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111.
Transforming fusions of FGFR and TACC genes in human glioblastoma   总被引:1,自引:0,他引:1  
The brain tumor glioblastoma multiforme (GBM) is among the most lethal forms of human cancer. Here, we report that a small subset of GBMs (3.1%; 3 of 97 tumors examined) harbors oncogenic chromosomal translocations that fuse in-frame the tyrosine kinase coding domains of fibroblast growth factor receptor (FGFR) genes (FGFR1 or FGFR3) to the transforming acidic coiled-coil (TACC) coding domains of TACC1 or TACC3, respectively. The FGFR-TACC fusion protein displays oncogenic activity when introduced into astrocytes or stereotactically transduced in the mouse brain. The fusion protein, which localizes to mitotic spindle poles, has constitutive kinase activity and induces mitotic and chromosomal segregation defects and triggers aneuploidy. Inhibition of FGFR kinase corrects the aneuploidy, and oral administration of an FGFR inhibitor prolongs survival of mice harboring intracranial FGFR3-TACC3-initiated glioma. FGFR-TACC fusions could potentially identify a subset of GBM patients who would benefit from targeted FGFR kinase inhibition.  相似文献   
112.
A new species of the genus Henneguya (Henneguya multiplasmodialis n. sp.) was found infecting the gills of three of 89 specimens (3.3%) of Pseudoplatystoma corruscans and two of 79 specimens (2.6%) of Pseudoplatystoma reticulatum from rivers in the Pantanal wetland, Brazil. Partial sequencing of the 18S rDNA gene of the spores obtained from one plasmodium from the gills of P. corruscans and other one from the gills of P. reticulatum, respectively, resulted in a total of 1560 and 1147 base pairs. As the spores of H. multiplasmodialis n. sp. resemble those of Henneguya corruscans, which is also a parasite of P. corruscans, sequencing of the 18S rDNA gene of the spores of H. corruscans found on P. corruscans caught in the Brazilian Pantanal wetland was also provided to avoid any taxonomic pendency between these two species, resulting in 1913 base pairs. The sequences of H. multiplasmodialis n. sp. parasite of P. corruscans and P. reticulatum and H. corruscans did not match any of the Myxozoa available in the GenBank. The similarity of H. multiplasmodialis n. sp. obtained from P. corruscans to that from P. reticulatum was of 99.7%. Phylogeny revealed a strong tendency among Henneguya species to form clades based on the order and/or family of the host fish. H. multiplasmodialis n. sp. clustered in a clade with Henneguya eirasi and H. corruscans, which are also parasites of siluriforms of the family Pimelodidae and, together with the clade composed of Henneguya spp. parasites of siluriforms of the family Ictaluridae, formed a monophyletic clade of parasites of siluriform hosts. The histological study revealed that the wall of the plasmodia of H. multiplasmodialis n. sp. were covered with a stratified epithelium rich in club cells and supported by a layer of connective tissue. The interior of the plasmodia had a network of septa that divided the plasmodia into numerous compartments. The septa were composed of connective tissue also covered on both sides with a stratified epithelium rich in club cells. Inflammatory infiltrate was found in the tissue surrounding the plasmodia as well as in the septa.  相似文献   
113.

Background

Analysis of data collected from pig farms may be useful to understand factors affecting pig health and productive performance. However, obtaining these data and drawing conclusions from them can be done at different levels and presents several challenges. In the present study, information from 688 batches of growing-finishing (GF) pigs (average initial and final body weight of 19.1 and 108.5 kg respectively) from 404 GF farms integrated in 7 companies was obtained between July 2008 and July 2010 in Spain by survey. Management and facility factors associated with feed conversion ratio (FCR) and mortality were studied by multiple linear regression analysis in each single company (A to G) and in an overall database (OD). Factors studied were geographic location of the farm, trimester the pigs entered the farm, breed of sire and sex segregation in pens (BREGENSEG), use of circovirus vaccine, number of origins the pigs were obtained from, age of the farm, percentage of slatted floor, type of feeder, drinker and ventilation, number of phases and form of feed, antibiotic administration system, water source, and number and initial weight of pigs.

Results

In two or more companies studied and/or in OD, the trimester when pigs were placed in the farm, BREGENSEG, number of origins of the pigs, age of the farm and initial body weight were factors associated with FCR. Regarding mortality, trimester of placement, number of origins of the pigs, water source in the farm, number of pigs placed and the initial body weight were relevant factors. Age of the farm, antibiotic administration system, and water source were only provided by some of the studied companies and were not included in the OD model, however, when analyzed in particular companies these three variables had an important effect and may be variables of interest in companies that do not record them.

