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131.
The purpose of this review is to summarize the effectiveness, modes of action and commercial application of herbal plants and their derivatives as growth promoters for animal. Feed supplements
are a group of feed ingredients that can cause a desired animal response in a non-nutrient role such as pH shift, growth,
or metabolic modifier (Hutjens, 1991). Common feed additives used in animal diets include immunostimulators, antimicrobials, antioxidants, pH control agents and
enzymes. Herbal plants, are a new class of growth promoters and in recent years this feed additives have gained extensive
attention in the feed industry. They are a wide variety of herbs, spices, and products derived thereof, and are mainly essential
oils. Although numerous reports have demonstrated antioxidative and antimicrobial and immune stimulation efficacy in vitro, respective experimental in vivo evidence is still quite limited. A limited number of experimental comparisons of herbal plants feed additives with antibiotics
or organic acid have suggested similar effects on the animal gut microflora. Gut microflora has significant effects on host nutrition, health, and growth performance by interacting with nutrient utilization
and the development of gut system of the host. In addition, some phytogenic compounds seem to promote intestinal mucus production.
However, the future of using herbs in animal feeding will in great measure depend on the knowledge of chemical structure, their value and characteristics of practical herbs or their extract physiological needs and well-being of animal, and, above
all on consumer’s preferences and expectations. 相似文献
132.
Azari O Babaei H Derakhshanfar A Nematollahi-Mahani SN Poursahebi R Moshrefi M 《Veterinary research communications》2011,35(4):211-222
The aim of this study was to investigate the effects of transplanted Wharton’s jelly mesenchymal stem cells (WJMSCs) of caprine
umbilical cord on cutaneous wound healing process in goat. After collection of caprine pregnant uterus of mixed breed goats
from abattoir, the Wharton’s jelly (WJ) of umbilical cord was harvested. The tissues were minced in ventilated flasks and
explant culture method was used for separating mesenchymal stem cells (MSCs). The isolated cells were immunostained for Actin
protein, histochemically assayed for the presence of alkaline phosphatase activity, and analyzed for detection of matrix receptors
(CD44) and hematopoetic lineage markers (CD34), using flow cytometery. After The isolated cells, 3 × 106 MSCs were stained with BrdU and prepared for transplantation to each wound. Four 3-cm linear full thickness skin incisions
were made on both sides of thoracic vertebrate of four Raeini goats (two wounds on each side). The left wounds were implanted
with MSCs in 0.6 ml of Phosphate buffer saline (PBS), and the right wounds considered as control group that received 0.6 ml
of PBS. The samples were taken from the wounds 7 and 12 days after the wounding, and healing process was compared histologically
between the two groups. Anti-BrdU staining showed that the transplanted cells were still alive in the wound bed during the
study. The histopathological study revealed that re-epithelialization was complete at days 7 in treated wounds with WJMSCs,
whereas in control wound the wounds still showed incomplete epithelialization 12 days after wounding. Also, microscopic evaluation
showed less inflammation, thinner granulation tissue formation with minimum scar in the treated wounds in comparison with
control wounds. In conclusion, this study demonstrates the beneficial effect of caprine WJMSCs in cutaneous wound healing
in goat. 相似文献
133.
Aljumaah RS Almutairi FF Ayadi M Alshaikh MA Aljumaah AM Hussein MF 《Tropical animal health and production》2011,43(8):1605-1610
The purpose of this study was to determine the prevalence of subclinical mastitis in camels in Riyadh, Saudi Arabia and the
factors influencing its incidence. A total of 740 quarter milk samples were collected from 47 camel herds belonging to Majahim, Maghatir, Shu’l, and Sufer breeds. California mastitis test (CMT) was used as a screening test for subclinical mastitis. Samples giving negative or
trace CMT scores (0) were assigned to healthy quarters, while those giving positive scores of 1+ to 3+ were assigned to subclinically
affected quarters. Logistic regression was used to assess the association of breed, parity, and stage of lactation with the
prevalence of subclinical mastitis. Milk fat, protein, lactose, solid nonfat percentages and Na, Ca, and K concentrations
were compared in CMT-positive versus healthy quarters. One third (33%) of tested quarters had subclinical mastitis based on
CMT. The estimated probability of subclinical mastitis with the combined effects of breed, parity, and stage of lactation
ranged from 15.8% to 54.6%. The risk of subclinical mastitis increased significantly with parity and with the early stage
of lactation. The Shu’l breed had significantly higher prevalence of subclinical mastitis than other breeds. Significant decreases
in protein, lactose, and solid nonfat, Ca and K concentrations and increase in Na concentrations were associated with subclinical
mastitis. In conclusion, subclinical mastitis is prevalent in Saudi camels, and its incidence is influenced by breed, parity,
and stage of lactation. 相似文献
134.
135.
