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931.
Rosypal AC Troy GC Duncan RB Zajac AM Lindsay DS 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(6):802-809
Eight female beagles were infected with 1 x 10(7) (low dose, LD) or 2 x 10(8) (high dose, HD) promastigotes of a North American isolate of Leishmania infantum infantum (LIVT-1 strain) isolated from naturally infected Virginia Foxhounds. Two female beagles served as negative controls and 2 male beagles chronically infected (> 3 years) with Leishmania infantum chagasi were positive controls. Bone marrow (BM) and lymph node (LN) aspirates were collected every 6-8 weeks for cytologic evaluation, parasite culture, and polymerase chain reaction (PCR). Serum samples were collected monthly for determination of serologic responses by indirect fluorescent antibody test (IFAT) and diagnostic rK39 antigen. Cultures of BM and LN aspirates and cytology evaluation were consistently positive in positive control dogs during the course of study. Negative control dogs were negative on BM and LN cultures and on cytologic evaluation of aspirates. Amastigotes were present on cytological examination of BM aspirates in 2 experimentally infected dogs. Cultures of LN aspirates were positive on 22 samples, whereas BM cultures were positive on 12 samples for all dogs. IFA titers ranged from 0 to 1 :400 in experimentally infected dogs during the course of the study. Recombinant K39 immunoassay tests were consistently positive in positive control dogs and in the HD dogs by approximately 8 weeks after infection. BM PCR products were identified more consistently in the HD dogs compared with the LD dogs. Kappa statistics indicated PCR correlated better with cultures and cytology than did IFAT or the rK39 immunoassay results in the experimentally infected dogs. 相似文献
932.
Strip loins from two experiments were used to evaluate effects of feeding dry (DDG) or wet (WDG) distiller's grains on beef color, tenderness, and sensory traits of Holstein steers. In Exp. 1, conducted at the University of Illinois at Champaign-Urbana, dietary treatments consisted of a control whole corn-corn silage diet with soybean meal (SBM) or diets formulated with 12.5% DDG plus urea, 25% DDG, 25% WDG, 50% DDG, or 50% WDG (DM basis). In Exp. 2, conducted at Iowa State University, dietary treatments consisted of cracked corn-corn silage-hay diets with either SBM or urea (Urea) as the control diets, or diets formulated with 10, 20, or 40% DDG or WDG (DM basis). Within each study, strip loins from each of four steers (representing 45.7 and 66.6% of steers in Exp. 1 and 2, respectively) in four replicate pens per treatment were aged for 13 d at 4 degrees C for subsequent color, tenderness, and palatability evaluation. Color of steaks was measured objectively using a HunterLab Miniscan XE spectrophotometer and was subjectively evaluated by a trained panel. Tenderness was measured using the Warner-Bratzler shear force (WBSF) instrument on steaks cooked to 70 degrees C. For sensory evaluation, 95 consumers were recruited to evaluate tenderness, juiciness, and flavor of cooked steaks. In Exp. 1, steaks from steers fed 25% WDG had higher (P < 0.05) a* values after 138 h of simulated retail display than all other treatments, except for those from steers fed 12.5% DDG. In Exp. 2, a greater (P < 0.05) percentage of steaks from steers fed 40% DDG or 40% WDG were considered moderately undesirable during retail display (steaks that received a consumer acceptability score of 3 or less). There were no (P = 0.20 in Exp. 1, and P = 0.33 in Exp. 2) differences among treatments in Exp. 1 and Exp. 2 for WBSF (1.47 +/- 0.66 kg and 1.58 +/- 0.72 kg, respectively) or taste panel tenderness (5.7 +/- 0.30 and 6.2 +/- 0.22, respectively), beef flavor (6.0 +/- 0.23 and 6.2 +/- 0.22, respectively), and juiciness (5.6 +/- 0.31 and 5.8 +/- 0.23). Feeding distiller's grains at up to 50% of the dietary DM did not affect tenderness or sensory traits, and seems to be a viable feed alternative without negatively impacting sensory attributes. 相似文献
933.
The quantity of water available for irrigation is getting scarce in many countries and it assumes great importance for assured crop production, especially in view of the erratic behavior of the monsoon. Thus, there is a pressing need to improve the water efficiency of irrigation systems. One-way of improving the efficiency of the irrigation system is reusing the return flow from the irrigation system. This task requires quantification of return flow, which still remains as a grey area in irrigation water management. The estimation of return flow from the irrigation system is usually obtained using thumb rules depending upon the site-specific conditions like command area conditions and soil properties. In this paper, a hierarchical modeling technique, namely, regression tree is developed for return flow estimation. Regression tree is built through binary recursive partitioning. The effective rainfall, inflow, consumptive water demand, and percolation loss are taken as predictor variables and return flow is treated as the target variable. The applicability of the hierarchical model is demonstrated through a case study of Periyar-Vaigai Irrigation System in Tamil Nadu, India. The model performance shows a good match between the simulated and the field measured return flow values. Results of statistical analysis indicated that the correlation coefficients are high for both single as well as double crop seasons. 相似文献
934.
