovarian insufficiency Mesenchymal stem cells FERTILITY Autoimmune disease
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Dynamic channel reservation scheme based on priorities in LEO satellite systems 被引量:8
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作者 Jian Zhou Xiaoguo Ye +2 位作者 Yong Pan Fu Xiao Lijuan Sun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2015年第1期1-9,共9页
According to low earth orbit(LEO) satellite systems with users of different levels, a dynamic channel reservation scheme based on priorities is proposed. Dynamic calculation of the thresholds for reserved channels i... According to low earth orbit(LEO) satellite systems with users of different levels, a dynamic channel reservation scheme based on priorities is proposed. Dynamic calculation of the thresholds for reserved channels is the key of this strategy. In order to obtain the optimal thresholds, the traffic is predicted based on the high-speed deterministic movement property of LEO satellites firstly. Then, a channel allocation model based on Markov is established. Finally, the solution of the model is obtained based on the genetic algorithm. Without user location, this strategy effectively reduces handover failures and improves channel utilization by adjusting dynamically the thresholds according to traffic conditions. The simulation results show that the system's overall quality of service can be improved by this strategy. 展开更多
关键词 dynamic channel reservation PRIORITY HANDOVER different level user low earth orbit(LEO)
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A Novel Peak-to-Average Power Ratio Reduction Scheme via Tone Reservation in OFDM Systems 被引量:1
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作者 Jurong Bai Yong Li +2 位作者 Wei Cheng Huimin Du Yanben Wang 《China Communications》 SCIE CSCD 2017年第11期279-290,共12页
In this paper, a novel signal-to-clipping noise ratio and least squares approximation tone reservation scheme(SCR-LSA TR) is proposed to reduce the peak-to-average power ratio for orthogonal frequency division multipl... In this paper, a novel signal-to-clipping noise ratio and least squares approximation tone reservation scheme(SCR-LSA TR) is proposed to reduce the peak-to-average power ratio for orthogonal frequency division multiplexing systems. During the SCR procedure, only the element with the maximal amplitude is picked for processing, which not only decreases the algorithm complexity, but also helps to overcome the BER deterioration. With the LSA method, the amplitude of the peak-cancelling signals can approximate to that of the original clipping noise as much as possible. Through the combination of the optimization factor in the LSA method, the classic SCR method can achieve better PAPR reduction with faster convergence. Simulation results show that the proposed SCR-LSA TR scheme has less in-band distortion and smaller out-of-band spectral radiation. The BER of the proposed scheme shows a better performance especially under the 16-QAM over the additive white Gaussian noise channel. 展开更多
关键词 orthogonal frequency division multiplexing peak-to-average power ratio tone reservation signal to clipping noise ratio
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Reservation-based dynamic admission control scheme for wideband code division multiple access systems
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作者 A.Y.Al-nahari S.A.El-Dolil +1 位作者 M.I.Dessouky F.E.Abd El-Samie 《Journal of Central South University》 SCIE EI CAS 2012年第2期393-401,共9页
Call admission control (CAC) and resource reservation (RR) for mobile communication are two important factors that guarantee system efficiency and quality of service (QoS) required for different services in a very sca... Call admission control (CAC) and resource reservation (RR) for mobile communication are two important factors that guarantee system efficiency and quality of service (QoS) required for different services in a very scarce resource as the radio spectrum. A new scheme was proposed which extends the concepts of resource sharing and reservations for wideband code division multiple access (WCDMA) systems with a unique feature of soft capacity. Voice and data traffic were considered. The traffic is further classified into handoff and new requests. The reservation thresholds were dynamically adjusted according to the traffic pattern and mobility prediction in order to achieve the maximum channel utilization, while guaranteeing different QoS constraints. The performance of proposed scheme was evaluated using Markov models. New call blocking probability, handoff call dropping probability, and channel utilization were used as benchmarks for the proposed scheme. 展开更多
关键词 admission control resource reservation wideband code division multiple access resource utilization
