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71.
Chen HH Chiang W Chang JY Chien YL Lee CK Liu KJ Cheng YT Chen TF Kuo YH Kuo CC 《Journal of agricultural and food chemistry》2011,59(12):6444-6452
Adlay has long been used in traditional Chinese medicine and as a nourishing food. The acetone extract of adlay hull had previously been demonstrated to possess potent antimutagenic activity. The aims of this study were to identify the antimutagenic constituents from adlay hull by using Ames antimutagenic activity-guide isolation procedures and to investigate their chemopreventive efficacies in cultured cells. The results demonstrated that six compounds showing great antimutagenic activity were identified by spectroscopic methods and by comparison with authentic samples to be p-hydroxybenzaldehyde, vanillin, syringaldehyde, trans-coniferylaldehyde, sinapaldehyde, and coixol. Two of them, trans-coniferylaldehyde and sinapaldehyde, exhibit relatively potent scavenging of DPPH radicals, inhibit TPA stimulated superoxide anion generation in neutrophil-like leukocytes, and induce Nrf2/ARE-driven luciferase activity in HSC-3 cells. Moreover, trans-coniferylaldehyde possesses cytoprotective efficacy against tert-butyl hydroperoxide-induced DNA double-strand breaks in cultured cells, and the chemopreventive potency induced by trans-coniferylaldehyde may be through the activation of kinase signals, including p38, ERK1/2, JNK, MEK1/2, and MSK1/2. In summary, we first identified six antimutagenic constituents from adlay hull. Among them, trans-coniferylaldehyde would be a highly promising agent for cancer chemoprevention and merits further investigation. 相似文献
72.
Shu‐Yun Chen Szu‐Chien Liu Tzu‐Chuan Lo Andi Wahyono Sz‐Yun Chen Hsin‐Mei Ku 《Plant Breeding》2014,133(2):291-297
Non‐pungent bell pepper (Capsicum annuum L.) lacks the cytoplasmic male sterility (CMS) nuclear restorer allele, Rf, and CMS cannot be employed in its F1 hybrid seed production. To demonstrate that the genic male sterility (GMS) system in non‐pungent bell pepper can be converted to the CMS male sterility system, the conversion of GMS to CMS for non‐pungent bell pepper line GC3 was conducted by introgression of S‐type cytoplasm and the Rf allele from tropical pungent donors. After morphological traits were evaluated, two lines from BC1F1 containing S‐type cytoplasm and four lines from BC2F2 containing Rf allele, phenotypically similar to GC3, were obtained and could be employed as CMS male sterile lines and restorer lines for non‐pungent bell pepper. Four molecular markers potentially linked to traits of interest were also evaluated in BC1F1 and BC1F2 populations. This is the first time that GMS has been successfully converted to CMS in bell pepper, a significant contribution for bell pepper hybrid seed production. 相似文献
73.
Long‐term Effects of Pyrethrin and Cyfluthrin,a Type II Synthetic Pyrethroid,Insecticide Applications on Bull Reproductive Parameters 下载免费PDF全文
JL Stewart CF Shipley FA Ireland VL Jarrell CL Timlin DW Shike TL Felix 《Reproduction in domestic animals》2016,51(5):680-687
The objectives of this study were to determine effects of cyfluthrin and pyrethrin spray products, used in combination with cyfluthrin topical and ear tag applications, on bull reproductive parameters over 18 weeks. Angus or Angus x Simmental bulls were randomly assigned to one of three treatment groups: (i) no exposure to pyrethrins/cyfluthrin (CONT; n = 10), (ii) cyfluthrin ear tag and topical applications (ET; n = 10), or (iii) cyfluthrin ear tag, topical, premise spray and pyrethrin fog spray applications (ET+S; n = 8). Bull body weight was measured every 3 week, and body condition score and scrotal circumference were recorded on weeks 0, 9 and 18. Semen and serum were collected every 3 weeks for sperm evaluation and testosterone measurement, respectively. There was a treatment × week interaction (p < 0.01) for sperm with primary defects; bulls in CONT group had a greater (p = 0.01) percentage of sperm with primary defects than bulls treated with insecticides at week 18. Overall and progressive sperm motility, normal sperm morphology, secondary sperm defects and serum testosterone concentrations changed (p < 0.01) over time in all bulls; however, treatment did not affect (p ≥ 0.13) any of these parameters. There were also no treatment effects (p ≥ 0.08) on bull body weight, body condition score or scrotal circumference. The use of pyrethrin‐ and cyfluthrin‐based insecticides, regardless of application, did not negatively affect reproductive parameters in beef bulls when administered over 18 weeks. 相似文献
74.
