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991.
There is mounting evidence that terrestrial arthropods are declining rapidly in many areas of the world. It is unclear whether freshwater invertebrates, which are key providers of ecosystem services, are also declining. We addressed this question by analysing a long-term dataset of macroinvertebrate abundance collected from 2002 to 2019 across 5009 sampling sites in English rivers. Patterns varied markedly across taxonomic groups. Within trophic groups we detected increases in the abundance of carnivores by 19% and herbivores by 14.8%, while we estimated decomposers have declined by 21.7% in abundance since 2002. We also found heterogeneity in trends across rivers belonging to different typologies based on geological dominance and catchment altitude, with organic lowland rivers having generally higher rates of increase in abundance across taxa and trophic groups, with siliceous lowland rivers having the most declines. Our results reveal a complex picture of change in freshwater macroinvertebrate abundance between taxonomic groups, trophic levels and river typologies. Our analysis helps with identifying priority regions for action on potential environmental stressors where we discover macroinvertebrate abundance declines.  相似文献   
992.
Our recent study compared monitoring data collected using surrogate metrics during 2014–2018 inclusive with baseline data from 2007 to evaluate the trajectory of the population status of the threatened heath skink Liopholis multiscutata in Victoria. The heath skink is a secretive burrowing species that is a habitat specialist and exists in north-western Victoria as a few small and highly disjunct populations on large dunes in semi-arid heathland or mallee. We re-assessed the trajectories of the Victorian populations with additional monitoring data collected in 2021 and found continuing decline across all four Victorian heath skink populations. Urgent management intervention is required to arrest this decline, likely due to predation, reduced availability of habitat and life history and demographic traits that make this species susceptible to decline.  相似文献   
993.
A useful concept that can be invoked to resolve complex bioethical issues is that of moral status (or, human dignity). In this article, we apply this concept to dead human bodies in order to support our view that research on such bodies is permissible. Instead of drawing from salient Western theories of human dignity that account for it by appeals to autonomy or rationality, we will base our investigation on emerging conceptions in African theories of moral status as articulated by Thaddeus Metz and Munamato Chemhuru. Our conclusion is that neither of these theories of moral status, one secular, and the other religious, can accommodate the intuition that we have direct duties of respect towards such bodies because, in relation to Metz's conception, they lack the capacity to enter into social relationships while on Chemhuru's conception, dead bodies appear not to have any meaningful purpose within the hierarchy that captures the ontological systems that determine such status. Consequently, we argue that our analysis provides support for the use of unclaimed cadavers in training and research in medical institutions.  相似文献   
994.
Using the Chinese Longitudinal Healthy Longevity Survey (CLHLS) from 2008 to 2018 accompanied by the growth curve model, we examined the association between early socioeconomic status, social mobility, and divergent cognitive trajectories in later life within a society undergoing significant transformation. The study confirmed a positive relationship between socioeconomic status in early life and cognitive ability in later life. However, socioeconomic status in adulthood is associated with better cognitive ability in old age compared to that in childhood. Meanwhile, upward social mobility mitigates the negative correlation between socioeconomic disadvantage in early life and cognitive ability in later life. In addition, the inequality in socioeconomic status at earlier stages resulted in heterogeneous cognitive trajectories, with the double cumulative disadvantage effect resulting from education being particularly noteworthy. Thus, Chinese health policy should focus on the earlier stages of life, actively promoting inclusive family policies and improving the family's role in protecting childhood from an adverse environment. Simultaneously, education and employment fairness should be strengthened to accelerate social mobility and enhance the “Health Repair Mechanism” of the second life course.  相似文献   
995.
