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991.
《Veterinary microbiology》2015,175(2-4):382-388
Brucellosis is a zoonotic disease affecting many people and animals worldwide. Preventing this infection requires improving vaccination strategies. The protoxin Cry1Ac of Bacillus thuringiensis is an adjuvant that, in addition to increasing the immunogenicity of different antigens, has shown to be protective in different models of parasitic infections. The objective of the present study was to test whether the intranasal co-administration of pCry1Ac with the RB51 vaccine strain of Brucella abortus confers protection against an intranasal challenge with the virulent strain B. abortus 2308 in BALB/c mice. The results showed that co-administration of pCry1Ac and RB51, increased the immunoprotection conferred by the vaccine as evidenced by the following: (1) decrease of the splenic bacterial load when challenged intranasally with the virulent strain; (2) greater in vivo cytotoxic activity in response to the transference of previously infected cells; (3) further proliferation of cytotoxic TCD8+ cells in response to stimulation with heat-inactivated bacteria; (4) increased production of TNF-α and IFN-γ; and (5) significant IgG2a response. These results indicate that the use of the Cry1Ac protein as a mucosal adjuvant via the intranasal route can be a promising alternative for improving current RB51 vaccine against brucellosis. 相似文献
992.
993.
Cortisol Concentrations in Well‐Regulated Dogs with Hyperadrenocorticism Treated with Trilostane 下载免费PDF全文
J.N. Midence K.J. Drobatz R.S. Hess 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(6):1529-1533
Background
There are no clear treatment guidelines for dogs with clinically well‐regulated hyperadrenocorticism in which serum cortisol concentrations before and after an ACTH stimulation test performed 3–6 hours after trilostane administration are < 2.0 μg/dL.Objective
To determine if serum cortisol concentrations measured before (Pre1) and after (Post1) ACTH stimulation at 3–6 hours after trilostane administration are significantly lower than cortisol concentrations measured before (Pre2) and after (Post2) ACTH stimulation 9–12 hours after trilostane administration, in a specific population of dogs with clinically well‐regulated hyperadrenocorticism and Pre1 and Post1 <2 μg/dL.Animals
Thirteen client‐owned dogs with clinically well‐regulated hyperadrenocorticism and Pre1 and Post1 serum cortisol concentrations <2.0 μg/dL 3–6 hours after trilostane administration.Methods
Prospective study. Dogs had a second ACTH stimulation test performed 9–12 hours after trilostane administration, on the same day of the first ACTH stimulation test. Cortisol concentrations before and after ACTH stimulation were compared using a paired t‐test.Results
Cortisol concentrations before (1.4 ± 0.3 μg/dL) and after the first stimulation (1.5 ± 0.3 μg/dL, mean ± SD) were significantly lower than cortisol concentration before the second stimulation (3.3 ± 1.6 μg/dL, P = .0012 each). Cortisol concentration before the first stimulation was also significantly lower than cortisol concentration after the second stimulation (5.3 ± 2.4 μg/dL, P = .0001).Conclusions and clinical importance
In dogs with clinically well‐regulated, trilostane‐treated, hyperadrenocorticism, and cortisol concentrations <2 μg/dL before and after the first stimulation, a second ACTH stimulation test performed 9–12 hours after treatment can result in higher cortisol concentrations that could support continued trilostane treatment. 相似文献994.
