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In plants, flowering is triggered by endogenous and environmental signals. CONSTANS (CO) promotes flowering of Arabidopsis in response to day length. Four early target genes of CO were identified using a steroid-inducible version of the protein. Two of these genes, SUPPRESSOR OF OVEREXPRESSION OF CO 1 (SOC1) and FLOWERING LOCUS T (FT), are required for CO to promote flowering; the others are involved in proline or ethylene biosynthesis. The SOC1 and FT genes are also regulated by a second flowering-time pathway that acts independently of CO. Thus, early target genes of CO define common components of distinct flowering-time pathways.  相似文献   
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Sagittal groove injuries of the proximal phalanx are an important cause of lameness in performance horses. The purpose of this retrospective case series study was to describe standing low‐field magnetic resonance imaging (MRI) characteristics of these injuries in a group of Warmblood horses. Horses with an MRI diagnosis of sagittal groove injuries involving the proximal phalanx and that had follow‐up MRI and clinical outcome information were included. Findings from clinical examinations, diagnostic tests, and other imaging modalities were recorded. All MRI studies were retrieved for re‐evaluation by an experienced, board‐certified veterinary radiologist. A total of 19 horses met inclusion criteria. All horses had MRI lesions consistent with unilateral or bilateral sagittal groove injuries of the proximal phalanx and abnormal mineralization of the sagittal ridge of the third metacarpal/metatarsal bone. Fifteen horses (79%) had concurrent osteoarthritis of the affected metacarpophalangeal/metatarsophalangeal joint. Eighteen horses received conservative therapy and all horses still had osseous abnormalities detected at the time of follow‐up MRI. Thirteen horses (68.5%) were still lame at the time of follow ‐ up, whereas the other six horses (31.5%) had become sound and returned to the previous level of exercise. Findings indicated that, for mature Warmblood horses, acute or chronic injuries of the sagittal groove of the proximal phalanx may have variable standing low‐field MRI characteristics. Based on this sample of 19 horses, findings also indicated that the prognosis for performance soundness in horses diagnosed with sagittal groove injury of the proximal phalanx and concurrent osteoarthritis is poor.  相似文献   
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Reference ranges for triglycerides, insulin, cortisol, and adrenocorticotropic hormone (ACTH) are used in diagnosing hyperlipemia and pituitary pars intermedia dysfunction (PPID) in the donkey. Values are currently compared to reference ranges of the horse so as to diagnose disease. Previous studies found differences between hematological, serum biochemical, and hormone values of the horse and donkey. We suspected that similar differences existed between horse and donkey triglyceride, insulin, cortisol, and ACTH levels. Blood samples were drawn from 44 healthy mammoth donkeys and 1 miniature donkey, ranging in age from 3 weeks to 21 years, and varying in sex and pregnancy status. All but one donkey scored 3 of 5, “ideal,” body condition scoring. Samples were tested for triglycerides, insulin, cortisol, and ACTH levels. A marked difference was found between horse and donkey normal values for triglycerides, insulin, and ACTH. The mean values and standard deviation in the tested population were 66.4 ± 34.2 mg/dL for triglycerides, 2.1 ± 2.05 μU/mL for insulin, and 66.7 ± 20.7 pg/mL for ACTH. The reference ranges in the horse are 14–77 mg/dL for triglycerides, 4.9–45.5 μU/mL for insulin, and 18.7 ± 6.8 pg/mL for ACTH. Cortisol levels were similar in the two species, a 4.0 ± 1.2 μg/dL for donkeys being within the reference range for the horse, 2.9–6.6 μg/dL. Values were not correlated to age. The sample size prevented us from determining any correlation according to sex or pregnancy status. Differences between horse and donkey triglyceride and ACTH values may be significant for accurately diagnosing and treating hyperlipemia and PPID, respectively, in the donkey.  相似文献   
