首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   146篇
  免费   6篇
  152篇
  2022年   5篇
  2021年   5篇
  2020年   5篇
  2019年   4篇
  2018年   3篇
  2017年   1篇
  2016年   5篇
  2015年   1篇
  2014年   7篇
  2013年   7篇
  2012年   9篇
  2011年   13篇
  2010年   6篇
  2009年   8篇
  2008年   16篇
  2007年   9篇
  2006年   7篇
  2005年   5篇
  2004年   4篇
  2003年   2篇
  2002年   4篇
  2001年   1篇
  1999年   1篇
  1998年   1篇
  1995年   2篇
  1994年   1篇
  1992年   1篇
  1989年   2篇
  1986年   1篇
  1985年   1篇
  1983年   2篇
  1981年   1篇
  1979年   2篇
  1974年   2篇
  1973年   1篇
  1972年   1篇
  1971年   1篇
  1970年   2篇
  1968年   1篇
  1966年   2篇
排序方式: 共有152条查询结果,搜索用时 0 毫秒
141.
A pigment-protein highly dominant in Spirulina is known as C-Phycocyanin. Earlier, in vitro studies has shown that C-phycocyanin is having many biological activities like antioxidant and anti-inflammatory activities, antiplatelet, hepatoprotective, and cholesterol-lowering properties. Interestingly, there are scanty in vivo experimental findings on the immunomodulatory and antioxidant effects of C-phycocyanin. This work is aimed at in vivo evaluation of the effects of C-phycocyanin on immunomodulation and antioxidant potential in Balb/c mice. Our results of in vivo toxicity, immunomodulatory and antioxidant effects of C-Phycocyanin suggests that C-phycocyanin is very safe for consumption and having substantial antioxidant potential and also possess immunomodulatory activities in Balb/c mice in a dosage dependent manner. C-phycocyanin doesn’t cause acute and subacute toxicity in the animal model (male, Balb/c mice) studied. We have reported that C-phycocyanin exhibited in vivo immunomodulation performance in this animal model.  相似文献   
142.
143.
Amino acid utilization and synthetic capacity of two strains (JR & IR) ofMacrophomina phaseoli, a jute parasite, were compared in relation to their virulence. The effects of an extraneous supply of appropriate amino acid on the pathogenicity of the avirulent strain (IR) were also studied. Chromatographic and growth studies revealed that the avirulent strain contained a greater number of amino acids but its utilizing capacity was much lower than that of the virulent strain (JR). Out of 16 amino acids and an amide tested, phenylalanine was found to be most suitable for the growth of the IR strain, the optimum concentration being 0.5 per cent. This concentration did not, however, affect the resistance of the host after foliar application but temporarily increased the pathogenicity when it was given to the pathogen (IR) in vitro. Phenylalanine was detected neither in mycelia of the tested strains nor in the healthy roots of host plants under test conditions. Efficiency of amino acid utilization could be regarded as one of the important biochemical characteristics of the virulent species.  相似文献   
144.
Fungitoxic substance was isolated from the culture filtrate of B. megaterium (B-23). Age of culture and pH of medium influence the fungitoxicity of its culture filtrate. Partially purified toxin was thermolabile, non-dialysable, ethyl acetate soluble, vanillin-sulphuric acid positive and effective within a range of pH 5-9. It exhibited maximum UV absorption at 224 nm. Its melting point was 242 degrees C. The efficacy of this compound was tested on 4 jute parasites namely, C. corchori, C. gloeosporioides, M. roridum and A. citri, of which M. roridum and C. corchori were least and most sensitive to the toxin respectively.  相似文献   
145.
