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81.
Echinococcosis is very frequent helminthic infection in human being. The disease is endemic in Iran and particularly in its northwestern region, East Azerbaijan. The objective of this study was to study demographics of patients with cystic echinococcosis in East Azerbaijan; as well as to repot the sites of involvements. In this cross-sectional study, 318 patients with surgical and nonsurgical cystic echinococcosis were recruited from three referral centers in Tabriz within a 10-year period of time. The patients' demographics (age and gender) and the site of infection were investigated. Among the patients, females were predominant (57.5 vs. 42.5%). The mean age of patients was 32.59 +/- 18.47 (range: < 1-87) years and the most frequently age group was 20-30 years (23.6%), followed by the age groups of 30-40 years (21.7%), 10-20 years (14.2%), 40-50 years (11.9%), 50-60 years (11.3%), < 1 year (6%), 60-70 years (4.7%), 1-10 years (4.1%) and finally, > 70 years (2.5%). The lung was the most frequently infected organ (48.1%), followed by the liver (28.9%), gallbladder (3.5%), spleen and kidney (each one in 2.2%), abdomen, intestine, pleura, bronchus and mediastinum (each one in 1.6%), chest wall and heart (each one in 1.3%), brain, pericardium, facial sinus, pancreas and esophagus (each one in 0.6%) and the ovary, uterus, axillary region, pelvis and femur (each one in 0.3%). In conclusion, this study showed that the patients with hydatid cysts in East Azerbaijan Province are mainly females in the age group of 20-40 years. The lung and liver are the major sites of infection in these patients.  相似文献   
82.
Plasmid transfer among isolates of Rhizobium leguminosarum bv. viciae in heavy metal contaminated soils from a long-term experiment in Braunschweig, Germany, was investigated under laboratory conditions. Three replicate samples each of four sterilized soils with total Zn contents of 54, 104, 208 and 340 mg kg−1 were inoculated with an equal number (1×105 cells g−1 soil) of seven different, well-characterized isolates of R. leguminosarum bv. viciae. Four of the isolates were from an uncontaminated control plot (total Zn 54 mg kg−1) and three were from a metal-contaminated plot (total Zn 340 mg kg−1).After 1 year the population size was between 106 and 107 g−1 soil, and remained at this level in all but the most contaminated soil. In the soil from the most contaminated plot no initial increase in rhizobial numbers was seen, and the population declined after 1 year to <30 cells g−1 soil after 4 years. One isolate originally from uncontaminated soil that had five large plasmids (no. 2-8-27) was the most abundant type re-isolated from all of the soils. Isolates originally from the metal-contaminated soils were only recovered in the most contaminated soil. After 1 year, four isolates with plasmid profiles distinct from those inoculated into the soils were recovered. One isolate in the control soil appeared to have lost a plasmid. Three isolates from heavy metal contaminated soils (one isolate from the soil with total Zn 208 mg kg−1 and two isolates from the soil with total Zn 340 mg kg−1) had all acquired one plasmid. Plasmid transfer was confirmed using the distinct ITS-RFLP types of the isolates and DNA hybridization using probes specific to the transferred plasmid. The transconjugant of 2-8-27 which had gained a plasmid was found in one replicate after 2 years of the most contaminated soil but comprised more than 50% of the isolates. A similar type appeared in a separate replicate of the most contaminated soil after 3 years and persisted in both of these soils until the final sampling after 4 years. After 2 years isolates were recovered from four of the soil replicates with the chromosomal type of 2-8-27 which appeared to have lost one plasmid, but these were not recovered subsequently.Isolate 2-8-27 was among the isolates most sensitive to Zn in laboratory assays, whereas isolate 7-13-1 showed greater zinc tolerance. Acquisition of the plasmid conferred enhanced Zn tolerance to the recipients, but transconjugant isolates were not as metal tolerant as 7-13-1, the putative donor. Laboratory matings between 2-8-27 and 7-13-1 in the presence of Zn resulted in the conjugal transfer of the same small plasmid from 7-13-1 to isolate 2-8-27 and the transconjugant had enhanced metal tolerance. Our results show that transfer of naturally-occurring plasmids among rhizobial strains is stimulated by increased metal concentrations in soil. We further demonstrate that the transfer of naturally-occurring plasmids is important in conferring enhanced tolerance to elevated zinc concentrations in rhizobia.  相似文献   
83.
