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71.
Hannah R. Leventhal Anna M. Hassebroek Francisco Carvallo Harold C. McKenzie 《Journal of veterinary diagnostic investigation》2021,33(6):1123
A 14-y-old pony mare was referred after 30-d duration of intermittent pyrexia, anorexia, weight loss, and change in manure consistency. Physical examination revealed a palpable but reducible ventral abdominal mass. Transabdominal ultrasonography revealed multiple distended, hypomotile, and thickened small intestinal loops in close approximation with numerous, well-defined, hyperechoic masses. There was a large amount of echogenic peritoneal fluid; abdominocentesis revealed a neutrophilic and macrophagic inflammatory exudate, and a mixed bacterial population was cultured. Given the poor prognosis, the mare was euthanized. The autopsy findings included a large abdominal abscess, serosanguineous peritoneal fluid with fibrin strands, and ~50 outpouches communicating with the lumen and extending from the anti-mesenteric aspect of the duodenum, jejunum, and ileum. These structures were classified as pseudodiverticula based on the histologic absence of the tunica muscularis layer of the intestinal wall. Pseudodiverticula should be included as a differential etiology in horses when clinical signs consistent with colic, diarrhea, or weight loss are recognized and, when on examination, one or more organized masses are palpated or visualized on transabdominal ultrasound, as well as visualization of small intestinal loops with thickened walls. 相似文献
72.
Soil moisture and water use by pastures and silvopastures in a sub-humid temperate climate in New Zealand 总被引:1,自引:1,他引:0
Soil moisture content from 0 to 2 m depth was monitored under 2–6 year old radiata pine (Pinus radiata) with three understoreys of bare ground, lucerne (Medicago sativa) and ryegrass/clover (Lolium perenne/Trifolium spp.) and under adjacent open-grown lucerne and ryegrass/clover pastures. By the fifth year soil moisture depletion/recharge
pattern under the trees alone was similar to that under open pasture and under trees with pasture understoreys. Maximum plant
available moisture storage was 207–223 mm in the top meter of this Templeton silt loam soil but only 69–104 mm at 1–2 m depth
where coarse textures often predominated. Lucerne reduced soil moisture content (SMC) to lower levels during drier summers
and extracted more water from 1 to 2 m depth than ryegrass/clover. Evapotranspiration (ET) during early summer when soil moisture
was high was close to the Penman potential evapotranspiration (E
p
), but the difference increased when SMC in the top meter dropped below 200 mm. The silvopasture treatments had higher ET
in winter than pasture alone but this was still less than E
p
. Soil moisture deficits (SMD) at the end of each summer were sufficiently large to require slightly higher than normal winter
rainfall and ET < E
p
to recharge the soil to field capacity before the next summer. The soil moisture results, taken together with root and growth
data, suggest that trees and understorey pastures are complementary in the first three or four growing seasons but this balance
subsequently declines in favor of the pine trees. Management options, to extend the period that understorey pastures are productive,
include reducing tree stockings, more vigorous pruning, using competitive understoreys and changing from pines to deciduous
trees. Research on new silvopastoral combinations is suggested. 相似文献
73.
Objective To examine the incidence of positive results in a complement fixation test (CFT) and enzyme-linked immunosorbent assay (ELISA) for Chlamydophila abortus in Australian sheep and how this incidence differs with state of origin, age, sex, breed and property. To examine the consequences in relation to rejection of breeder sheep for export.
Design Collection of blood samples from 891 sheep on 109 properties in southern Australia. All samples had a unique, coded property identification.
Procedure The samples were tested using the Institut Pourquier Chlamydophila abortus antibody ELISA (rELISA) and a CFT. Residual maximum likelihood analyses of the sample to positive ratio of the corrected optical density for the rELISA and generalised linear mixed model analyses of the CFT outcomes were carried out.
Results The sample to positive ratio of the corrected optical density values of the rELISA did not differ between sex, age, breed or state of origin, but differed greatly between properties. The CFT outcome did not differ between age, breed or state of origin, but differed greatly between properties and was more often positive with rams than with ewes.
Conclusion Positive outcomes to C. abortus antibody tests are very common in Australia. Rams have a particularly high incidence of positive results with the CFT. Rejection of sheep and property consignments is likely to be very common with all tests and situations examined except for the CFT (at 1:32 dilution) in ewes. 相似文献
Design Collection of blood samples from 891 sheep on 109 properties in southern Australia. All samples had a unique, coded property identification.
Procedure The samples were tested using the Institut Pourquier Chlamydophila abortus antibody ELISA (rELISA) and a CFT. Residual maximum likelihood analyses of the sample to positive ratio of the corrected optical density for the rELISA and generalised linear mixed model analyses of the CFT outcomes were carried out.
