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991.
Two inbred strains of Hatano rats, which had been bred selectively on the basis for shuttlebox avoidance responses (high- and low-avoidance animals; HAA and LAA), were different in sperm motility. We have found that there are strain differences in the spontaneous incidence of sperm morphological abnormalities. The percentages of abnormalities were extraordinarily higher in the LAA rats, whose sperm motility was lesser. Since the high sperm abnormality was an exceptional case in rats, these rats may be useful models for sperm quality.  相似文献   
992.
The purposes of this study are to assess the responses of increased supplemental dietary fat in the cow, without upsetting rumen fermentation, on the bile acid (BA) extraction rate in the liver and to determine whether this diet would affect the postprandial lipid profiles in the portal and hepatic venous blood. Six Holstein cows were equipped with catheters fitted in the portal and hepatic veins. Two cows each were assigned randomly to a sequence of three dietary treatments of 21-day period. The methodology of this study was based on the supplementation of the basal concentrate diet with 0 (control), 5, or 10% calcium salts of fatty acids (CSFA). The total bile acids were significantly increased in the portal and hepatic veins with the 5% CSFA diet, whereas no increase occurred with the 10% CSFA diet. Data obtained in this study showed that 10% CSFA diet failed to stimulate BA secretion to exceed the values obtained with 5% CSFA-diet. Moreover, there was no change in the hepatic extraction rate of BA in animals fed either the 0 or 5% CSFA diets which ranged from 2.4 to 6.5-fold and 3.1 to 7.3-fold, respectively. However, the extraction rate increased sharply with the 10% CSFA diet (27-fold). The median portal and hepatic concentrations of total lipids, triglycerides, total cholesterol, phospholipids and non-esterified fatty acids did not show any significant increase during feeding of the control diet. Moreover, feeding either the 5 or 10% CSFA diet did not significantly increase these values in either vein.  相似文献   
993.
Fifteen 5-substituted 1-(6-chloro-3-pyridylmethyl)-2-nitromethylene-1,3- diazacyclohexanes and three other related compounds having a five- or seven-membered ring were synthesized and their biological activities were measured in vivo and in vitro. The insecticidal (in vivo) activity was evaluated against houseflies Musca domestica L under synergistic conditions with propargyl propyl phenyl phosphonate and piperonyl butoxide. The binding activity of each compound to nicotinic acetylcholine receptor in vitro was measured using [125I] alpha-bungarotoxin. The insecticidal activities of the unsubstituted diazacyclohexane analogues were slightly higher than those of the imidazolidine analogues, but the enlargement of ring size to diazacycloheptane lowered the activity. Substitution of 1,3-diazacyclohexane or imidazolidine rings was not generally favourable for the activity, but the unsubstituted 1,3-diazacyclohexane analogue showed the highest binding activity. Ring substitutions and ring enlargement decreased the activity 100-30,000-fold.  相似文献   
994.
Glycophorins are the major sialoglycoproteins in red blood cell membranes, possessing various physiological and pathological roles. We examined membrane glycoproteins in canine red cells and cloned cDNAs for two major glycophorins, glycophorins A (GPA) and C (GPC) from bone marrow cells. Periodic acid-Schiff staining and immunoblotting analyses showed that canine red cell membranes contained several glycoproteins immunoreactive to an anti-bovine GPC antibody, whereas the most abundant sialoglycoproteins, the candidates for GPA, did not react with an anti-human GPA antibody. The amino acid sequences of the extracellular domains of GPA and GPC had no significant homology to those from other mammalian species, including humans, and had O-linked and/or N-linked glycosylation sites. On the other hand, the C-terminal cytoplasmic domain and/or the transmembrane helices of GPA and GPC were conserved among species, indicating some functional significance of those regions in red cell membranes that include dimerization of GPA in the membrane-spanning region, and association of GPC with membrane skeletal proteins through binding with protein 4.1 and p55 in the cytoplasmic domain. These findings provide insights for clinical studies to evaluate the involvement of GPA and GPC in the pathogenesis of red cell diseases.  相似文献   
995.
