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1.
    
Latissimus dorsi and cutaneous trunci myocutaneous flaps of equal dimension and location were randomly elevated on opposite sides of the thorax in 10 dogs (group 1) and resutured to their respective bed. The procedure was repeated in four additional dogs (group 2); however, the short perforating branches of the thoracodorsal artery and vein were divided at the base of each cutaneous trunci myocutaneous flap, whereas the cutaneous pedicle and underlying cutaneous trunci muscle were divided in the latissimus dorsi myocutaneous flaps to determine subsequent skin survivability and the major source of circulation of each myocutaneous flap. There was little difference in the percentage of skin survival between the latissimus dorsi and cutaneous trunci myocutaneous flaps in group 1 dogs. Circulation to the \"skin island\" of group 2 latissimus dorsi myocutaneous flaps originated from intramuscular anastomotic connections between the major branch of the thoracodorsal artery entering the latissimus dorsi muscle and the proximal lateral intercostal arteries perforating the muscle. Ligation of the short perforating branches of the thoracodorsal artery resulted in partial skin necrosis in all group 2 cutaneous trunci myocutaneous flaps. Results from this study indicate that it is unnecessary to elevate the latissimus dorsi muscle for major skin flap elevation and survival. The thicker latissimus dorsi myocutaneous flap is more difficult to develop surgically and appears to have no clinical major advantage over the more mobile cutaneous trunci myocutaneous flap or the adjacent thoracodorsal axial pattern flap for closure of large skin defects within the radius of flap rotation.  相似文献   
2.
    
Iridocorneal angle abnormalities were detected by gonioscopy in five dogs and one cat with glaucoma and intraocular neoplasms. Gonioscopic photographs and the histological abnormalities were compared in the neoplasia cases (the cat and two dogs). Congenital mesodermal, iridocorneal angle anomalies may occur more frequently in canine glaucoma than previously suspected.
Résumé. La gonioscopie a permis de déceler des anomalies de l'angle irido-corntén chez cinq chiens et un chat atteints de glaucome et de néoplasies intraoculaires. Les photographies gonioscopiques et les anomalies histologiques ont été comparées chez les animaux porteurs de néoplasmes (le chat et deux chiens). Des anomalies mésodermiques congénitales de l'angle irido-cornéen peuvent s'observer dans le glaucome du chien dans une proportion de cas plus grande qu'on ne l'admettait jusqu'ici.
Zusammenfassung. Mittels Gonioskopie wurden bei fünf Hunden und einer Katze mit Glaukom und intraokularen Neoplasmen iridocorneale Winkelanomalien festgestellt. Die gonioskopischen Photographien und die histologischen Anomalien wurden in den Neoplasmen-Fällen (die Katze und zwei Hunde) verglichen. Kongenitale mesodermale Anomalien des iridocornealen Winkels können beim Glaukom des Hundes haufiger auftreten als bisher angenommen wurde.  相似文献   
3.
4.
Experiments with tick-paralyzed dogs and woodchucks have shown impairment of stretch reflexes in addition to partial paralysis at the neuromuscular junction. Stretch reflexes disappear very early during paralysis, whereas nociceptive reflexes do not appear to be directly affected. The early incoordination and the ascending nature of the paralysis may be related to impairment of stretch reflex pathways.  相似文献   
5.
    
Intramedullary masses are a dilemma due to the limited access for a nonsurgical biopsy, thus, accurate imaging characterization is crucial. Magnetic resonance imaging findings of two confirmed canine thoracic intramedullary hemangiomas are described. A capillary hemangioma was of mixed intensity but predominantly T2‐hyperintense and mildly T1‐hyperintense to spinal cord with strong contrast enhancement. A cavernous hemangioma had a target‐like appearance in both T1‐weighted (T1w) and T2‐weighted (T2w) images. In T2w images there was a small isointense center surrounded by a relatively large hyperintense area. In T1w images, there was a large isointense centre with a relatively small hyperintense periphery. Such characteristics should prioritize hemangioma as a consideration in a progressive myelopathy due to an intramedullary mass.  相似文献   
6.
