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排序方式: 共有222条查询结果,搜索用时 218 毫秒
61.
Renan B. Paiano Jeannine Bonilla Andrea M. Moreno Pietro S. Baruselli 《Reproduction in domestic animals》2021,56(12):1536-1542
The aim of this study was to identify the impact of Trueperella pyogenes in cows with clinical endometritis (CE) on reproductive performance and milk production in affected cows. In total, 230 lactating Holstein dairy cows from six commercial dairy herds were sampled once between 28 and 33 days post-partum. Cows included in the present study did not receive antibiotic or anti-inflammatory treatments prior to the experimental period. Clinical endometritis (CE) was characterized as cow with vaginal mucus score = 3 (>50% of purulent vaginal discharge) and >18% polymorphonuclear neutrophilic leukocyte (PMNL). The body condition scores (BCS) and milk production were evaluated at the time of enrolment. The identification of isolated bacteria was carried out through the analysis of MALDI-TOF MS (matrix-assisted laser desorption ionization time-of-flight mass spectrometry). According to uterine health, three groups of dairy cows were formed: healthy control cows without T. pyogenes (n = 147), CE cows with T. pyogenes (n = 22) and CE cows without T. pyogenes (n = 61). CE cows with T. pyogenes had lower BCS, milk production and conception at first AI (p < .01) than CE cows without T. pyogenes and control cows. Furthermore, CE cows with T. pyogenes had higher (p < .01) service per pregnancy and had greater (p < .01) days to get pregnant than CE cows without T. pyogenes and control cows. This study demonstrates that CE cows with T. pyogenes had impaired reproductive performance and milk production when compared to cows without CE and CE cows without T. pyogenes. This information can contribute to a strategic treatment in cows affected by clinical endometritis, favouring the rational use of antibiotics on dairy farms. 相似文献
62.
Enrico Bottero Emanuele Mussi Fabiano Raponi Davide De Lorenzi Pietro Ruggiero 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(7):736
This study describes the clinical, diagnostic, and pathological characteristics of canine nasal polyps and how they responded to medical, endoscopic, and surgical treatments. The database of a multi-center veterinary endoscopy group was searched from 2010 to 2018. All dogs with a histological diagnosis of nasal polyposis that were undergoing endoscopic investigation (N = 23), were included. Clinical signs at presentation were sneezing (91%), nasal discharge (83%), stertor (74%), and frontonasal deformation (17%). Skull radiography on 13 dogs had alterations in 77% of cases, including turbinate lysis (6/13), increased radiopacity of one (4/13) or both (6/13) nasal cavities, and lysis of the nasal vomer bone (3/13). Nasal polyposis had a characteristic endoscopic appearance. There were clinical and diagnostic similarities between this cohort of dogs and dogs with nasal neoplasia, although dogs with nasal polyps were often younger and polypoid tissue was external to the nose. Steroid therapy alone was not effective in treating polyposis in dogs; however, endoscopic debulking with a laser and forceps was more effective. 相似文献
63.
