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141.
Mohammad Rafiqul Islam Mohd Mostofa Kamal Mohammad Faruk Hossain Jamil Hossain Mohammad Golam Azam Mst Masuma Akhter M. Kamrul Hasan Ibrahim Al-Ashkar Khalid F. Almutairi Ayman EL Sabagh Md Atikur Rahman Muhammad Aamir Iqbal Mohammad Sohidul Islam 《Phyton》2023,92(3):955-981
Drought is one of the critical conditions for the growth and productivity of many crops including mung bean
(Vigna radiata L. Wilczek). Screening of genotypes for variations is one of the suitable strategies for evaluating
crop adaptability and global food security. In this context, the study investigated the physiological and biochemical responses of four drought tolerant (BARI Mung-8, BMX-08010-2, BMX-010015, BMX-08009-7), and four
drought sensitive (BARI Mung-1, BARI Mung-3, BU Mung-4, BMX-05001) mung bean genotypes under wellwatered (WW) and water deficit (WD) conditions. The WW treatment maintained sufficient soil moisture
(22% ± 0.5%, i.e., 30% deficit of available water) by regularly supplying water. Whereas, the WD treatment
was maintained throughout the growing period, and water was applied when the wilting symptom appeared.
The drought tolerant (DT) genotypes BARI Mung-8, BMX-08010-2, BMX-010015, BMX-08009-7 showed a high
level of proline accumulation (2.52–5.99 mg g−1 FW), photosynthetic pigment (total chlorophyll 2.96–3.27 mg g−1
FW at flowering stage, and 1.62–2.38 mg g−1 FW at pod developing stage), plant water relation attributes including relative water content (RWC) (82%–84%), water retention capacity (WRC) (12–14) as well as lower water
saturation deficit (WSD) (19%–23%), and water uptake capacity (WUC) (2.58–2.89) under WD condition, which
provided consequently higher relative seed yield. These indicate that the tolerant genotypes gained better physiobiochemical attributes and adaptability in response to drought conditions. Furthermore, the genotype BMX-
08010-2 showed superiority in terms of those physio-biochemical traits, susceptibility index (SSI) and stress tolerance index (STI) to other genotypes. Based on the physiological and biochemical responses, the BMX-08010-2 was
found to be a suitable genotype for sustaining yield under drought stress, and subsequently, it could be recommended
for crop improvement through hybridization programs. In addition, the identified traits can be used as markers to
identify tolerant genotypes for drought-prone areas. 相似文献
142.
143.
Iron requirement and siderophore production in Rhizobium ciceri during growth on an iron-deficient medium 总被引:1,自引:0,他引:1
Berraho EL. Lesueur D. Diem H.G. Sasson A. 《World journal of microbiology & biotechnology》1997,13(5):501-510
Under conditions of iron limitation many rhizospheric bacteria produce siderophores, ferric iron-specific ligands, which may enhance plant growth by increasing the availability of iron near the roots. Thirty-five strains of Rhizobium ciceri, specific to chickpea (Cicer arietinum L.), were screened for their ability to grow on iron-deficient medium and to produce siderophores. Maximal growth of all strains previously depleted in iron was obtained in medium containing 5 to 10 m of ferric iron. When iron limitation was achieved by the addition of 2,2-bipyridyl or EDDHA [ethylene diamine di(o-hydroxyphenyl) acetic acid] to the medium, only two strains were able to scavenge iron and grow. Siderophore production by these two strains was detected by the Chrome Azurol S assay (CAS), a universal test for siderophores. No hydroxamate-type siderophores were detected in the supernatants of Rhizobium ciceri cultures. However, some strains secreted salicylic acid and 2,3-dihydroxybenzoic acid as phenolate-type siderophores. Addition of ferric iron to the culture medium increased growth yield significantly but depressed the production of siderophores. Although these compounds are produced in response to iron deficiency, nutritive components of the culture medium significantly affected their production. It seems that CuII, MoVI and MnII ions bound competitively with iron to siderophores, resulting in a 34 to 100% increase in production. 相似文献
144.
Choline acetyltransferase activity of spinal cord cell cultures increased by co-culture with muscle and by muscle-conditioned medium 总被引:9,自引:3,他引:6 下载免费PDF全文
Activity of the enzyme choline acetyltransferase (CAT), which mediates the synthesis of the neurotransmitter, acetylcholine, was increased up to 20- fold in spinal cord (SC) cells grown in culture with muscle cells for 2 wk. This increase was directly related to the duration of co-culture as well as to the cell density of both the SC and muscle involved and was not affected by the presence of the acetylcholine receptor blocking agent, α-bungarotoxin. Glutamic acid decarboxylase (GAD) activity was often markedly decreased in SC-muscle cultures while the activities of acetylcholinesterase and several other enzymes were little changed. Increased CAT activity was also observed when SC cultures were maintained in medium which had been conditioned by muscle cells or by undifferentiated cells from embryonic muscle. Muscle-conditioned medium (CM) did not affect the activities of SC cell GAD or acetylcholinesterase. Dilution or concentration of the CM directly affected its ability to increase SC CAT activity , as did the duration and timing of exposure of the SC cells to the CM. The medium could be conditioned by muscle cells in the presence or absence of serum, and remained effective after dialysis or heating to 58 degrees C. Membrane filtration data were consistent with the conclusion that the active material(s) in CM had a molecular weight in excess of 50,000 daltons. We conclude that large molecular weight material that is released by muscle cells is capable of producing a specific increase in CAT activity of SC cells. 相似文献
145.