Objective— To report the prevalence of hypophosphatemia after renal transplantation in a historical cohort of cats. Design— Case series. Animals— Cats (n=86) that received a renal allograft. Methods— Medical records (January 200–June 2006) were reviewed. Signalment, clinical signs, pre‐ and postoperative diet, pre‐ and postoperative clinicopathologic variables, renal histopathology, and outcome were retrieved. Prevalence, onset, duration, treatment and associated clinical signs of hypophosphatemia were recorded. A χ2 test was used to compare hemolysis frequency between cats with normal serum phosphorus concentration or a single spurious low serum phosphorus concentration for <24 hours duration (group 1) and confirmed hypophosphatemia for >24 hours (group 2). A Cox proportional hazards model was used to evaluate the effects of hypophosphatemia on survival while controlling for other potentially confounding variables (age, sex, weight, body condition score, and pre‐ and 24 hours postoperative clinicopathologic variables). Results— Eighty‐six cats (mean age, 7.7 years) were identified. Hypophosphatemia occurred in 32 cats (37%), with a median onset of 2 days and median duration of 4 days. Treatment was initiated in 48 (56%) of hypophosphatemic cats. Survival and hemolysis frequency was not significantly different between groups, and no risk factors were identified. Conclusion— Hypophosphatemia occurs in cats after renal transplantation and does not affect survival. Clinical Relevance— The clinical importance of hypophosphatemia in renal transplant recipients remains unknown.  相似文献   
7.
PHILIP  M. S. 《Forestry》1975,48(2):123-138
The use of simulation as a tool in planning, predicting output,and as part of a system of forest management is discussed andillustrated by an example based on thirty-seven privately ownedforest estates in the Dee valley in north-east Scotland. The simulation model is described and the results of a low anda high level of felling and afforestation are compared. Thepredicted outputs from the simulation runs are compared withthe records of actual output from 1970 to 1972. The estimated increment and output were: Annual increment of crops 20 years and older 52,000 m3 Annual output at the ‘high’ level .4,000 m3 Annual output at the ‘low’ level 27,000 m3 Average actual annual output 1970–2 18,000 m3 The conclusions drawn from the results of the management studyin the forests of the Dee valley are:
  1. In the past, owners haveaccepted low rates of return from theirforest enterprise, theirprimary object being to re-create andmaintain a forest resourcesimilar to that which existed inthe past.
  2. Objective reappraisalsof the forest enterprise are exceptionaland management is constrainedoften by arbitrary, rigid, andsevere decisions that imposeunforeseen consequences on activitiesin both the forest andother parts of the estate.
  3. The current situation of the forestis very different from thatof the past and is continually changing.For example, the demandsof modern marketing and harvestingpractices are quite differentfrom those imposed even ten yearsago, and the proposed Wealthand Capital Transfer Taxes mayalter the relative importanceto the owners of forest incomeand capital.
Many forest owners in Britain now require a more objective approachto forest management with continuous reappraisal to ensure thattheir plans continue to serve their needs. As the financialresults of the forest enterprise are especially sensitive tothe felling and afforestation programmes, studies to answerthe following questions may be needed urgently:
  1. Can a higheroutput than that harvested at present be sustainedin the future?
  2. Should the rate of replacement of mature woods be altered?
  3. Does the current rate of afforestation best serve the objectsof management in the light of altered tax commitments and cashliquidity requirements?
Computer simulation can be a useful aid in planning providedthat reliable information on costs, prices, and growth ratesis available. Forest managers must be encouraged to collectthe necessary data.  相似文献   
8.