Stefania Colombini Andrea Rota Graziosi Pietro Parma Marcello Iriti Sara Vitalini Chiara Sarnataro Mauro Spanghero 《动物营养(英文)》2021,7(1):224
This study investigated the effects of 2 Achillea moschata essential oils extracted from plants collected in 2 different valleys of the Italian Alps and 3 pure compounds of oils — bornyl acetate (BOR), camphor (CAM), and eucalyptol (EUCA) — on in vitro ruminal fermentation and microbiota. An in vitro batch fermentation experiment (Exp. 1) tested the addition of all of the substances (2 essential oils and 3 compounds) in fermentation bottles (120 mL) at 48 h of incubation, whereas a subsequent in vitro continuous culture experiment (Exp. 2) evaluated the pure compounds added to the fermenters (2 L) for a longer incubation period (9 d). In both experiments, total mixed rations were incubated with the additives, and samples without additives were included as the control (CTR). Each treatment was tested in duplicate and was repeated in 3 and 2 fermentation runs in Exp. 1 and 2, respectively. Gas production (GP) in Exp. 1 was similar for all of the treatments, and short chain volatile fatty acid (SCFA) production was similar in both experiments except for a decrease of SCFA produced (P = 0.029) due to EUCA addition in Exp. 2. Compared to CTR, BOR and CAM reduced the valerate proportion (P = 0.04) in Exp. 1, and increased (P < 0.01) the acetate proportion in Exp. 2. All treatments increased (P < 0.01) total protozoa counts (+36.7% and +48.4% compared to CTR on average for Exp. 1 and 2, respectively). In Exp. 1, all of the treatments lowered the Bacteroidetes and Firmicutes and increased the Proteobacteria relative abundances (P < 0.05), whereas in Exp. 2, the EUCA addition increased (P = 0.012) the Ruminococcus. In Exp. 1, methane (CH4) as a proportion of the GP was lowered (P = 0.004) by the addition of CAM and EUCA compared to CTR, whereas in Exp. 2, EUCA reduced the amount of stoichiometrically calculated CH4 compared to CTR. Overall, essential oils extracted from A. moschata and the pure compounds did not depress in vitro rumen fermentation, except for EUCA in Exp. 2. In both experiments, an increase of the protozoal population occurred for all the additives. 相似文献
64.
Pietro Perrino Margaret Yarwood Peter Hanelt G. Battista Polignano 《Genetic Resources and Crop Evolution》1984,32(4):103-122
Summary The variability of 19 seed characters has been examined for 52 species of the genusVicia. Seed circumference, relative hilum length, hilum shape and lens position could be confirmed as the most relevant characters for grouping. By cluster analyses based upon them the material has been classified into 11 groups. Discriminant analyses gave 25 % misclassifications when all 19 variables were subjected to the analysis for the determination of individual seeds. A key for determination of the species has been proposed mainly by means of quantitative seed characters; dendrograms illustrate the result of the cluster analyses and seed diagrams show schematically important seed characters.
Die Variabilität von Samenmerkmalen bei ausgewähltenVicia-Arten
Zusammenfassung Es wurde die Variabilität von 19 Samenmerkmalen bei 52 Arten der GattungVicia geprüft. Für eine Gruppenbildung bestätigten sich dabei der Samenumfang, die relative Nabellänge, die Nabelform und die Lage der Chalaza als besonders geeignet. Bei einer auf diesen Merkmalen aufbauenden Cluster-Analyse konnten innerhalb des Untersuchungsmaterials 11 Artengruppen ausgeschieden werden. Diskriminanz-Analysen unter Verwendung von allen 19 Variablen ergaben eine Fehlklassifikation beim Versuch der Zuordnung einzelner Samen in 25 % der Fälle. Ein Schlüssel zum Bestimmen der Arten vorzugsweise an Hand von quantitativen Samenmerkmalen wurde vorgeschlagen. Dendrogramme illustrieren die Ergebnisse der Cluster-Analysen und schematische Samendiagramme die Ausprägung der relevanten Samenmerkmale.
Vicia
19 52 Vicia. : , , . , , 11 . , 19 25 % . , . , — .相似文献
65.
66.
Mattoli L Cangi F Maidecchi A Ghiara C Tubaro M Traldi P 《Journal of agricultural and food chemistry》2005,53(26):9860-9866
Immature bitter orange fruit and its extracts have been introduced into the market as an alternative to Ephedra in weight loss products. However, the safety of the immature bitter orange fruit and its extracts is a debated argument due to the presence of synephrine, a constituent known as a sympathomimetic agent. In this paper, we describe the development of a new, rapid, and simple liquid chromatography-electrospray ionization-tandem mass spectrometry method devoted to the quantitative determination of synephrine in bitter orange samples, containing a high quantity of synephrine, and sweet orange samples, known to contain a low level of synephrine but at the same time being one of the main synephrine sources in a normal human diet. Two bitter orange dry extracts containing 5 and 6% sSynephrine and 10 sweet orange samples have been analyzed. Between the sweet orange samples, six were fresh oranges and four were fresh-squeezed juices; in these samples, the synephrine levels ranged from 0.00128 to 0.00349%. 相似文献
67.