Results The sample to positive ratio of the corrected optical density values of the rELISA did not differ between sex, age, breed or state of origin, but differed greatly between properties. The CFT outcome did not differ between age, breed or state of origin, but differed greatly between properties and was more often positive with rams than with ewes.
Conclusion Positive outcomes to C. abortus antibody tests are very common in Australia. Rams have a particularly high incidence of positive results with the CFT. Rejection of sheep and property consignments is likely to be very common with all tests and situations examined except for the CFT (at 1:32 dilution) in ewes. 相似文献
74.
SL Walker RF Smith DN Jones JE Routly MJ Morris H Dobson 《Reproduction in domestic animals》2010,45(1):109-117
The objectives of the present study were to quantify the effects of a biological chronic stressor (lameness) on the duration and frequency of different oestrous behaviours in parallel with milk hormone profiles. Dairy cows 51.8 ± 1.4 days postpartum (n = 59), including 18 non‐lame control cows, were scored for lameness and closely observed for signs of oestrus having had their follicular phases synchronized by administration of gonadotrophin‐releasing‐hormone (GnRH) followed by prostaglandin F2α (PG) 7 days later. Lameness shortened the period when herd‐mates attempted to mount the lame cows (1.83 ± 0.69 h vs 5.20 ± 1.53 h; p = 0.042) but did not affect the overall duration of total behaviours (lame 12.3 ± 1.3 h vs non‐lame 15.2 ± 1.3 h). Lameness also lowered the intensity of oestrus [1417 ± 206 points (n = 18) vs 2260 ± 307 points (n = 15); p = 0.029]. Throughout the synchronized oestrous period, lame cows mounted the rear of herd‐mates less frequently (p = 0.020) and tended to chin rest less (p = 0.075). Around the period of maximum oestrous intensity, lameness also diminished the proportion of cows mounting the rear of another cow and chin resting (p = 0.048, p = 0.037, respectively). Furthermore, lame cows had lower progesterone values during the 6 days before oestrous (p ≤ 0.05). Fewer lame cows were observed in oestrus following PG (non‐lame 83%, lame 53%; p = 0.030); however, if prior progesterone concentrations were elevated, lame cows were just as likely to be observed in oestrus. In conclusion, following endogenous progesterone exposure, lameness shortens the period when herd‐mates attempt to mount lame cows but does not affect the incidence of oestrous. However, lame cows are mounted less frequently and express oestrus of lower intensity. This is associated with lower progesterone prior to oestrus but not with abnormal oestradiol or cortisol profiles in daily milk samples. 相似文献
75.
Daniel J Marshall Alice Hayward Dominic Eales Michael Imelfort Jiri Stiller Paul J Berkman Terry Clark Megan McKenzie Kaitao Lai Chris Duran Jacqueline Batley David Edwards 《Plant methods》2010,6(1):1-6
Background
The introduction of second generation sequencing technology has enabled the cost effective sequencing of genomes and the identification of large numbers of genes and gene promoters. However, the assembly of DNA sequences to create a representation of the complete genome sequence remains costly, especially for the larger and more complex plant genomes.Results
We have developed an online database, TAGdb, that enables researchers to identify paired read sequences that share identity with a submitted query sequence. These tags can be used to design oligonucleotide primers for the PCR amplification of the region in the target genome.Conclusions
The ability to produce large numbers of paired read genome tags using second generation sequencing provides a cost effective method for the identification of genes and promoters in large, complex or orphan species without the need for whole genome assembly. 相似文献76.
Rachel P. Atherton Martin O. Furr Harold C. McKenzie Anne M. Desrochers 《Journal of Equine Veterinary Science》2011,31(1):19-25
Colitis in the adult horse is a life-threatening clinical condition that can be caused by any of several enteric pathogens. This study was conducted to determine whether treating horses with plasma obtained from donors that were hyperimmunized against the common equine diarrheal pathogens Clostridium difficile, Clostridium perfringens, and Salmonella sp shortens the duration of diarrhea in acute colitis. To evaluate the efficacy of plasma treatment, 42 horses with acute onset of diarrhea were studied. Horses were enrolled if they were of age >1 year, duration of diarrhea at presentation was <72 hours, and they had not received equine plasma within the last 3 months. In addition, the serum cortisol concentrations of horses with acute diarrhea were studied.Horses were randomized to receive hyperimmunized plasma, control plasma (collected from nonimmunized horses), or no plasma therapy. Clinical parameters and fecal consistency were observed until resolution, discharge, or death, and complete blood counts (CBCs) and biochemical profiles were collected throughout the study. A total of 38 horses completed the study. The mean duration of diarrhea was 40.7 ± 9.8 (mean ± SEM) hours, 119.2 ± 56.1 hours, and 72.0 ± 24.5 hours for the hyperimmunized plasma, normal plasma (NP), and control groups, respectively. Using survival analysis techniques, this difference did not achieve statistical significance (P = .374). Serum cortisol was found to be increased in all horses at presentation and to decrease with time in all treatment groups. There was no difference in cortisol concentrations between the three treatment groups studied (P = .237). 相似文献
77.