McCall JW Kramer L Genchi C Guerrero J Dzimianski MT Supakorndej P Mansour A McCall SD Supakorndej N Grandi G Carson B 《Veterinary parasitology》2011,176(4):361-367
The antifilarial effects of tetracycline drugs were first demonstrated when they were found to be highly effective against L(3) and L(4) of Brugia pahangi and Litomosoides sigmodontis in rodent models. Tetracyclines are also now known to have activity against microfilariae and adult Dirofilaria immitis, but assessment of their activity against larval and juvenile heartworms has not been reported previously. This study assessed the effects of doxycycline administered orally at 10mg/kg twice daily for 30-day periods at selected times during the early part of the life cycle of D. immitis in dogs with dual infections of D. immitis and B. pahangi. Twenty beagles were randomly allocated by weight to four groups of five dogs each. On Day 0, each dog was given 50 D. immitis L(3) and 200 B. pahangi L(3) by SC injection. Dogs received doxycycline on Days 0-29 (Group 1); Days 40-69 (Group 2); or Days 65-94 (Group 3). Group 4 served as untreated controls. Blood samples were collected for microfilariae counting and antigen testing. Necropsy for collection of adult heartworms and selected tissues were performed Days 218-222. Heartworms recovered were examined by immunohistology, conventional microscopy/transmission electron microscopy, and molecular biology techniques. No live heartworms were recovered from dogs in Group 1; dogs in Group 2 had 0 to 2 live worms (98.4% efficacy), and dogs in Group 3 had 0-36 live worms (69.6% efficacy). All control dogs had live adult heartworms (25-41). The live worms recovered from dogs in Groups 2 and 3 were less developed and smaller that worms from control dogs. Microfilariae were not detected in any dogs in Groups 1 and 2; one dog in Group 3 had 1 microfilariae/ml at necropsy. All control dogs had microfilariae at necropsy. One dog in Group 1 was antigen positive at one sampling (Day 166). One dog in Group 2 was antigen positive Days 196 and 218-222 and three dogs in Group 3 were antigen positive at one or more samplings All five control dogs were antigen positive at all three sampling times. These findings suggest that doxycycline at 10mg/kg orally twice daily for 30 days has efficacy against migrating tissue-phase larvae and juvenile worms and will delay or restrict microfilarial production. 相似文献
136.
Yongqiang Tan Gregg R. Davidson Chun Hwa See D. Chuck Dunbar John H. O’haver Stephanie Rice Danny W. Harrelson Mansour Zakikhani 《Water, air, and soil pollution》2006,177(1-4):169-181
Picric acid is an explosive historically produced and disposed at the Louisiana Army Ammunition Plant (LAAP) in northern Louisiana. The potential for natural degradation of picric acid was investigated by creating picric-acid slurries with four LAAP sediments of variable composition and monitoring for up to 98 days. The concentrations of picric acid decreased rapidly in all slurries during the first day, attributed to adsorption, followed by slower decreases in some samples due to degradation. Degradation in unsterilized slurries was nearly complete within 80 days for two of the four sediments. Increases in nitrite and nitrate concentration over time were proportional to the loss of picric acid and indicate that at least two of the three nitrite groups were removed from the picric acid molecule. The absence of significant concentrations of compounds with a mass greater than 100 amu in the final solutions suggests that all three nitrite groups were removed. No correlation was found between the degree of degradation and grain size, clay content, organic content, carbonate content, or a suite of element concentrations in the sediment. Degradation in sterilized samples was minimal for all sediment slurries, indicating microbial activity as the primary mechanism of degradation. 相似文献
137.
138.
Journal of Plant Diseases and Protection - The loss of important contact herbicides like paraquat opens opportunities for more potentially sustainable solutions demanded by consumers and... 相似文献
139.
Tea [Camellia sinensis (L.) O. Kuntze] is a highly phosphorus (P) deficiency-tolerant species, however, involving mechanisms have not been investigated so far. In this work, mechanisms for intrinsic efficiency of P utilization were studied in tea seedlings grown hydroponically without or with adequate P supply. The contribution of P reserve in cotyledons to the P nutrition of tea seedlings and the role of mature leaves were examined at two contrasting P supply levels in plants with intact or severed cotyledons. During three subsequent harvest intervals, distinct reduction of P content was observed not only in cotyledons, but also in the mature leaves, stem and roots of plants supplied with low P. In plants supplied adequately with P, in contrast, a continuous rise of P content was detected. It was concluded that the cotyledons of tea plants are a major source of P but not organic compounds for growth of the young seedlings. 相似文献
140.
Marder SR Gorman CB Tiemann BG Perry JW Bourhill G Mansour K 《Science (New York, N.Y.)》1993,261(5118):186-189
The solvent dependence of the second hyperpolarizability, gamma, of a variety of unsaturated organic compounds has been measured by third harmonic generation at 1907 nanometers. It is seen that the measured gamma is a function of solvent polarity. These solvent-dependent hyperpolarizabilities are associated with changes in molecular geometry from a highly bond-length alternated, polyene-like structure for a formyl-substituted compound in non-polar solvents, to a cyanine-like structure, with little bond-length alternation, for a dicyanovinyl-substituted compound in polar solvents. By tuning bond-length alternation, gamma can be optimized in either a positive or negative sense for polymethine dyes of a given conjugation length. 相似文献