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731.
The phylogenic significance of the subdivision of dual olfactory system is reviewed mainly on the basis of our findings by electron microscopy and lectin histochemistry in the three amphibian species. The dual olfactory system is present in common in these species and consists of the projection from the olfactory epithelium (OE) to the main olfactory bulb (MOB) and that from the vomeronasal epithelium (VNE) to the accessory olfactory bulb (AOB). The phylogenic significance of subdivisions in the dual olfactory system in the amphibian must differently be interpreted. The subdivision of the MOB into its dorsal region (D-MOB) and ventral region (V-MOB) in Xenopus laevis must be attributed to the primitive features in their olfactory receptors. The middle cavity epithelium lining the middle cavity of this frog possesses both ciliated sensory cells and microvillous sensory cells, reminding the OE in fish. The subdivision of the AOB into the rostral (R-AOB) and caudal part (C-AOB) in Bufo japonicus formosus must be regarded as an advanced characteristic. The lack of subdivisions in both MOB and AOB in Cynops pyrrhogaster may reflect their phylogenic primitiveness. Since our lectin histochemistry to detect glycoconjugates expressed in the olfactory pathway reveals the subdivisions in the dual olfactory system in the amphibian, the glycoconjugates may deeply participate in the organization and function of olfactory pathways in phylogeny.  相似文献   
732.
A genome-wide scan for QTL affecting economically important traits in beef production was performed using an F(2) resource family from a Japanese Black x Limousin cross, where 186 F(2) animals were measured for growth, carcass, and meat-quality traits. All family members were genotyped for 313 informative microsatellite markers that spanned 2,382 cM of bovine autosomes. The centromeric region of BTA2 contained significant QTL (i.e., exceeding the genome-wide 5% threshold) for 5 carcass grading traits [LM area, beef marbling standards (BMS) number, luster, quality grade, and firmness), 8 computer image analysis (CIA) traits [LM lean area, ratio of fat area (RFA) to LM area, LM area, RFA to musculus (M.) trapezius area, M. trapezius lean area, M. semispinalis lean area, RFA to M. semispinalis area, and RFA to M. semispinalis capitis area], and 5 meat quality traits (contents of CP, crude fat, moisture, C16:1, and C18:2 of LM). A significant QTL for withers height was detected at 80.3 cM on BTA5. We detected significant QTL for the C14:0 content in backfat and C14:0 and C14:1 content in intermuscular fat around the 62.3 to 71.0 cM region on BTA19 and for C14:0, C14:1, C18:1, and C16:0 content and ratio of total unsaturated fatty acid content to total SFA content in intramuscular fat at 2 different regions on BTA19 (41.1 cM for C14:1 and 62.3 cM for the other 4 traits). Overall, we identified 9 significant QTL regions controlling 27 traits with genome-wide significance of 5%; of these, 22 traits exceeded the 1% genome-wide threshold. Some of the QTL affecting meat quality traits detected in this study might be the same QTL as previously reported. The QTL we identified need to be validated in commercial Japanese Black cattle populations.  相似文献   
733.
The purposes of the present study were to elucidate the pharmacokinetics of zonisamide, determine the presence of a drug interaction with phenobarbital, and evaluate how long any interaction lasted after discontinuation of phenobarbital in dogs. Five dogs received zonisamide (5 mg/kg, p.o. and i.v.) before and during repeated oral administration of phenobarbital (5 mg/kg, bid, for 30–35 days). Zonisamide (5 mg/kg, p.o.) was also administered 8, 10, and 12 weeks after discontinuation of phenobarbital. Blood was sampled until 24 h after each zonisamide administration and serum concentrations of zonisamide were determined. Repeated phenobarbital decreased the maximum serum concentration, area under the serum concentration vs. time curve, apparent elimination half-life, and bioavailability of zonisamide. Total clearance increased. Time to maximum serum concentration and volume distribution were not changed. The maximum serum concentration and area under the serum concentration vs. time curve of zonisamide continued to be low until 10 weeks after the discontinuation of phenobarbital. They were restored to the same serum concentration as before phenobarbital administration 12 weeks after the discontinuation of phenobarbital. These data suggested that repeated administration of a clinical dose of phenobarbital enhanced the clearance of zonisamide and the enhanced clearance lasted at least 10 weeks after the discontinuation of phenobarbital. Caution may be necessary when zonisamide is given with phenobarbital and when antiepileptic therapy is changed from phenobarbital to zonisamide.  相似文献   
734.