146.
The regional malaria epidemics of the early 1900s provided the basis for much of our current understanding of malaria epidemiology. Colonel Gill, an eminent malariologist of that time, suggested that the explosive nature of the regional epidemics was due to a sudden increased infectiousness of the adult population. His pertinent observations underlying this suggestion have, however, gone unheeded. Here, the literature on Plasmodium seasonal behaviour is reviewed and three historical data sets, concerning seasonal transmission of Plasmodium falciparum, are examined. It is proposed that the dramatic seasonal increase in the density of uninfected mosquito bites results in an increased infectiousness of the human reservoir of infection and, therefore, plays a key role in "kick-starting" malaria parasite transmission. 相似文献
147.
Espagne E Lespinet O Malagnac F Da Silva C Jaillon O Porcel BM Couloux A Aury JM Ségurens B Poulain J Anthouard V Grossetete S Khalili H Coppin E Déquard-Chablat M Picard M Contamine V Arnaise S Bourdais A Berteaux-Lecellier V Gautheret D de Vries RP Battaglia E Coutinho PM Danchin EG Henrissat B Khoury RE Sainsard-Chanet A Boivin A Pinan-Lucarré B Sellem CH Debuchy R Wincker P Weissenbach J Silar P 《Genome biology》2008,9(5):R77-22
148.
149.
H. EL Arroussi R. Benhima A. Elbaouchi B. Sijilmassi N. EL Mernissi A. Aafsar I. Meftah-Kadmiri N. Bendaou A. Smouni 《Journal of applied phycology》2018,30(5):2929-2941
Microalgal exopolysaccharides represent a potential sustainable alternative for the enhancement and protection of agricultural crops including management of both biotic and abiotic stress. In the present study, we investigated the potential of Dunaliella salina exopolysaccharides (PS) to attenuate the effect of salt stress on growth of Solanum lycopersicum, which was grown under different salinity levels (3 and 6 g L?1 NaCl). The effects of PS treatment on plant growth, osmoprotectant molecules, protein content, and antioxidant enzymes activities of tomato plants under salt stress were analyzed. A metabolomics study showed that the exopolysaccharides released by D. salina contained sulfated moiety along with carbohydrates and uronic acids. The application of sulfated exopolysaccharides on tomato plants alleviated the salt stress and mitigated the decrease in length and dry weight of the plant’s shoot and root systems, as well as that of potassium (K+), and K+/Na+ ratio. Furthermore, the increase in proline, phenolic compounds, Na+, and antioxidant enzymes (CAT, POD, SOD) activities caused by salt stress were attenuated after the exopolysaccharide treatment. GC-MS metabolomics analysis showed that PS treatment allowed the activation and/or inhibition of various metabolic pathways involved in the plant’s tolerance to stress such as jasmonic acid-dependent pathways. This study shows the potential of microalgal exopolysaccharides for enhancing tomato tolerance to salt stress and highlights the possibility of their use as plant growth biostimulants under harsh environmental conditions. 相似文献
150.
Plant Size-dependent Escaping Behavior of Gregarious Nymphs of the Desert Locust, Schistocerca gregaria 总被引:1,自引:0,他引:1
Koutaro Ould Maeno Cyril Piou Sidi Ould Ely Mohamed Abdallahi Ould Babah Benjamin Pélissié Sid’Ahmed Ould Mohamed Mohamed EL Hacen Jaavar Mohamed Etheimine Satoshi Nakamura 《Journal of Insect Behavior》2013,26(5):623-633
The present study involves the tracking of marching bands of more than 300,000 gregarious nymphs of the desert locust, Schistocerca gregaria, to examine shelter plant preference and how species and size of shelter plants and nymphal group sizes jointly influence the escaping behavior of 4th- and 5th-instar gregarious nymphs. Field observations are conducted during daytime and night-time in the Sahara Desert in Mauritania. Three dominant plant species have been identified at the survey site: Hyoscyamus muticus, Panicum turgidum, and Nucularia perrini. The smallest mean plant size among the three plant species is H. muticus. Gregarious nymphs perch on all the three plant species irrespective of time, and form various sizes of groups ranging from <10 to >10,000 nymphs. Groups of gregarious locusts perching on the plants show either escaping or sheltering behavior in response to an approaching observer. Percentages of nymphal groups showing escaping behavior for H. muticus, P. turgidum and N. perrini are 96.4, 47.6 and 19.5 %, respectively. Defensive behavior is not affected by nymphal group size but by species and size of shelter plants. Nymphal groups tend to show escaping behavior when their perching plants are relatively small. No groups escape from their perching plants during night. These results might indicate that gregarious nymphs do not have a strong shelter plant preference and change their defensive behavior depending on species and size of sheltering plants and light conditions. 相似文献