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221.
Miguel Angel ANGEL Maria Antonia GIL Cristina CUELLO Jonatan SANCHEZ-OSORIO Jesus GOMIS Inmaculada PARRILLA Jordi VILA Ignacio COLINA Marta DIAZ Josep REIXACH Jose Luis VAZQUEZ Juan Maria VAZQUEZ Jordi ROCA Emilio A. MARTINEZ 《The Journal of reproduction and development》2014,60(5):371-376
This study aimed to evaluate the effect of recipient-donor estrous cycle synchrony on recipient reproductive performance
after nonsurgical deep-uterine (NsDU) embryo transfer (ET). The transfers (N=132) were conducted in recipients sows that
started estrus 24 h before (–24 h; N=9) or 0 h (synchronous; N=31), 24 h (+24 h; N=74) or 48 h (+48 h; N=18) after the
donors. A total of 30 day 5 morulae or day 6 blastocysts (day 0=onset of estrus) were transferred per recipient. The highest
farrowing rates (FRs) were achieved when estrus appeared in recipients 24 h later than that in the donors (81.1%), regardless
of the embryonic stage used for the transfers. The FR notably decreased (P<0.05) when recipients were –24 h asynchronous
(0%), synchronous (61.3%) or +48 h asynchronous (50%) relative to the donors. No differences in litter size (LS) and piglet
birth weights were observed among the synchronous and +24 h or +48 h asynchronous groups. While a +24 h asynchronous
recipient was suitable for transfers performed with either morulae (FR, 74.3%; LS, 9.2 ± 0.6 piglets) or blastocysts (FR,
84.6%; LS, 9.8 ± 0.6 piglets), a + 48 h asynchronous recipient was adequate for blastocysts (FR, 87.5%; LS, 10.4 ± 0.7
piglets) but not for morulae (FR, 30.0%; LS, 7.3 ± 2.3 piglets). In conclusion, this study confirms the effectiveness of the
NsDU-ET technology and shows that porcine embryos tolerate better a less advanced uterine environment if they are
nonsurgically transferred deep into the uterine horn. 相似文献
222.
EOS Batista GG Macedo RV Sala MDDV Ortolan MF Sá Filho TA Del Valle EF Jesus RNVR Lopes FP Rennó PS Baruselli 《Reproduction in domestic animals》2014,49(3):448-452
In Bos taurus cattle, antimullerian hormone (AMH) has been demonstrated to have a high degree of correlation with ovarian antral follicle count and the number of healthy follicles and oocytes. To document the correlation between the plasma concentration of AMH and follicular number in Bos indicus and Bos taurus heifers, Nelore (Bos indicus, n = 16) and Holstein heifers (Bos taurus, n = 16) had their ovarian follicular waves synchronized. After synchronization, ovarian antral follicular population (AFP) was evaluated three times at 60‐day (d) intervals (T‐120 d, 120 days before plasma AMH determination; T‐60 d, 60 days before; and T0, at the time of plasma AMH determination). The plasma AMH concentration was positively correlated with the number of ovarian follicles on the day of the follicular wave emergence in Bos indicus (Nelore) and Bos taurus (Holstein) heifers at each evaluation time (p < 0.05). The AFP was higher in Bos indicus (Nelore) than in Bos taurus (Holstein) heifers (p < 0.05). Similarly, the AMH concentration was higher in Bos indicus (Nelore) than in Bos taurus (Holstein) heifers (p < 0.0001). When heifers were classified as to present high or low AFP according to the mean of the AFP within each genetic group, high‐AFP heifers presented a greater (p < 0.0001) AMH concentration than low‐AFP heifers, regardless of the genetic group. In conclusion, the AFP is positively correlated with plasma AMH concentration in both Bos indicus (Nelore) and Bos taurus (Holstein) heifers. Furthermore, Bos indicus (Nelore) heifers presented both greater plasma AMH concentrations and AFP than Bos taurus (Holstein) heifers. 相似文献
223.
