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排序方式: 共有431条查询结果,搜索用时 78 毫秒
381.
Hirowatari C Kodama R Sasaki Y Tanigawa Y Fujishima J Yoshikawa T Yabuuchi K Kuwamura Y Hirakawa K Kamimura Y Maeda H 《Journal of toxicologic pathology》2012,25(1):45-49
Porencephaly was observed in a female cynomolgus monkey (Macaca fascicularis) aged 5 years and 7 months. The cerebral hemisphere exhibited diffuse brownish excavation with partial defects of the full thickness of the hemispheric wall, and it constituted open channels between the lateral ventricular system and arachnoid space. In addition, the bilateral occipital lobe was slightly atrophied. Histopathologically, fibrous gliosis was spread out around the excavation area and its periphery. In the roof tissue over the cavity, small round cells were arranged in the laminae. They seemed to be neural or glial precursor cells because they were positive for Musashi 1 and negative for NeuN and GFAP. In the area of fibrous gliosis, hemosiderin or lipofuscin were deposited in the macrophages, and activated astroglias were observed extensively around the excavation area. 相似文献
382.
Hamza HANIEH Kiyoaki NARABARA Yuji TANAKA Zhigang GU Asaki ABE Yasuhiro KONDO 《Animal Science Journal》2012,83(1):68-76
We previously described that supplementary garlic, onion and purple sweet potato (PSP) enhance humoral immune response in White Leghorn chickens. In the present in vitro study, we investigated the effects of garlic (GE), onion (OE) and PSP (PSPE) extracts on proliferation, interleukin (IL)‐2 and interferon (INF)‐γ gene expression of stimulated lymphocytes. The effects on microbicidal activity, reactive oxygen species (ROS) and nitric oxide (NO) productions of stimulated peritoneal macrophages were studied as well. The results showed that GE augmented Concanavalin A (ConA)‐induced splenocytes (4, 8 and 16 µg/mL) and thymocytes (2, 4 and 8 µg/mL) proliferations, and gene expression of IL‐2 (8 and 16 µg/mL) and INF‐γ (16 µg/mL). None of the examined extracts had mitogenic effect nor stimulated bursacytes response to phorbol 12‐myristate 13‐acetate (PMA). Macrophages exhibited superior microbicidal activity and ROS production with GE at 4 and 8 µg/mL and with OE at 25.6 µg/mL. None of the extracts showed stimulatory effects on NO production. The extracts showed concentration‐dependent inhibitory effects on all measured parameters at higher concentrations. Taken together, it is likely that garlic has direct stimulatory effects on immune cell functions, whereas the in vitro inhibitory effects of onion and PSP were likely attributed to high flavonoid contents. 相似文献
383.
Murakoshi F Xiao L Matsubara R Sato R Kato Y Sasaki T Fukuda Y Tada C Nakai Y 《Veterinary parasitology》2012,187(1-2):123-128
Cattle are major hosts of Cryptosporidium spp. Cryptosporidiosis in neonatal calves is associated with retarded growth, weight loss and calf mortality, and zoonotic infections in humans. In many areas, cow-calf glazing system is an important beef cattle rearing method with distinct advantages in terms of cost and the labor required. However, few epidemiologic studies of Cryptosporidium spp. have been conducted in this system, especially using molecular diagnostic tools. To understand the transmission of Cryptosporidium spp. in a grazing system, we followed cryptosporidiosis on a grazing farm in Osaki City, Miyagi Prefecture, in northwest Japan for one year. Fecal samples were collected from Japanese Black and Japanese Shorthorn cattle and examined by PCR-RFLP and sequence analyses. Of 113 fecal samples collected in October 2010, 23 (20%) were positive for Cryptosporidium, including 15 samples (13%) having C. bovis, 6 (5%) having C. ryanae, and 2 (2%) having mixed infections of both species. Additionally, C. bovis or C. ryanae was detected on all other sampling dates involving smaller numbers of animals. The infection rate of C. bovis was significantly different among age groups, and calve-to-calve infection might be the major route of cryptosporidiosis transmission in beef cattle. Interestingly, one animal had C. bovis infection or re-infection for one year. Our results suggest that C. bovis and C. ryanae are distributed in Japan, but might have low level of detection in grazing beef cattle. 相似文献
384.
Ohe K Sakai S Sunaga F Murakami M Kiuchi A Fukuyama M Furuhata K Hara M Soma T Ishikawa Y Taneno A 《Veterinary research communications》2006,30(3):293-305
We analysed genogroups of four feline calcivirus (FCV) isolates (FCV-S, H10, Ao198-1 and ML89) obtained from cats that experienced
FCV infection after having been vaccinated against FCV. New PCR primer sets (8F/8R, Ao-S/Ao-A, cp-S/cp-A) were also designed,
since the conventional Seal primer failed to amplify the target sequences in two samples. The genogroups of the four isolates
as well as eight global and 17 domestic strains were determined by phylogenetic analysis of their amino acid sequences. One
out of the four strains (25%) isolated in this study, H10, was grouped into genogroup I, along with the vaccine strains F9
and FCV-255. The other three isolates (75%) belonged to genogroup II. Thus, there were more isolates in genogroup II than
in genogroup I. However, the antibody values of the four isolates against cat anti-F9 antisera were significantly decreased.