For proper management and conservation of the Kuril harbor seal (Phoca vitulina stejnegeri) through disease control, serological analysis was performed for influenza A virus infection in free-ranging seals in Hokkaido, Japan. Serum samples were collected from seals at Nosappu (231 seals), Akkeshi (16) and Erimo (75), between 1998 and 2005, and were analyzed by ELISA. Antibodies to the influenza A virus were detected only in seals from Nosappu. The incidences were 11% (1/9), 3% (2/66), 12% (7/59) and 6% (5/77) in 1998, 2003, 2004 and 2005, respectively. These suggest sporadic infection. Because antibody-positive seals included juvenile seals in each year, the infections were considered to have been circulated since no later than the late 1990s until recent years. ELISA-positive sera were analyzed by hemagglutination inhibition (HI) tests to determine the subtypes. Antibodies to the H3 and H6 subtypes were detected in 10 and 2 sera, respectively. Two of the sera that had antibodies to the H6 subtype also had antibodies to the H3 subtype. These two seals were considered to have been infected with both the H3 and H6 subtypes. This is the first investigation to find antibodies to the H6 subtype in seals. Although the H6 subtype had been isolated only from avians, genetic analysis had suggested that the H6 subtype could become a novel mammalian pathogen. For definitive diagnosis, detection of the virus from the tissue or mucus of seals is required.  相似文献   
735.
BACKGROUND: Cerebrospinal fluid (CSF) analysis is the basis for establishing a diagnosis of central nervous system (CNS) inflammation. However, the information provided by routine CSF analysis is limited. Determination of CSF beta-2-microglobulin (beta2m) concentration has been used diagnostically in humans to identify inflammatory CNS disease; we hypothesized that it may have similar value in dogs. OBJECTIVES: The objective of this study was to measure (beta2m concentration in the CSF of clinically healthy dogs and compare the values to those observed in dogs with inflammatory CNS disease and intervertebral disc disease (IVDD). METHODS: CSF was collected from 10 clinically healthy laboratory dogs and 11 dogs each with inflammatory CNS disease and IVDD. Routine CSF analysis was performed, and (beta2m concentration was measured by ELISA. CSF (beta2m concentration and CSF:serum (beta2m ratio were compared between groups by ANOVA. Linear relationships between CSF total nucleated cell count (TNCC), RBC count, total protein concentration, and (beta2m concentration were assessed by regression analysis. RESULTS: The mean (+/- SD) CSF (beta2m concentration in clinically healthy dogs was 0.36 (+/- 0.05 microg/mL (cisternal) and 0.40 (+/- 0.07 microg/mL (lumbar). Median CSF (beta2m concentration in dogs with IVDD (0.46 microg/mL) and inflammatory CNS disease (0.85 microg/mL) differed from that of controls (0.36 microg/mL; P=.002). The concentration also differed between the 2 disease groups (P=.01). Five dogs with inflammatory CNS disease had CSF:serum (beta2m ratios >1. A correlation was identified between TNCC and (beta2m concentration (r=0.69, P=.0003). CONCLUSIONS: CSF (beta2m concentration is higher in dogs with IVDD and inflammatory CNS disease, with highest values seen with inflammatory disease. This may be attributed in part to the correlation between CSF (beta2m concentration and TNCC, but also may reflect intrathecal immune activation.  相似文献   
736.
Pigs and humans have shared influenza A viruses (IAV) since at least 1918, and many interspecies transmission events have been documented since that time. However, despite this interplay, relatively little is known regarding IAV circulating in swine around the world compared with the avian and human knowledge base. This gap in knowledge impedes our understanding of how viruses adapted to swine or man impacts the ecology and evolution of IAV as a whole and the true impact of swine IAV on human health. The pandemic H1N1 that emerged in 2009 underscored the need for greater surveillance and sharing of data on IAV in swine. In this paper, we review the current state of IAV in swine around the world, highlight the collaboration between international organizations and a network of laboratories engaged in human and animal IAV surveillance and research, and emphasize the need to increase information in high‐priority regions. The need for global integration and rapid sharing of data and resources to fight IAV in swine and other animal species is apparent, but this effort requires grassroots support from governments, practicing veterinarians and the swine industry and, ultimately, requires significant increases in funding and infrastructure.  相似文献   
737.
