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11.
Phytoplankton respiratory electron transport system (P-ETS) activities were studied in two cruises in Taiwan Strait (Aug. 1997 and Feb. -Mar.1998) and two cruises in Xiamen Harbour (Oct., 1997 and Apr.,1998). Results showed that P-ETS activity in the surface water of southern Yaiwan Strait in summer was homogeneous [mean value of 0.106 μ102/(L.h)], inhomogeneous in northern Yaiwan Strait in winter. Variation of P-ETS activity in middle part of the Strait was not obvious between summer and winter. Mean P-ETS activity of Xiamen Harbour in autumn was 0.255 μ102/(L.h) with a little higher value in Jiulong River estuary areas. In spring, P-ETS activity was more homogeneously distributed and the mean value was 1.076 μ102/(L.h). P-ETS activity in spring was obviously higher than in autumn in Xiamen Harbour. Vertical distribution of P-ETS in Taiwan Strait was homogeneous at some stations in winter and in summer. An obvious daily variation of P-ETS activity was recorded at Stn 9837, high at midnight and low in the early morning. Significant correlation between P-ETS activity and Chl-a was observed. Results also showed that the ratio of estimated respiratory rate to photosynthetic rate varied seasonally, high in winter (0.41) and low in summer (0.12).  相似文献   
12.
目的:观察归脾合剂治疗新型冠状病毒感染后心脾两虚型不寐的临床疗效。方法:将新型冠状病毒感染后心脾两虚型不寐患者60例随机分为2组,每组各30例。对照组口服阿普唑仑片,治疗组在对照组基础上联合口服归脾合剂,连续治疗15 d。评价2组患者临床疗效、匹兹堡睡眠质量指数量表(PSQI)评分、中医证候积分及不良反应发生情况。结果:总有效率治疗组为96.67%(29/30),明显高于对照组的80.00%(24/30),2组比较,差异有统计学意义(P<0.05);2组PSQI评分、中医证候积分治疗前后组内比较及治疗后组间比较,差异均有统计学意义(P<0.05);不良反应发生率治疗组为9.99%(3/30),对照组为13.32%(4/30),2组比较,差异无统计学意义(P>0.05)。结论:归脾合剂治疗新型冠状病毒感染后心脾两虚型不寐的疗效优于单用西药治疗,可提高临床疗效,改善患者睡眠质量,且不增加不良反应。  相似文献   
13.
Growth and energy budget of marine amphipod juvenile Eogammarus possjeticus at different temperatures(20°C,24°C, 26°C, 28°C, 30°C, 32°C and 34°C) were investigated in this study. The results showed that the cumulative mortality rate increased significantly with rising temperature(p0.01), and exceeded 50% after 24 h when temperature was above 30°C. With the temperature increasing from 20°C to 26°C, the ingestion rate and absorption rate increased, but decreased significantly above 28°C(p0.01), indicating a decline in feeding ability at high temperatures. The specific growth rate increased with rising temperature, but decreased significantly(p0.01) after reaching the maximum value at 24°C. Similarly, the oxygen consumption and ammonia emission rates also showed a trend of first increase and then decrease. However, the O:N ratio decreased first and then increased with rising temperature, indicating that the energy demand of E. possjeticus juvenile transferred from metabolism of carbohydrate and lipid to protein. In the energy distribution of amphipods, the proportion of each energy is different. With rising temperature, the ratio of the energy deposited for growth accounted for ingested gross energy showing a trend of decrease, while the energy lost to respiration, ammonia excretion, and feces accounted for ingested gross energy being showed a trend of increase. It seemed that rising temperature increased the metabolism and energy consumption of the amphipods and, meanwhile, decreased the energy used for growth, which may be an important reason for the slow growth and small body size of the amphipods during the summer high-temperature period.  相似文献   
14.
目的:研究咳喘宁对哮喘豚鼠白细胞介素(IL-6)和肿瘤坏死因子(TNF-α)的调节作用。方法:将60只豚鼠随机分为空白组10只、造模组50只。利用呼吸道合胞病毒(RSV)感染豚鼠建立动物模型,加鸡卵白蛋白(OVA)诱导建立哮喘模型。造模组成功后再将其随机分为模型组,咳喘宁高、中、低剂量组,西药组,每组各10只。咳喘宁高、中、低剂量组分别给予不同剂量的咳喘宁口服液,西药组给予地塞米松+利巴韦林,空白组、模型组给予0.9%氯化钠注射液。经治疗7 d后,应用HE染色法检测咳喘宁对RSV哮喘豚鼠模型的治疗效果;收集支气管肺泡灌洗液(BALF)并采集心脏血,用酶联免疫吸附(ELISA)法分析血清、BALF中IL-6和TNF-α的含量。结果:血清、BALF中IL-6、TNF-α含量,模型组与空白组比较,差异有统计学意义(P<0.05),说明造模成功。咳喘宁高、中、低剂量组及西药组与模型组比较,差异均有统计学意义(P<0.05)。咳喘宁高剂量组与西药组比较,差异亦有统计学意义(P<0.05)。结论:咳喘宁可以降低炎性因子水平,控制气道炎症,调节IL-6和TNF-α含量,改善哮喘模型豚鼠的肺组织病理变化。  相似文献   
15.
Seven stations were established in the Quanzhou Bay (24.73°-24.96°N, 118.50°-118.70°E) in China on three cruises to determine the concentrations of polycyclic aromatic hydrocarbons (PAHs) and the numbers of PAH-degrading bacteria in surface sediments. Assessing the biodegradation poten- tial of indigenous microorganisms by measuring the respiratory intensity with the addition of PAHs in sediment samples was also one of the aims of this study. The results show that the total PAH concentrations of the sedimen...  相似文献   
16.