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BackgroundThe repeated administration of high doses of gabapentin may provide better analgesia in horses than current clinical protocols.Hypothesis and ObjectivesAdministration of gabapentin at 40 and 120 mg/kg PO q 12 h for 14 days will not alter serum biochemistry findings or cause adverse effects. Our objectives were to evaluate the effect of gabapentin on serum biochemistry, physical examination, and plasma pharmacokinetics of gabapentin.AnimalsSix healthy adult mares.MethodsHorses received 40 and 120 mg/kg of gabapentin orally q 12 h for 14 days. Horses were examined and scored for ataxia and sedation daily. Serum biochemistry variables were analyzed before treatment and days 7 and 14 after gabapentin administration. Plasma disposition of gabapentin was evaluated after the first and last drug administration. Pharmacokinetic parameters were estimated using noncompartmental analysis.ResultsNo changes occurred in physiologic or biochemical variables. Median (range) maximal plasma gabapentin concentrations (μg/mL) after the last dose (day 15) were 7.6 (6.2‐11) and 22 (14‐33) for 40 mg/kg and 120 mg/kg doses respectively. Maximal concentration of gabapentin was reached within 1 hour after drug administration. Repeated administration of gabapentin resulted in a median (range) area under the curve (AUC0‐12 hours) last/first dose ratio of 1.5 (1.00‐2.63) and 2.92 (1.4‐3.8) for the 40 and 120 mg/kg regimens, respectively.Conclusion and Clinical ImportanceOur results suggest that horses tolerate gabapentin up to 120 mg/kg PO q 12 h for 14 days. The analgesic effect of the dosage regimens evaluated in our study warrants further research.  相似文献   
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Inhibitory conductance changes at synapses in the lamprey brainstem   总被引:1,自引:0,他引:1  
Although the conductance and kinetic behavior of inhibitory synaptic channels have been studied in a number of nerve and muscle cells, there has been little if any detailed study of such channels at synapses in the vertebrate central nervous system or of the relation of such channels to natural synaptic events. In the experiments reported here, current noise measurements were used to obtain such information at synapses on Müller cells in the lamprey brainstem. Application of glycine to the cells activated synaptic channels with large conductances and relaxation time constants (70 picosiemens and 33 milliseconds, respectively, at 3 degrees to 10 degrees C). Spontaneous inhibitory synaptic currents had a mean conductance of 107 nanosiemens and decayed with the same time constant. In addition, the glycine responses and the spontaneous currents had the same reversal potential and both were abolished by strychnine. These results support the idea that glycine is the natural inhibitory transmitter at these synapses and suggest that one quantum of transmitter activates about 1500 elementary conductance channels.  相似文献   
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Gold SS 《Science (New York, N.Y.)》1973,179(4074):656-660
I have stressed the importance of economic growth and employment policies for the furtherance of women's career objectives. Legal action to remove discrimination, as well as transformation of attitudes and expectations, will prove but hollow successes if adequate career opportunities do not become available. For this reason, the employment outlook for professional women in the 1970's has been examined on the basis of three alternative views of the future. All three involve elements of uncertainty and would require adjustments in the labor market. In the first alternative, although the BLS projected an overall balance in the labor market, supply and demand were expected to be ill-matched in several professional sectors, entailing burdensome retraining for those finding themselves in the areas of excess supply. The more pessimistic variant, based either on failure to reach growth and employment goals or on deliberate pursuit of reduced growth goals-combined with population stabilization and increased productivity-would require such fundamental adjustments in the labor market as work-sharing and early retirement or deemphasis of career objectives. The optimistic variant posits economic and social needs great enough to warrant high growth rates and views an expanded labor supply as a factor enabling the economy to attain such growth rates and to extend the utilization of professional personnel in new as well as in established areas (31). The major burden posed by the optimistic variant involves the need to achieve social consensus on the goals of society and to maintain the commitment to those goals with energy and intelligence.  相似文献   
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