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191.
An ultrasonographic reproductive health examination of a 26-yr-old female African elephant (Loxodonta africana) revealed bilateral ureteral wall thickening and dilatation. On ultrasonographic examination, the bladder and both ureters were normal near the trigone; however, the cranial-most aspect of each ureter was dilated and thickened for a length of 30-50 cm. The same month, elevated blood creatinine (3.0 mg/dl), and urine protein-creatinine ratio (4.0) were observed. Chronic renal failure was diagnosed based on these abnormalities, and the persistent ureteral dilatation was seen on subsequent ultrasound examinations. Complete blood cell counts, serum chemistries, and urinalyses remained relatively unchanged until 24 mo after diagnosis, at which time azotemia, hypophosphatemia, and hypercalcemia (including elevated ionized calcium) developed. Hydronephrosis of both kidneys and prominent sacculation of the left ureter were noted on ultrasonographic examination. Lethargy, ventral edema, and oral mucosal ulceration acutely developed 30 mo after diagnosis. Although blood urea nitrogen remained elevated, creatinine, total calcium, and ionized calcium returned to within reference ranges at that time. Due to rapid clinical decline and grave prognosis, humane euthanasia was elected. Bilateral ureteral dilatation, dysplasia of the right kidney, and chronic nephritis of the left kidney were identified postmortem.  相似文献   
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193.
Three wheat antioxidant fractions were investigated for their potential effects on oxygen diffusion-concentration products in liposomes prepared with egg yolk phosphatidycholine (yolk PC) and rat liver PC (liver PC), using the electron spin resonance (ESR) oximetry method with 2,2'-azobis(2-aminopropane) dihydrochloride (AAPH) and 2,2'-azobis(2,4-dimethylvaleronitrile) (AMVN) as radical generators. Both water-soluble wheat antioxidant (WWA) and the second lipophilic antioxidant (LWA2) fractions were able to inhibit oxygen diffusion-concentration product induced by either AAPH or AMVN. The first lipophilic wheat antioxidant (LWA1) fraction only showed antioxidant activity in yolk PC liposomes with AAPH as the radical initiator but had pro-oxidant activity under other testing conditions. Both liposome composition and radical initiator altered the antioxidative properties of WWA, LWA1, and LWA2. WWA also showed the strongest DPPH(*) scavenging capacity on a per grain weight basis. HPLC analysis showed that WWA had a much higher level of total phenolic acids, which may partially explain their antioxidant properties. In addition, wheat antioxidants significantly down-regulated the mRNA of HMG-CoA reductase, the key enzyme for cholesterol biosynthesis, and up-regulated the mRNA of cholesterol 7alpha-hydroxylase (CYP7A1), the key enzyme for cholesterol metabolism, in primary rat hepatocytes. These data indicated the potential of wheat antioxidants in reducing the risk of atherosclerosis through multimechanisms.  相似文献   
194.
The amino acid sequence of bovine somatotropin (bST) varies at position 127 where either valine or leucine is found. The frequencies of leucine127 and valine127 bST gene alleles in cows (n = 302) and sires (n = 70) from major dairy breeds (Holstein, Brown Swiss, Guernsey, Jersey, and Ayrshire) were determined using DNA extracted from whole blood or spermatozoa. A 428 base pair fragment of the bST gene was amplified using polymerase chain reaction (PCR) and variants of the bST gene were detected as polymorphisms by Alu I restriction endonuclease digestion of PCR products. Restriction enzyme DNA fragments for the leucine127 variant were 265, 96, 51, and 16 base pair and for the valine127 variant were 265, 147, and 16 base pair as a polymorphism of bST was present in the 147 base pair DNA fragment. Frequencies of leucine127 and valine127 alleles for cows (n=302) were 1.0 and 0 for Brown Swiss, .93 and .07 for Holstein, .92 and .08 for Guernsey, .79 and .21 for Ayrshire, and .56 and .44 for Jersey, respectively. In Holstein sires used for artificial insemination (n=70), the frequency of leucine127 and valine127 alleles was .96 and .04. Estimates of transmitting ability for milk production tended to be greater for Holstein cows that were homozygous for leucine127 bST and Jersey cows that were homozygous for valine127 bST whereas Holstein sires with different bST genotypes were similar. In summary, frequencies of alleles for the bST gene were not similar in different dairy breeds and estimates of milk production were correlated with bST gene variant in cows but not sires.  相似文献   
195.
196.
The presence of anti-insulin antibodies was determined by ELISA in serum samples from 30 diabetic dogs receiving bovine insulin therapy and 30 normoglycaemic dogs. Twenty of the diabetic dogs had significant reactivity to both bovine (heterologous) and porcine (homologous) insulin compared to control dogs. In contrast there was no significant difference between the two populations in reactivity to canine distemper virus (CDV) or canine thyroglobulin. The high degree of correlation between anti-bovine insulin and anti-porcine insulin antibodies suggested cross-reactivity which was confirmed by performing a competition ELISA, with antibody binding to bovine insulin inhibited by pre-incubating serum with porcine insulin. The insulin B-chain, rather than the A-chain was the most reactive component of the insulin molecule although in some cases, diabetics with antibody reactivity to whole insulin protein showed minimal reactivity to the individual subunits. The data suggest that treatment of diabetic dogs with bovine insulin can lead to anti-insulin antibody production. These antibodies cross-react with homologous insulin and recognise conformational as well as linear epitopes.  相似文献   
197.
