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91.
The performance of a clinical trial for pharmaceutical agents is usually undertaken only after there is likely benefit demonstrated from the use of the putative agent. The consideration of botanical products as pharmaceutical agents must similarly go through a rigorous evaluation process. The present work reviews the recently published phase II study evaluating the effectiveness of black cohosh and red clover in a randomized trial with conjugated equine estradiol/medroxyprogesterone acetate and placebo for the treatment of menopausal symptoms. We analyze the possible reasons why this study failed to show benefit for either botanical product in reducing menopause-related vasomotor symptoms. 相似文献
92.
93.
Jang DS Park EJ Hawthorne ME Vigo JS Graham JG Cabieses F Santarsiero BD Mesecar AD Fong HH Mehta RG Pezzuto JM Kinghorn AD 《Journal of agricultural and food chemistry》2002,50(22):6330-6334
A new bicyclic diarylheptanoid, rel-(3S,4aR,10bR)-8-hydroxy-3-(4-hydroxyphenyl)-9-methoxy-4a,5,6,10b-tetrahydro-3H-naphtho[2,1-b]pyran (1), as well as four known compounds, 1,2-dihydro-1,2,3-trihydroxy-9-(4-methoxyphenyl)phenalene (2), hydroxyanigorufone (3), 2-(4-hydroxyphenyl)naphthalic anhydride (4), and 1,7-bis(4-hydroxyphenyl)hepta-4(E),6(E)-dien-3-one (5), were isolated from an ethyl acetate-soluble fraction of the methanol extract of the fruits of Musa x paradisiaca cultivar, using a bioassay based on the induction of quinone reductase (QR) in cultured Hepa1c1c7 mouse hepatoma cells to monitor chromatographic fractionation. The structure and relative stereochemistry of compound 1 were elucidated unambiguously by one- and two-dimensional NMR experiments ((1)H NMR, (13)C NMR, DEPT, COSY, HMQC, HMBC, and NOESY) and single-crystal X-ray diffraction analysis. Isolates 1-5 were evaluated for their potential cancer chemopreventive properties utilizing an in vitro assay to determine quinone reductase induction and a mouse mammary organ culture assay. 相似文献
94.
Burdette JE Chen SN Lu ZZ Xu H White BE Fabricant DS Liu J Fong HH Farnsworth NR Constantinou AI Van Breemen RB Pezzuto JM Bolton JL 《Journal of agricultural and food chemistry》2002,50(24):7022-7028
The roots/rhizomes of Cimicifuga racemosa L. (Nutt.) (black cohosh) have traditionally been used to treat menopausal symptoms through an unknown mechanism of action. In an effort to determine if black cohosh had additional health benefits, methanol extracts were investigated for their potential to scavenge reactive oxygen species and to protect against menadione-induced DNA damage. These extracts effectively scavenged 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radicals. In addition, the extracts showed dose-dependent decreases in DNA single-strand breaks and oxidized bases induced by the quinone menadione using the comet (single-cell gel electrophoresis assay) and fragment length associated repair enzyme assays, respectively. Bioassay-directed fractionation of the methanolic extracts using the DPPH assay as a monitor led to the isolation of nine antioxidant active compounds: caffeic acid (1), methyl caffeate (2), ferulic acid (3), isoferulic acid (4), fukinolic acid (5), cimicifugic acid A (6), cimicifugic acid B (7), cimicifugic acid F (8), cimiracemate A (9), and cimiracemate B (10). Six of these antioxidants were found to reduce menadione-induced DNA damage in cultured S30 breast cancer cells with the following order of potency: methyl caffeate (2) > caffeic acid (1) > ferulic acid (3) > cimiracemate A (9) > cimiracemate B (10) > fukinolic acid (5). These data suggest that black cohosh can protect against cellular DNA damage caused by reactive oxygen species by acting as antioxidants. 相似文献
95.