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Provision of Fertility Preservation for Young Women with Early-Stage Breast Cancer
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作者 Rosliza Shafie Danielle Elizabeth Robson +1 位作者 Dinithi Samarawickrama William Ledger 《Advances in Reproductive Sciences》 CAS 2023年第1期23-35,共13页
Breast cancer is the most common cancer in women worldwide, constituting 25% of all cancer diagnoses. Even though it is only affecting 4% - 6% of women under the age of 40, it remains the most... Breast cancer is the most common cancer in women worldwide, constituting 25% of all cancer diagnoses. Even though it is only affecting 4% - 6% of women under the age of 40, it remains the most common malignancy among younger patients. Advancement in the treatment and earlier detection gives excellent 5 years of survival. However, the standard treatment that comprises surgical-chemo radiation therapy or hormonal treatment often results in an increased incidence of treatment-induced infertility. Therefore, adding fertility preservation to primary cancer treatment may offer the best opportunity for future fertility. However, despite advancements in Assisted Reproductive Technology (ART), the uptake of fertility services in this group remains low. In this review, we highlighted the effect of all breast cancer treatments on women’s fertility, the effectiveness and safety of ART in breast cancer patients as well as the safety of pregnancy in breast cancer survivors. Our aim is to improve awareness of fertility preservation for breast cancer to ensure all women diagnosed with breast cancer have multidisciplinary approaches with early referral to fertility specialists to discuss regarding potential risks and benefits of fertility preservation to improve the uptake of fertility preservation among this group of patients. 展开更多
关键词 Fertility Preservation Ovarian Reserve Young Women Early-Stage Breast Cancer
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Electronic Reserves System-基于Web的电子教学参考文献服务系统 被引量:26
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作者 唐承秀 《图书馆工作与研究》 CSSCI 北大核心 2004年第1期50-52,共3页
网络技术的发展使传统的教学参考书服务正在走向数字化 ,这种全新的服务方式将会使高校师生得益匪浅。鉴于我国高校图书馆界正积极着手开展此项服务 ,本文参考了北美目前发展比较成熟的电子教学参考文献服务系统 ,对其系统模式及功能特... 网络技术的发展使传统的教学参考书服务正在走向数字化 ,这种全新的服务方式将会使高校师生得益匪浅。鉴于我国高校图书馆界正积极着手开展此项服务 ,本文参考了北美目前发展比较成熟的电子教学参考文献服务系统 ,对其系统模式及功能特点进行了分析 ,旨在为我国高校图书馆开展此项工作提供借鉴和参考。 展开更多
关键词 Electronic RESERVES system 图书馆 教学参考书 电子文献 文献服务 网络服务
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High quality repair of osteochondral defects in rats using the extracellular matrix of antler stem cells 被引量:1
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作者 Yu-Su Wang Wen-Hui Chu +4 位作者 Jing-Jie Zhai Wen-Ying Wang Zhong-Mei He Quan-Min Zhao Chun-Yi Li 《World Journal of Stem Cells》 SCIE 2024年第2期176-190,共15页
BACKGROUND Cartilage defects are some of the most common causes of arthritis.Cartilage lesions caused by inflammation,trauma or degenerative disease normally result in osteochondral defects.Previous studies have shown... BACKGROUND Cartilage defects are some of the most common causes of arthritis.Cartilage lesions caused by inflammation,trauma or degenerative disease normally result in osteochondral defects.Previous studies have shown that decellularized extracellular matrix(ECM)derived from autologous,allogenic,or xenogeneic mesenchymal stromal cells(MSCs)can effectively restore osteochondral integrity.AIM To determine whether the decellularized ECM of antler reserve mesenchymal cells(RMCs),a xenogeneic material from antler stem cells,is superior to the currently available treatments for osteochondral defects.METHODS We isolated the RMCs from a 60-d-old sika deer antler and cultured them in vitro to 70%confluence;50 mg/mL L-ascorbic acid was then added to the medium to stimulate ECM deposition.Decellularized sheets of adipocyte-derived MSCs(aMSCs)and antlerogenic periosteal cells(another type of antler stem cells)were used as the controls.Three weeks after ascorbic acid stimulation,the ECM sheets were harvested and applied to the osteochondral defects in rat knee joints.RESULTS The defects were successfully repaired by applying the ECM-sheets.The highest quality of repair was achieved in the RMC-ECM group both in vitro(including cell attachment and proliferation),and in vivo(including the simultaneous regeneration of well-vascularized subchondral bone and avascular articular hyaline cartilage integrated with surrounding native tissues).Notably,the antler-stem-cell-derived ECM(xenogeneic)performed better than the aMSC-ECM(allogenic),while the ECM of the active antler stem cells was superior to that of the quiescent antler stem cells.CONCLUSION Decellularized xenogeneic ECM derived from the antler stem cell,particularly the active form(RMC-ECM),can achieve high quality repair/reconstruction of osteochondral defects,suggesting that selection of decellularized ECM for such repair should be focused more on bioactivity rather than kinship. 展开更多