Ariadna Sitjà-Bobadilla Maria Jesus Pujalte Azucena Bermejo Esperanza Garay Pilar Alvarez-Pellitero & Jaume Pérez-Sánchez 《Aquaculture Research》2007,38(7):733-739
A pathological study was conducted on laboratory‐reared juvenile common dentex (Dentex dentex) suffering trickling and continuous mortalities. During a 3‐month period (October–December), water temperature, clinical signs and mortalities were recorded. Moribund or dead fish were examined for bacteria and parasites. Bacteria were isolated from head kidney and external ulcers, and samples from the gills, intestine, stomach, trunk kidney, gall bladder and liver were taken for histology. Cumulative mortality reached 73%, and 80% of fish examined were positive for bacteria (102 isolates). Vibrio splendidus was the most prevalent in head kidney (59.7%) and ulcers (88.9%), and it was frequently isolated as pure culture (74.7% and 100% respectively). This is the first report of this bacterium in association with mortality in common dentex. Vibrio scophthalmi was the second most prevalent bacterium (29.2%) and accounted for 63.6% of the mixed infections with V. splendidus, V. harveyi, Pseudoalteromonas spp. and other species were rarely isolated. No parasites were found in histological sections. Bacteria were frequently observed in the lumen of the intestine and stomach, destroying the epithelium. A cellular reaction was suggested by the high numbers of rodlet cells (RC) in the intestinal epithelium, and the abundance of eosinophilic granular cells (EGC) in the intestinal lamina propria. In the stomach, vacuolized cells containing unidentified debris, sometimes of crystalloid appearance, were very common. The high prevalence of V. splendidus in pure cultures and the absence of other aetiological agents suggest that V. splendidus is substantially involved in the registered mortalities, although the implication of V. scophthalmi and even of some nutritional factors cannot be discounted. 相似文献
224.
Gabriel Jesus Alves de Melo ;Viviani Gomes ;Camila Costa Baccili ;Luiz Alberto Luz de Almeida ;AntonioCezar de Castro Lima 《农业科学与技术》2014,(10):865-873
Somatic cell counts (SCCs) levels indicate the occurrence of infections in goat udders and are related to the productivity of goat milk, cheese and yoghurt. This work presents a segmentation method for counting somatic cells in goat milk images, intending to detect an infection known as mastiffs, which is the major cause of loss in dairy farming. The image segmentation procedure is devised by using the lab color space and the watershed transform. A large number of samples under variable preparation conditions are treated with the proposed method. A comparison between manual and the proposed technique is presented. Promising results indicates that video-microscopy systems may be employed to develop automated SCC for goat milk. 相似文献
225.
Maria Victoria Martinez-Toledo Belen Rodelas Victoriano Salmeron Clementina Pozo Jesus Gonzalez-Lopez 《Biology and Fertility of Soils》1996,22(1-2):131-135
The production of pantothenic acid and thiamine by Azotobacter vinelandii was studied in a chemically defined medium and a dialysed soil medium amended with different amounts of carbohydrate and NH
inf4
sup+
. Pantothenic acid and thiamine were produced in large amounts in the culture medium containing 2.0–5.0% glucose and 0.1–0.3% NH4Cl. The results showed that the liberation of these vitamins was increased under adiazotrophic conditions and with an excess of C source.Group of Environmental Microbiology, Department of Microbiology, Faculty of Pharmacy and Institute of Water Research, University of Granada, 18071 Granada, Spain. 相似文献
226.
Fermin Rivera Patricia Bonilla Sandra Soriano Jose Luis Reyes Fernando Lares Jesus Islas 《Water, air, and soil pollution》1987,32(3-4):397-406
A survey on Chromobacterium sp. and Flavobacterium sp. was conducted in a waste stabilization pond system at Santo Tomas Atzingo, State of Mexico. For this purpose methods for the isolation and identification of Chromobacterium sp. and Flavobacterium sp. from wastewater were developed and proved to be efficient. Such methods are the result of combining and modifying a series of previously reported techniques for this genera strains, but for environments different from wastewater. 相似文献
227.