This study was performed to examine whether the brain activities induced by noxious algesic chemical substances in anesthetized animals could be detected by blood oxygen-level-dependent functional magnetic resonance imaging (BOLD-fMRI). Multislice gradient echo images of the primary somatosensory cortex were obtained using a 7.05 T superconducting system and a one-turned surface coil centered over the primary somatosensory cortex of the 1.0%-isoflurane-anesthetized rat. The Z-score t-map of BOLD signals and its time-course analysis revealed that subcutaneous injection of formalin into the left forepaw immediately induced an early response in the contralateral primary sensory cortex lasting for a few minutes, followed by a late response until 20 min after stimulation. In contrast, injection of capsaicin into the left forepaw evoked only the early response. Furthermore, pretreatment with morphine completely abolished these responses induced by the chemical algesic substances. Thus BOLD-fMRI is a useful method to analyze the brain activities of painful stimulation in anesthetized animals.  相似文献   
996.
Expression of Bcl-2 in feline lymphoma cell lines   总被引:1,自引:0,他引:1  
BACKGROUND: The Bcl-2 gene is a member of the rapidly expanding Bcl-2 family of genes that regulate apoptosis. Bcl-2 has been shown to repress cell death triggered by a diverse array of stimuli, including chemotherapy and gamma irradiation. OBJECTIVE: The purpose of this study was to determine feline Bcl-2 expression level in feline lymphoma cells using an immunoblot assay with anti-human and anti-canine Bcl-2 monoclonal antibodies. METHODS: About 708 base pairs containing the coding sequence of the feline Bcl-2 gene were transformed into Escherichia coli. The recombinant Bcl-2 was used as a positive control for an immunoblot assay using mouse monoclonal antibodies against human and canine Bcl-2. An immunoblot assay using the monoclonal antibodies was carried out to determine the level of feline Bcl-2 expression in lymphoma and lymphocytic leukemia cell lines. RESULTS: The recombinant feline Bcl-2 protein produced in E. coli had a molecular weight of about 26 kDa and was detected by immunoblot assay by using anti-human Bcl-2 mouse monoclonal antibody. Feline Bcl-2 expression was high in lymphoma cell lines (FL-74-UDC-1 and FT-1) and low in the cell line from peripheral blood mononuclear cells from a healthy cat (FeTJ-1) but not low in freshly isolated peripheral blood mononuclear cells from a healthy cat. The anti-human Bcl-2 mouse monoclonal antibody was found to cross-react with feline Bcl-2. CONCLUSIONS: These results confirm the expression of Bcl-2 in T-cell lymphoma cell lines and indicate that it is suitable to detect feline Bcl-2 using an immunoblot assay. Pending further evaluation, Bcl-2 expression might be useful in the differential diagnosis of feline tumors.  相似文献   
997.
We investigated whether suckling would affect embryo production of cows bred by timed artificial insemination (TAI) following an ovulation synchronization protocol combined with ovum pick-up and progesterone releasing intravaginal device (OPU-PRID-TAI protocol). The number of oocytes and transferable embryos collected by repeated OPU, performed before and after TAI, were recorded. A total of 14 Japanese Black cows were divided into weaned (n=7) and suckled groups (n=7). All 14 cows were treated with OPU on day 0 (the first day of treatment) and then with a PRID for 9 days. Prostaglandin F(2alpha) analog was administered on day 7, GnRH analog was administered on day 10 (36 h after removal of the PRID) and TAI was performed 12 h later. Ovulation was confirmed by palpation per rectum the following day. After TAI, additional OPU sessions were performed on days 18, 25 and 32. The synchronized ovulation rates of the weaned and suckled groups were 100 and 85.7%, and the conception rates were 71.4 and 42.9%, respectively. Immature oocytes were fertilized and cultured in vitro. The numbers of oocytes collected and blastocysts generated were similar between the individual OPU sessions in both groups. However, the total numbers of oocytes collected, cultured oocytes, cleavage embryos and blastocysts as well as the proportions of cleavage embryos and blastocysts to cultured oocytes were all significantly (P<0.05) greater in the weaned group compared with the suckled group. These results suggest that the OPU-PRID-TAI protocol has the potential to produce a significant number of good-quality embryos in vitro after repeated OPU in early postpartum weaned Japanese Black cows. To collect more oocytes and produce more embryos, we suggest that calves be removed from cows scheduled for treatment using this protocol.  相似文献   
998.