SUMMARY A haemagglutination inhibition assay was used to detect antibody to psittacine beak and feather disease virus in sera from wild sulphur crested cockatoos (Cacatua galerita), galahs (Eolophus roseicapillus), short-billed corellas (Cacatua sanguinea), eastern long-billed corellas (Cacatua tenuirostris) and other psittacine birds in New South Wales. The seroprevalence of psittacine beak and feather disease ranged from 41% to 94% in different flocks, indicating infection with the virus is widespread in wild populations. 相似文献
75.
CL SCHWARTZKOFF JR EGERTON† DJ STEWART‡ PR LEHRBACH§ TC ELLEMAN¶ PA HOYNE¶ 《Australian veterinary journal》1993,70(4):123-126
SUMMARY A multivalent footrot vaccine has been developed, containing pilus antigens produced in recombinant Pseudomonas aeruginosa and representing all nine serogroups of Dichelobacter (Bacteroides) nodosus commonly recognised in the field. The responses of sheep to the multivalent vaccine have been compared with those to monovalent vaccines representing only a single serogroup. Antigenie competition between serogroups occurred in sheep immunised with the multivalent formulation, but high levels of protection were still achieved. The study showed that in multivalent footrot vaccines, antigenic competition is predominantly due to the presence of a family of immunologically-related pilus antigens rather than to interference by extraneous proteins. 相似文献
76.
77.
CB Riley † DH Riedesel ‡ IR Dohoo† CL Hatfield† S Clinch† 《Veterinary anaesthesia and analgesia》2003,30(2):113-114
As a result of anatomic and physiologic differences, draft breeds may be at greater risk of developing anesthetic complications. The aim of the study was to evaluate and compare anesthetic management of draft (DR) and light (LT) horses. A case‐matched retrospective study of 371 clinical case records of DR (124 cases) and LT (247 cases) horses presented for general anesthesia between 1991 and 1998 was performed. Data were tabulated and comparisons were made using Student's t‐test (significance p < 0.05). Prior to induction, there were significant differences in mean body weight, rectal temperature, PCV, RBC, and serum TP concentration between DR and LT breeds. There were differences in mean doses of pre‐operative butorphanol (LT 21 µg kg?1; DR 17 µg kg?1), induction guaifenesin (LT 99 mg kg?1; DR 88 mg kg?1), and intraoperative ketamine (LT 0.35 mg kg?1; DR 0.56 mg kg?1) required. There were no significant differences in the mean doses of pre‐operative xylazine, detomidine, or induction barbiturate administered. The mean, average, and maximum concentrations of inspired halothane were significantly higher for DR than for LT horses. Draft horses received 33% less intraoperative IV fluids (8.2 mL kg?1 hour?1) than LT horses. Mean anesthetic duration, time to extubation, and standing recovery were not significantly different. Induction complications were not reported for either group. Rates of occurrence of intraoperative bradycardia, hypercarbia, hypoxemia, and metabolic acidosis (SBE, TCO2, and bicarbonate concentration) did not differ significantly. Average MAP was greater in DR horses, but neither the degree nor the mean duration of hypotension differed between DR and LT horses. Mean PaO2 was significantly lower in DR (246 mm Hg, 32.8 kPa) than in LT (305 mm Hg, 40.7 kPa) breeds. Draft horses were at greater relative risk of hypoventilation than LT horses. The greater MAP and requirement for halothane and intraoperative ketamine may indicate problems in achieving and maintaining a surgical plane of anesthesia. Draft horses may be at a greater risk of ventilation–perfusion mismatching. 相似文献
78.