目的:观察人参败毒散加减治疗脾肺气虚、寒湿郁肺型新型冠状病毒感染(或肺炎)的临床疗效。方法:选择脾肺气虚、寒湿郁肺型新型冠状病毒感染(或肺炎)患者28 例,采用西药联合人参败毒散加减治疗。观察患者平均连续2次呼吸道标本核酸检测阴性的时间、中医证候积分和复阳情况。结果:平均连续2次核酸转阴时间为(10.22±8.84)d;治疗后患者胸闷气短、咳嗽咳痰、纳差、便溏、神疲乏力症状积分均较治疗前降低,差异均有统计学意义(P<0.05);出院后14 d有1 例患者在隔离点出现复阳。结论:人参败毒散加减治疗脾肺气虚、寒湿郁肺型新型冠状病毒感染(或肺炎)疗效颇佳,且可对反复复阳患者起到稳定转阴的作用,值得临床推广运用。  相似文献   
17.
呼吸系统疾病对儿童的身体健康有极大影响,其发生与气象条件有密切关系。为探讨秦皇岛地区气象条件对儿童下呼吸道疾病的影响,预测就诊人数,为医疗气象服务提供新方法,利用秦皇岛地区2015-2016年儿童下呼吸道疾病就诊人数资料和同期气象资料,分别使用逐步回归分析和BP人工神经网络建立儿童下呼吸道疾病就诊人数预测模型,并对预测效果进行评价。结果表明,气象条件对儿童下呼吸道疾病的发生有显著影响,特别是阶段性天气变化与气候异常对就诊人数影响较大。就诊人数与气温及平均相对湿度呈负相关关系,与气压、风速及前72 h气温变幅呈正相关关系,与气温相关性最好,与气压、平均相对湿度相关性次之。逐步回归法与BP人工神经网络模型的预测准确率分别为72.75%、76.30%。2种预测模型中,BP人工神经网络模型的整体表现更为出色。  相似文献   
18.
Litopenaeus vannamei, a euryhaline species, can be cultured at a wide range of salinities. The emergence of freshwater pond-culture of L. vannamei is an important prelude to the continued development of shrimp culture in China. In this study, we compared the respiratory metabolism of juvenile L. vannamei cultured in freshwater and saltwater by measuring their oxygen consumption rate (OCR), ammonium-type nitrogen excretion rate (AER) and pyruvate kinase (PK) and lactate dehydrogenase (LDH) activities at different molting stages in order to physiecologically characterize juvenile L. vannamei under freshwater conditions. The results showed that OCR was significantly higher in saltwater than in freshwater at all stages of molting cycle. However, variation of OCR among molting stages in saltwater was similar with that in freshwater, and the highest OCR was observed at post-molting stage. At all stages of molting cycle, AER was significantly higher in freshwater than in saltwater, and the highest was observed at post-molting stage. The activity of PK was significantly higher in saltwater than in freshwater. Conversely, the activity of LDH was higher in freshwater than in saltwater in general. Significant variation of PK and LDH activities in molting cycle was observed in saltwater and freshwater. The results indicated that aerobic metabolism of juvenile L. vannamei was more active in saltwater than in freshwater; while its protein metabolism was more active in freshwater than in saltwater.  相似文献   
19.
作为典型的降河洄游鱼类,花鳗鲡(Anguilla marmorata)在我国主要分布于长江下游及以南水域。中草药作为抗生素等化学类渔药的绿色替代品,对养殖鱼类具有抗菌、消炎、促生长等多种功效。为研究中草药复方在花鳗鲡病害防治中的作用,扩大水产养殖业渔药研制与应用的选择,采用非连续性密度梯度离心法对花鳗鲡外周血白细胞的分离体系进行了优化,试验设置了密度分别为1.031、1.043、1.056、1.067、1.090 g/mL的五种分离液,分别采用染色观察法和流式细胞术检测各分离液中白细胞浓度;以浓度1.0mg/mL的五种复方药液分别与105cell/mL的白细胞悬液共孵育2h后,分别采用NBT法和流式细胞术测定白细胞的呼吸暴发活性和吞噬能力,评价五种中草药复方(多糖复方Dt,白头翁复方Btw,板蓝根复方Blg,大黄复方Dh,百里酚复方Blf)对花鳗鲡外周血白细胞的激活作用。结果显示:1.043g/mL和1.056g/mL的分离液所分离获得白细胞浓度均接近105cell/mL,可在后续实验中叠加使用该两个浓度的分离液分离获得白细胞;流式细胞术检测白细胞浓度比染色观察法更为灵敏准确;5种复方均能显著提高花鳗鲡外周血白细胞的呼吸暴发活性(P<0.05),大小依次为Blg>Dt>Btw>Blf>Dh;Dt和Blg能显著提高白细胞吞噬率(P<0.05),Btw、Blf、Dh也能提高白细胞吞噬率,但差异不显著(P>0.05);5种复方对发生吞噬白细胞比率的影响差异不显著(P>0.05)。  相似文献   
20.
Although much environmental justice research tacitly assumes that unequal environmental exposures produce geographic disparities in adverse health outcomes, very few empirical environmental justice studies have tested that assumption. This article does so by using estimates of exposure to air toxics disaggregated by emission source (point and mobile) to predict children's hospitalization rates for both asthma and respiratory infections in El Paso, Texas. Air toxics emissions from most source categories were found to be significant predictors of children's respiratory infection hospitalization rates, but not asthma hospitalization rates, at the census tract level. Findings suggest that sociospatial disparities in respiratory infection rates might be linked to environmental inequalities.  相似文献   
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