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81.
Tropical Animal Health and Production - We evaluated the relationship between the temperature–humidity index (THI) and health and growth performance in Japanese black calves in Japan. Data...  相似文献   
82.
A 42-day-old heavy draft horse fell into sudden astasia. Significant swelling and heat sensation of the left femoral region were observed. Because of a friction sound in the left hip, we supposed that the hip joint was dislocated or the hip bone was fractured. Computed Tomography (CT) examination showed that the left hip joint was dislocated and the left femoral head was disjunct. We carried out a pathological autopsy, and made a diagnosis of the foal as fracture of the hip bone and femoral head with suppurative umbilical arteritis. Pathologic changes in the umbilical artery and hind leg were completely unilateral, suggesting that left umbilical arteritis spread to the blood circulation, causing arthritis and dislocation of the hip bone.  相似文献   
83.
The vector competence of Frankliniella occidentalis for Chrysanthemum stem necrosis virus (CSNV) was evaluated. Three vector strains with distinct competences for Tomato spotted wilt virus (TSWV) transmission were investigated, including an artificially selected strain (TsH) that has a particularly high competence (>90 %). Newly hatched larvae of F. occidentalis were given an acquisition access period of 5 days on CSNV-infected D. stramonium leaves, and reared to maturity. Their transmission efficiencies were examined using a leaf disk assay using Petunia x hybrida leaves. Following the leaf disk assay, the virus accumulation in the vectors was examined via a double antibody sandwich enzyme-linked immunosorbent assay (DAS-ELISA) of their bodies. The results showed that the CSNV acquisition and transmission efficiency of the TsH strain did not differ from those of the others, indicating that the competence of F. occidentalis as a vector for CSNV is not related to that for TSWV. The CSNV transmission and acquisition efficiencies of two F. intonsa strains (Hiroshima and Fukuoka) were also evaluated. In Hiroshima strain, 35 % of adults were viruliferous, but only two transmitters (3 %) were observed. In Fukuoka strain, 6 % were viruliferous, and no transmitters were observed. These results indicate that F. intonsa cannot be a major vector for CSNV. The accumulation of CSNV in the adults of F. occidentalis and F. intonsa evaluated using DAS-ELISA showed a significant difference in ELISA values among transmitter, viruliferous non-transmitter, and non-viruliferous individuals. These results clearly demonstrated that only transmitters that accumulated a threshold quantity of virus can transmit CSNV to plants.  相似文献   
84.
A 4-year-old, intact male Shiba dog was referred to Yamaguchi University Animal Medical Center, Yamaguchi, Japan, for the following complaints: anorexia, lethargy, intermittent fever, gingival bleeding and abdominal purpura. The dog presented with persistent neutropenia. Histopathological examination of a bone marrow sample revealed round to oval structures that resembled Hepatozoon micromerozoites and formed a "wheel-spoke" pattern. Furthermore, mature neutrophils were observed around these structures. PCR and sequencing using bone marrow aspirate confirmed Hepatozoon canis (H. canis) infection. These findings suggest that the neutropenia observed in this case was associated with osteomyelitis due to H. canis infection. This is the first report of neutropenia associated with H. canis infection. H. canis infection can be included in the differential diagnosis in canine cases of neutropenia in areas where the disease is endemic.  相似文献   
85.
86.
There is increasing evidence for the presence of cancer stem cells in several solid tumors, and these cancer stem cells have a potential role in tumor initiation, aggression, and recurrence. The stem cell-like properties of spheres derived from canine mammary tumors remain largely elusive. We attempted to induce sphere formation using four cell lines of canine mammary adenocarcinoma, and characterized the spheres derived from a CHMp line in vitro and in vivo. The CHMp-derived spheres showed predominantly CD44+CD24 population, higher expression of stem cell-related genes, such as CD133, Notch3 and MDR, and higher resistance to doxorubicin compared with the CHMp-derived adherent cells. Xenograft transplantations in nude mice demonstrated that only 1 × 104 sphere cells were sufficient for tumor formation. Use of the sphere assay on these sphere-derived tumors showed that sphere-forming cells were present in the tumors, and were maintained in serial transplantation. We propose that spheres derived from canine mammary adenocarcinoma cell lines possess a potential characteristic of cancer stem cells. Spheres derived from canine mammary tumors could be a powerful tool with which to investigate novel therapeutic drugs and to elucidate the molecular and cellular mechanisms that underlie tumorigenesis.  相似文献   
87.
