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41.
目的:分析新疆地区近20年来胃癌流行病学特征,探讨其变化规律及发展趋势。方法:回顾性分析和比较1991年、2001年、2011年经新疆维吾自治区人民医院胃镜及病理学诊断确诊为胃癌的病例的一般资料、病理学及内镜下特点,包括性别、年龄、病理类型、发病部位。结果:1991年组:胃癌检出率为2.48%,中位年龄为54岁,男女之比为3-3:1.0,发病部位以胃窦部癌为主,占39.1%;2001年组:检出率为2.39%,中位年龄为61岁,男女之比为3.0:1.0,发病部位以胃体部癌为主,占42.1%;2011年组:检出率为1.48%,中位年龄为63岁,男女之比为3.9:1.0,发病部位以贵门胃底部为主,占34.8%。三组病理学类型均以腺癌为主,检出率有逐年升高趋势,但差异无统计学意义(P〉0.05)。结论:(1)近20年来胃癌发病部位有上移现象,且胃癌检发病率有下降趋势;(2)男性胃癌患者发病率明显高于女性,且近20年来胃癌患者男女比例无明显改变;(3)近20年来胃癌发病中位年龄逐渐增高,且随着年龄的增长发病率逐渐升高,以中老年发病率最高;(4)癌患者病理类型仍以腺癌为主,且近20年来腺癌所占比例无明显变化.  相似文献   
42.
目的:分析新疆地区近20年来胃癌流行病学特征,探讨其变化规律及发展趋势。方法:回顾性分析和比较1991年、2001年、2011年经新疆维吾自治区人民医院胃镜及病理学诊断确诊为胃癌的病例的一般资料、病理学及内镜下特点,包括性别、年龄、病理类型、发病部位。结果:1991年组:胃癌检出率为2.48%,中位年龄为54岁,男女之比为3.3:1.0,发病部位以胃窦部癌为主,占39.1%;2001年组:检出率为2.39%,中位年龄为61岁,男女之比为3.0:1.0,发病部位以胃体部癌为主,占42.1%;2011年组:检出率为1.48%,中位年龄为63岁,男女之比为3.9:1.0,发病部位以贲门胃底部为主,占34.8%。三组病理学类型均以腺癌为主,检出率有逐年升高趋势,但差异无统计学意义(P0.05)。结论:(1)近20年来胃癌发病部位有上移现象,且胃癌检发病率有下降趋势;(2)男性胃癌患者发病率明显高于女性,且近20年来胃癌患者男女比例无明显改变;(3)近20年来胃癌发病中位年龄逐渐增高,且随着年龄的增长发病率逐渐升高,以中老年发病率最高;(4)癌患者病理类型仍以腺癌为主,且近20年来腺癌所占比例无明显变化。  相似文献   
43.
云南蒙自坝区湖泊越冬水鸟组成和变化趋势初报   总被引:2,自引:0,他引:2       下载免费PDF全文
闻丞  李飏 《动物学杂志》2014,49(6):820-829
第264号国际重点鸟区位于云南蒙自坝区,但缺乏系统的鸟类数据。2006-2014 年,每年1月下旬至2月上旬,在蒙自坝区的三个湖泊长桥海、大屯海和三角海(简称“三湖”)进行水鸟调查,累计记录到水鸟12科33属63种。其中有国家I级保护动物1种(黑鹳Ciconia nigra),国家II级保护动物2种(白琵鹭Platalea leucorodia,彩鹮Plegadis falcinellus),极危(CR)鸟类1种(青头潜鸭Aythya baeri),近危(NT)鸟类4种。在长桥海记录的水鸟种类和数量最多,但Shannon-Wiener多样性指数较低,优势度指数较高。在三角海记录到的鸟类种类较多,Shannon-Wiener多样性指数较高而优势度指数较低。在大屯海记录到的鸟种和数量都很少。分别对三湖越冬水鸟种数、数量和雁形目、骨顶鸡和鹳形目水鸟数量变化趋势进行了Man-Kendall检验,发现调查期间,三湖越冬水鸟种数和数量无显著变化,骨顶鸡数量无显著变化趋势,雁形目水鸟略有下降趋势,而鹳形目水鸟有显著下降趋势。鉴于三角海记录到的国家一、二级保护动物和鹳形目水鸟数量,建议扩大第264号国际重点鸟区范围,将其纳入。  相似文献   
44.