关键词 Osteochondral defect repair Mesenchymal stem cells Extracellular matrix DECELLULARIZATION Antler stem cells Reserve mesenchymal cells Xenogeneic
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Preservation of Parotid Masseter Fascia in Preventing Frey's Syndrome 被引量:4
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作者 张园 杨建荣 《Journal of Nanjing Medical University》 2004年第6期312-314,共3页
Objective: To compare the functional outcomes of patients who had parotid masseter fascia reserved and unreserved flap elevating scheme in parotidectomy, especially the morbidity of Frey's syndrome. Methods: Twent... Objective: To compare the functional outcomes of patients who had parotid masseter fascia reserved and unreserved flap elevating scheme in parotidectomy, especially the morbidity of Frey's syndrome. Methods: Twenty-three patients (group A) had parotid masseter fascia reserved in the parotidectomy, 32 patients (group B) had parotid masseter fascia unreserved in the operation. Compare the morbidity of gustatory sweating syndrome of the two groups. Results: Follow-up after 6 months to 2.5 years, gustatory sweating syndrome occurred in 4 patients of group A (17%), 17 patients in group B (57%). Conclusion: Reservation technic of the parotid masseter fascial in parotidectomy could prevent regeneration of parasympathetic nerve and thus prevent Frey's syndrome post-operation. 展开更多
关键词 reserve parotid masseter fascia Frey's syndrome gustatory sweating syndrome auriculotemporal nerve syndrome
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Effects of Restoration and Reservation of Xi'an Qujiang Pond Ruins Parks on Urban Landscape 被引量:1
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作者 张韵 马贝娟 《Journal of Landscape Research》 2010年第9期65-67,共3页
This paper had described the influence of restoration and reservation of Xi'an Qujiang Pond Ruins Park on urban landscape with an emphasis,proposed to promote urban landscape development by making use of cultural ... This paper had described the influence of restoration and reservation of Xi'an Qujiang Pond Ruins Park on urban landscape with an emphasis,proposed to promote urban landscape development by making use of cultural ruins. It analyzed the good and bad effects of Xi'an Qujiang Pond Ruins Park on urban landscape and concluded that cultural ruins should be used to shape new outlook of urban landscape,so as to discuss the momentous significance of cultural ruins in urban landscape. 展开更多
关键词 CULTURAL ruins PARK RESTORATION reservation
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Study on Spatial and Temporal Distribution Characteristics of Wind Energy Resource and Preservation in Central and West Hexi Corridor 被引量:3
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作者 郭良才 李红英 +2 位作者 于海跃 丑伟 相吉 《Agricultural Science & Technology》 CAS 2011年第3期451-455,共5页
[Objective] The aim was to explore the spatial and temporal distribution characteristics of wind energy resource and preservation in central and west area of Hexi Corridor. [Method] By dint of the wind speed data from... [Objective] The aim was to explore the spatial and temporal distribution characteristics of wind energy resource and preservation in central and west area of Hexi Corridor. [Method] By dint of the wind speed data from 1955 to 2007 in ten meteorological observation station in central and west area of Hexi Corridor,and special wind tower fine data from January to December in 2007,the distribution and reserves of the region's wind energy resources were studied. [Result] The results showed that environmental wind speed was relatively stable in central and west Hexi Corridor. There were no distinct changes in climate characteristics distribution. There were regional differences in the distribution of wind energy,and there was a large numerical area of wind energy in Gazhou County and Yumen City; Wind energy in the region generally was higher. The wind energy density was above 100 w/m2 in the 10 m layer,around 140 w/m2 in most places,and was more than 200 w/m2 in the large number area. The wind grew in vertical direction along with the linear growth of height. Each 10 m high wind increased to 15 w/m2 averagely,50m layer wind energy was greater than the general 240 w/m2 and there were obvious changes on daily and annual with wind energy in central and west area of Hexi Corridor. The duration from March to May was a wind energy-intensive stage,10m height from the ground in the wind around 10:00 in low-value. After growing from 11:00,it met the day largest number at 18:00,and then reduced gradually. Effective wind speed hours in the region in general were more than 6 200 h,and the value in the large areas was close to 7 600 h. [Conclusion] The study laid basis for the development and application of wind energy in central and west area of Hexi Corridor. 展开更多