Evaluation of estrogenic activity of plant extracts for the potential treatment of menopausal symptoms 总被引:20,自引:0,他引:20
Liu J Burdette JE Xu H Gu C van Breemen RB Bhat KP Booth N Constantinou AI Pezzuto JM Fong HH Farnsworth NR Bolton JL 《Journal of agricultural and food chemistry》2001,49(5):2472-2479
Eight botanical preparations that are commonly used for the treatment of menopausal symptoms were tested for estrogenic activity. Methanol extracts of red clover (Trifolium pratense L.), chasteberry (Vitex agnus-castus L.), and hops (Humulus lupulus L.) showed significant competitive binding to estrogen receptors alpha (ER alpha) and beta (ER beta). With cultured Ishikawa (endometrial) cells, red clover and hops exhibited estrogenic activity as indicated by induction of alkaline phosphatase (AP) activity and up-regulation of progesterone receptor (PR) mRNA. Chasteberry also stimulated PR expression, but no induction of AP activity was observed. In S30 breast cancer cells, pS2 (presenelin-2), another estrogen-inducible gene, was up-regulated in the presence of red clover, hops, and chasteberry. Interestingly, extracts of Asian ginseng (Panax ginseng C.A. Meyer) and North American ginseng (Panax quinquefolius L.) induced pS2 mRNA expression in S30 cells, but no significant ER binding affinity, AP induction, or PR expression was noted in Ishikawa cells. Dong quai [Angelica sinensis (Oliv.) Diels] and licorice (Glycyrrhiza glabra L.) showed only weak ER binding and PR and pS2 mRNA induction. Black cohosh [Cimicifuga racemosa (L.) Nutt.] showed no activity in any of the above in vitro assays. Bioassay-guided isolation utilizing ER competitive binding as a monitor and screening using ultrafiltration LC-MS revealed that genistein was the most active component of red clover. Consistent with this observation, genistein was found to be the most effective of four red clover isoflavones tested in the above in vitro assays. Therefore, estrogenic components of plant extracts can be identified using assays for estrogenic activity along with screening and identification of the active components using ultrafiltration LC-MS. These data suggest a potential use for some dietary supplements, ingested by human beings, in the treatment of menopausal symptoms. 相似文献
96.
N. Pallais N. Fong R. Garcia J. Santos-Rojas 《American Journal of Potato Research》1990,67(2):109-119
Twelve true potato seed (TPS) crosses were tested for seedling vigor after 3 and 6 months of storage. Bulk seed was sown in the 3-month test, and high- and medium-density seed was sown in the 6-month test. Treatments consisted of pre-sowing in solutions of KNO3 + K3PO4 at -10 MPa for 5 days (priming), and in gibberellic acid at 1500 ppm (GA) or in water for 1 day; rinsed seed served as a control. In both the 3- and 6-month tests, seedlings of Atlantic x LT-7 (A1) outperformed all other crosses in rate of emergence and dry weight. Overall performance increased for all crosses when tested after 6 months of storage. In the 3-month test, the priming treatment increased seedling vigor in cross A1, otherwise, differences among treatments were mostly not significant. In the 6-month test, however, priming increased vigor in all crosses. Emergence generally was >80% in both tests. After 3 months, however, GA increased the percentage of emergence from ≤38% to 73% in the two least vigorous or most dormant crosses. Seed density levels were neither strongly nor consistently related to seedling vigor. The findings suggest that considerable improvement of TPS seedling performance can be attained by 1) selecting more vigorous or less dormant TPS progenies; 2) sowing seed after 6 months in storage; and (3) priming seed. 相似文献
97.
Reactive dye is a popular dye for dyeing cotton fiber due to its very good color fastness which is explained by the formation of covalent bond between dye and fiber. In this study, practicality of reuse of reactive dye by compensating for the hydrolyzed part of the dye solution is examined. A monofunctional dye (vinyl sulfone type) was used and it was found that dyeing cotton fiber with reused dyebath is possible. Since bifunctional dye can improve the chance of dye-fiber bond formation, vinyl sulfone based bifunctional reactive dyes were also selected in this study. Three types of bifunctional dyes were used and they basically share the same vinyl sulfone group; other reactive groups are monochlorotriazine, dichlorotriazine and vinyl sulfone. Such dyes were chosen in order to compare their respective efficiencies under the effect of one common reactive group. The aim of this study was to compare the effect of hydrolyzed and unhydrolyzed proportions of mono-and bifunctional reactive dyes on cotton fiber and study the possibility and efficiency of the two different reuse dyebath systems. 相似文献
98.
A combined water culture and pot culture technique was developed for the study of the K nutrition of potatoes. The water culture technique permitted control of the K nutrient supply while the pot culture technique provided support for plant growth and for tuber development in a low K medium. Both plant growth and tuber quality reflected the K supply of the culture solution. 相似文献
99.
María Botero Omary Christina Fong Jeffrey Rothschild Patrick Finney 《Cereal Chemistry》2012,89(1):1-14
There are a growing number of individuals diagnosed with food allergies and intolerances. Gluten, in particular, is avoided by many individuals because of celiac disease, gluten intolerance, and gluten ataxia. Individuals with allergies, intolerances, or both follow strict diets, but there is concern that these individuals may be at risk of several nutrient deficiencies, including decreased calcium, iron, B vitamins, and fiber. To prevent deficiencies, alternative sources of these nutrients must be provided. Gluten‐free cereals and pseudocereals such as amaranth, buckwheat, corn, millet, rice, sorghum, and quinoa can be excellent sources of vitamins, minerals, fiber, and other important nutrients. Germination of these edible seeds has been shown to further increase nutrient content and to reduce antinutrients. Their use to naturally fortify and enrich gluten‐free foods has great potential. Although there are many benefits to germinated seeds in food, more research must be done to improve texture and sensory properties to gain wider consumer acceptance. A review of germination of gluten‐free cereals and pseudocereals and its effect on their nutritional profile is presented. 相似文献