Physical pain is a major public health concern. Yet evidence on trends in physical pain around the world barely exists. Using nationally representative data from 146 countries (N = 1.6 million respondents), this paper finds that, all over the world, the percentage of people in pain increased from 26.3 in 2009 to 32.1 in 2021. This rising trend was present in both higher- and lower-income countries. This article also documents pain disparities: In the worldwide population, pain grew faster among women, the less educated, and the poor. Although the aggregate level of pain was greater among the elderly (> 60 years old), the growth in pain was faster among the younger (< 35 years old). These findings hold after controlling for sociodemographic factors. Disparities of pain growth in higher- and lower-income nations and potential explanatory factors are also discussed. Understanding how the level of pain varies over time and across demographic groups is crucial to evaluate and shape public health policies.  相似文献   
45.
BackgroundIn Australia, skin cancer awareness campaigns have focused on raising the awareness and consequences of skin cancer and highlighting the importance of utilising sun protection.MethodsTrends in melanoma incidence and mortality have been explored elsewhere in Australia and this study sought to examine the trends in NSW. Anonymised incidence and mortality data for in situ and invasive melanoma from 1988 to 2014 were obtained from the NSW Cancer Registry. Trends of melanoma incidence and mortality were analysed using segmented regression to allow for changes over time. Birth cohort patterns were assessed using age–period–cohort models.ResultsOver the period, incidence of in situ melanoma increased in all age groups although the rates were lowest in those under 40 years of age. Incidence of invasive melanoma was either stable or decreased in people under 60, while it increased in those aged 60 and above, particularly in men. Age–period–cohort analysis revealed decreasing age-specific incidence of invasive melanoma under 40 years of age. Melanoma mortality over the period was stable or decreased in all groups except in men aged 60 or over. Overall, mortality rates generally declined or remained stable particularly in recent years.ConclusionIt is encouraging that rates of invasive melanoma are declining in the younger age cohorts – which could be attributed to both primary prevention efforts with individuals protecting their skin as well as early detection through self assessment and clinician performed skin checks. In addition, whilst it is important to monitor the increasing rates of in situ melanoma, the increase is likely due to early detection and treatment of melanoma that could have progressed to invasive melanoma and therefore detection whilst still in situ is an improved outcome. Overall, the results demonstrate the need to continue to improve the understanding of and compliance with primary skin cancer prevention measures in order to reduce population UVR exposure and overall melanoma incidence.  相似文献   
46.
王超  刘杨  李新辉  赖子尼 《生态学报》2016,36(16):5276-5283
基于1975—2014年Web of Science数据库中有关直链藻的学术论文,进行了文献计量学分析。研究发现,每年发表论文数呈明显上升趋势,但增幅不大;单篇论文的作者数增长缓慢,近5年每篇论文的作者数开始大于4名;发表论文的学术杂志的影响因子中等偏下,学术影响力不大;以上也映射出此研究方向的冷门性。欧美发达国家对直链藻学术论文的贡献最大,在国际合作方面也处于领先地位。有关直链藻的研究内容仍偏重于基础性研究,分类、多样性和种群生态学方面的研究仍保持一定的热度。淡水湖泊和江河流域是开展直链藻研究的主要区域。  相似文献   
47.