N. BHARATHAN W. R. GRAVES K. R. NARAYANAN D. J. SCHUSTER† H. H. BRYAN R. T. McMILLAN JR 《Plant pathology》1990,39(3):530-538
A disorder of unknown aetiology appearing as silvering on squash (Cucurbita pepo) leaves has become prevalent in south Florida. Typical symptoms, observed after 2 weeks of exposure to adults of Bemisia tabaci , the sweet potato whitefly (SPWF) include vein clearing followed by silvering of whole leaves. Fruits from affected plants are blanched or streaked longitudinally. The silverleaf syndrome was not mechanically transmissible when crude extracts of symptomatic leaves were used as inoculum. Two sizes of double-stranded RNA (dsRNA) of c. 4.6 and 4.2 kilobase pairs (kbp) were consistently observed in leaf extracts of caged, whitefly-infested, symptomatic plants. In contrast, caged plants not exposed to whiteflies showed no symptoms and contained no detectable dsRN A. In addition, squash plants exposed to SPWF colonies from California neither developed silverleaf symptoms nor contained any dsRNA. Double-stranded RNA could also be readily detected in whitefly-infested yellow summer squash and zucchini from the field. However, asymptomatic eggplant and watermelon infested with SPWF from nearby fields did not contain detectable dsRNA. Dot-spot hybridization assays using an RNA-specific probe detected homologous sequences in both adults and nymphs of SPWF that induced silverleaf symptoms but not in adults and nymphs of SPWF that could not induce silverleaf symptoms. These results, along with the non-endogenous nature of the detected dsRNA suggest that the dsRNA is or is associated with the causal agent of whitefly-mediated leaf silvering in squash. 相似文献
935.
Lina Maria Correa E Ricardo D. Moreno José Luis Riveros 《Anatomia, histologia, embryologia》2023,52(2):336-340
This is the first morpho-histological comparison of guanaco ovaries between reproductive (long-days) and non-reproductive (short-days) seasons, and oestrogen receptor-alpha (ERα) and beta (ERβ) detection. Different stages of follicle development were found in the cortical area, but no corpus luteum was detected. The size and frequency of antral follicles and large atretic follicles were higher in long-day ovaries than short-days, consistent with ovarian activity in this season. Differential expression of ERα and ERβ was observed in follicles at different stages of development between short and long days. These data reveal histological and molecular differences between reproductive and non-reproductive seasons of guanaco ovaries. 相似文献
936.
New evidence is presented to support the contention that the amoeba/cyst colonies isolated from surface-sterilized Spongospora subterranea f.sp. subterranea -infected potato tubers and spore balls have a saprophytic phase but are contaminants and not S. subterranea. Amoebae isolated from infected tissues and spore balls formed colonies associated with bacteria on 1% water agar at 18°C and encysted after 5–7 days. These cysts were morphologically distinct from the resting spores of S. subterranea and were formed singly or in a layer, unlike the spore ball (cystosorus) of S. subterranea . Amoebae, cysts and mixtures of amoebae and cysts in primary, secondary and tertiary subcultures failed to infect tomato roots. PCR amplification of DNA from amoebae, cysts and spore balls using the S. subterranea -specific primer pair SsF/R generated a 434-bp product from S. subterranea spore balls only and not from amoebae or cysts. When an amoeba/cyst-specific primer pair AmF/R was designed and used for PCR amplification, a single 411-bp product was generated from DNA of amoebae and cysts, but not from DNA of S. subterranea spore balls. These results are discussed in relation to earlier reports claiming the successful isolation of S. subterranea and other plasmodiophorids in vitro . 相似文献
937.
Calcium, magnesium, copper, inorganic phosphorus, sodium, potassium, total protein, albumin, globulin, urea, glucose, packed cell volume and haemoglobin in the bloods of apparently health single-suckler calves were frequently measured. Values were within normal ranges except magnesium and copper which became subnormal as lactation advanced and closely approached values of single-suckler calves clinically affected with combined hypomagnesaemic tetany and hypocuprosis which responded to magnesium and copper therapy.