Jyh-Horng Wu Yu-Tang Tung Chiou-Fung Chyu Shih-Chang Chien Sheng-Yang Wang Shang-Tzen Chang Yueh-Hsiung Kuo 《Journal of Wood Science》2008,54(5):383-389
The methanolic extract of the root of Garcinia multiflora and its derived soluble fractions, namely those soluble in ethyl acetate (EtOAc), n-butanol, and water, were screened for their antioxidant activities. Among them, the EtOAc-soluble fraction exhibited the
highest scavenging activity against the 1,1-dipheny1,2-picrylhydrazyl radical, the highest superoxide radical scavenging activity,
and the strongest reducing power. In addition, according to the bioactivity-guided isolation, 26 specific phytocompounds,
including 3 aromatics, 3 benzophenones, 3 flavonoids, 3 isocoumarins, 1 phloroglucinol, 6 steroids, and 7 xanthones, were
isolated from the EtOAc-soluble fraction and identified. Of these, 2,4,3′,4′-tetrahydroxy-6-methoxybenzophenone and 1,3,6,7-tetrahydroxyxanthone
were found to be the major bioactive constituents, present in the crude extract in concentrations of 3.9 and 15.6 mg/g, respectively.
These two compounds had similar antioxidant activities to (+)-catechin, a well-known antioxidant. 相似文献
79.
H. P. Ritzema Le Dinh Thinh Le Quang Anh Dang Ngoc Hanh Nguyen Viet Chien Trinh Ngoc Lan R. A. L. Kselik Bui Thi Kim 《Irrigation and Drainage Systems》2008,22(1):19-34
The irrigation and drainage systems in the Red River Delta in Vietnam were designed and constructed in the 1950s and 60s.
These systems are well established and provide water to virtually all of the irrigable land in the Delta. The land is cropped
intensively: on average just over two crops a year. The irrigation and drainage systems are complex: dual purpose channels
and pumping stations are used. In the 1990s, the systems were rehabilitated and upgraded. A review showed that irrigation
projects performed reasonably well, but the two core drainage projects performed less than anticipated. In the Red River Delta,
with its low elevations, drainage rather than irrigation is often the limiting factor affecting agricultural production. To
investigate these constraints in more detail, a participatory research study on the effectiveness of drainage was conducted
in two drainage areas in the Red River Delta. The study started with a participatory pre-investigation to identify and quantify
the constraints in the functioning of the drainage systems. Next, the drainage system was modelled and computer simulations
were used to develop conceptual designs to improve the functioning of the systems. Finally, recommendations to improve the
institutional capacity of the drainage system management were formulated, again in close cooperation with the stakeholders.
These recommendations cover a whole range of technical issues: small-scale improvements in the farmers’ fields, modifications
in the main and secondary drainage systems, including the control structures, up to recommendations to increase the efficiency
of the pumping stations. Next to these technical innovations, recommendations to reform the complex institutional setting
have been formulated. 相似文献
80.
Chien EY Liu W Zhao Q Katritch V Han GW Hanson MA Shi L Newman AH Javitch JA Cherezov V Stevens RC 《Science (New York, N.Y.)》2010,330(6007):1091-1095
Dopamine modulates movement, cognition, and emotion through activation of dopamine G protein-coupled receptors in the brain. The crystal structure of the human dopamine D3 receptor (D3R) in complex with the small molecule D2R/D3R-specific antagonist eticlopride reveals important features of the ligand binding pocket and extracellular loops. On the intracellular side of the receptor, a locked conformation of the ionic lock and two distinctly different conformations of intracellular loop 2 are observed. Docking of R-22, a D3R-selective antagonist, reveals an extracellular extension of the eticlopride binding site that comprises a second binding pocket for the aryl amide of R-22, which differs between the highly homologous D2R and D3R. This difference provides direction to the design of D3R-selective agents for treating drug abuse and other neuropsychiatric indications. 相似文献