关键词 Hexi Corridor Wind energy density RESERVES Effective speed
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Peat properties of a tropical forest reserve adjacent to a fire-break canal
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作者 Dayang Nur Sakinah Musa Mohd Zahirasri Mohd Tohir +3 位作者 Xinyan Huang Luqman Chuah Abdullah Mohamad Syazaruddin Md Said Muhammad Firdaus Sulaiman 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期155-167,共13页
Tropical peat comprises decomposed dead plant material and acts like a sponge to absorb water,making it fully saturated.However,drought periods dry it readily and increases its vulnerability to fire.Peat fires emit gr... Tropical peat comprises decomposed dead plant material and acts like a sponge to absorb water,making it fully saturated.However,drought periods dry it readily and increases its vulnerability to fire.Peat fires emit greenhouse gases and particles contributing to haze,and prevention by constructing fire-break canals to reduce fire spread into forest reserves is crucial.This paper aims to determine peat physical and chemical properties near a fire-break canal at different fire frequency areas.Peat sampling was conducted at two forest reserves in Malaysia which represent low fire frequency and high fire frequency areas.The results show that peat properties were not affected by the construction of a fire-break canal,however lignin and cellulose content increased significantly from the distance of the canal in both areas.The study concluded that fire frequency did not significantly influence peat properties except for porosity.The higher fibre content in the high frequency area did not influence moisture content nor the ability to regain moisture.Thus,fire frequency might contribute differently to changes in physical and chemical properties,hence management efforts to construct fire-break canals and restoration efforts should protect peatlands from further degradation.These findings will benefit future management and planning for forest reserves. 展开更多
关键词 Peat fire Peat properties Fire-break canals Forest reserves
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Effects of excessive body fat on colostrum lipid patterns: overweight/obese vs. normal weight mothers
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作者 Qian Liu Yan Liu +11 位作者 Di Yang Yanpin Liu Yan Liu Weicang Qiao Juncai Hou Yaling Wang Minghui Zhang Kai Yang Xiaofei Fan Ziqi Li Junying Zhao Lijun Chen 《Food Science and Human Wellness》 SCIE CAS CSCD 2024年第6期3708-3717,共10页
Prenatal overweight/obesity(OW/OB)can alter colostrum lipid patterns,thereby affecting the lipid metabolism and even the cognitive and healthy development of infants.However,studies on changes in colostrum lipids in t... Prenatal overweight/obesity(OW/OB)can alter colostrum lipid patterns,thereby affecting the lipid metabolism and even the cognitive and healthy development of infants.However,studies on changes in colostrum lipids in the context of OW/OB are limited,particularly for glycerides and polar lipids.Therefore,this study investigated the infl uence of maternal prenatal weight on colostrum in lipid subclasses and molecular species.The concentration of triacylglycerols(TAGs)in the colostrum of the OW/OB group(35894.43 mg/L)was higher than that of the normal weight(NW)group(26639.20 mg/L),suggesting that colostrum from OW/OB mothers could provide more energy to their infants.Further analysis of the fatty acid composition of TAGs revealed that elevated maternal body weight enhanced the concentration of TAGs containing saturated or n-6 fatty acids and shortened the carbon number of TAGs.Docosahexaenoic acid(DHA)/arachidonic acid(AA)/choline-containing lipids,such as DHA-containing TAGs,AA/DHA-containing phosphatidylethanolamine,and choline-containing phospholipids,were present in higher levels in the colostrum of OW/OB mothers than NW mothers.However,the concentrations of palmitic acid-containing TAGs,linoleic acid-containing TAGs,dihomo-γ-linolenic acid-containing TAGs,and polar lipids and the ratio of TAGs containing n-6 fatty acid/n-3 fatty acid were signifi cantly higher in the colostrum of OW/OB mothers than in that of NW mothers.The fatty acid composition and sphingoid bases of sphingolipids were also altered due to elevated body weight.In conclusion,OW/OB affects colostrum lipids with respect to composition,concentration,and percentage.Although the colostrum of healthy OW/OB mothers can provide suffi cient DHA/AA/choline-containing lipids to their infants,normalization of body weight and fat reserves should be considered as a strategy for highquality human milk lipids. 展开更多
关键词 OVERWEIGHT/OBESITY COLOSTRUM Maternal diet Fat reserves GLYCERIDES PHOSPHOLIPIDS SPHINGOLIPIDS
