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61.
Forty-two cats underwent craniotomy for removal of a meningioma between 1985 and 1991. Median duration of clinical signs before examination was 1.25 months. All cats had inappropriate demeanor: 48% were dull and 38% were lethargic. Neurological deficits included impaired vision in 93%, paresis in 83%, and seizures in 19%. Computed tomography (CT) showed solitary masses in 86% and multiple masses in 14%. Intraoperative complications included hemorrhage and difficulty excising deep or adherent masses. Anemia in 13 of 42 cats was the most common immediate postoperative complication. Ten of 42 cats had no improvement or a more severe neurological status after surgery. Eight of 42 cats died immediately after surgery; 6 of these were anemic. Of the cats that survived the immediate postoperative period, evaluation 10 to 14 days after surgery showed that 97% (33 of 34) were alert and 79% (27 of 34) had returned to normal behavior. Neurological deficits, except for vision impairment, had resolved in most cats. The duration of follow-up varied from 1.3 months to 55.1 months. Ten cats developed neurological abnormalities from 1 month to 44.2 months after surgery; of these, 6 had tumor recurrence or new growth confirmed by CT scan or necropsy. Overall survival was 71% at 6 months, 66% at 1 year, and 50% at 2 years. Age of cat and location of tumor did not significantly affect survival ( P = . 1034 and .1851, respectively). There were too few precise measurements of tumor size to make a valid statistical comparison of the effect of size on survival. Location or presence of multiple tumors did not affect final outcome. Results of this study indicate that surgical excision is a beneficial method of treatment of cranial meningioma in cats.  相似文献   
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63.
Jejunojejunal intussusception occurred after jejunal resection and stapled functional end-to-end anastomosis in two pony mares. In both mares, the lead point of the intussusception was the stapled functional end-to-end (FEE) anastomosis. The stapled free ends of jejunum were oversewn with an inverting suture pattern. A possible explanation for development of the intussusception was the acute angle created in the intestine by the FEE anastomsis. This angulation may have impaired flow of ingesta causing motility changes that predisposed the site to intussusception. Because the oversewn blind intestinal ends acted as the lead point for formation of the intussusception, it may be inadvisable to oversew the stapled anastomotic ends.  相似文献   
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65.
Cryosurgical treatment of canine eyelid neoplasms has resulted in destruction of the tumors while maintaining acceptable cosmetic results. Both clinical experience and experimental studies have shown the normal canine palpebra to be quite resistant to excessive permanent deformity secondary to freezing. Significant histologic changes after cryotherapy are loss of adnexal structures, and depigmentation and thinning of the epithelium. Cryosurgery is recommended as an alternative treatment to surgical excision of eyelid tumors in dogs.  相似文献   
66.
Morphologic Effects of Experimental Distention of Equine Small Intestine   总被引:1,自引:0,他引:1  
The morphologic effects of induced intraluminal hydrostatic pressures (IHPs) of 0, 9, and 18 cm H2O were evaluated in 33 isolated equine jejunal segments. Fifteen segments were distended with Tyrode's solution for 1 hour and nine segments for 4 hours. Tyrode's solution was added as needed to maintain the prescribed pressures. Nine other segments were left undisturbed for 4 hours after the initial distention period. On decompression of the intestinal segments, progressive peristaltic contractions resumed in all segments. Evaluation of intestinal sections by light microscopy and transmission electron microscopy showed edema of the villi and submucosa and separation of the epithelial cells adjacent to the basement membrane in all segments. The epithelial cell necrosis found in ischemic intestine was not seen. This study indicates that the necrosis found at the villous tips in distended sections of small intestine remote from the site of obstruction cannot be reproduced by IHP increases of 4 hours duration.  相似文献   
67.
The recombinant DNA technology or DNA cloning permits the isolation, amplification, and precise manipulation of specific DNA fragments. This is generally accomplished by linking or recombining the desired DNA fragment with a DNA molecule, termed the vector, which is capable of directing the replication of itself in a suitable host cell and any DNA segment covalently attached to it. Using this and associated technologies, it is possible to produce large amounts of specific proteins and to modify cell types by introducing the genes for proteins that are otherwise absent. Moreover, it is now possible to construct variants of naturally-occurring proteins with improved biological or physical properties.  相似文献   
68.
Regional perfusion of carpal tissues by forced intramedullary administration of fluids was evaluated in 10 horses. Results of subtraction radiography after perfusion with a contrast medium demonstrated that perfusate was delivered to the carpal tissues by the venous system. Perfused India ink was distributed uniformly in the antebrachiocarpal and middle carpal synovial membranes. Histologically, the ink was within the venules of the synovial villi. Immediately after perfusion with gentamicin sulfate (1 g), the gentamicin concentrations in the synovial fluid and synovial membrane of the antebrachiocarpal joint were 349 +/- 240 micrograms/mL and 358 +/- 264 micrograms/g, respectively. When gentamicin concentrations in the synovial fluid of the antebrachiocarpal joint and serum were measured 0, 0.5, 1, 4, 8, 12, and 24 hours after carpal perfusion, the mean peak gentamicin concentration in the synovial fluid was 589 +/- 429 micrograms/mL. At hour 24, the mean gentamicin concentration in the synovial fluid was 4.8 +/- 2.0 micrograms/mL. The resulting peak gentamicin concentration in the serum was 23.7 +/- 14.5 micrograms/mL immediately after the perfusion; it decreased below the desired trough level of 1 micrograms/mL between hours 4 and 8.  相似文献   
69.
