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1.
Isolation, characterization and in vitro mitogenic stimulation of peripheral blood lymphocytes from an American buffalo. 下载免费PDF全文
A rapid and reproducible method is described for the isolation and characterization of leukocytes from the peripheral blood of an American buffalo (bison). Centrifugation of the buffy coat cells on a Percoll gradient (1.079 g/mL) at 650 x g for 20 min resulted in the separation and high yields of pure viable leukocytes. The sheep erythrocyte-rosetting technique (ER) showed that 59% of the cells were ER+ (T lymphocytes). Fluorescein isothiocyanate (FITC)-conjugated peanut agglutinin and FITC-conjugated concanavalin A revealed 77% and 89% positive cells, respectively. The isolated leukocytes contained adherent accessory cells and functionally active T and B lymphocytes which proliferated in response to both T and B cell mitogens and to exogenous recombinant bovine interleukin-2 in the absence and/or presence of the thiol compound 2-mercaptoethanol. 相似文献
2.
Physiological and morphological changes in bovine mammary glands following intramammary infusion of recombinant interferon-gamma. 总被引:1,自引:0,他引:1 下载免费PDF全文
Eleven lactating dairy cows were used to evaluate the response of bovine mammary glands to increasing doses of recombinant bovine interferon (rBoIFN)-gamma. Right front and rear quarters were intramammarily infused with eight different doses (10(2) U to 2 x 10(8) U/quarter) of rBoIFN-gamma; each dose was tested in at least two quarters. Left udder halves served as within animal controls in which quarters were injected with a saline placebo or were not infused at all. Milk secretion samples for compositional analysis were collected from each quarter prior to infusion and at 6, 24, 36 and 48 h following infusion. Animals were slaughtered immediately following the 48 h sampling period and mammary tissue was obtained for morphometric analyses. Milk composition was similar between control quarters and those quarters infused with up to 10(5) U of rBo-IFN-gamma during the entire sampling period. Quarters infused with 10(6) U and 10(7) U of rBoIFN-gamma had higher milk somatic cell counts (SCC) following treatment compared with preinfusion values. Changes in the composition of mammary secretion were most dramatic in quarters infused with greater than or equal to 10(8) U of rBoIFN-gamma as indicated by the significant increase in SCC and milk pH with a concomitant decrease in lactose concentration when compared with pre-infusion values or with control quarters. Morphometric analysis of tissue demonstrated an increase in stroma, a decrease in luminal area, and a marked increase in the number of infiltrating leukocytes in those quarters infused with the higher doses of rBoIFN-gamma.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
3.
N. LA PORTA P. CAPRETTI K. KAMMIOVIRTA R. KARJALAINEN & K. KORHONEN 《Plant pathology》1997,46(5):773-784
Eighty-six Heterobasidion annosum isolates, mainly belonging to the F intersterility group and obtained from 32 different geographical localities in Italy, were subjected to genetic analysis by the Random Amplified Polymorphic DNA (RAPD) markers. The similarity between F and S groups was higher than that between F and P. In UPGMA Cluster Analysis, the F isolates originating from the same locality usually grouped in the same cluster. The isolates also showed a tendency to group at the level of larger geographical areas. Within the F group, isolates from the south of the Italian peninsula showed the highest genetic variation and northern isolates from the Alpine regions showed the lowest. This indicates a gradual cline along the peninsula. The genetic variability in the Italian F group is discussed in relation to the past and present distribution of the host species in Italy and Europe. 相似文献
4.
Laryngeal mask airway and transient hypercapnic hyperpnea for video‐endoscopic assessment of unilateral laryngeal paralysis in dogs 下载免费PDF全文
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Mutwiri G Pontarollo R Babiuk S Griebel P van Drunen Littel-van den Hurk S Mena A Tsang C Alcon V Nichani A Ioannou X Gomis S Townsend H Hecker R Potter A Babiuk LA 《Veterinary immunology and immunopathology》2003,91(2):89-103
Bacterial DNA contains a much higher frequency of CpG dinucleotides than are present in mammalian DNA. Furthermore, bacterial CpG dinucleotides are often not methylated. It is thought that these two features in combination with specific flanking bases constitute a CpG motif that is recognized as a "danger" signal by the innate immune system of mammals and therefore an immune response is induced when these motifs are encountered. These immunostimulatory activities of bacterial CpG DNA can also be achieved with synthetic CpG oligodeoxynucleotides (ODN). Recognition of CpG motifs by the innate immune system requires engagement of Toll-like receptor 9 (TLR-9), which induces cell signaling and subsequently triggers a pro-inflammatory cytokine response and a predominantly Th1-type immune response. CpG ODN-induced innate and adaptive immune responses can result in protection in various mouse models of disease. Based on these observations, clinical trials are currently underway in humans to evaluate CpG ODN therapies for cancer, allergy and infectious disease. However, potential applications for immunostimulatory CpG ODN in species of veterinary importance are just being explored. In this review, we will highlight what is presently known about the immunostimulatory effects of CpG ODN in domestic animals. 相似文献
7.
Babiuk LA 《Veterinary journal (London, England : 1997)》2002,164(3):188-201
Conventional vaccines have been used for some 200 years, primarily to control infectious diseases. It is envisaged that such vaccines will continue to be used and new ones developed using conventional technology. However, in addition to conventional vaccines, novel approaches using biotechnology are already in use and many more are in various stages of development. These novel vaccines are not only being used to control infectious diseases, but also to improve productivity of livestock by modulating hormones, for gender selection, as well as in controlling ectoparasites. The recent developments in vaccination technology in all of these areas are described. 相似文献
8.
Nucleic acid vaccines: research tool or commercial reality 总被引:3,自引:0,他引:3
Babiuk LA Babiuk SL Loehr BI van Drunnen Littel-van den Hur 《Veterinary immunology and immunopathology》2000,76(1-2):1-23
Polynucleotide immunization has captured the imagination of numerous researchers and commercial companies around the world as a novel approach for inducing immunity in animals. Clearly, the 'proof-of-principle' has been demonstrated both in rodents and various animal species. However, to date, no commercial veterinary vaccine has been developed, or to our knowledge, is in the licensing phase. The present review summarizes the types of pathogens and host species for which polynucleotide immunization has been tried. We have tried to identify possible barriers to commercialization of this technology and areas that need attention if this promising technology is ever to become a reality in the commercial arena. 相似文献
9.
Reddy PS Idamakanti N Pyne C Zakhartchouk AN Godson DL Papp Z Baca-Estrada ME Babiuk LA Mutwiri GK Tikoo SK 《Veterinary immunology and immunopathology》2000,76(3-4):257-268
Replication-competent and replication-defective bovine adenovirus type 3 recombinants expressing the bovine herpesvirus type 1 (BHV-1) glycoprotein D (gD) were tested for induction of gD specific immune responses in calves using intratracheal (1st and 2nd immunization) and sub-cutaneous (3rd immunization) route of immunization. The replication-defective recombinant BAV501 induced systemic immune responses against gD as low titers of anti gD-IgG were detected in the serum. However, the efficacy of the replication-competent BAV3.E3gD to induce gD-specific antibodies in the serum and the nasal secretions was superior to that of replication-defective BAV501 when both viruses were given at the same dosage. Partial protection from challenge was induced in calves immunized with replication-competent BAV3.E3gD. A dramatic increase in the titers of anti-gD IgG and IgA levels, both in serum and nasal secretions, following BHV-1 challenge (anamnestic response) suggested that the animals immunized with replication-defective BAV501 had been primed for gD-specific antibody responses. 相似文献
10.