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Swelling pressure evolution characterization of strong expansive soil considering the influence of reserved expansion deformation
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作者 LI Tianguo KONG Lingwei +1 位作者 GUO Aiguo YAN Junbiao 《Journal of Mountain Science》 SCIE CSCD 2024年第1期252-270,共19页
Numerous engineering cases have demonstrated that the expansive soil channel slope remains susceptible to damage with the implementation of a rigid or closed protective structure. It is common for the protective struc... Numerous engineering cases have demonstrated that the expansive soil channel slope remains susceptible to damage with the implementation of a rigid or closed protective structure. It is common for the protective structure to experience bulging failure due to excessive swelling pressure. To investigate the swelling pressure properties of expansive soil, the constant volume test was employed to study the influence of water content and reserved expansion deformation on the characteristics of swelling pressure in strong expansive soils, and also to explore the evolution mechanism of the swelling pressure. The findings demonstrate that the swelling pressure-time curve can be classified into swelling pressure-time softening and swelling pressure-time stability type. The swelling pressuretime curve of the specimen with low water content is the swelling pressure-time softening type, and the softening level will be weakened with increasing reserved expansion deformation. Besides, the maximum swelling pressure Psmax decreases with increasing water content and reserved expansion deformation, especially for expansion ratio η from 24% to 37%. The reserved deformation has little effect on reducing Psmax when it is beyond 7% of the expansion rate. The specimen with low water content has a more homogeneous structure due to the significant expansion-filling effect, and the fracture and reorganization of the aggregates in the specimens with low water content cause the swelling pressure-time softening behavior. In addition, the proposed swelling pressure-time curve prediction model has a good prediction on the test results. If necessary, a deformation space of about 7% expansion rate is recommended to be reserved in the engineering to reduce the swelling pressure except for keeping a stable water content. 展开更多
关键词 Expansive soil Swelling pressure Reserved expansion deformation Water content
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Effects of Seed Reservation-oriented Cultivation on Seed Quality and Disease and Insect Damages of Maca
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作者 徐天才 康平德 +4 位作者 薛润光 和桂青 陈骏飞 孙恒 胡强 《Agricultural Science & Technology》 CAS 2016年第5期1096-1101,共6页
[Objective] The aim was to explore the effects of cultivation and seed reservation methods on quality and disease/insect damages of maca seed in cold highland areas,providing scientific references for cultivation and ... [Objective] The aim was to explore the effects of cultivation and seed reservation methods on quality and disease/insect damages of maca seed in cold highland areas,providing scientific references for cultivation and seed reservation and planning of maca vareity.[Method] Yellow,purple and black maca were selected and cultivated in the region with an elevation of 3 000 m to be experimental materials and cultivation and seed reservation methods were as follows:maca seed reservation in situ,seed reservation in original soils maca grown after selection of maca balls,and seed reservation in the region with an elevation of 2 700 m after selection of maca ball,seed reservation in greenhouses in the region with an elevation of 2 400 m after selection of maca ball,and growing selected balls in greenhouses and transplanting to the farmlands with an elevation of 2 400 m.[Result] The cultivation and seed reservation methods had significant or extremely significant effects on maca phenological phase;maca in different colors were treated by different cultivation and seed reservation methods,showing insignificant effects on disease and insect damages.[Conclusion] It can be concluded that the selected maca balls stored for 15 d as per the method grown in the region with an elevation of 2 700 m will improve seed quality and reduce disease or insect damages. 展开更多
关键词 MACA Seed reservation from cultivation SEED Disease and pest insect
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Coal-rock gas:Concept,connotation and classification criteria
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作者 LI Guoxin ZHANG Shuichang +11 位作者 HE Haiqing HE Xinxing ZHAO Zhe NIU Xiaobing XIONG Xianyue ZHAO Qun GUO Xujie HOU Yuting ZHANG Lei LIANG Kun DUAN Xiaowen ZHAO Zhenyu 《Petroleum Exploration and Development》 SCIE 2024年第4期897-911,共15页