Kurzfassung Die Autoren bestimmten häufig den Gehalt von Kalzium, Magnesium, Kupfer, anorganischem Phosphor, Natrium, Kalium, gesamtem Protein, Eiweiss, Globulin, Harnstoff, Glukose, Hämatokrit und Hämoglobin im Blut anscheinend gesunder Saugkälbern. Die bestimmten Werte lagen im je mehr die Laktation weiterschritt, und näherten sich den Werten von Saugkälbern, die von dem gleichzeitig auftretenden Magnesium und Kupfermangel im Blut verursachtem Starrkrampf befallen waren, und die auf eine Magnesium und Kupfer-Thermapie reagieriten.
Resume Le calcium, le magnésium, le cuivre, le phosphore inorganique, le sodium, le potassium, les proteines totales, les albumines, les globulines, l'urée, le glucose, le hématocrite et l'hémoglobine dans le sang de veaux allaités et apparemment en bonne santé ont été mesurés. Les valeurs no dépassaient pas les limites normales sauf dans le cas du magnésium et du cuivre, qui devenaient subnormales au fur et à mesure que la période de lactation avancait, pour se rapprocher aux valeurs des veaux allaités atteints cliniquement d'une combination de la tétanie hypomagnésémique et al l'hypocuperose que réagissent à une thérapie de magnésium et de cuivre.
Riassunto Gli autori hanno spesso definito il contenuto in calcio, magnesio, rame, fosforo inorganico, sodio potassio, proteina totale albumina, globulina, urea, glucosio, ematocrita, ed ematoglobulina del sangue di vitelli poppanti apparentemente sani. I valori erano normali eccetto quelli del magnesio e del rame che diventarono subnormali man mano che progrediva la lattaxione ed avvicinarono i valori dei vitelli lattanti clinicamente affetti dalla tetania ipomagnesemica combinata alla ipocuperosi e che rispondevano ad una terapia con magnesio e rame.相似文献
938.
Ana M. Guti��rrez Jos�� J. Cer��n Blas A. Marsilla Mar��a D. Parra Silvia Martinez-Subiela 《Canadian journal of veterinary research》2012,76(2):136-142
A new method was developed to simultaneously measure 2 acute-phase proteins (APPs) by time-resolved immunofluorometry. The assay, based on double-label quantification of haptoglobin (Hp) and C-reactive protein (CRP) in meat juice samples from pigs, was constructed by use of a combination of europium and samarium chelate lanthanides as labels. Meat juice samples from 154 pigs were used for analytic and clinical validation of the assay through determination of precision, accuracy, limit of detection, and quantification. The analytic performance of the assay was satisfactory, with good intra-assay and interassay precision and accuracy. The levels of Hp and CRP were increased in the meat juice samples of diseased animals compared with healthy ones. According to the results, higher sensitivity could be achieved if the cut-off values of both proteins were taken into account for clinical relevance rather than used individually. Since the dual assay saved both time and sample, it could be used as a rapid and sensitive screening test in porcine production. 相似文献
939.
Molina R Galina CS Maquivar M Estrada S Chávez A Díaz GS 《Veterinary research communications》2003,27(8):671-680
In order to evaluate the reproductive effect of a rotational breeding system, the pregnancy rate of 69 Zebu cows was assessed, 32 late postpartum (211±93 days postpartum, LP) and 37 early postpartum (averaging 63±8 days after calving, EP). In the LP group, 60% (19/32) were cycling before exposure to the bulls but only 38% (14/37) in the EP group. The two groups were dissimilar from the start (p<0.05). The cows were exposed in a rotational breeding system, with six Brahman bulls with previous sexual experience paired off in three groups (A–B, C–D and E–F). The cows were exposed to each pair of bulls for a period of 3 weeks, with one week in between each period, when the females were without the presence of a male. In the LP group, the pair of bulls A–B obtained a pregnancy rate of 72% (23/32), whereas for bulls C–D the pregnancy rate was 33% (3/9) and for bulls E–F the pregnancy rate was 67% (4/6). In contrast, for the EP cows, bulls A–B obtained a pregnancy rate of 32% (12/37), bulls C–D a pregnancy rate of 67% (12/18) and for bulls E–F a pregnancy rate of 55% (6/11). The percentage pregnancy obtained using the pair of bulls A–B differed (p<0.05) between LP and EP, whereas for bulls C–D and E–F it was similar. The pregnancy rate was different (p<0.05) in the first 3 weeks of mating for the LP group, the highest number of cows becoming pregnant during the first 3 weeks of the study. In contrast, the highest number of pregnancies in EP occurred evenly during the last 6 weeks. This study suggests that the reproductive performance of pairs of bulls in a 9-week rotational programme with the overall pregnancy rate is similar (94% in the LP and 81% in the EP). However, the time taken for the females to become pregnant, and hence the performance of the bulls, is related to the average number of days postpartum for the cows. 相似文献
940.