SUMMARY: The purpose of this study was to evaluate simple alternatives to threshold models within the framework of a mixed-model procedure. Four models-linear model, threshold model, normit-transformation and pseudo-linear model-were compared by Monte-Carlo computer simulation. The normit-transformation model was based on simple normit transformation within a subclass while taking into account binomial error. The simulation experiments were carried out with combinations of five subclass sizes (5, 15, 25, 35, 45), five heritabilities (0.05, 0.15, 0.25, 0.35, 0.45) and 100 replications for each experiment. The loss of accuracy in the prediction models based on binary response was greater than that in the linear model based on continuous records. The accuracy of the threshold model was superior to that of the normit-transformation model and the pseudo-linear model in all the experiments. But the difference in accuracy between the threshold model and the pseudo-linear model was small when the heritability was low and the subclass size was small, while the difference in accuracy between the threshold and the normit transformation was small when the subclass size was large. ZUSAMMENFASSUNG: Vergleich von Michmodell-Voraussagen mittels Monte-Carlo Simulation Die Absicht dieser Untersuchung war die Bewertung einfacher Alternativen für Schwellenwert-Modelle im Rahmen von Mischmodell Methoden. Folgende vier Modelle wurden untersucht: Lineares, Schwellenwert, Normittransformation und pseudo-lineares Modell wurden mittels Monte-Carlo Computersimulation verglichen. Das Normittransformationsmodell beruhte auf einfachen Normittransformation innerhalb einer Unterklasse unter Berücksichtigung des binomialen Fehlers. Die Simulationsexperimente wurden mit fünf Unterklassen-Gr??en (5, 15, 25, 35, 45), fünf Heritabilit?ten (0,05, 0,15, 0,25, 0,35, 0,45) und 100 Wiederholungen für jeden Versuch durchgeführt. Der Genauigkeitsverlust in den Modellen für bin?re Ergebnisse war gr??er als in linearen Modellen mit kontinuierlichen Daten. Die Genauigkeit des Schwellenwert-Modells war der Normittransformation und dem pseudo-linearen Modell in alien Untersuchungen überlegen. Bei geringem h(2) und kleinen Unterklassen war die Genauigkeitsdifferenz zwischen Schwellenwert- und pseudolinearem Modell klein, ebenso wie die zwischen ersterem und Normittransformation bei gro?en Unterklassen.  相似文献   
999.
1000.
The effect of wood kraft pulp (KP) feed on dietary digestibility, ruminal fluid pH, rumen fermentation characteristics, and milk production performance in lactating dairy cows was examined. Four lactating dairy cows were used for the feeding experiment by the cross‐over design. The control group and KP group were set up as treatments. The control group was fed total mixed ration (TMR) (40% roughage and 60% concentrate) and the KP group was fed TMR containing 12% KP that replaced half of the rolled corn in the control diet. The dry matter intake, digestibility of the feed components, and milk yield were not significantly different between control group and KP group. The number of times that the ruminal fluid pH was below 6.1 tended to decrease in the KP group compared to the control group (< 0.10). The acetic acid ratio in the ruminal fluid of the KP group increased compared to the control group (< 0.05) and the propionic acid ratio in the ruminal fluid of the KP group decreased compared to the control group (< 0.05). The acetate:propionate acid ratio was increased in the KP group compared with the control group (< 0.05). Lipopolysaccharide levels in the ruminal fluid of the KP group tended to decrease compared to the control group (< 0.10). Based on these results, it was indicated that the use of KP feed for lactating dairy cows induced the same rumen fermentation characteristics as those in cows given a large amount of roughage without depressing milk productivity. Therefore, KP could be a valuable feed resource substitute for grains, which would also reduce the risk for subacute rumen acidosis.  相似文献   
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