Fermin Rivera Gisela Garcia Alfonso Lugo Elena Zierold Jesus Islas Elizabeth Ramirez Patricia Bonilla 《Water, air, and soil pollution》1986,28(1-2):185-198
A protozoological survey was performed to analyze the organisms of the subphylum Sarcodina Schmarda, present in waste stabilization ponds located at Santo Tomás Atzingo, México, from March to December 1981. The amoebae isolated were identified and counted. Several physicochemical parameters were also determined and correlated with the biological data. Thirteen amoebic species were isolated and identified: one definite pathogen, Entamoeba histolytica Schaudinn; three species that have shown pathogenic strains for humans: Acanthamoeba polyphaga Page, Acanthamoeba castellanii Douglas, and Naegleria sp. (Alexeieff) Calkins; two opportunist species: Entamoeba coli (Grassi) Casagrandi and Barbagallo, and Iodamoeba bühschlii (Von Prowazek) Dobell; and seven free-living amoebae: Acanthamoeba astronyxis Ray and Hayes, Amoeba proteus (Pallas) Leidy, Hartmannella exundans Page, Hartmannella vermiformis Page, Pelomyxa palustris Leidy, Vahlkampfia avara Page, and Vahlkampfia russelli Singh. A clear correlation between the number of amoebae and the temperature and alkalinity of the system was found. The removal capacity of the ponds for E. histolytica varied from 30 to 100% during the survey. The amoebae showed a succession in space and time in the system studied. 相似文献
228.
Aiello A Fattorusso E Imperatore C Irace C Luciano P Menna M Santamaria R Vitalone R 《Marine drugs》2011,9(6):1157-1165
Chemical analysis of the Mediterranean ascidian Polyandrocarpa zorritensis (Van Name 1931) resulted in the isolation of a series of molecules including two monoindole alkaloids, 3-indolylglyoxylic acid (3) and its methyl ester (4), 4-hydroxy-3-methoxyphenylglyoxylic acid methyl ester (1) and a new alkaloid we named zorrimidazolone (2). The structure of the novel compound 2 has been elucidated by spectroscopic analysis and bioactivity of all compounds has been investigated. Zorrimidazolone (2) showed a modest cytotoxic activity against C6 rat glioma cell line. 相似文献
229.
230.
Maria Filomena de Jesus Raposo Alcina Maria Miranda Bernardo de Morais Rui Manuel Santos Costa de Morais 《Marine drugs》2016,14(2)
In recent years, scientists have become aware that human microbiota, in general, and gut microbiota, in particular, play a major role in human health and diseases, such as obesity and diabetes, among others. A large number of evidence has come to light regarding the beneficial effects, either for the host or the gut microbiota, of some foods and food ingredients or biochemical compounds. Among these, the most promising seem to be polysaccharides (PS) or their derivatives, and they include the dietary fibers. Some of these PS can be found in seaweeds and microalgae, some being soluble fibers, such as alginates, fucoidans, carrageenans and exopolysaccharides, that are not fermented, at least not completely, by colonic microbiota. This review gives an overview of the importance of the dietary fibers, as well as the benefits of prebiotics, to human health. The potential of the PS from marine macro- and microalgae to act as prebiotics is discussed, and the different techniques to obtain oligosaccharides from PS are presented. The mechanisms of the benefits of fiber, in general, and the types and benefits of algal fibers in human health are highlighted. The findings of some recent studies that present the potential effects of prebiotics on animal models of algal biomass and their extracts, as well as oligo- and polysaccharides, are presented. In the future, the possibility of using prebiotics to modulate the microbiome, and, consequently, prevent certain human diseases is foreseen. 相似文献