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101.
In this study, the effects of abrupt temperature change on the hatching success and larval survival of eggs, yolk-sac larvae (YSL) and larvae above nest (LAN), for both largemouth bass Micropterus salmoides and smallmouth bass Micropterus dolomieu were quantified. Temperature had a significant effect on hatching success and time to 50% mortality, with large heat shocks causing accelerated mortality. The temperature changes shown to influence survival of all life stages, however, were beyond what is typically experienced in the wild. Micropterus salmoides had greater egg hatching success rates and increased survival rates at YSL and LAN stages, relative to M. dolomieu. Additionally, egg hatching success and survival of LAN varied across nests within the study. These findings suggest that temperature alone may not account for variations in year-class strength and may emphasize the need for protection of the nest-guarding male Micropterus spp. to ensure recruitment.  相似文献   
102.
Zhang H  Wang J  Yi B  Zhao Y  Liu Y  Zhang K  Cai X  Sun J  Huang L  Liao Q 《Gene》2012,495(2):183-188
We investigated the relationship between BsmI/ApaI polymorphisms in vitamin D receptor gene and diabetic nephropathy in a Han Chinese population. PCR-restriction fragment length polymorphism was used to test the genotype and allele frequency of BsmI and ApaI polymorphisms in 304 patients with type 2 diabetes mellitus (DM group) and 100 control individuals (ND group). The DM group was further divided into DN0 (no diabetic nephropathy), DN1 (diabetes with small amount of albuminuria), DN2 (diabetes with large amount of albuminuria), L/NDN (late-onset DN after 5 years/no DN over the whole follow-up period of 5 years) and EDN (early-onset diabetic nephropathy occurring within first year) subgroup. We found that (1) genotype and allele frequency of BsmI polymorphism had significant difference between DM and ND group; BB+Bb genotype and B allele frequency were significantly higher in DN2 group than in ND and DN0 group; the ApaI polymorphism and allele frequency did not show any difference between DM and ND group; (2) BsmI BB+Bb genotype and B allele frequency were significantly higher in EDN group than in L/NDN group; (3) among patients with nephropathy, albumin excretion rate (AER) in 24-hour urine was significantly higher in those with BB+Bb phenotype than in those with bb phenotype (P<0.01), (4) unconditional logistic regression analysis showed that BsmI BB+Bb genotype was not only correlated with type 2 diabetic nephropathy, but also correlated with early-onset type 2 diabetic nephropathy. We conclude that the allele B (BB or Bb genotype) in vitamin D receptor gene is correlated with large amount albuminuria in the Han Chinese population with type 2 diabetes, and is probably a risk factor for early-onset diabetic nephropathy.  相似文献   
103.
doi: 10.1111/j.1741‐2358.2011.00555.x Nutritional status and oral status of the elderly with dementia: a 2‐year study Objectives: To determine the relationship between denture wearing and nutritional status in the elderly with dementia. Background: There could be a correlation between nutrition, oral health, dietary habits, patients’ satisfaction, and their socio‐economic status in the elderly, and the relationship between compromised oral status and nutritional status in the elderly with dementia. Subjects and methods: A 2‐year follow‐up study of 63 elderly Japanese women with and without dentures from a nursing home was undertaken to investigate their oral, physical and mental, and nutritional status. Results: Each item for 2006 and 2008 in this study showed no significant difference between 2006 and 2008, except the calories/day. The elderly with dementia without complete dentures during the 2 years of the study only significantly decreased the mean of the calories/day. Conclusion: The calories/day of the elderly with dementia without dentures decreased after 2 years. Denture wearing for the elderly with dementia could be necessary to maintain a satisfactory intake of calories.  相似文献   
104.