Abstract— Local scarification and infection with orf virus induced an influx into the dermis of a significantly greater number of T cells than scarification alone. These cells accumulated underneath the early lesion caused by the scarification and later within epidermal pustules which formed as a result of infection. Cells of the γδ, T4 and T8 subsets were all implicated in this response. Dermal B cell numbers also rose in response to infection but relatively fewer B cells were found within pustules. Dendritic cells reactive for IgM were prominent under the initial lesion caused by scarification and dense aggregations occurred under the degenerating epidermis about 72 h after infection. Résumé— L'infection par scarification locale de virus de l'ecthyma contagieux du mouton a provoqué un influx de lymphocytes T dans le derme significativement plus important que lors de scarification seule. Ces cellules s'accumulaient sous les lésions précoces provoquées par la scarification et plus tard au niveau des pustules resultant de l'infection. Les lymphocytes T3, T4 et γδ, étaient impliqués dans cette reaction. Le nombre de lymphocytes B dermiques augmentait aussi en réponse à l'infection, mais peu d'entre eux étaient retrouvér dans les pustules. Les cellules répondant à l'lgM étaient majoritaires sous les seules lésions provoquées par scarification et des agrégations denses apparaissaient sous l'épiderme dégénéré 72 heures aprés l'infection. Zusammenfassung— Die lokale Skarifikation und Infektion mit dem Orf-Virus führte zum Einwandern von einer signifikant größeren Anzahl von T-Zellen in die Dermis, als die Skarifikation allein. Die Zellen akkumulierten sich unter der frühen Skarifikationsläsion und später innerhalb der epidermalen Pusteln, die sich durch die Infektion ergaben. Zellen der Gamma-delta-, T4-und T8-SubpopuIationen waren an dieser Reaktion beteiligt. Auch die Anzahl dermaler B-Zellen stieg als Antwort auf die Infektion, aber innerhalb der Pusteln wurden, relativ gesehen, weniger B-Zellen gefunden. Die auf IgM reaktiven Denritenzellen hoben sich unter der initialen Läsion durch die Skarifikation hervor, dichte Aggregationen fanden sich unter der degenerierenden Epidermis ungefähr 72 Stunden nach der Infektion. Resumen Infección e introducción por medio de multiples punturas cutáneas del virus Orf, produjo un mayor aflujo de linfocitos T en la dermis que punturas de manera aislada. Éstas células se acumularon debajo de la lesión primaria causada por las punturas y de forma tardía en las pústulas epidérmicas, las cuales se formaron como resultado de la infección. Las células del tipo yó de los subgrupos T4 y T8, se encontraron todas implicadas en esta respuesta. Los números de linficitos B en la dermis se vieron aumentados como reacción a la infección, pero menos en las pústulas, relativamente. Células dentríticas reactivas a la IgM fueron prevalentes en la lesión inicial por las multiples punturas, y 72 horas despues de la infección, se detectaron agregaciones densas que ocurrieron bajo la epidermis en degeneración.  相似文献   
70.
Five configurations of pins or screws interconnected with polymethylmethacrylate (PMMA) were applied to isolated canine lumbar spines (L2 to L5) in which a complete fracture-luxation had been produced at L3 to L4. Twenty-five repaired spines and five intact control spines were subjected to four-point bending and tested once to failure in ventral flexion. The purpose of this study was to determine the effects of pin number, pin angle, and use of 3.5-mm cortical bone screws instead of smooth 3.2-mm diameter pins on rigidity and ultimate strength of spinal fractures repaired by the implant-PMMA fixation technique. Bending moment versus the angular deformation curves were recorded. Rigidity, bending moment at 10° angular deformation, moment at failure, and deformation at failure of each type of fixation were compared using analysis of variance. Spinal segments stabilized with eight pin-PMMA fixation had significantly greater rigidity and strength at failure than four pin-PMMA fixations ( P < .05). Furthermore, spinal segments stabilized with eight pins angled away from the fracture failed at significantly greater bending moment than those with eight pins angled toward the fracture ( P < .05). However, for four-pin fixation, greater strength was achieved by angling pins in the bone toward the fracture site ( P < .05). Screw-PMMA fixations failed by screw bending and were less rigid and weaker at failure than the corresponding configuration of pin-PMMA fixation ( P < .05).  相似文献   
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