There may be no relationship between the neutralizing antibody titre and genogroup. Amino acid sequence alignment of the four
isolates showed that only a single amino acid in region C, which is involved in neutralization epitopes, was different in
ML89 strain from that of F9. The other three strains, H10, Ao198-1 and FCV-B, shared the same amino acid sequence with F9.
Alignment of amino acids for linear epitopes in the F9 strain, which are located at regions D and E, showed variations in
5' hypervariable region (HVR) of E, whereas D and conE had only synonymous substitutions i.e. no change in the amino acid
sequence. This mutation in 5' HVR of region E suggested a vaccine breakdown, as the region is known to be essential for antigenicity.
The genogroup II FCV is likely to be the cause of the FCV infection in this study, while the vaccine strains belong to genogroup
I. Thus, the existing vaccine may need reevaluation for its effectiveness. 相似文献
385.
In vitro fertilization (IVF) is widely used in reproduction research, but the sperm of some inbred strains of mice yield low fertilization rates in IVF. To determine the cause of this problem, we examined the effect of epididymal sperm morphology, in particular, tail bending and the presence and type of cytoplasmic droplet (CD), on fertilizability in vitro. Sperm suspensions were obtained from the following five strains: C57BL/6J, BALB/cA, C3H/HeN, DBA/2J, and 129 x 1/SvJ. The sperm were fixed in 10% formalin and three parts of the sperm, namely the head, tail, and CD, were examined. We recorded the proportion of abnormal sperm heads and hairpins at the neck; tails were categorized as straight, proximal bent, or distal bent; and the CDs were categorized as none, light-type, and heavy-type. Based on these parameters, we determined the correlations between sperm morphology and fertilizability in vitro, as judged by IVF using ICR oocytes. The proportion of sperm with a hairpin neck was higher in strain C57BL/6J, while abnormal head morphology occurred significantly more often in strain BALB/cA. The percentage of sperm with a proximal bent tail was highest in strain DBA/2J and lowest in strain 129 x 1/SvJ. A heavy-type CD was observed more frequently in the 129 x 1/SvJ and C57BL/6J strains than in the other three strains in which a light-type CD predominated. The rank order of the fertilization rates was 129 x 1/SvJ < C57BL/6J < C3H/HeN < BALB/cA < DBA/2J. In addition, fertilization rate was positively correlated with a proximal bent tail, but negatively correlated with a heavy-type CD and distal bent tail. This new classification system establishes that the morphological characteristics of epididymal sperm differ among inbred strains of mice and that tail and CD morphology are closely related to fertilization ability in IVF. Thus, our results provide a novel method for assessing the quality of mouse sperm used for IVF. 相似文献
386.
Takayuki Matsuura Hirosuke Shinohara Yasuhiro Inoue Koji Azegami Seiya Tsushima Takanori Tsukamoto Akifumi Mizuno 《Journal of General Plant Pathology》2007,73(1):53-58
The phylogenetic relationships among Erwinia amylovora biovar 4 (the pathogen of bacterial shoot blight of pear in Japan), other biovars of E. amylovora, and Erwinia pyrifoliae were investigated using the sequences of 16S rRNA, gyrB, and rpoD genes. The tested isolates formed two distinct monophyletic groups in the phylogenetic trees constructed based on the gyrB gene, rpoD gene, or a combination of the three genes: group 1 contained E. amylovora biovars 1, 2, and 3; group 2 contained E. amylovora bv. 4 and E. pyrifoliae. This phylogenetic analysis showed that E. amylovora bv. 4 was more closely related to E. pyrifoliae than to other biovars of E. amylovora.
The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases under the accession numbers AB242876
to AB242925. 相似文献
387.
Mana Iwamoto Yoji Takeuchi Yasuhiro Takada Shintaro Kohno Isao Matsumoto Naoto Yamaoka 《Journal of General Plant Pathology》2007,73(1):38-40
To determine whether the cuticle of the barley coleoptile is responsible for a rise in appressorial turgor pressure in Blumeria graminis, we determined the appressorial turgor pressure by measuring cytorrhysis and plasmolysis in the presence of PEG6000. Appressorial
turgor pressure significantly increased 13–14 h after inoculation. On the other hand, when the cuticle was completely removed
from the barley coleoptile surface with diethyl ether, turgor pressure did not increase. Moreover, when we then recoated the
surface with the exogenous barley cuticle fraction, appressorial turgor pressure significantly increased 12–13 h after inoculation.