In recent years,great breakthroughs have been made in the exploration and development of natural gas in deep coal-rock reservoirs in Junggar,Ordos and other basins in China.In view of the inconsistency between the ind... In recent years,great breakthroughs have been made in the exploration and development of natural gas in deep coal-rock reservoirs in Junggar,Ordos and other basins in China.In view of the inconsistency between the industrial and academic circles on this new type of unconventional natural gas,this paper defines the concept of"coal-rock gas"on the basis of previous studies,and systematically analyzes its characteristics of occurrence state,transport and storage form,differential accumulation,and development law.Coal-rock gas,geologically unlike coalbed methane in the traditional sense,occurs in both free and adsorbed states,with free state in abundance.It is generated and stored in the same set of rocks through short distance migration,occasionally with the accumulation from other sources.Moreover,coal rock develops cleat fractures,and the free gas accumulates differentially.The coal-rock gas reservoirs deeper than 2000 m are high in pressure,temperature,gas content,gas saturation,and free-gas content.In terms of development,similar to shale gas and tight gas,coal-rock gas can be exploited by natural formation energy after the reservoirs connectivity is improved artificially,that is,the adsorbed gas is desorbed due to pressure drop after the high-potential free gas is recovered,so that the free gas and adsorbed gas are produced in succession for a long term without water drainage for pressure drop.According to buried depth,coal rank,pressure coefficient,reserves scale,reserves abundance and gas well production,the classification criteria and reserves/resources estimation method of coal-rock gas are presented.It is preliminarily estimated that the coal-rock gas in place deeper than 2000 m in China exceeds 30×10^(12)m^(3),indicating an important strategic resource for the country.The Ordos,Sichuan,Junggar and Bohai Bay basins are favorable areas for large-scale enrichment of coal-rock gas.The paper summarizes the technical and management challenges and points out the research directions,laying a foundation for the management,exploration,and development of coal-rock gas in China. 展开更多
关键词 coal-rock gas coalbed methane adsorbed gas free gas classification criteria reserves estimation method
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Changes in renal function and morphological variations of kidney diseases in rheumatoid arthritis patients
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作者 Yan Tang Yuliya Varavko +1 位作者 Raisa Aringazina Irina Menshikova 《Asian Journal of Urology》 CSCD 2024年第2期304-310,共7页
Objective:Rheumatoid nephropathy is one of the most severe extra-articular manifestations of rheumatoid arthritis(RA)associated with a very unfavorable prognosis.This study aimed to identify changes in renal function ... Objective:Rheumatoid nephropathy is one of the most severe extra-articular manifestations of rheumatoid arthritis(RA)associated with a very unfavorable prognosis.This study aimed to identify changes in renal function and morphological variations of kidney diseases in RA patients.Methods:The study enrolled patients(126 patients)between 18 and 55 years of age with a confirmed active RA of more than 12 months.Each patient underwent the following range of laboratory and instrumental research methods:general clinical analysis of blood and urine,performing urinalysis according to Nechiporenko method;determining daily proteinuria;determining the blood content of glucose,urea,creatinine,uric acid,total bilirubin,liver transaminase level,ionogram,lipidogram,and coagulogram;determining the blood content of rheumatoid factor,anti-streptolysin O,and C-reactive protein;and X-ray of the joints of hands and feet.Renal function was examined by estimating glomerular filtration rate,tubular reabsorption index,and renal functional reserve.For studying the morphological changes in the kidneys under ultrasound examination,renal biopsy was performed in 31 patients with RA with urinary syndrome(proteinuria more than 0.3 g per day and hematuria).Results:Nephropathy in RA is characterized by impaired renal function and manifested by an increased blood creatinine and a decrease in glomerular filtration rate and renal functional reserve.Among morphological variations of nephropathy at RA,mesangial proliferative glomerulonephritis prevails,accounting for 48.4%of patients.Other disorders include the secondary amyloidosis(29.0%of patients),tubulointerstitial nephritis(16.1%),membranous glomerulonephritis(3.2%),and focal-segmental glomerulosclerosis(3.2%).Conclusion:Kidney damage is a common systemic manifestation of RA with a long and active course,a major nephropathy trigger. 展开更多
关键词 Rheumatoid nephropathy Secondaryrenal amyloidosis Mesangial proliferative glomerulonephritis Renal functional reserve
