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41.
Hui Zhang Yu‐Jun Zhu Ye‐Yang Fan Ting‐Xu Huang Jian‐Fu Zhang Hua‐An Xie Jie‐Yun Zhuang 《Plant Breeding》2019,138(5):568-576
This study was conducted to identify new quantitative trait loci (QTLs) that have stable effects for eating and cooking quality (ECQ) of rice. Three recombinant inbred line populations of indica rice were each planted in two years. Three traits for ECQ, amylose content (AC), gel consistency (GC) and alkali spreading value (ASV), were measured for QTL analysis. A total of 13 QTLs were detected, including four for AC, six for ASV and three for GC. Two QTLs, qGC4 in the interval RM16252–RM335 on the short arm of chromosome 4 and qGC6.2 in the Alk region, were validated in a population derived from a residual heterozygote that was homozygous at the major locus Wx. In the absence of segregation at the Wx locus, qGC4 and qGC6.2 had additive effects of 2.46 and 8.18 mm, respectively, offering a potential for improving GC property of rice varieties. Comparison between qGC4 and previous results suggests that qGC4 is likely a new QTL for GC, providing a candidate for gene cloning and functional characterization. 相似文献
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Pregnancy Loss in Dairy Cattle: Relationship of Ultrasound,Blood Pregnancy‐Specific Protein B,Progesterone and Production Variables 下载免费PDF全文
G Gábor JP Kastelic Z Abonyi‐Tóth P Gábor T Endrődi OG Balogh 《Reproduction in domestic animals》2016,51(4):467-473
Objectives were to determine associations between percentage pregnancy loss (PPL) in dairy cattle and: (i) pregnancy diagnosis by ultrasonography; (ii) pregnancy diagnosis by serum pregnancy‐specific protein B (PSPB) concentrations, with or without serum progesterone concentrations; and (iii) production and environmental factors. This study included 149 822 pregnancy diagnoses conducted over 13 years in Holstein‐Friesian cows in Hungarian dairy herds. The following were determined: PPL in cows diagnosed pregnant by transrectal ultrasonography 29–42 days after artificial insemination (AI; n = 11 457); PPL in cows diagnosed pregnant by serum PSPB 29–35 days after AI (n = 138 365); and PPL and its association with serum progesterone concentrations, PSPB and production/environmental variables. The definition of PPL was percentage of cows initially diagnosed pregnant based on ultrasonography or PSPB, but not pregnant when examined by transrectal palpation 60 –70 days after AI. The PPL was lower (p < 0.001) in cows following ultrasonographic vs PSPB diagnosis of pregnancy at 29–35 days (8.1 vs 19.3%, respectively), but was higher in cows following ultrasonographic pregnancy diagnosis on 29–35 vs 36–42 days (8.1 vs 7.1%, respectively, P < 0.05). Furthermore, 72.9% of pregnancies with ultrasound‐detected morphological abnormalities resulted in pregnancy loss. As a subset of PSPB data, a fully quantitative PSPB assay was used for 20 430 samples; PPL in cows with a high PSPB concentration (>1.1 ng/ml) was lowest (15.0%), whereas cows with low concentrations of both PSPB and progesterone (0.6–1.1 and <2 ng/ml, respectively) had the highest PPL (76.3%; p < 0.0001). Furthermore, PPL was higher in cows with advanced parity and with high milk production, when ambient temperatures were high, although body condition score (BCS) had no effect on PPL. Finally, there were no significant associations between serum PSPB and environmental temperatures or number of post‐partum uterine treatments. 相似文献
44.