Background and objectivesWe aimed to investigate geographical disparity in cancer survival in 9 provincial population-based cancer registries in Iran from 2015 to 2016.Material and methodIn the current study, data from 90,862 adult patients (aged >15 years) diagnosed with cancer were retrieved from 9 population-based cancer registries across Iran. Five-year survival rates were estimated by applying relative survival approaches. We also applied the international cancer survival standard weights for age standardization. Finally, we calculated the excess hazard ratio (EHR) for each province adjusted for age, sex, and cancer sites to estimate the excess hazard ratio of mortality compared to the capital province (Tehran).ResultsThe largest gap in survival was observed in more curable cancer types, including melanoma (41.4%), ovary (32.3%), cervix (35.0%), prostate (26.7%), and rectum (21.4%), while the observed geographical disparity in lethal cancers such as lung, brain, stomach, and pancreas was less than 15%. Compared to Tehran, we found the highest excess hazard of death in Western Azerbaijan (EHR=1.60, 95% CI 1.51, 1.65), Kermanshah (EHR=1.52, 95% CI=1.44, 1.61), and Kerman (EHR=1.46, 95% CI=1.38, 1.53). The hazard ratio of death was almost identical in Isfahan (EHR=1.04, 95% CI=1.03, 1.06) and Tehran provinces.ConclusionProvinces with higher HDI had better survival rates. IRANCANSURV study showed regional disparities in cancer survival in Iran. Cancer patients in provinces with a higher Human Development Index (HDI) had a higher survival rate and lived longer compared to the patients in provinces with medium and low HDI regions.  相似文献   
996.
摘要 目的:探讨微生态制剂联合免疫增强型肠内营养治疗重症肺炎患者的临床疗效及对患者营养状态、肠道菌群、T淋巴细胞亚群水平及炎症反应指标的影响。方法:选取2018年10月~2022年1月邯郸市中心医院收治的126例重症肺炎患者,以随机数字表法分为观察组、对照组各63例。对照组采用免疫增强型肠内营养治疗,观察组在对照组基础上加用微生态制剂治疗。比较两组临床疗效、症状变化情况、治疗前后营养指标[血红蛋白(HGB)、白蛋白(ALB)、前白蛋白(PA)]、肠道菌群(双歧杆菌、乳酸杆菌、肠球菌、大肠埃希菌、弯曲杆菌)、T淋巴细胞亚群(CD3+、CD4+、CD8+、CD4+/CD8+)、炎症因子水平[白介素-6(IL-6)、可溶性血管细胞黏附分子1(sVCAM-1)、C反应蛋白(CRP)]。结果:观察组总有效率(93.65%)高于对照组(80.95%)(P<0.05);观察组体温恢复正常时间、肺部阴影消失时间、咳嗽改善时间、住院时间较对照组短(P<0.05);治疗后观察组HGB、ALB、PA水平较对照组升高(P<0.05);治疗后观察组双歧杆菌较对照组高,乳酸杆菌、肠球菌、大肠埃希菌、弯曲杆菌较对照组降低(P<0.05);治疗后观察组CD8+较对照组降低,CD3+、CD4+、CD4+/CD8+较对照组高高(P<0.05);治疗后观察组血清IL-6、sVCAM-1、CRP水平较对照组降低(P<0.05)。结论:微生态制剂联合免疫增强型肠内营养治疗重症肺炎效果显著,可有效促使症状改善,调节肠道菌群、增强机体免疫功能、改善营养状态、减轻机体炎症反应,值得临床借鉴应用。  相似文献   
997.
摘要 目的:探讨腹式呼吸训练法对慢性阻塞性肺疾病(COPD)伴Ⅱ型呼吸衰竭患者肺通气状态、血气指标及运动耐力的影响。方法:选择我院2020年07月2022年12月期间收治的100例COPD伴Ⅱ型呼吸衰竭患者,根据随机数字表法将患者分为对照组[常规治疗基础上接受双水平气道正压(BIPAP)辅助通气,n=50]和研究组(对照组的基础上接受腹式呼吸训练法干预,n=50)。对比两组临床相关指标、肺通气状态、血气指标及运动耐力指标。结果:研究组的喘憋消失时间、体温恢复正常时间、住院时间、肺部啰音消失时间短于对照组(P<0.05)。两组干预1周后第1秒呼气的最大容积(FEV1)、最大自主分钟通气量(MVV)、用力肺活量(FVC)均升高,且研究组高于对照组(P<0.05)。两组干预1周后氧分压(PaO22)、血氧饱和度(SpO2)均升高,且研究组高于对照组;二氧化碳分压(PaCO2)下降,且研究组低于对照组(P<0.05)。两组干预1周后6 min步行距离(6MWT)升高,且研究组高于对照组(P<0.05)。结论:腹式呼吸训练法有助于改善COPD伴Ⅱ型呼吸衰竭患者的临床症状,调节肺通气状态、血气指标,提高运动耐力。  相似文献   
998.
