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121.
Cervical vertebral interbody fusion was performed on 30 horses affected with cervical vertebral malformation (CVM) or "wobbles" to assess the efficacy of the surgery in either preventing progression of or reversing the neurologic deficit induced by the syndrome. Evaluation of each horse prior to surgery included clinical, radiographic, neurologic, and laboratory examination. Subjects ranged from 3 months to 8 years of age, and included 22 males and 8 females of various breeds. Three normal horses were included as controls. The Cloward method of cervical fusion was used to achieve stabilization at the affected vertebral articulation. Horses were reexamined 3 months after surgery. Clinical improvement was seen in 90% (27 of 30) of the cases. Four horses were returned to training, which had been interrupted by onset of symptoms. Seven were returned to owners as breeding animals. Twelve horses were kept for long-term studies. Seven horses were sacrificed to examine the surgical site. In 6 of the 7 horses on which necropsy was performed, the most severe histologic lesion in the spinal cord could be predicted from lesions seen radiographically. The spinal cords of control animals were normal. Osseous fusion was dependent on the completeness of removal of disc fibrocartilage during surgery. We conclude that clinical improvement in some horses affected with CVM can be achieved by cervical fusion.  相似文献   
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123.
The ocular distribution of kanamycin following intramuscular, bulbar subconjunctival injection, or after constant rate intravenous infusion to calves was studied. Steady-state plasma concentrations of kanamycin were achieved in either normal calves, or in those experimentally infected with Moraxella bovis, and the concentrations of kanamycin in the serum, aqueous humor, vitreous body, tears, and the ocular tissues were measured. Kanamycin was not detected in the retina, lens, vitreous body, or the aqueous humor of any eyes, but the concentration of drug in the tears, conjunctiva, cornea and the orbital lacrimal gland of these calves ranged between 18 and 21% of that in serum. At steady-state plasma levels, the kanamycin concentrations in tears from eyes with keratoconjunctivitis and from normal eyes were similar. A study using lyophilized, powdered, ocular tissues in vitro showed that kanamycin was highly bound to the bovine retina and iris, and could be eluted using 0.2 N NaOH. The binding of kanamycin to other ocular tissues, including cornea, conjunctiva and lens, was significantly less. The concentration of kanamycin in the serum and the tears of calves was also measured after intramuscular or bulbar subconjunctival injection. After intramuscular administration of kanamycin (10 mg/kg of body-weight), the mean serum concentration was maximal at 1 h (32 micrograms/ml) and remained greater than or equal to 1.0 microgram/ml for 8 h. The mean tear concentration was maximal (3.1 micrograms/ml) at 30 min, and remained greater than or equal to 1.5 micrograms/ml for only 2.5 h. Following bulbar subjunctival administration of kanamycin (100 mg, single subconjunctival dose), the mean tear concentration was 1127 micrograms/ml at 30 min, less than or equal to 4.1 micrograms/ml at 4 h, and thereafter was less than or equal to 1.0 microgram/ml. It was concluded that kanamycin has limited distribution to the ocular tissues following parenteral administration. Binding of the drug to the ocular pigments may be responsible for its limited intraocular penetration.  相似文献   
124.
An 11-year-old, 43 kg neutered female Labrador retriever dog developed acute pelvic limb paraparesis. In magnetic resonance images there was a T1- and T2-hyperintense extradural at the fifth thoracic intervertebral space that was causing marked compression of the spinal cord. In short tau inversion recovery and fat suppressed T1-weighted images the signal from the mass was decreased indicating it was of fatty origin. The mass was removed via a dorsal hemilaminectomy in the thoracic area. Histopathologic analysis confirmed the mass was an infiltrative lipoma. The dog recovered and is fully ambulatory 24 months after surgery. This report provides additional evidence that lipomas in the vertebral canal may be the source of pelvic limb neuropathy and also illustrates the value of magnetic resonance imaging in establishing the fatty nature of some soft tissue masses.  相似文献   
125.
Dynamic helical computed tomography (CT) of the pituitary gland can be used to image the three-dimensional shape and dimensions of abnormalities within the pituitary gland. The aim of this study was to develop a protocol for dynamic helical CT of the pituitary gland in healthy dogs as a future reference study for patients with pituitary disease. Dynamic helical series of nine scans of the pituitary gland during and following contrast medium injection were performed in six healthy dogs using the following protocols: a series with 1 mm collimation and a table feed per X-ray tube rotation of 2 mm (pitch of 2) in six dogs, a series with 2 mm collimation and pitch of 2 in three dogs, and a series with 1 mm collimation and pitch of 1 in three other dogs. Multiplanar reconstructions of the images were made using a reconstruction index of 0.5. Images of all series were assessed visually for enhancement of the arteries, the neurohypophysis, and the adenohypophysis. The enhancement pattern of the neurohypophysis was distinguished adequately from that of the adenohypophysis in five dogs that were scanned with 1 mm collimation and pitch of 2, but the difference was less discernable when the other protocols were used. The carotid artery, its trifurcation, and the arterial cerebral circle were best visualized in dorsal reconstructions. Dynamic helical CT of the pituitary gland in healthy dogs can be performed with 1 mm collimation and pitch of 2, and a scan length that includes the entire pituitary region. Using this protocol, with the specific scanner used, the neurohypophysis, the adenohypophysis, and the surrounding vascular structures are adequately visualized.  相似文献   
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127.
The influence of global greenhouse warming on the ocean's biological productivity may be more complicated and weaker than that proposed by Bakun (1990). A doubled carbon dioxide simulation made with the Canadian Climate Centre atmospheric general circulation model coupled to a simplified mixed layer ocean model suggests that the midlatitude continents do not all follow the Bakun scenario in developing anomalous low pressure in summer and enhancing coastal winds favorable to upwelling. In the open ocean the equatorial and subpolar zonal upwelling bands and the subtropical downwelling bands generally weaken as winds diminish owing to the weakening of the equator-to-pole temperature gradient in the lower troposphere under global warming. With a weakening of open ocean upwelling and an absence of enhanced coastal upwelling, the overall effect of global warming could be to decrease the global biological productivity.  相似文献   
128.
Different sources of DHA and/or n-3 (omega-3) rich oils, oil emulsions and microencapsulated (ME) powders were tested at two different concentrations with the aim of producing fortified pan bread. Three oils (S-algae, fish and flax), two emulsified algae oils (Emulsion-P and Emulsion-L) and two ME oils (ME-S algae and ME-C algae) were compared. The DHA and n-3 oils replaced part of the shortening in order to obtain 32 g slices enriched with 25 or 50 mg DHA, 35 or 70 mg total n-3 from fish oil and 90 or 180 mg linolenic from flax oil. Addition of oils did not significantly affect water absorption but reduced mix time whereas addition of the ME oils decreased both water absorption and mix time. Breads enriched with flax or ME-C oils had lower volume and higher density than the control, ME-S algae, Emulsion-P and Emulsion-L breads. All breads lost texture throughout 14 d storage, the major changes occurred after 3 d. The ME-S algae oil bread had the best softness after 14 d storage whereas breads produced from ME-S algae or ME-C algae oils had the poorest texture. Sensory evaluations indicated that the color of the ME-S algae oil fortified bread was significantly less preferred than the other loaves. After 6 d the control bread had higher acceptability compared with the rest of the breads enriched with high levels of DHA or omega-3 oils. The high-enriched fish oil bread was well accepted during the first days of storage but had the least preferred acceptability after 13 d. The best fortified breads were those supplemented with S-algae oil, Emulsion-P and Emulsion-L oils.  相似文献   
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