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Finer topographic data improves distribution modeling of Picea crassifolia in the northern Qilian Mountains
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作者 ZHANG Xiang GAO Linlin +3 位作者 LUO Yu YUAN Yiyun MA Baolong DENG Yang 《Journal of Mountain Science》 SCIE CSCD 2024年第10期3306-3317,共12页
The Qilian Mountains, a national key ecological function zone in Western China, play a pivotal role in ecosystem services. However, the distribution of its dominant tree species, Picea crassifolia (Qinghai spruce), ha... The Qilian Mountains, a national key ecological function zone in Western China, play a pivotal role in ecosystem services. However, the distribution of its dominant tree species, Picea crassifolia (Qinghai spruce), has decreased dramatically in the past decades due to climate change and human activity, which may have influenced its ecological functions. To restore its ecological functions, reasonable reforestation is the key measure. Many previous efforts have predicted the potential distribution of Picea crassifolia, which provides guidance on regional reforestation policy. However, all of them were performed at low spatial resolution, thus ignoring the natural characteristics of the patchy distribution of Picea crassifolia. Here, we modeled the distribution of Picea crassifolia with species distribution models at high spatial resolutions. For many models, the area under the receiver operating characteristic curve (AUC) is larger than 0.9, suggesting their excellent precision. The AUC of models at 30 m is higher than that of models at 90 m, and the current potential distribution of Picea crassifolia is more closely aligned with its actual distribution at 30 m, demonstrating that finer data resolution improves model performance. Besides, for models at 90 m resolution, annual precipitation (Bio12) played the paramount influence on the distribution of Picea crassifolia, while the aspect became the most important one at 30 m, indicating the crucial role of finer topographic data in modeling species with patchy distribution. The current distribution of Picea crassifolia was concentrated in the northern and central parts of the study area, and this pattern will be maintained under future scenarios, although some habitat loss in the central parts and gain in the eastern regions is expected owing to increasing temperatures and precipitation. Our findings can guide protective and restoration strategies for the Qilian Mountains, which would benefit regional ecological balance. 展开更多
关键词 Species distribution modeling Picea crassifolia High resolution topographic data Climate change Qilian Mountains Nature Reserve Climate scenarios
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Deferred revascularization in diabetic patient according to combined invasive functional and intravascular imaging data:A case report
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作者 Arif Al Nooryani Wael Aboushokka +1 位作者 Branko Beleslin Biljana Nedeljkovic-Beleslin 《World Journal of Clinical Cases》 SCIE 2024年第13期2269-2274,共6页
BACKGROUND Invasive functional evaluation by fractional flow reserve(FFR)is considered as a gold standard for the evaluation of intermediate coronary stenosis.However,in patients with diabetes due to accelerated progr... BACKGROUND Invasive functional evaluation by fractional flow reserve(FFR)is considered as a gold standard for the evaluation of intermediate coronary stenosis.However,in patients with diabetes due to accelerated progression of atherosclerosis the outcome may be worse even in the presence of negative functional testing.CASE SUMMARY We present a case of 55-year-old male diabetic patient who was admitted for chest pain.Diagnostic coronary angiography disclosed 2 intermediate stenoses of the obtuse marginal branch with no evidence of restenosis on previously implanted stent.Patient undergone invasive functional testing of intermediate lesion with preserved FFR(0.88),low coronary flow reserve(1.2)and very high index of microvascular resistance(84).Due to discrepancy in invasive functional parameters,intravascular imaging with optical coherence tomography showed fibrotic stenoses without signs of thin-sup fibroatheroma.Because of the preserved FFR and no signs of vulnerable plaque,the interventional procedure was deferred and the patient continued with optimal medications.CONCLUSION Combined functional and anatomic imaging of intermediate coronary stenosis in diabetic patients represent comprehensive contemporary decision pathway in the management of the patients. 展开更多
关键词 Fractional flow reserve Coronary flow reserve Index of microvascular resistance Optical coherence tomography Intermediate coronary stenosis Case report
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