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91.
92.
In the present study, trikatu, an herbal compound was evaluated for its immunomodulatory and anti-inflammatory properties with reference to cell mediated immune responses (delayed type hypersensitivity reaction), humoral immune response (haemagglutination titer and plaque forming assay), macrophage phagocytic index, circulating immune complex and inflammatory mediators in rats. For comparison purposes, indomethacin was used as a reference drug for anti-inflammatory studies. The results obtained in our study showed a significant decrease in cell mediated immune responses, humoral immune responses (haemagglutination titre and plaque forming assay) and macrophage phagocytic index in trikatu treated rats (1000 mg/kg/b.wt.) compared to control animals implying its immunosuppressive property. In addition, significant anti-inflammatory effects were observed in trikatu treated adjuvant induced arthritic rats by a reduction in the levels of circulating immune complexes and inflammatory mediators (TNF-alpha and Interleukin-1beta). Thus, in conclusion, our data suggest that trikatu could be considered as a potential anti-inflammatory agent for treating autoimmune inflammatory disorders like rheumatoid arthritis with immunosuppressive property.  相似文献   
93.
The effects of supplementing diets with acetone extract (1% w/w) from four medicinal plants (Bermuda grass Cynodon dactylon, H1, beal Aegle marmelos, H2, winter cherry Withania somnifera, H3 and ginger Zingiber officinale, H4) on growth, the non‐specific immune response and ability to resist pathogen infection in tilapia Oreochromis mossambicus were assessed. In addition, the antimicrobial properties of the extract were assessed against Vibrio alginolyticus, Vibrioparahaemolyticus, Vibrio mimicus, Vibrio campbelli, Vibrio vulnificus, Vibrio harveyi and Photobacterium damselae. Oreochromis mossambicus were fed 5% of their body mass per day for 45 days, and those fed the experimental diets showed a greater increase in mass (111–139%) over the 45 days compared to those that received the control diet (98%). The specific growth rate of O. mossambicus fed the four diets was also significantly greater (1·66–1·93%) than control (1·52%) diet‐fed fish. The blood plasma chemistry analysis revealed that protein, albumin, globulin, cholesterol, glucose and triglyceride levels of experimental fish were significantly higher than that of control fish. Packed cell volume of the blood samples of experimental diet‐fed fish was also significantly higher (34·16–37·95%) than control fish (33·0%). Leucocrit value, phagocytic index and lysozyme activity were enhanced in fish fed the plant extract‐supplemented diets. The acetone extract of the plants inhibited growth of Vibrio spp. and P. damselae with extracts from W. somnifera showing maximum growth inhibition. A challenge test with V. vulnificus showed 100% mortality in O. mossambicus fed the control diet by day 15, whereas the fish fed the experimental diets registered only 63–80% mortality at the end of challenge experiment (30 days). The cumulative mortality index for the control group was 12 000, which was equated to 1·0% mortality, and accordingly, the lowest mortality of 0·35% was registered in H4‐diet‐fed group.  相似文献   
94.
山东蒙山植物多样性及其海拔梯度格局   总被引:10,自引:1,他引:10  
高远  慈海鑫  邱振鲁  陈玉峰 《生态学报》2009,29(12):6377-6384
2007年7月和2008年7月,采用典型取样法,沿海拔梯度对蒙山自然植被进行调查,发现区域地带性植被为麻栎(Quercus acutissima)林,主要植被类型为麻栎群落、赤松(Pinus densiflora)群落、油松(Pinus tabuliformis)群落、日本落叶松(Larix kaempferi)群落、黑松(Pinus thunbergii)群落和刺槐-麻栎(Robinia pseudoacacia-Q.acutissima)群落,麻栎群落略占优势,已具备继续向温带落叶阔叶林演替的条件基础.蒙山各层次植物物种丰富度呈现出草本层>灌木层>乔木层特征,Shannon-Wiener多样性指数和Simpson多样性指数整体规律为灌木层>草本层>乔木层.以蒙山森林群落不同层次的各种物种多样性指数和森林群落总体重要值为测度指标,均判断蒙山植被演替正处于亚顶极群落阶段.蒙山植物多样性沿海拔梯度呈现出近似中海拔高的单峰格局,这除受温度、湿度、人为干扰与面积外,蒙山植被亚顶极群落演替现状与所调查区域仅有800 m的海拔梯度也是重要影响因素.  相似文献   
95.
黄伞菌丝蛋白质营养价值评价   总被引:3,自引:0,他引:3  
本文测定了黄伞Pholiotaadiposa菌丝粗蛋白含量和氨基酸组成,采用国际上通用的营养价值评价方法,对其蛋白质的营养价值进行全面评价,并与营养价值较高的白灵侧耳Pleurotusnebrodensis、刺芹侧耳Pleurotuseryngii和金顶侧耳Pleurotrscitrinopileatus进行比较。分析结果表明,黄伞菌丝的必需氨基酸含量最高,占其氨基酸总量的43.9%,蛋白质的氨基酸评分(AAS)、化学评分(CS)、必需氨基酸指数(EAAI)、生物价(BV)、营养指数(NI)和氨基酸比值系数分(SRCAA)分别为92.0、71.3、88.5、84.8、40.4和78.8,六项指标均比参比食用菌高。结果说明黄伞菌丝具有很高的营养价值。  相似文献   
96.