Sweet wheat (SW), which lacks functional granule-bound starch synthase I (GBSSI) and starch synthase IIa (SSIIa), accumulates high levels of free sugars in immature seeds. Here, we examined the effects of the lack of these two enzymes on mature kernel composition. Whole grain flour of SW had higher levels of sugars, particularly maltose, slightly higher ash and protein content, approximately two to three times higher lipid levels, and about twice as much total dietary fiber as parental or wild-type lines. Considerably higher levels of low-molecular-weight soluble dietary fiber (LMW-SDF), largely consisting of fructan, were also detected in SW. Although there were no differences in total amino acid levels, the free amino acid content of SW was approximately 4-fold higher than that of wild type, and the levels of certain free amino acids such as proline were particularly high. Thus, we were able to clearly demonstrate that the lack of GBSSI and SSIIa caused dramatic changes in mature seed composition in SW. These compositional changes suggest that SW flour may provide health benefits when used as a food ingredient.  相似文献   
88.
Uptake and elimination of aflatoxins (AFs) by rainbow trout ( Oncorhynchus mykiss ) during a long-term (21 days) dietary exposure were studied to assess contamination by AFs in aquaculture fish fed AF-containing feed. The uptake factor (UF) of aflatoxin B(1) (AFB(1)) in muscle ranged from 0.40 × 10(-3) to 1.30 × 10(-3). AFB(1) concentrations in liver were 165-342 times higher than in muscle. AFs from feed were more highly accumulated in liver than in muscle. Aflatoxicol (AFL) and aflatoxin M(1) (AFM(1)) were detected in muscle and liver and also in the rearing water. AFL concentrations were higher than AFM(1) by 2 orders of magnitude in muscle, and AFL was a major metabolite of AFB(1). The elimination rate constants (α) of AFB(1) and AFL in muscle (1.83 and 2.02 day(-1), respectively) and liver (1.38 and 2.41 day(-1), respectively) were very large. The elimination half-life (t(1/2)) of AFB(1) was 0.38 days (9.12 h) in muscle and 0.50 days (12.00 h) in liver. The elimination half-life of AFL in muscle and liver was 0.34 day (8.16 h) and 0.29 day (6.96 h), respectively. These data show that AFs are eliminated rapidly and are not biomagnified in fish. Thus, AFB(1) concentration in muscle of fish fed AFB(1)-containing feed (ca. 500 μg/kg) decreased to below the detection limit (20 ng/kg) of the most sensitive analytical method at 1.54 days (36.96 h) after the change to uncontaminated feed.  相似文献   
89.
Although climate conditions primarily determine the distribution and functioning of vegetation, vegetation also influences climate via biophysical and biogeochemical features such as evapotranspiration, albedo, carbon cycling, trace gas emissions and the roughness of the land surface. Forecasts of rapid climate change during the next 100~200 years, fueled by an increase in greenhouse gases, have motivated the development of land surface models (LSMs) that predict changes in vegetation functions. Here, we review how these models have been developed and used to simulate interactive processes between climate and the land surface. Current limitations and future perspectives of the LSMs are also presented.  相似文献   
90.
Summary Gamma-rays from a60Co source were applied to dry, ‘true’ seed from the cross ofSpartaan × Maris Piper and the segregation rations for various characters were investigated. The treatment affected the segregation ratios for stem colour, tuber shape, net skin, and vein necrosis; also possibly affected were maturity and number of primary leaflets. Ratios for depth of eye, leaf index and secondary growth of tubers were not changed. The changes in segregation ratios may be due to mutations and/or chromosome aberrations. Most of the changes in segregation ratios are suggested to be due to an increase in the frequency of nulliplex genotypes. The mutation rates estimated from the segregation ratios ranged from 2.0×10−6 to 10.9×10−6 per R.