In order to determine if vertically transmitted porcine circovirus (PCV) has played a role in reproductive failure in pigs in areas of endemic infection, archival fixed tissues were examined by polymerase chain reaction (PCR) and immunohistochemistry. Tissues tested were from routine cases of abortion or reproductive failure submitted between 1995 and 1998 to the diagnostic laboratory at the Western College of Veterinary Medicine, Saskatoon. They originated from 29 high-health herds in the provinces of Alberta and Saskatchewan and comprised a total of 36 individual submissions. Porcine circovirus type 1 (PCV1) was not detected by PCR in any submitted tissues. Porcine circovirus type 2 (PCV2) was not detected by PCR or immunohistochemistry in any of the submitted tissue. The effect of extended formalin fixation on the detection of PCV2 by PCR was assessed and fixation for up to one week had no gross effect on sensitivity of detection using this PCR technique. Failure to detect porcine circoviruses in cases of reproductive failure prior to 1999 in areas of endemic infections, suggests that reproductive disease may be a new clinical manifestation of PCV2 infection, and that vertical transmission may not have been the primary mechanism of initial dissemination of the virus in the pig population.  相似文献   
198.
A method is described for simultaneous recording of in-vivo nerve activity and toxicological symptoms from 6th-instar larvae of Spodoptera littoralis poisoned with insecticide. Topically applied doses (9 ng-180 μg insect?1) of cypermethrin induced hyperactivity, repetitive activity and bursting in the ventral nerve cord; these activities were associated with different stages of poisoning in the whole animal and are consistent with pharmacokinetic studies. Nerve activity continued long after the larvae appeared to be dead (i.e. up to 5-6 days), although microscopic examination of these larvae revealed that they were still capable of small movements. At the lower doses (up to the LD95) time to death was inversely proportional to dose. Death of the organism may be related to the number of neurones which are affected by the insecticide.  相似文献   
199.
Two adult California sea lions (Zalophus californianus) were effectively anesthetized 13 times with medetomidine (0.010-0.013 mg/kg), midazolam (0.2-0.26 mg/kg), and butorphanol (0.2-0.4 mg/kg) by i.m. hand or pole syringe injection. For each anesthetic event, atropine (0.02 mg/kg, i.m.) was administered 6-20 min after initial injections, and oxygen administration via face mask or nasal insufflation began at the same time. Light anesthesia was induced in 8-22 min and lasted 13-78 min. During eight of the procedures, isoflurane (0.5-2.0%) was administered via face mask or endotracheal tube for an additional 30-120 min to facilitate longer procedures or surgery. Anesthesia was antagonized with atipamezole (0.05-0.06 mg/kg) and naltrexone (0.1 mg/kg) in seven events, with the addition of flumazenil (0.0002-0.002 mg/kg) in six events. The antagonists were administered by i.m. injection 42-149 min after administration of the induction agents. All sea lions recovered to mild sedation within 4-17 min after administration of the antagonists.  相似文献   
200.
The sequential tissue distribution of virus was investigated using virus isolation and immunofluorescence tests in 1-day-old piglets inoculated with porcine circovirus 2 (PCV2) and/or porcine parvovirus (PPV). Enlarged mesenteric lymph nodes were seen in the pig inoculated with PCV2 alone and killed at 26 days post-inoculation (PI). One of the pigs inoculated with PCV2 and PPV and killed at 21 days PI had an enlarged liver. The pig killed at 26 days PI in this group had enlarged liver, kidneys and heart. Histopathological changes were seen in lymphoid tissues of the pigs inoculated with PCV2 alone and killed at 14 and 26 days PI. Similar, but more severe, lesions were observed in the pigs infected with PCV2 and PPV and killed from 10 days PI onwards. Histological lesions of nephritis, pneumonia and hepatitis were also apparent in these animals. Mild nephritis was also seen in the pigs infected with PPV alone and killed at 14 and 26 days PI. Moderate amounts of PPV antigen were detected in tissues from the pigs inoculated with PPV alone and killed at 14 days PI. Low levels of PCV antigen were detected, mainly in lymphoid tissues, in the pigs inoculated with PCV alone and killed at 14 days PI. Low to moderate amounts of PCV antigen were detected in a wider range of tissues in the pig in this group killed at 26 days PI. In the pigs inoculated with both viruses, PPV antigen was detected in tissues of pigs killed from 3 to 26 days PI with maximal amounts detected between 6 and 14 days PI. PCV2 antigen was detected in low to moderate amounts in the tissues of pigs killed at 14 days PI. Large amounts of PCV2 antigen were detected in most of the tissues from pigs in this group killed between 17 and 26 days PI. Virus isolation results for PCV2 generally correlated well with the results for immunofluorescent staining. PPV was isolated from almost all tissues from pigs inoculated with PCV2 and PPV, a much higher incidence of positive tissues than observed for immunofluorescent staining.  相似文献   
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