The insulin‐like growth factor‐I (IGF‐I) is a key regulator of reproductive functions. IGF‐I actions are primarily mediated by IGF‐IR. The main objective of this research was to evaluate the presence of IGF‐I and IGF‐I Receptor (IGF‐IR) in stallion testicular tissue. The hypotheses of this study were (i) IGF‐I and IGF‐IR are present in stallion testicular cells including Leydig, Sertoli, and developing germ cells, and (ii) the immunolabelling of IGF‐I and IGF‐IR varies with age. Testicular tissues from groups of 4 stallions in different developmental ages were used. Rabbit anti‐human polyclonal antibodies against IGF‐I and IGF‐IR were used as primary antibodies for immunohistochemistry and Western blot. At the pre‐pubertal and pubertal stages, IGF‐I immunolabelling was present in spermatogonia and Leydig cells. At post‐pubertal, adult and aged stages, immunolabelling of IGF‐I was observed in spermatogenic cells (spermatogonia, spermatocyte, spermatid, and spermatozoa) and Leydig cells. Immunolabelling of IGF‐IR was observed in spermatogonia and Leydig cells at the pre‐pubertal stage. The immunolabelling becomes stronger as the age of animals advance through the post‐pubertal stage. Strong immunolabelling of IGF‐IR was observed in spermatogonia and Leydig cells at post‐puberty, adult and aged stallions; and faint labelling was seen in spermatocytes at these ages. Immunolabelling of IGF‐I and IGF‐IR was not observed in Sertoli cells. In conclusion, IGF‐I is localized in equine spermatogenic and Leydig cells, and IGF‐IR is present in spermatogonia, spermatocytes and Leydig cells, suggesting that the IGF‐I may be involved in equine spermatogenesis and Leydig cell function as a paracrine/autocrine factor. 相似文献
78.
Brummell DA Watson LM Pathirana R Joyce NI West PJ Hunter DA McKenzie MJ 《Journal of agricultural and food chemistry》2011,59(20):10987-10994
Methylselenocysteine (MeSeCys) is an amino acid derivative that possesses potent anticancer activity in animals. Plants that can tolerate growth on soils with high Se content, known as Se hyperaccumulators, do so by converting inorganic Se to MeSeCys by the enzyme selenocysteine methyltransferase (SMT). A cDNA encoding the SMT from a Se hyperaccumulator was overexpressed in tomato (Solanum lycopersicum). Transgenic plants were provided with selenite or selenate to the roots during fruit development, and liquid chromatography-mass spectrometry was used to show that MeSeCys accumulated in the fruit but not in the leaves. Depending on the transgenic line and Se treatment, up to 16% of the total Se in the fruit was present as MeSeCys. MeSeCys was produced more effectively from selenite on a percentage conversion basis, but greater accumulation of MeSeCys could be achieved from selenate due to its better translocation from the roots. MeSeCys was heat stable and survived processing of the fruit to tomato juice. 相似文献
79.
Fletcher MT Brock IJ Reichmann KG McKenzie RA Blaney BJ 《Journal of agricultural and food chemistry》2011,59(9):5133-5138
Austral bracken Pteridium esculentum contains three unstable norsesquiterpene glycosides: ptaquiloside, ptesculentoside, and caudatoside, in variable proportions. The concentration of each of the glycosides was determined in this study as their respective degradation products, pterosin B, pterosin G and pterosin A, by HPLC-UV analysis. Samples of P. esculentum collected from six sites in eastern Australia contained up to 17 mg of total glycoside/g DW, with both ptaquiloside and ptesculentoside present as major components accompanied by smaller amounts of caudatoside. Ratios of ptaquiloside to ptesculentoside varied from 1:3 to 4:3, but in all Australian samples ptesculentoside was a significant component. This profile differed substantially from that of P. esculentum from New Zealand, which contained only small amounts of both ptesculentoside and caudatoside, with ptaquiloside as the dominant component. A similar profile with ptaquiloside as the dominant glycoside was obtained for Pteridium aquilinum subsp. wightianum (previously P. revolutum ) from northern Queensland and also P. aquilinum from European sources. Ptesculentoside has chemical reactivity similar to that of ptaquiloside and presumably biological activity similar to that of this potent carcinogen. The presence of this additional reactive glycoside in Australian P. esculentum implies greater toxicity for consuming animals than previously estimated from ptaquiloside content alone. 相似文献
80.