Jiro Sonoda Yuki Seki Atsushi Hakura Satoru Hosokawa 《Journal of toxicologic pathology》2015,28(2):109-120
Benzo[a]pyrene (BP) is mutagenic but noncarcinogenic in the murine colon. Recently, we reported rapid induction of colonic tumors by treatment of CD2F1 mice with BP (125 mg/kg for 5 days) followed by a colitis inducer, dextran sulfate sodium (DSS) (4% in drinking water for 1 or 2 weeks). However, there are no reports on detailed time course and histopathological features of colonic proliferative lesions in this model. Here, we show the detailed time course of colonic dysplasia, adenoma and adenocarcinoma induced by treatment with BP, DSS, and a combination of the two (BP/DSS). In the colon of mice exposed to BP/DSS, 14.6 dysplastic foci per mouse were present one week after DSS treatment (week 4). The number of dysplastic foci decreased with time to 3.1 at week 9 and thereafter remained almost constant. At week 4, 1.5 adenocarcinomas were also observed, with a marked increase in numbers with time, reaching 29.3 at week 14. In contrast, the number of dysplastic foci induced by DSS alone showed a time course similar to that following BP/DSS treatment; however, only a few tumors appeared. Neither dysplastic foci nor neoplastic lesions were induced by BP only. In mice exposed to BP/DSS, β-catenin was demonstrated immunohistochemically in the nucleus and/or cytoplasm of the tumor cells, and this translocation from the cell membrane was evident in subsets of dysplastic foci. In dysplastic foci induced by DSS alone, β-catenin was absent in the nucleus/cytoplasm. These finding suggest that aberrant β-catenin accumulation in dysplastic foci is associated with tumor progression in this BP/DSS model. 相似文献
995.
Anna Kakehashi Akihiro Hagiwara Norio Imai Min Wei Shoji Fukushima Hideki Wanibuchi 《Journal of toxicologic pathology》2015,28(1):27-32
In the present study, in continuation of our previous experiment in order to investigate the mode of action (MOA) of ethyl tertiary-butyl ether (ETBE) hepatotumorigenicity in rats, we aimed to examine alterations in cell proliferation, that are induced by short-term administration of ETBE. F344 rats were administered ETBE at doses of 0, and 1,000 mg/kg body weight twice a day by gavage for 3, 10, 17 and 28 days. It was found that the previously observed significant increase of P450 total content and hydroxyl radical levels after 7 days of ETBE administration, and 8-OHdG formation at day 14, accompanied by accumulation of CYP2B1/2B2, CYP3A1/3A2, CYP2C6, CYP2E1 and CYP1A1 and downregulation of DNA oxoguanine glycosylase 1, was preceded by induction of cell proliferation at day 3. Furthermore, we observed an increase in regenerative cell proliferation as a result of ETBE treatment at day 28, followed by induction of cell cycle arrest and apoptosis by day 14. These results indicated that short-term administration of ETBE led to a significant early increase in cell proliferation activity associated with induction of oxidative stress, and to a regenerative cell proliferation as an adaptive response, which could contribute to the hepatotumorigenicity of ETBE in rats. 相似文献
996.
Yuko TAJIMA Kaori MAEDA Tadasu K. YAMADA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(1):45-51
One hundred and twenty
stranding events of Stejneger’s beaked whales were reported in Japan between 1999 and
2011. The purpose of this study is to introduce pathological data and to discuss probable
causes of death for 44 Stejneger’s beaked whales among them. The significant pathological
findings were the pulmonary edema, parasitic granulomatous nephritis, emaciation,
amyloidosis, suppurative bronchopneumonia and so on. The probable causes of death were
categorized as noninfectious in 43 of the cases, which included drowning, starvation and
secondary amyloidosis. One individual was diagnosed with septicemia, which was the only
example of an infectious disease. Because we could not always perform advanced analyses,
such as microbiology tests, biotoxin examinations or contaminant analyses, the finality of
our findings may be impaired. However, the present study has broad implications on the
causes of death of Stejneger’s beaked whales of the seas around Japan, which are valuable
for the future studies and for the detection of emerging diseases. 相似文献
997.
Ehab MOSSAAD Masahito ASADA Daichi NAKATANI Noboru INOUE Naoaki YOKOYAMA Osamu KANEKO Shin-ichiro KAWAZU 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(1):53-58
Bovine babesiosis is a livestock disease known to cause economic losses in
endemic areas. The apicomplexan parasite Babesia bovis is able to invade
and destroy the host’s erythrocytes leading to the serious pathologies of the disease,
such as anemia and hemoglobinuria. Understanding the egress mechanisms of this parasite is
therefore a key step to develop new therapeutic strategies. In this study, the possible
involvement of Ca2+ in the egress of B. bovis merozoites from
infected erythrocytes was investigated. Egress was artificially induced in
vitro using calcium ionophore A23187 and thapsigargin to increase
Ca2+ concentration in the cytosol of the parasite cells. The increased
intracellular Ca2+ concentration following these treatments was confirmed using
live cell Ca2+ imaging with confocal laser scanning microscopy. Based on our
findings, we suggest a Ca2+ signalling pathway in the egress of B.
bovis merozoites. 相似文献
998.