In the more than 50 years that the Continuous Plankton Recorder (CPR) survey has operated on a regular monthly basis in the north-east Atlantic and North Sea, large changes have been witnessed in the planktonic ecosystem. These changes have taken the form of long-term trends in abundance for certain species or stepwise changes for others, and in many cases are correlated with a mode of climatic variability in the North Atlantic, either: (1) the North Atlantic Oscillation (NAO), a basin-scale atmospheric alteration of the pressure field between the Azores high pressure cell and the Icelandic Low; or (2) the Gulf Stream Index (GSI), which measures the latitudinal position of the north wall of the Gulf Stream. Recent work has shown that the changes in the GSI are coupled with the NAO and Pacific Southern Oscillation with a 2 year lag. The plankton variability is also possibly linked to changes observed in the distribution and flux of water masses in the surface, intermediate and deep waters of the North Atlantic. For example, in the last two decades, the extent and location of the formation of North Atlantic Deep Water, Labrador Sea Intermediate Water and Norwegian Sea intermediate and upper-layer water has altered considerably. This paper discusses the extent to which observed changes in plankton abundance and distribution may be linked to this basin-scale variability in hydrodynamics. The results are also placed within the context of global climate warming and the possible effects of the observed melting of Arctic permafrost and sea ice on the subpolar North Atlantic.  相似文献   
9.
    
The accuracy of diagnoses based on examination of frozen sections was determined by comparing the results to those obtained by examination of tissues prepared using conventional methods (formalin fixation, paraffin-embedded tissue). One hundred ninety-four specimens were examined using the frozen section technique; 37 were examined to confirm a tentative diagnosis or to document lymph node metastasis and the remainder were examined to diagnose an unknown pathologic process. Of the 194 specimens examined, an accurate, specific diagnosis was obtained in 161 (83%); in 19 (10%), the pathologic process was correctly identified, but a specific diagnosis was not obtained; and in 2 (1%) the diagnosis was deferred. The remaining 12 (6%) were incorrectly diagnosed by the frozen section technique. When the number of specimens in which a specific diagnosis was obtained was combined with the number of specimens in which the pathologic process was correctly identified, the overall accuracy rate of the frozen section technique was 93%. There was no difference in the accuracy of the frozen section technique based on the reason for submission of the sample, source of tissue submitted, or the type of pathologic process (i.e., inflammatory or neoplastic). Of the 12 incorrect diagnoses, 4 (33%) were because of sampling errors and 8 (67%) were caused by interpretation errors. The proposed indications for the use of intraoperative frozen sections are: 1) to determine the nature of a pathologic process for which a preoperative diagnosis has not been established, 2) to determine the extent of spread of neoplastic tissue to lymph nodes and other organs, 3) to evaluate resection margins of a neoplastic process, and 4) to clarify situations where a discrepancy exists between the preoperative cytologic or histologic diagnosis and intraoperative gross pathology.  相似文献   
10.
Prawn shell waste collected from shrimp‐processing plants in Cochin, India, was subjected to fermentation using 20 chitinoclastic and proteolytic/non‐proteolytic bacterial strains. The products generated were analysed for protein, lipid, total sugars, N‐acetyl glucosamine, free amino acids and ash. Shrimp diets were prepared using these 20 fermented products and a control diet using raw prawn shell waste. Feeding experiment was conducted with postlarvae (PL21) of Indian white prawn, Fenneropenaeus indicus for a period of 21 days. Biogrowth parameters such as mean weight gain, feed conversion ratio, specific growth rate and protein efficiency ratio were estimated and the animals were challenged with white spot virus orally via diet. Enhanced growth could be observed in prawns fed F134 and F124, incorporated with the fermentation products generated using Bacillus spp., C134 and C124 respectively. The percentage survival of prawns after 7 days of challenge was found to be highest for groups fed diet F111 incorporated with fermentation product generated using Bacillus sp. These products of bacterial fermentation hold promise as growth enhancers and immunostimulants in aquaculture.  相似文献   
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