B. U. Metzler‐Zebeli W. R. Caine M. McFall B. Miller T. L. Ward R. N. Kirkwood R. Mosenthin 《Journal of animal physiology and animal nutrition》2010,94(2):237-249
Sixty‐four pigs from 16 sows were used to evaluate addition of zinc amino acid complex (ZnAA) to lactating sows and gastric nutriment‐intubation of zinc methionine (ZnMet) to suckling pigs on mineral status, intestinal morphology and bacterial translocation after weaning. Sows were fed a barley‐based diet supplying 120 ppm zinc (Zn; control) or the control diet supplemented with 240 ppm Zn from ZnAA. At birth, day‐10 and day‐21 (weaning) of age, pigs from each litter were nutriment‐intubated with 5 ml of an electrolyte solution without or with 40 mg Zn from ZnMet. At weaning, 24 h prior to the collection of small and large intestinal lymph nodes and sections of the duodenum, jejunum and ileum, the pigs received an intramuscular injection of saline without or with 150 μg/kg body weight of Escherichia coli O26:B6 lipopolysaccharide (LPS). With the exception of a tendency (p = 0.09) for lower serum concentration of copper in pigs at weaning from ZnAA‐supplemented sows, there were no differences (p > 0.1) than for pigs from control‐fed sows for mineral status or intestinal morphology. Nutriment‐intubation of ZnMet increased serum (p = 0.001) and liver (p = 0.003) Zn concentrations, number of goblet cells per 250 μm length of jejunal villous epithelium (p = 0.001) and tended (p = 0.06) to enhance jejunum mucosa thickness. Interactive effects (p < 0.05) for higher jejunal villi height and villi:crypt ratio and increased ileal goblet cell counts were apparent for pigs from ZnAA‐supplemented sows that also received nutriment‐intubation of ZnMet. Challenge with LPS increased (p = 0.05) ileal villous width. Nutriment‐intubation of ZnMet decreased (p = 0.05) anaerobic bacteria colony forming unit counts in the large intestinal mesenteric lymph nodes. In conclusion, nutriment‐intubation of ZnMet increased serum and liver tissue concentrations of Zn and resulted in limited improvement to intestinal morphology of weaned pigs. 相似文献
45.
Brooks HW White DG Wagstaff AJ Michell AR 《Veterinary journal (London, England : 1997)》1997,153(2):163-169
A high-calorie oral rehydration solution (ORS) with glutamine (n=11) was more effective in correcting plasma, extracellular fluid and blood volume than solutions without (one WHO-type solution, n=6, and two high-glucose but glutamine-free solutions, n=7, n=12). It was the only solution to improve plasma volume significantly within 48 h and sustain the improvement throughout treatment; similarly, it was the only solution to correct packed-cell volume within 48 h and sustain the benefit to the end of treatment. At the end of treatment, the glutamine-treated calves were the only ones to avoid a significant weight loss compared with their pre-diarrhoeic values. The crucial difference between this solution and those used with glutamine previously is that it gave significant nutritional support whereas WHO type solutions did not. It also had more favourable effects on hyponatraemia and metabolic acidosis than a standard ORS. Use of a high-calorie ORS for 4 days (rather than 2 days of 50:50 admixture with milk replacer) brought additional beneficial effects on blood glucose and body weight. 相似文献
46.
Marcial Arellano‐Martínez Bertha Patricia Ceballos‐Vázquez César Ruíz‐Verdugo Edgar Pérez de León Rafael Cervantes‐Duarte Pedro Martin Domínguez‐Valdéz 《Aquaculture Research》2011,42(4):571-582
The lion's paw scallop, Nodipecten subnodosus (Sowerby) has considerable aquacultural potential due to its fast growth and large adductor muscle. Prior investigations throughout northwestern Mexico's littoral have reported highly variable growth rates; furthermore, no studies are available of the environment on growth and gametogenesis in this species under culture conditions. This investigation assesses the effect of food availability and temperature on the growth and gametogenesis of N. subnodosus in a suspended culture system at Guerrero Negro lagoon, Mexico. After 1 year of cultivation, N. subnodosus reached 69.13 mm in shell height (SH) (0.196 mm day?1, 14 months old). Two significant growth spurts were observed: over the two first months of culture (August and September 2001, mean growth rate 0.4 mm day?1) and in September 2002 (0.3 mm day?1), both related to high temperatures and chlorophyll a concentrations. The onset of gametogenesis occurred in April 2002, with an increase in temperature (10‐month‐old scallops, 54.5 mm SH). The first spawning occurred in October and November (86.2 and 93 mm SH), with peak temperatures. These results, together with the analysis of previous reports, indicate that N. subnodosus has a higher preference for temperate areas; therefore, the Guerrero Negro lagoon appears to be a suitable site to culture this species. 相似文献
47.