Stream valleys as wetlands   总被引:2,自引:2,他引:0  
Wetlands as a component of discharge areas have been reduced to mere stream channels in the larger part of The Netherlands. The original shape and condition are described with help of data from the past and from some small remnants. The typical Dutch type of running water is the lowland stream, fed predominantly by rain and groundwater. Its nature is nutrient-poor in the upper course and eutrophying gradually downstream. The chemical composition of streamwater, the vegetation in the floodplain and the flora and fauna in the stream reflect this gradient. Some attention is paid to the amount and cycling of minerals and nutrients. It is shown that the input of nutrients is not a limiting factor for primary production, but under natural conditions light is limiting. Threats to stream wetlands are the composition of the precipitation, fertilization of the discharge area and water management measures such as draining and canalization. As a result perspectives for a qualitative recovery are unfavourable. Restoration of the shape of streams, however, is more prospective and several restoration programs are in execution.  相似文献   
999.
A model of maize stomatal behaviour has been developed, in which stomatal conductance is linked to the concentration of abscisic acid ([ABA]) in the xylem sap, with a sensitivity dependent upon the leaf water potential (Ψ1). It was tested against two alternative hypotheses, namely that stomatal sensitivity to xylem [ABA] would be linked to the leaf-to-air vapour pressure difference (VPD), or to the flux of ABA into the leaf. Stomatal conductance (gs) was studied: (1) in field-grown plants whose xylem [ABA] and Ψ1 depended on soil water status and evaporative demand; (2) in field-grown plants fed with ABA solutions such that xylem [ABA] was artificially raised, thereby decreasing gs and increasing Ψ1 and leaf-to-air VPD; and (3) in ABA-fed detached leaves exposed to varying evaporative demands, but with a constant and high Ψ1. The same relationships between gs, xylem [ABA] and Ψ1, showing lower stomatal sensitivity to [ABA] at high Ψ1, applied whether variations in xylem [ABA] were due to natural increase or to feeding, and whether variations in Ψ1, were due to changes in evaporative demand or to the increased Ψ1 observed in ABA-fed plants. Conversely, neither the leaf-to-air VPD nor the ABA flux into the leaf accounted for the observed changes in stomatal sensitivity to xylem [ABA]. The model, using parameters calculated from previous field data and the detached-leaf data, was tested against the observations of both ABA-fed and droughted plants in the field. It accounted with reasonable accuracy for changes in gs (r2 ranging from 0.77 to 0.81). These results support the view that modelling of stomatal behaviour requires consideration of both chemical and hydraulic aspects of root-to-shoot communication.  相似文献   
1000.
Paternity assessment through DNA fingerprinting by synthetic oligonucleotide probes was applied to one birth cohort in a social group of free-ranging rhesus macaques (Macaca mulatta) on Cayo Santiago. The 11 group males and 9 males from other groups were observed mating with the females. Paternity was determined for 11 of the 15 infants. Male dominance rank was not associated with reproductive success. High-ranking resident males (N=5) sired 27% of the infants born during a one-year study. Four of the 11 infants of known paternity were sired by males of other social groups. The four infants of unknown paternity were sired either by males not observed mating with the females or the low-ranking male who was not fingerprinted. Male dominance rank was not associated with reproductive activity during conception cycles. These results suggest that the effect of rank on male reproductive success is not a predictable correlation, but a conditional probability.  相似文献   
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