为进一步了解中华绒螯蟹(Eriocheir sinensis)2龄雄体在池塘养殖条件下的生长发育规律,本研究采用养殖实验、活体解剖和显微观察方法,首先研究了池塘养殖过程中二龄雄体的生长、性腺指数(GSI)、肝胰腺指数(HSI)和第二性征(主要包括大螯绒毛长度及其覆盖比例)的变化情况,并探讨了这些指标间的相关性,其次,对成熟雄体的生殖系统外观和组成进行了拍照和描述.结果显示:(1)池塘养殖条件下中华绒螯蟹2龄雄体的体重、甲壳长、甲壳宽和体厚增长主要发生在3~8月,其中4~5月间的增重率和特定增长率最高,9~12月间的体重和形态学参数增长均不显著;肥满度总体上呈先下降后上升的趋势.(2)2龄雄体池塘养殖早期性腺发育较慢,3~5月肉眼很难发现,6月份生精区已经清晰可见,7~11月份性腺指数显著增加,7月份部分个体储精囊中已有精荚,8月份副性腺体积开始迅速增加,整体上,肝胰腺指数(HSI)和性腺指数(GSI)呈显著负相关,而性腺指数(GSI)与生殖蜕壳前的雄体体重及月份均呈显著正相关.(3)2龄雄体的大螯绒毛长度及其内侧绒毛覆盖比例在4~8月呈显著增长趋势,其余月份增加不显著,绒毛长度与覆盖比例、绒毛长度与体重、绒毛覆盖比例与体重、绒毛长度与性腺指数、绒毛覆盖比例与性腺指数都呈显著正相关.(4)2龄成熟雄体的生殖系统由体内和体外两大部分构成,体内部分主要包括精巢、输精管(分为前、中、后三个部分)、副性腺和射精管,输精管后端储存着大量精荚,体外部分主要由阴茎和交接器组成.综上,池塘养殖中华绒螯蟹2龄雄体的生长、性腺发育与其第二性征关系密切,雄体生殖系统组成复杂,今后需要深入研究雄体的性腺发育规律和分期.  相似文献   
105.
This article presents a fossil diatom-based, semi-quantitative reconstruction of water level fluctuations for Lake Baringo over the past 200 years as a consequence of climatic variations. A 285 cm long sediment core sample was collected using a Rod-Operated Single-drive Stationary Piston corer. Lake level was inferred using indices based on the proportion of planktonic to benthic diatom taxa (P/B ratio). The sediment archive presented distinct zones dominated by planktonic and benthic diatom flora. An initial transgression in the early 19th century was characterised as a shallow water environment dominated by planktonic Aulacoseira spp. This was a response to extreme drought during the late 18th to early 19th century. Mid-19th century was defined by a high lake stand. The late 19th to early 20th centuries experienced low water level following the widely documented aridity at the time. The mid-20th century was marked by a spectacular rise in water level that coincided with remarkably wet years during the early 1960s and late 1970s. The first decade of the 21st century witnessed widespread changes in water level. The proxy records show that lake ramping and drawdown over the years follow approximately 50-year climatic cycles.  相似文献   
106.
BackgroundForecast of disease burden in lung cancer is an important health agenda. One of the main challenges is to predict the evolution of trends in disability-adjusted life year (DALY) of lung cancer so as to anticipate the future burden and to coordinate the supply of sufficient health services and care.MethodsUsing 2004–2013 cancer registry data in Guangzhou, we fitted Bayesian age-period-cohort models with age, period, and cohort effects to analyze trends of lung cancer among women, and then made forecast for DALY of lung cancer until 2030.ResultsDuring 2004–2013, there was an annual average of 10,582 DALYs for lung cancer (15.84% of total DALY). In 2014–2030, DALY is expected to reach 234,752 person-years for lung cancer (12.25% of total DALY), with an annual mean of 13,809 DALYs. Lung cancer crude DALY rate is projected to rise steadily from 257.56 (95% uncertainty interval: 165.97–361.22) in 2014 to 316.99 (219.96–419.41) per 100,000 women in 2030, and the rise is mainly seen in 45–64 years age group. Lung cancer DALY rate remains the highest in the 65–89 years age group.ConclusionsWomen at 65–89 years carry the highest lung cancer burden among other age groups in Guangzhou. The DALY rate of lung cancer is projected to increase most precipitously for the 45–64 years age group. This indicates that concerted efforts are needed to develop adequate cancer services, and to reassess health resources for control and care of lung cancer in these populations.  相似文献   
107.