Chaleow Salakij Jarernsak Salakij Kreangsak Prihirunkit Nual‐Anong Narkkong Decha Pitakkingthong 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2010,39(2):193-198
Background: The Leopard Cat (Prionailurus bengalensis) is the most frequently encountered wild cat in most of Southeast Asia. Limited hematologic investigation exists for this species. Objectives: The objectives of this study were to assess routine hematologic measurements and parameters and characterize the morphology, cytochemical staining, and ultrastructural features of blood cells in Leopard Cats. Methods: Blood samples were collected from 12 adult healthy captive Leopard Cats (7 males and 5 females). Complete blood counts were performed using an automated hematology analyzer and manual differential counts. Cytochemical staining (Sudan black B [SBB], peroxidase [PO], periodic acid‐Schiff [PAS], α‐naphthyl acetate esterase [ANAE], and β‐glucuronidase [BG]) and scanning and transmission electron microscopy were performed using standard methods. Results: Median (range) hematologic results were as follows: PCV 0.46 L/L (0.30–0.55 L/L), hemoglobin 136.5 g/L (100–183 g/L), WBC 9.0 × 109/L (6.9–15.2 × 109/L), band neutrophils 0.07 × 109/L (0–0.30 × 109/L), segmented neutrophils 2.9 × 109/L (1.2–6.34 × 109/L), lymphocytes 5.3 × 109/L (2.7–8.1 × 109/L), eosinophils 0.14 × 109/L (0–0.73 × 109/L), basophils 0/L (0–0.22 × 109/L), and monocytes 0.08 × 109/L (0–0.30 × 109/L). Neutrophils stained strongly positive for SBB, PO, and PAS; lymphocytes had fine granular positivity for ANAE and BG; monocytes were weakly positive for ANAE and BG; and basophils were strongly positive for BG. Ultrastructurally, eosinophils contained many large rod‐shaped granules with prominent crystalloid core structures, ribosomes, and mitochondria. Basophils contained many round to oval specific granules with homogeneous contents. Low number of basophils contained a few small vacuoles that usually were not detected by light microscopy. Conclusion: These findings will facilitate interpretation of hematologic results for future investigative and diagnostic studies of this species. 相似文献
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Soil organic matter (SOM) is a key property determining soil functions and a major form of carbon stored in soil. Understanding the spatial and temporal variability of SOM and the driving forces responsible for spatial and temporal changes is important to assess regional soil quality and carbon sequestration potential and, particularly, to establish better practices for land use and management. We evaluated the spatio‐temporal change in SOM content from 1979–1982 to 2006 and its driving forces in Jiangsu Province, East China, using geostatistics. The results showed that mean SOM content increased from 16.60 ± 8.50 to 18.31 ± 8.32 g/kg over a 26‐yr period. The maps of SOM generated by ordinary kriging represented the increasing trend from north to south across the province in the two periods. The level of SOM in 1979–1982 affected the pattern of change: the SOM increasing in areas initially with a small content while decreasing in areas having a large content. The map of SOM change showed that the rate of increase decreased from north to south within the province. Increased fertilizer application promoted crop production with more residual biomass being retained in the soil, which resulted in increased SOM content. Land use changes to paddy, upland or forest improved SOM content, whereas abandoning land reduced SOM content. 相似文献