These results suggest that the cuticle on the surface of the barley coleoptile is necessary for the increase in the appressorial
turgor pressure. 相似文献
388.
Koji Azegami Takanori Tsukamoto Takayuki Matsuura Yasuhiro Inoue Hiroshi Uematsu Tatsuji Ohara Akifumi Mizuno Kouji Yoshida Hideo Bessho Shigeyoshi Sato Shigeru Kimura Masao Goto 《Journal of General Plant Pathology》2006,72(1):43-45
Invasion of apple fruit by Erwinia amylovora from fruit-bearing twigs through the abscission layer at fruit maturation was examined. Erwinia amylovora (ca. 105 cfu) tagged with bioluminescence genes from Vibrio fischeri was deposited in artificial wounds on fruit-bearing twigs of apple trees grown in a containment greenhouse on September 22,
27, or October 5, 2004. On October 22, 176 apples were harvested and cut horizontally in half. The upper halves were stamped
on plates of selective medium, and the lower halves were flooded with iodine solution to assess maturity. All fruit were symptomless
and fully mature. The pathogen was recovered from 19 (10.8%) apples. The result showed that if at least ca. 105 cfu of E. amylovora are present in fruit-bearing twigs at the time of fruit maturation, the bacteria can pass through the abscission layer into
the fruit, even though the mature fruit lack symptoms. 相似文献
389.
Hidetoshi Minamiyama Masafumi Shimizu Hitoshi Kunoh Tamotsu Furumai Yasuhiro Igarashi Hiroyasu Onaka Ryuji Yoshida 《Journal of General Plant Pathology》2003,69(1):65-70
An endophytic actinomycete, isolate R-5 of Streptomyces galbus Frommer, that has promising potential as a biocontrol agent was originally isolated from field-grown rhododendron. In this
study, the mode of entry of R-5 into leaves of tissue-cultured seedlings of rhododendron was investigated in connection with
its production of cell wall-degrading enzymes. Light and scanning electron microscopy (SEM) revealed that R-5 grew on leaf
surfaces and entered leaf tissues via stomata and that the internal mycelia grew out of stomata after colonization in host
tissues. Micromanipulation at the SEM level demonstrated a prominent depression in the host surface at the interfaces with
the mycelia, suggesting that such a depression could be caused by degradation of cell wall components by hydrolytic enzymes
secreted from R-5 mycelia. In subsequent plate assays, R-5 produced cellulase, pectinase, xylanase, and nonspecific esterase
when cultured in liquid medium. Moreover, R-5 multiplied in mineral medium containing cellulose, pectin, or xylan as a single
carbon source. Thus, R-5 mycelia could degrade host cell walls at contact sites and probably utilize the degradation products
as carbon sources.
Received: May 16, 2002 / Accepted: July 9, 2002 相似文献
390.
Diurnal variation in thermal environment experienced by salmonids in the North Pacific as indicated by data storage tags 总被引:2,自引:0,他引:2
Robert V. Walker Katherine W. Myers Nancy D. Davis Kerim Y. Aydin Kevin D. Friedland H. Richard Carlson George W. Boehlert Shigehiko Urawa Yasuhiro Ueno & Gen Anma 《Fisheries Oceanography》2000,9(2):171-186
Eight temperature-recording data storage tags were recovered from three salmonids in Alaska (pink and coho salmon and steelhead trout) and five chum salmon in Japan after 21–117 days, containing the first long-term records of ambient temperature from Pacific salmonids migrating at sea. Temperature data imply diel patterns of descents to deeper, cooler water and ascents to the surface. Fish were found at higher average temperatures at night, with narrower temperature ranges and fewer descents than during the day. Fish tagged in the Gulf of Alaska were at higher temperatures on average (10–12°C) than chum salmon tagged in the Bering Sea (8–10°C). Chum salmon were also found at a wider range of temperatures (−1–22°C vs 5–15°C). This is probably related both to the different oceanographic regions through which the fish migrated, as well as species differences in thermal range and vertical movements. Proportions of time that individual fish spent at different temperatures seemed to vary among oceanographic regions. Steelhead trout may descend to moderate depths (50 m) and not be limited to the top few metres, as had been believed. Japanese chum salmon may seek deep, cold waters as they encounter warm surface temperatures on their homeward migrations. Temperature data from all fish showed an initial period (4–21 days) of day and night temperatures near those of sea surface temperatures, suggesting a period of recuperation from tagging trauma. A period of tagging recuperation suggests that vertical movement data from short-term ultrasonic telemetry studies may not represent normal behaviour of fish. The considerable diurnal and shorter-term variation in ambient temperatures suggests that offshore ocean distribution may be linked more to prey distribution and foraging than to sea surface temperatures. 相似文献