Conclusions

Analysing data collected from farms at different levels helps better understand factors associated with productive performance of pig herds. Out of the studied factors trimester of placement and number of origins of the pigs were the most relevant factors associated with FCR and mortality.  相似文献   
114.
115.
Comparison of black,purple, and yellow barleys   总被引:1,自引:0,他引:1  
Many barley landraces are purple-or black-seeded, but the chemical composition of these purple-and black- seeded barley is rarely examined. Therefore, studies were conducted to determine if the chemical composition of purple and black barleys differs from that of yellow barleys. Four sets of genetic materials were used for these studies: 96 doubled-haploid (DH) lines, 10 near-isogenic lines, 40 landraces, and four F3 bulks. The results showed that purple DH lines contained a similar amount of lignin as yellow DH lines and that anthocyanin-containing isogenic lines did not differ from anthocyanin-free lines in lignin content. Therefore, these results suggest that anthocyanin biosynthesis is independent of lignin biosynthesis in barley. The results also showed that black barley contained more protein and more lignin than yellow barley in two crosses and that among the 40 landraces studied, the three with the highest concentration of lignin happened to be black seeded. Lignin content was not associated with seed weight except in defective endosperm lines. The presence of pigments and a relatively high concentration of lignin might help reduce the level of kernel blight severity in black barley. More studies are needed to determine the chemical composition and pest resistance associated with purple and black barleys.  相似文献   
116.
The presence and the distribution of neuroendocrine cells in the gastrointestinal tract of adult wild boar were investigated. The endocrine cells have been identified by means of immunocytochemical techniques using antibodies against serotonin, gastrin, somatostatin, cholecystokinin (CCK), met-enkephalin (MET-ENK), gastric-inhibitory peptide (GIP) and glucagon. The number of positive cells for each antiserum in each region was evaluated. Results were compared with data present in the literature and obtained previously by us and other authors in swine and domestic mammals (Ceccarelli et al., 1985, 1987, 1990, 1991, 1995; Capella and Solcia, 1972; Domeneghini and Castaldo, 1981; Peranzi and Lehy, 1984; Krause et al., 1985).  相似文献   
117.
The proximal and interlobular ducts of rabbit zygomatic glands show a particular morphological feature consisting of numerous secretory granules localized in the apical cytoplasm of the cells. It is suggested that there is a similarity between these ducts and the granular ducts of submandibular glands in rodents.  相似文献   
118.
Heterosis and mixing effects in barley under drought stress   总被引:1,自引:0,他引:1  
Yield stability is one of the main breeding objectives in breeding for stress environments, such as the semi‐arid areas of Syria. The objectives of this study were to measure the effects of heterogeneity and heterozygosity on yield and yield stability by comparing doubled haploid lines (DHL) in mixed vs. pure stand (influence of heterogeneity) and F2 populations vs. corresponding DHL mixtures (influence of heterozygosity). Six barley lines from two gene pools (LR = landraces, EL = experimental lines) were used to produce nine crosses (two LR × LR, three EL × EL, four LR × EL). The F2 generation and eight DHL per cross were produced from each cross. The six parental DHL, nine F2 populations, nine 8‐line mixtures and 72 DHL in pure stands were tested in five environments under drought stress in north Syria. The mean superiority of F2 populations over DHL mixtures for yield traits across environments and cross combinations ranged between 7.5 and 10%. The effect of heterogeneity was small throughout. For grain yield, harvest index, 1000‐grain weight and plant height significant interactions between heterozygosity levels and environments were observed. The effect of heterozygosity for grain yield increased substantially from ‐1.2% in the highest‐yielding environment to 45.6% in the most stressful environment. Interactions between levels of heterozygosity and cross combinations were significant for most traits. F2 populations were considerably more stable than DHL in pure stands, yet not as stable as DHL mixtures. It is concluded that heterozygosity is more important than heterogeneity in breeding for improved yield and yield stability under drought stress.  相似文献   
119.
Diversity for Disease Resistance in Barley Landraces from Syria and Jordan   总被引:1,自引:0,他引:1  
A number of barley landraces collected in Syria and Jordan were evaluated for resistance to yellow rust, powdery mildew, scald and covered smut by inoculating single-head progenies with local pathogen strains during two years of field tests. A large diversity in resistance was observed for each pathogen both between populations of different collection sites as well as between head progenies within collection sites. The level of resistance varied from absolute and partial resistant types up to highly susceptible lines. No consistent association between the environmental conditions of the collection site and the level of resistance of the landrace-lines could be found.  相似文献   
120.
Selection of Barley Lines for Drought Tolerance in Low-Rainfall Areas   总被引:1,自引:0,他引:1  
An experiment was conducted at five locations in Jordan (Khanasri, annual rainfall 150 mm; Ramtha, 225 mm; Muwaqar, 150 mm; Rabba, 350 mm; Ghweer, 250 mm) during the 1996/1997 growing season, to evaluate the yield performance and some agronomic traits of 84 barley breeding lines and three long‐term checks (Zanbaka, Arta and Klaxon) for drought tolerance. An α‐lattice design with two replications and six incomplete blocks for each replication was used. Genotype 6 (WI2291/Tadmor) was found to be superior in grain yield, especially compared to the best check (Arta) at the two wettest locations (Rabba and Ghweer). Genotype 21 (Mo.B1337/WI2291/5/Emir/Sb//CM67/3/F8‐HB‐854‐23/121//148‐221/4/CI 08887/CI05761) out‐yielded the best check (Arta) at the driest location (Khanasri), while genotype 61 (Salmas/Arabia Aswad) produced a higher grain yield than the best check (Zanbaka) at Ramtha. The correlations amongst grain yield, biological yield, straw yield, plant height and harvest index were always significant and positive regardless of the location. The correlations amongst days to heading, days to maturity and grain yield were significant at the two driest locations only. This suggests that different phonologies are required to maximize grain yield in wet and dry environments. Also, the relationship between grain yield and the length of grain‐filling period was positive in the wettest location (Rabba), negative in the driest (Khanasri) and not significant at the two intermediate locations. These results emphasize the importance of selection in the target environment and the need to develop early‐maturing genotypes as a way of withstanding drought and high temperatures during the grain‐filling period. A high and negative correlation coefficient was found between the drought susceptibility index and grain yield at the driest site, whereas at the wettest site the correlation coefficient was lower and in some cases positive, indicating the existence of traits that are desirable under drought and undesirable under favourable conditions.  相似文献   
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