This study investigated an objective method for estimating beef marbling using ultrasonic images of the Iliocostalis muscle and the Lomgissimus muscle area sections. Thirty‐one Japanese Black cattle steers were used in this study. The end of the left side shoulder blade bone was scanned using an ultrasonic device. Ultrasonic images were captured of the Longissimus muscle area and that around the Iliocostalis muscle area. Twenty items were measured in the two images using computer image analysis software. The level of beef marbling was measured according to the Beef Marbling Standard (BMS) for carcass grading, and the percentage of ether‐extractable fat content in the Longissimus muscle (EE). The difference in the gray level between the Iliocostalis muscle and intermuscular fat (X10) was used to estimate the BMS and the EE, which were highly correlated (r2 = 67.72% and 61.30%). An equation was developed using four parameters from the two ultrasonic images, which could estimate the BMS (r2 = 85.88%). This equation could also estimate the EE (r2 = 68.98%). The equations used to estimate beef marbling were based on one to four parameters that included X10. Thus, ultrasonic images of the Iliocostalis muscle area section are important for estimating beef marbling.  相似文献   
738.
The effect of cross-sectional dimensions on bow and surface checking were investigated, using the boxed-heart square timber of two sugi cultivars with dimensions 80, 120, and 140 mm and length 1.9 m taken at two different heights above the ground. The smaller cross-sectional timber tended to have larger bow, less surface checking, and larger dimensional shrinkage. However, the drying defects were different between the cultivars and sampling heights, depending on the shrinkage properties of the juvenile wood and the heartwood proportion in the core part of the stem. The bow was larger in the smaller cross-sectional timber in which the longitudinal shrinkage was large in the juvenile wood. Surface checking was more prominent in larger cross-sectional timber containing sapwood in its outer part, which suggested the surface checking was induced by drying stress, owing to large moisture gradients between the heartwood and sapwood. The cross-dimensional shrinkage of the timber was larger in timber with larger tangential shrinkage.  相似文献   
739.
ABSTRACT:     The difference in paralytic shellfish poisoning (PSP) toxin accumulation in the crabs Telmessus acutidens and Charybdis japonica was investigated at Onahama, Fukushima Prefecture, from 2002 to 2005. The level of toxin accumulation in the hepatopancreas of T. acutidens corresponded to that of mussels when examined on a yearly basis. In 2003, some crabs had a high toxicity of approximately 1000 MU, which compares to one-third of the human minimum lethal dose. Therefore T. acutidens should be monitored as a vector species of PSP toxin. The toxin profile of T. acutidens was also investigated. Because an increase in highly toxic species of PSP toxins with a decrease in low toxic species, such as N -sulfocarbamoyl-11-hydroxysulfate toxins, was not clearly observed between consecutive samples, toxin transformation in T. acutidens was considered to have a minimal impact on toxicity. PSP toxins were also detected in several specimens of C. japonica , but the highest toxicity was only 7.4 MU/g in the hepatopancreas. Because C. japonica is widely distributed in the coastal waters of Japan, investigation of toxin accumulation in the crab should be continued, including its investigation in different areas of water from Onahama, where the causative dinoflagellates of PSP occur in different conditions.  相似文献   
740.
Aerial and land-based sighting surveys were conducted to clarify the distribution of Steller sea lions during winter in the northern Sea of Japan, along the west coast of Hokkaido, from 2001 to 2003. Aerial surveys revealed that sea lions gathered around the Rishiri-Rebun Islands in March 2002 and 2003, and between Iwanai and Cape Obana in February 2003. Higher numbers of sea lions were also confirmed at Cape Ofuyu and Cape Kamui on the central-west coast compared to that at the haul-out sites in the 1980s on the upper-west coast in March 2002 and 2003. Additionally, fisherman observed sea lions along the coast of the Tsugaru Strait from February to May 2003, where the presence of sea lions was not reported in the 1980s. These facts suggest that sea lions have recently expanded their distribution southward. Land-based surveys at the recent haul-out sites indicated that sea lions in the central-west coast were composed mainly of adult and subadult males (average: Cape Ofuyu 75.2%, Cape Kamui 69.5%), which stayed from November 2002 to May 2003. In this area, sea lions arrived earlier and stayed longer than in the 1980s.  相似文献   
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