Aberrant spermatogenesis in the two species Stenognathellus denisi (Katiannidae) and Sminthurides aquaticus (Sminthurididae) is described. An ultrastructural study of spermatogenesis in these species has allowed us to reveal the presence of two types of secondary spermatocytes; one with a normal appearance, the other one is characterized by a small size, a reduced cytoplasm (showing only two centrioles), and a nucleus with very condensed chromatin. These latter aberrant cells are not able to perform the second meiotic division and will degenerate. This finding allows us to extend the identification of an aberrant spermatogenesis and the consequent post-zygotic sex determination to two more families of Symphypleona. 相似文献
68.
Summary
Vicia faba belongs to the sectionFaba. While the other species of the sectionV. narbonensis, V. johannis andV. bithynica cross enough well each other,V. faba seems to be strongly isolated from them. In addition the chromosome morphology ofV. faba differs from the other species of the section which among themselves are enough homogenous in this respect.To contribute to a wider knowledge on the taxonomical position ofV. faba in its section, electrophoretical and karyological analysis of 500 individuals belonging to 50 populations of different origin were carried out.The analyzed species were:V. faba, V. narbonensis, V. serratifolia, V. bithynica, V. galilaea andV. johannis.
Beitrag zur Taxonomie derVicia-Arten der SektionFaba
Zusammenfassung Vicia faba gehört zur sect.Faba. Während andere Arten der Sektion (V. narbonensis, V. johannis undV. bithynica) untereinander relativ gut kreuzbar sind, istV. faba von ihnen deutlich isoliert. Darüberhinaus unterscheidet sichV. faba in der Morphologie seiner Chromosomen von den anderen Arten der Sektion, die in dieser Hinsicht eine relativ einheitliche Merkmalsausprägung zeigen. Um zu einer besseren Kenntnis der systematischen Stellung vonV. faba innerhalb der Sektion beizutragen, wurden chromatographische und karyologische Analysen von 500 Individuen aus 50 Populationen verschiedener Herkunft durchgeführt. Analysiert wurdenV. faba, V. narbonensis, V. serratifolia, V. bithynica, V. galilaea undV. johannis.
Vicia, Faba
Vicia faba Faba. (V. narbonensis, V. johannis, V. bithynica) ,V. faba ë . ,V. faba , . V. faba , 500 50 . :V. faba, V. narbonensis, V. serratifolia, V. bithynica, V. galilaea, V. johannis.相似文献
69.
70.
Emiliana O. S. Batista Lais M. Vieira Bruno G. Freitas Bruna M. Guerreiro J. G. S. Carvalho Rodolfo D. Mingoti Guilherme Vasconcellos Alexandre H. Souza Jose Bento Sterman Ferraz Pietro Sampaio Baruselli 《Reproduction in domestic animals》2020,55(6):753-758
This study evaluated the association between plasma anti-Mullerian hormone (AMH) concentration and fertility in Nelore (Bos indicus) heifers submitted to timed artificial insemination (TAI). At the onset of the synchronization protocol, heifers (n = 289) received a subcutaneous P4 ear implant (3 mg) and 2 mg of oestradiol benzoate. Eight days later, the P4 implant was removed and 0.5 mg of oestradiol cypionate, prostaglandin (0.265 mg, i.m.) and equine chorionic gonadotropin (300 UI, i.m.) was administered, and TAI was performed 48 hr after ear implant removal. Ovarian ultrasound evaluations were performed to measure number of ovarian follicles, dominant follicle size and ovulation response. Pregnancy diagnosis was performed by ultrasound 30 days after AI. Heifers with greater circulating AMH had more antral follicles, a smaller dominant follicle near timed ovulation and lower ovulation response to the timed AI protocol compared to heifers with lower circulating AMH. Although AMH and pregnancy outcome had a quadratic-shaped pattern, AMH was not significantly associated with fertility. In conclusion, heifers with lower AMH had larger follicles towards the end of the synchronization protocol and greater ovulation responses, whereas greater circulating AMH was unrelated to conception success. 相似文献