Pack ice, brines and seawaters were sampled in October 2003 in the East Antarctic sector to investigate the structure of the microbial communities (algae, bacteria and protozoa) in relation to the associated physico-chemical conditions (ice structure, temperature, salinity, inorganic nutrients, chlorophyll a and organic matter). Ice cover ranged between 0.3 and 0.8 m, composed of granular and columnar ice. The brine volume fractions sharply increased above −4°C in the bottom ice, coinciding with an important increase of algal biomass (up to 3.9 mg C l−1), suggesting a control of the algae growth by the space availability at that period of time. Large accumulation of NH4 + and PO4 3− was observed in the bottom ice. The high pool of organic matter, especially of transparent exopolymeric particles, likely led to nutrients retention and limitation of the protozoa grazing pressure, inducing therefore an algal accumulation. In contrast, the heterotrophs dominated in the underlying seawaters.  相似文献   
97.
The gas exchange of 19 widely different warm climate species was observed at different leaf to air vapour pressure deficits (VPD). In all species stomata tended to close as VPD increased resulting in a decrease in net photosynthesis. The absolute reduction in leaf conductance per unit increase in VPD was greatest in those species which had a large leaf conductance at low VPDs. This would be expected even if stomata of all species were equally sensitive. However the percentage reduction in net photosynthesis (used as a measure of the relative sensitivity of stomata of the different species) was also closely related to the maximal conductance at low VPD. Similarily the relative sensitivity of stomata to changes in VPD was closely related to the weighted stomatal density or crowding index.The hypothesis is presented that stomatal closure at different VPDs is related to peristomatal evaporation coupled with a high resistance between the epidermis and the mesophyll and low resistance between the stomatal apparatus and the epidermal cells. This hypothesis is consistent with the greater relative sensitivity of stomata on leaves with a high crowding index.The results and the hypothesis are discussed in the light of selection, for optimal productivity under differing conditions of relative humidity and soil water availablility, by observation of stomatal density and distribution on the two sides of the leaf.Visiting scientist, plant physiologist and research assitant of the Cassava Program  相似文献   
98.
We examined the effects of the conversion of tropical forest to pasture on soil organic matter (SOM) origin and quality along a chronosequence of sites, including a primary forest and six pastures. Bulk soil samples received a physical size-fractionation treatment to assess the contribution of each compartment to total SOM pool. Besides a general increase in total C and N stocks along the chronosequence, we observed a reduction of the relative contribution of the coarser fractions to total soil C content, and an increased concentration in the finer fractions. The origin of the C in each size fraction was established from measurements of13C abundance. After 80 years about 93% of the C in the least humified fraction of the top 10 cm of soil was of pasture origin, while in the most humified it was 82%. Chemical analyses indicated that the fine silt and coarse clay fractions contained the most refractory carbon.  相似文献   
99.
不同肝病变组织中CD34、CD31、Ki-67的表达及意义   总被引:3,自引:0,他引:3  
目的比较正常肝组织、慢性肝炎、肝硬化、肝细胞肝癌组织及肝转移腺癌中CD34、CD31、Ki-67不同表达,寻找有助于鉴别不同性质病变的生物学标记物.方法正常肝及病变肝组织标本共104例;其中,正常肝组织10例;慢生C型肝炎组织73例;肝硬化组织7例;肝细胞肝癌7例;结肠癌肝转移5例;乳腺癌肝转移2例.73例慢性C型肝炎组织全部为肝穿活检标本,其余组织均为手术切除标本.所有病例标本分别行CD34、CD31、Ki-67免疫组织化学染色,半定量评分系统评价染色结果.统计学分析结果数据.结果在非肿瘤组织,抗CD34阳性染色主要存在于汇管区,亦可见于汇管区周围的肝实质内血窦.阳性染色内皮细胞呈点状、线状、半环状及环状,散在或簇状分布.肿瘤组织内抗CD34阳性染色特征与非肿瘤组织相似,阳性染色血管在肿瘤组织内散布分布.CD34指数在各病变组中的表达排列顺序依次为:肝细胞肝癌>乳腺癌肝转移>结肠癌肝转移>肝硬化>慢性C型肝炎>正常肝组织,从正常肝组织至慢性肝炎至肝细胞肝癌,CD34表达明显增强.组织中,抗CD31阳性染色分布、定位、形态特征与CD34相似.CD31在慢性肝炎、肝硬化、肝细胞肝癌、结肠癌肝转移及乳腺癌肝转移组织中阳性表达率分别为:6.8%(5/73)、100%(7/7)、100%(7/7)、100%(5/5)、100%(2/2);肝癌组织中CD31染色强度明显大于非癌组织中,组间比较具有显著差异(P<0.05).Ki-67阳性染色细胞呈棕黄色核着色,散在分布于肝实质内.阳性染色细胞无形态特殊性,亦无分布上的特殊性.Ki-67在各病变组间的阳性表达率分别为:64.4%(47/73)、28.6%(2/7)、100%(7/7)、100%(5/5)、100%(2/2),其中以在结肠癌肝转移组织中表达最明显;组间比较具有非常显著差异(P<0.05).在正常肝脏、慢性C型肝炎、肝硬化、肝细胞肝癌CD34、CD31、Ki-67三种生物学标记物在同一标本同时表达的阳性率分别为:0%(0/0)、4.1%(3/73)、28.6%(2/7)、100%(7/7),CD34、CD31、Ki-67其中任两种同时表达的阳性率分别为0%(0/10)、63.0%(46/73)、100%(7/7)、100%(7/7).结论 CD34是慢性肝病、肝癌临床病理评价的指标之一,CD34与CD31、Ki-67同时分析有助于建立可靠的诊断.  相似文献   
100.
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