Summary Water application pattern, WAP, is one of the most important factors that determine the instantaneous and the cumulative application rates of moving irrigation machines. The mathematical background of a procedure to predict and design the WAP of moving irrigation machines is introduced. It includes a mathematical analysis of the effect of pressure head, height and spacing between emitters on the WAP, and a nomograph that presents this analysis graphically and illustrates the design procedure of the application pattern of irrigation machines.Abbreviations P()a water application rate at a normalized radial distance from the emitter [m/s] - ka number of linear segments needed to represent the pattern - s/Ra normalized radial distance from the emitter - Ra wetted radius [m] - sa radial distance from the emitter [m] - n j n i/ha normalized water application rate at point - j, ha maximum water application rate [m/s] n j water application rate at point j [m/s] - j =m j/Ra normalized radial distance of point j from emitter - m ja radial distance of point - ja from emitter [m], CWAP - (x)a Cumulative Water Application Pattern: amount of water per unit area applied at a distance - xa from the travel path of the emitter [m3/m2] - xa distance from the travel path of the emitter [m] - T xa time of application at a distance - xa from the travel path of the emitter [s] - va velocity of propagation of the machine [m/s] - k 1a the outmost linear segment that its radial distance from the emitter - m k1a is smaller than the distance of the travel path from the emitter - x, T ja time at which the - j tha linear segment (ring) stops influencing the point located at a distance - xa from the emitter - 1, 2, 3a dimensionless numbers derived by dimensional analysis - ua water jet velocity [m/s] - ga gravity acceleration [m/s2] - da nozzle diameter [m], v kinematic viscosity [m2/s] - Ha emitters height [m] - , a regression analysis coefficients - Paa Pattern fit coefficient for water application - F(r)a normalized desired water application pattern [1/m] - f(r)a normalized actual water application pattern [1/m] - La common distance on which - F(r) and f(r)a are defined [m], SP spacing interval between emitters [m] - DSa dimensionless spacing interval between emitters - DSa variation of dimensionless spacing interval - Paa variation of Pa coefficient - Pa pressure head [kPa]  相似文献   
84.
Kisra is a naturally lactic acid bacteria‐ and yeast‐fermented sorghum thin pancake‐like flatbread produced in Sudan. Kisra has considerable potential as the basis for development of a gluten‐free sandwich wrap. To help direct cultivar selection for commercial production of these products, two white, tan plant non‐tannin Type I, one white Type II tannin, and one red Type III tannin sorghum cultivars were evaluated with respect to kisra protein quality and physical characteristics. Kisra from the non‐tannin sorghums were flexible and had an open‐textured structure with many regular gas cells, whereas those from the tannin sorghums were more brittle, denser in structure, and contained far fewer and smaller gas cells. Kisra from the tannin sorghums had the lowest reactive lysine content, in vitro protein digestibility, and Protein Digestibility Corrected Amino Score (PDCAAS), with values being lowest for the Type III sorghum. PDCAAS of kisra from the Type III sorghum was only 0.12, less than half of that from the Type I sorghums. As the tannins in tannin sorghums adversely affect kisra protein quality and physical characteristics, white tan plant, non‐tannin sorghum cultivars are most suitable for kisra production and for development of wrap‐type sorghum‐based baked goods.  相似文献   
85.
Feline spongiform encephalopathy (FSE) is thought to have resulted from consumption of food contaminated with bovine spongiform encephalopathy and the latter is believed to result from the consumption of food contaminated with scrapie. However, no direct experimental documentation exists to indicate that the scrapie agent is capable of amplifying in cats, and, therefore, crossing the species barrier. During 1979, 6 cats ranging in age from 3.5 to 18 months were intracerebrally inoculated with sheep scrapie (inoculum G-639-PP) and were observed for an extended period. Inoculated cats did not develop neurologic disease, and microscopic lesions of spongiform encephalopathy were not evident. Immunohistochemistry and Western blot techniques failed to detect the abnormal form of prion protein (PrP(res)). These results indicate that the sheep scrapie agent (G-639-PP) used in this study was not capable of amplifying in cats and therefore was unable to cross the species barrier to produce FSE.  相似文献   
86.
The expression of constitutive endothelial nitric oxide synthase (eNOS) and inducible NOS (iNOS) in the brains of cattle with natural rabies was studied. Increased expression of eNOS was detected in neurons of the brain stem and Purkinje cells of cerebellum. By contrast, iNOS was diffusely localized in the cytoplasm of affected neurons, and some inflammatory cells were positive. eNOS and rabies antigen were co-localized in inclusion bodies (Negri bodies) in neurons. The specific localization of eNOS, but not iNOS, in the Negri bodies suggests that eNOS is involved in the formation of rabies virus inclusion bodies.  相似文献   
87.