A complete protocol is presented for the first time for the micropropagation of Pongamia pinnata, a biofuel tree, using cotyledonary nodes derived from axenic seedlings. Multiple shoots were induced in vitro from nodal segments through forced axillary branching. Murashige and Skoog (MS) medium supplemented with 7.5 μM benzylaminopurine (BAP) induced up to 6.8 shoots per node with an average shoot length of 0.67 cm in 12 d. Incorporation of 2.5 μM gibberellic acid (GA3) in the medium during the first subculture after establishment and initiation of shoot buds significantly improved the shoot elongation. Single use of GA3 during the first subculture eliminated the need for prolonged culturing on BAP medium. Further use of GA3 in the medium was not useful. Shoot culture was established for at least two subcultures without loss of vigor by repeatedly subculturing the original cotyledonary node on shoot multiplication medium followed by shoot elongation medium after each harvest of the newly formed shoots. Thus, from a single cotyledonary node, about 16–18 shoots were obtained in 60 d. Shoots formed in vitro were rooted on full-strength MS medium supplemented with 1.0 μM indole butyric acid (IBA). Plantlets were successfully acclimated, established in soil, and transferred to the nursery.  相似文献   
146.
Air dried seeds of seven jute (Corchorus capsularis L.) cultivars were irradiated with different doses of X-rays. JRC 1108 and JRC 412 were most and least sensitive to X-rays, respectively. JRC 412 was susceptible to Colletotrichum corchorum both before and after X-irradiation while JRC1108 became more resistant after treatment. Leaf diffusates but not leaf exudates of both non-irradiated and X-irradiated (40,000 r) cvs. exhibited antifungal activity which was more pronounced in case of irradiated JRC 1108. JRC 412 contained greater amounts of amino acids than JRC 1108 both before and after X-irradiation. Signifinon-irradiated, infected ones. The physiological implications of the results are discussed in relation to greater resistance of X-irradiated JRC 1108.  相似文献   
147.
Studies were carried out to find out the role of chemoreceptor sensitivity in the causation of maladaptation syndromes on acute exposure to altitude. The experiments were done in two phases. In phase I, the responses in chemoreceptor sensitivity were studied in altitude acclimatized subjects and compared with those who suffered from either High Altitude Pulmonary Oedema (HAPO) or Acute Mountain Sickness (AMS). In Phase II, a similar comparison was done in two groups of subjects, one representing normal sojourners at 3,500 m and the other being subjects who had just recovered from HAPO. The first phase was done at Delhi; and the second at an altitude of 3,500 m. Parameters of assessment were hypoxic sensitivity, carbon dioxide sensitivity, ventilation (VE), respiratory frequency (Rf), forced vital capacity (FVC), forced expiratory volume at the first second (FEV1), heart rate (HR), blood pressure (BP), and oral temperature (Tor). The results showed significantly lower sensitivity to both hypoxia and carbon dioxide in maladapted subjects, as compared to those who were acclimatized in both the categories suggesting thereby that reduced chemoreceptor sensitivity might be an initiating factor in the causation of maladaptation syndromes at altitude.  相似文献   
148.
Heat output from the right hand was estimated on six healthy young men at varying ambient temperatures, in a temperature-controlled room maintained at 5°, 10°, 15°, 20°, 25°, 30° and 35°C at weekly intervals. The skintemperature of the index finger of both the hands, wrist vein of the right hand and oral temperature, were also recorded during the study. Results indicate that the heat output varies significantly with the changes in ambient temperatures, at higher ranges only. This variation is negligible at lower ambient temperatures. Other parameters supported this observation.  相似文献   
149.
Chicken embryos have been proven to be an attractive vertebrate model for biomedical research. They have helped in making significant contributions for advancements in various fields like developmental biology, cancer research and cardiovascular studies. However, a non‐invasive, label‐free method of imaging live chicken embryo at high resolution still needs to be developed and optimized. In this work, we have shown the potential of photoacoustic tomography (PAT) for imaging live chicken embryos cultured in bioengineered eggshells. Laser pulses at wavelengths of 532 and 740 nm were used for attaining cross‐sectional images of chicken embryos at different developmental stages. Cross‐sections along different depths were imaged to gain knowledge of the relative depth of different vessels and organs. Due to high optical absorption of vasculature and embryonic eye, images with good optical contrast could be acquired using this method. We have thus reported a label‐free method of performing cross‐sectional imaging of chicken embryos at high resolution demonstrating the capacity of PAT as a promising tool for avian embryo imaging.  相似文献   
150.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号