Large-scale features of the spatial arrangement of protein-coding segments (PCS) are investigated by means of the inter-PCS spacers' size distributions, which have been found to follow power-laws. Linearity in double-logarithmic scale extends to several orders of magnitude in the genomes of organisms as disparate as mammals, insects and plants. This feature is also present in the most compact eukaryotic genomes and in half of the examined bacteria, despite their very limited non-coding space. We have tried to determine the sequence of events in the course of genomes' evolution which may account for the formation of the observed size distributions. The proposed mechanism essentially includes two types of events: (i) segmental duplications (and possibly paleopolyploidy), and (ii) the subsequent loss of most of the duplicated genes. It is shown by computer simulations that the formulated scenario generates power-law-like inter-PCS spacers' size distributions, which remain robust for a variety of parameter choices, even if insertion of external sequences, such as viruses or proliferating retroelements is included. Moreover, power-laws are preserved after most of the non-coding DNA has been removed, thus explaining the finding of this pattern in genomes as compact as that of Takifugu rubripes.  相似文献   
108.
We investigated the synthesis of dimethyl ether (DME) from biomass synthesis gas using a kind of hybrid catalyst consisting of methanol and HZSM-5 zeolite in a fixed-bed reactor in a 100 ton/year pilot plant. The biomass synthesis gas was produced by oxygen-rich gasification of corn core in a two-stage fixed bed. The results showed that CO conversions reached 82.00% and 73.55%, the selectivities for DME were 73.95% and 69.73%, and the space–time yields were 124.28 kg m− 3 h− 1 and 203.80 kg m− 3 h− 1 when gas hourly space velocities were 650 h− 1 and 1200 h− 1, respectively. Deoxidation and tar removal from biomass synthesis gas was critical to the stable operation of the DME synthesis system. Using single-pass synthesis, the H2/CO ratio improved from 0.98–1.17 to 2.12–2.22. The yield of DME would be increased greatly if the exhaust was reused after removal of the CO2.  相似文献   
109.
广西南宁郊区杧果园小气候初步研究   总被引:3,自引:0,他引:3  
在冬半年(9~2月),对广西南宁市郊杧果园内及空旷地主要气象要素进行对比观测,结果表明,①果园内日平均光照强度为7390 lx,比空旷地(13830 lx)减少46.6%。②果园内日平均气温为21.3℃,比空旷地(21.5℃)低0.2℃;气温日较差比空旷地低0.1℃。③果园内土壤浅层(0~20cm)日均温为20.4~21.1℃,比空旷地(23.3~24.4℃)低1.8~2.8℃;果园内土温日较差为0.5~6.8℃,比空旷地(1.3~12.8℃)低0.8~6.0℃。④果园内日均相对湿度为77%,比空旷地(74%)高3%。⑤果园内日均风速为0.26m/s,比空旷地(1.25m/s)低79.2%。观测数据表明,杧果园内光照强度减弱、温度日较差降低、相对湿度升高、风速减少的效果极为显著。  相似文献   
110.
流溪河水库丰水年与枯水年营养盐动态的比较分析   总被引:1,自引:0,他引:1  
流溪河水库是一座位于北回归线上的大型山谷型水库,典型的热带-亚热带过渡区水体。为了解该水库的营养盐动态特征,于2008-2009年对水库的营养盐状况和环境因子进行了逐月监测,分析了其丰水年(2008)和枯水年(2009)营养盐动态的动态特征和影响因素。两年的降雨量分别为2660mm和1583mm,降雨主要集中在季风期(4-9月)。丰水期初期(4-5月)是全年营养盐浓度最高的时期,该时期丰水年与枯水年的营养盐空间分布相似:营养盐浓度沿入库河流至水库大坝方向递减,地表径流带来的外源输入是这个期间营养盐变化的主要因素。河流区的营养盐主要受地表径流带来的外源输入的影响,湖泊区营养盐主要受水位变化导致的内源输入的影响。较大的降雨量差异导致两年不同的营养盐季节动态,丰水年有着更高的营养盐水平,更小的DIN/TN与DIP/TP值。河流区较高的营养盐水平会带来湖泊区较高的TN浓度,但不会导致湖泊区更高的TP浓度。  相似文献   
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