We characterised temporal trends and variability in key indicators of climate and atmospheric deposition chemistry at the twelve terrestrial UK Environmental Change Network (ECN) sites over the first two decades of ECN monitoring (1993–2012) using various statistical approaches. Mean air temperatures for the monitoring period were approximately 0.7 °C higher than those modelled for 1961–1990, but there was little evidence for significant change in air temperature over either the full monthly records or within individual seasons. Some upland ECN sites, however, warmed significantly over the first decade before cooling in the second. Summers at most sites became progressively wetter, and extremes in daily rainfall increased in magnitude. Average wind speeds in winter and spring declined at the majority of sites. Directional trends in summer precipitation could be linked to an atypically prolonged negative deviation in the summer North Atlantic Oscillation (NAO) Index. Several aspects of air quality improved markedly. Concentrations and fluxes of sulphate in precipitation declined significantly and substantially across the network, particularly during the earlier years and at the most polluted sites in the south and east. Precipitation concentrations of nitrate and ammonium, and atmospheric concentrations of nitrogen dioxide also decreased at most sites. There was less evidence for reductions in the loads of wet deposited nitrogen species, while trends in atmospheric ammonia concentration varied in direction and strength between sites. Reductions in acid deposition are likely to account for widespread gradual increases in the pH of soil water at ECN sites, representing partial recovery from acidification. Overall, therefore, ECN sites have experienced marked changes in atmospheric chemistry and weather regimes over the last two decades that might be expected to have exerted detectable effects on ecosystem structure and function. While the downward trend in acid deposition is unlikely to be reversed, it is too early to conclude whether the trend towards wetter summers simply represents a phase in a multi-decadal cycle, or is indicative of a more directional shift in climate. Conversely, the first two decades of ECN now provide a relatively stable long-term baseline with respect to air temperature, against which effects of anticipated future warming on these ecosystems should be able to be assessed robustly.  相似文献   
48.
生物技术发展趋势与预测   总被引:2,自引:1,他引:1  
预测了未来10~20年内生物技术在人类医学领域、农业生物技术领域、工业生物技术领域、生物计算学领域、材料学领域、生物工程领域和环境生物工程领域的主要发展趋势,对生物技术的发展进程也作了预测,并对生物技术在人类疾病治疗方面、农业领域、工业领域、数学领域、材料学科、生物工程方面和环境生物工程领域作出了实际预测。  相似文献   
49.
The US Fish and Wildlife Service's National Wetlands Inventory Project   总被引:1,自引:0,他引:1  
B. O. Wilen  M. K. Bates 《Plant Ecology》1995,118(1-2):153-169
In 1974, the US Fish and Wildlife Service directed its Office of Biological Services to design and conduct an inventory of the Nation's wetlands. The mandate was to develop and disseminate a technically sound, comprehensive data base concerning the characteristics and extent of the Nation's wetlands. The purpose of this data base is to foster wise use of the Nation's wetlands and to expedite decisions that may affect this important resource. To accomplish this, state-of-the-art principles and methodologies pertaining to all aspects of wetland inventory were assimilated and developed by the newly formed project. By 1979, when the National Wetlands Inventory (NWI) Project became operational, it was clear that two very different kinds of information were needed. First, detailed wetland maps were needed for site-specific decisions. Second, national statistics developed through statistical sampling on the current status and trends of wetlands were needed in order to provide information to support the development or alteration of Federal programs and policies. The NWI has produced wetland maps (scale=1:24 000) for 74% of the conterminous United States. It has also produced wetland maps (scale=1:63 360) for 24% of Alaska. Nearly 9000 of these wetland maps, representing 16.7% of the continental United States, have been computerized (digitized). In addition to maps, the NWI has produced other valuable wetland products. These include a statistically-based report on the status and trends of wetlands that details gains and losses in United States wetlands that have occurred from the mid-1970's to the mid-1980's. Other wetland products include a list of wetland (hydric) soils, a national list of wetland plant species, wetland reports for certain individual States such as New Jersey and Florida, and a wetland values data base.  相似文献   
50.
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