The 16S r RNA gene of 49 streptococci of serological group B isolated from various origins was amplified by polymerase chain reaction (PCR) and subsequently digested with the restriction enzymes Rsa I and Msp I. The restriction profiles of all group B streptococci appeared to be identical indicating no intraspecies sequence variations of this gene. A fragment of the gene of two group B-streptococcal reference strains, including the hypervariable V2 region, could be amplified by PCR and sequenced. The sequence appeared to be identical and allowed the design of species-specific oligonucleotide primers. The primer pair used produced an amplicon with a size of 1250 bp and correctly identified all 49 group B-streptococci investigated but none of the control strains of various species and serogroups. This primer could be used in a multiplex PCR and allowed a rapid identification of bacteria of this species.  相似文献   
88.
BACKGROUND: Knowing that adenoviral vectors could initiate innate immunity, the ability of E1-deleted recombinant adenovirus (Ad-E1Delta) in induction of B7.1 and IL-2 molecules was studied. METHODS: The expression of green fluorescent protein in C1498 cells following transfection of these cells with adenovirus green fluorescent protein vector confirmed the ability of adenovirus vectors in infecting the cells and inducing the expression of the gene of interest. The expression of B7.1 molecule on the surface of the cells was assayed upon infection with Ad-E1Delta vector. Adenovirus-IL-2/B7.1 vector capable of inducing IL-2 and B7.1 expression in the cells was used as the positive control vector. RESULTS: According to the FACS results, about 4.17% of normal cells expressed B7.1 on their surface, while this level was increased in Ad-E1Delta transduced cells up to 14.43%. These results demonstrate that Ad-E1Delta vector considerably (about 3 folds) increases the expression of B7.1 on the cells. No detectable IL-2 was secreted into the medium of non-transduced and Ad-E1Delta transduced cells. CONCLUSION: Data indicate that the infection of C1498 cells with recombinant adenoviruses stimulates expression of B7.1 on the cell surface rather than secretion of IL-2 into the medium.  相似文献   
89.
The thermal treatment method was employed to achieve higher homogeneity of calcium ferrite (CaFe2O4) and Poly (vinyl alcohol) (PVA) nanocomposites. The influences of phase transformation on physical and biological properties of calcined specimens were investigated by various experimental techniques including X-ray diffraction (XRD), Transmission Electron Microscopy (TEM), high resolution Field emission scanning electron microscope (FESEM) and Fourier transform infrared spectroscopy (FT-IR). Heat treatment was conducted at temperatures between 723 and 923 K, so that a phase transformation occurred from cubic to orthorhombic spinel structure at 923 K. The chemical analysis of the PVA/CaFe2O4 nanocomposite was performed by energy dispersion X-ray analysis (EDXA), demonstrated the PVA/CaFe2O4 nanocomposites contained the elements of C, Ca, Fe, and O. The formed nanocomposites exhibited ferromagnetic behaviors which were confirmed by using a vibrating sample magnetometer (VSM). The calcined specimens were carried out to an antimicrobial or antifungal test.  相似文献   
90.
MicroRNAs (miRNAs) are important regulators of gene expression and are known to play a key role in regulating both adaptive and innate immunity. Bovine alveolar macrophages (BAMs) help maintain lung homeostasis and constitute the front line of host defense against several infectious respiratory diseases, such as bovine tuberculosis. Little is known, however, about the role miRNAs play in these cells. In this study, we used a high-throughput sequencing approach, RNA-seq, to determine the expression levels of known and novel miRNAs in unchallenged BAMs isolated from lung lavages of eight different healthy Holstein–Friesian male calves. Approximately 80 million sequence reads were generated from eight BAM miRNA Illumina sequencing libraries, and 80 miRNAs were identified as being expressed in BAMs at a threshold of at least 100 reads per million (RPM). The expression levels of miRNAs varied over a large dynamic range, with a few miRNAs expressed at very high levels (up to 800,000 RPM), and the majority lowly expressed. Notably, many of the most highly expressed miRNAs in BAMs have known roles in regulating immunity in other species (e.g. bta-let-7i, bta-miR-21, bta-miR-27, bta-miR-99b, bta-miR-146, bta-miR-147, bta-miR-155 and bta-miR-223). The most highly expressed miRNA in BAMs was miR-21, which has been shown to regulate the expression of antimicrobial peptides in Mycobacterium leprae-infected human monocytes. Furthermore, the predicted target genes of BAM-expressed miRNAs were found to be statistically enriched for roles in innate immunity. In addition to profiling the expression of known miRNAs, the RNA-seq data was also analysed to identify potentially novel bovine miRNAs. One putatively novel bovine miRNA was identified. To the best of our knowledge, this is the first RNA-seq study to profile miRNA expression in BAMs and provides an important reference dataset for investigating the regulatory roles miRNAs play in this important immune cell type.  相似文献   
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