Einfluss der Gammabestrahlung auf die Aufspaltungsverh?ltnisse in Zuchfamilien bei der Kartoffel
Zusammenfassung Trockene Samenk?rner aus der KreuzungSpartaan Maris Piper wurden mit Gammastrahlen60Co in Dosen von 2, 4, 8, 16, 32 und 64 krad behandelt und die Aufspaltungsverh?ltnisse für verschicdene Merkmale untersucht. Die Keimungs- und Reproduktionsraten für die verschiedenen Dosen sind in Abb. I dargestellt. Als Reproduktionsrate wird das Verh?ltnis der Anzahl knollentragender Pflanzen zur Gesamtanzahl überlebender Pflanzen bezeichnet. RD50 der Reproduktionsrate war ungef?hr 40 krad. Die H?ufigkeit mangelhafter Pflanzen wurde durch die Bestrahlung erh?ht (Tabelle 1). Die Behandlung beeinflusste die Aufspaltungsverh?ltnisse in der Stengelfarbe (Tabelle 2), Knollenform (Tabelle 3), Netzzeichnung der Schale (Tabelle 5) und Adernnekrose (Tabelle 8). M?glicherweise wurden auch die Reife (Tabelle 9) und die Zahl der prim?ren Fiederbl?ttchen (Tabelle 6) ver?ndert. Die Verh?ltnisse für die Augentiefe (Tabelle 5), Fiederbl?ttchenform (Tabelle 7) und die Kindelbildung der Knollen (Tabelle 5) wurden nicht ver?ndert. Die H?ufigkeit ph?notypischer rezessiver Erscheinungen wurde durch die Behandlung bei einigen Merkmalen. wie z.B. Netzeeichnung der Schale (Tabelle 5). Anzahl Fiederbl?ttchen (Tabelle 6) und Schalenfarbe (Tabelle 4), significant verringert. Die Aenderung in den Aufspaltungsverh?ltnissen dürfte auf Mutationen und/oder Chromosomen-Abweichungen zurückzuführen sein. Man vermutet, dass die meisten Aenderungen in den Aufspaltungsverh?ltnissen auf ein Ansteigen der H?ufigkeit von nulliplexen Genotypen zurückgehen. Die Sch?tzung der Mutationsraten auf Grund der Aufspaltungsverh?ltnisse bewegt sich zwischen 2.0 · 10−6 und 10.9 · 10−6 pro R (Tabelle 10).

Effects de rayons gamma sur les rapports de ségrégation dans des familles de ponne de terre
Résumé On a appliqué des rayons gamma émis par le cobalt 60 à des doses de 2, 4, 8, 16, 32 et 64 krad à des semences sèches provenant du croisementSpartaan. Maris Piper et on a recherché les rapports de ségrégation de différents caractères. La Figure I donne les taux de germination et de reproduction pour les différentes doses. Le taux de reproduction est défini par le rapport de nombre de plantes qui tubérisent au nombre total de plantes survivant. RD50 du taux de reproduction est d'environ 40 krad. L'irradiation accroit la fréquence de plantes déficientes (Tableau 1). Le traitement influence les rapports de ségrégation pour la couleur de la tige (Tableau 2) la forme du tubercule (Tableau 3). la peau réticulée (Tableau 5) et la nécrose des nervures (Tableau 8). II est possible que soient également influencées la maturité (Tableau 9), ainsi que le nombre de folioles primaires (Tableau 6). Ne sont pas modifiés les rapports pour la profondeur des yeux (Tableau 5) la forme des folioles (Tableau 7) et la croissance secondaire des tubercules (Tableau 5). La fréquence de phénotypes récessifs est significativement abaissée par le traitement pour quelques caractères tels que peau réticulée (Tableau 5). nombre de folioles latérales (Tableau 6) la couleur de la peau (Tableau 4). Les changements dans les rapports de ségrégation peuvent être dus à des mutations ou à des aberrations chromosomiques. On pense que la plupart des changements dans les rapports de ségrégation sont dus à une augmentation de la fréquence de génotypes nulliplex. Les taux de mutations estimés à partir des rapports de ségrégation varient de 2.0 · 10−6 à 10.9 · 10−6 par R (Tableau 10).
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