M. Shamim Hasan ZAHID Sharda Prasad AWASTHI Atsushi HINENOYA Shinji YAMASAKI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(5):535-540
To search natural compounds having inhibitory effect on bacterial growth is important,
particularly in view of growing multidrug resistant (MDR) strains of bacterial pathogens.
Like other bacterial pathogens, MDR Vibrio cholerae, the causative agent
of diarrheal disease cholera, is becoming a great concern. As an approach of searching new
antimicrobial agents, here, we show that anethole, a well-studied natural component of
sweet fennel and star anise seeds, could potentially inhibit the growth of MDR O1 El Tor
biotype, the ongoing 7th cholera pandemic variant strains of toxigenic V.
cholerae. The minimum inhibitory concentration (MIC) of anethole against
diverse O1 El Tor biotype strains is evaluated as 200
µg/ml. Moreover, the effect of anethole is
bactericidal and exerts rapid-killing action on V.
cholerae cells. This study is the first report which demonstrates
that anethole, purified from natural compound, is a potent inhibitor of growth of
toxigenic V. cholerae. Our data suggest that anethole could be a
potential antimicrobial drug candidate, particularly against MDR V.
cholerae mediated infections. 相似文献
999.
Arunee THANASARASAKULPONG Pichayanut POOLPERM Pallop TANKAEW Takuo SAWADA Nattawooti STHITMATEE 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(3):321-326
Recombinant outer membrane protein H (rOmpH) is a potential fowl cholera vaccine
candidate. The present study was aimed at developing rOmpH formulations for intranasal
administration. The rOmpH was purified and formulated with either Escherichia
coli enterotoxin B (LTB) or CpG oligodeoxynucleotides (ODN) as an adjuvant.
Antibody responses in chickens intranasally immunized with rOmpH in combination with 2
different adjuvants were significantly increased (P<0.05) post
immunization. Chicken survival rates showed that rOmpH formulated with ODN and LTB
elicited 90% and 70% protection, respectively. Our findings indicated that rOmpH
formulated with ODN elicited protection better than that formulated with LTB. Therefore,
the vaccines formulations in the present study can be considered new intranasal vaccine
formulations for fowl cholera in chickens. 相似文献
1000.
Zengyang PEI Jinqiu WANG 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(2):139-145
Sepsis is a major cause of mortality in intensive care medicine. Propofol, an intravenous general anesthetic, has been suggested to have anti-inflammatory properties and able to prevent sepsis induced by Gram-positive and Gram-negative bacteria by down-regulating the gene expression of pro-inflammatory cytokines. However, propofol’s anti-inflammatory effects upon canine peripheral blood mononuclear cells (PBMCs) have not yet been clarified. Here, we isolate canine PBMCs and investigate the effects of propofol on the gene expressions of both lipopolysaccharide (LPS)-induced interleukin-6 (IL-6) and tumor necrosis factor (TNF)-α and upon the production of nitric oxide (NO). Through real-time quantitative PCR and the Griess reagent system, we found that non-cytotoxic levels of propofol significantly inhibited the release of NO and IL-6 and TNF-α gene expression in LPS-induced canine PBMCs. Western blotting revealed that LPS
does significantly increase the expression of inducible NO synthase (iNOS) protein in canine PBMCs, while pretreatment with propofol significantly decreases the LPS-induced iNOS protein expression. Propofol, at concentration of 25 µM and 50 µM, also significantly inhibited the LPS-induced nuclear translocation of nuclear factor (NF)-κB p65 protein in canine PBMCs. This diminished TNF-α, IL-6 and iNOS expression, and NO production was in parallel to the respective decreased NF-κB p65 protein nuclear translocation in the LPS-activated canine PBMCs pretreated with 25 µM and 50 µM propofol. This suggests that non-cytotoxic levels of propofol pretreatment can down-regulate LPS-induced inflammatory responses in canine PBMCs, possibly by inhibiting the nuclear translocation of the NF-κB p65 protein. 相似文献