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91.
Effects of watershed liming on the biomass and tissue chemistry of planted Picea rubens Sarg. (red spruce) seedlings were investigated for two growing seasons after two subcatchments in a forested Adirondack, New York (U.S.A.) watershed were limed aerially with 6.89 t ha-1 of calcitic limestone (CaCO3). Picea rubens has been the focus of numerous atmospheric deposition research studies, but less well investigated for responses to amelioration. Picea rubens seedlings were planted in limed and reference subcatchments and harvested the first and second growing season after liming to measure total, foliar, and stem (i.e., branch) biomass, and concentrations of Ca, Mg, K, Al, Na, and P in the annual growth increment of foliage and branches. In the second year after liming, both foliage and stem biomass of seedlings from reference plots were at least 50% greater than seedling biomass from limed plots. Seedlings in limed areas had significantly greater foliar concentrations of Mg and P in the first year after liming, but not in the second year. Foliar Ca was not significantly different in limed than reference seedlings. Foliar Al concentrations were greater in reference than limed seedlings, but still below documented toxicity levels. Stem concentrations of Mg, K, and P in seedlings from limed areas decreased significantly between the first and second growing season after liming, while reference seedling stem concentrations either increased or declined only slightly. Correlations among foliar nutrients and foliar biomass from limed plots were negative and suggest an inverse dilution effect. Foliar Al concentrations were negatively correlated with Ca, Mg, K, and P in seedlings from reference plots, but positively correlated in limed plots. The adverse response of P. rubens seedlings to lime may reflect changes in nutrient availability associated with changes in soil pH.  相似文献   
92.
Generalized additive models (GAMs) were used to investigate the relationships between annual recruitment of natural coho salmon (Oncorhynchus kisutch) from Oregon coastal rivers and indices of the physical ocean environment. Nine indices were examined, ranging from large‐scale ocean indicators, e.g., Pacific Decadal Oscillation (PDO), to indicators of the local ecosystem (e.g., coastal water temperature near Charleston, OR). Generalized additive models with two and three predictor variables were evaluated using a set of performance metrics aimed at quantifying model skill in short‐term (approximately 1 yr) forecasting. High explanatory power and promising forecast skill resulted when the spring/summer PDO averaged over the 4 yr prior to the return year was used to explain a low‐frequency (multi‐year) pattern in recruitment and one or two additional variables accounted for year‐to‐year deviations from the low‐frequency pattern. More variance was explained when averaging the predictions from a set of models (i.e., taking the ensemble mean) than by any single model. Making multiple forecasts from a set of models also provided a range of possible outcomes that reflected, to some degree, the uncertainty in our understanding of how salmon productivity is driven by physical ocean conditions.  相似文献   
93.
Objective— This case report describes the surgical removal of an intra‐abdominal tumor from a Mexican axolotl (Ambystoma mexicanum). The animal was admitted with left abdominal swelling that had increased over 4 months. Methods— Surgical removal was performed under general anesthesia with MS222 under an operating microscope. Exploratory laparotomy was performed through 2.5 dorsocranial skin incision in the left flank, followed by subcutaneous dissection. Results— The tumor involved the spleen, was adjacent to the descending colon, and supplied by vessels from the spleen, stomach, and colon. The mass was removed by clamping and transecting the spleen and the peritoneum was closed with a continuous suture pattern, while abdominal muscles and skin were closed in layers. After a total duration time of anesthesia of 90 minutes the animal was kept in prophylactic antibiotic baths. Tissue sections revealed characteristics of both lymphangiosarcoma and lymphosarcoma with an appearance typical for a malignant tumor. Conclusions— Abdominal surgery was performed in an axolotl and the surgical wound healed without complication.  相似文献   
94.
Dynamic nasopharyngeal collapse with upper airway obstruction is an important cause of exercise intolerance in performance horses. Its underlying pathophysiology is not fully understood. We hypothesize that head position affects pharyngeal diameter, and thus head position may be a contributing factor to nasopharyngeal obstruction. Fifteen adult healthy horses were subjected to endoscopy and radiography at rest. The pharyngeal diameter was measured at nine different head and neck positions. The effect of sedation and breathing cycle on the pharyngeal diameter was determined, and the relationship between the head angle and the pharyngeal diameter was analyzed. There was a significant influence of head and neck position on pharyngeal diameter, with head position having the major effect (P<0.001); neck position was less important, but still significant (P<0.05). The smallest pharyngeal diameter was found at the dorsal, flexed position, which is a clinically important head position in dressage horses. The largest pharyngeal diameter was found at the extended midway position. At each head level, the pharyngeal diameter decreased with flexing the head and it increased with extending the head. The head angle was not associated with pharyngeal diameter, and neither sedation status nor breathing cycle significantly affected pharyngeal diameter. A decrease in pharyngeal diameter will limit the airflow through the upper respiratory tract, and it may result in turbulence with subsequent dynamic collapse. Head and neck position should therefore be considered a possible contributing factor in horses with suspected nasopharyngeal dysfunction.  相似文献   
95.
Benign masses in the pericardium of two dogs   总被引:1,自引:0,他引:1  
Two miniature Schnauzer dogs were treated for pericardial masses. In one dog the mass consisted of necrotic fat that was attached to the apex of the pericardium by a pedicle. No obvious communication with the abdomen was present. The second dog had a peritoneopericardial hernia associated with a chronic cystic haematoma. In each case the mass was presumed to have arisen following congenital displacement of the omentum into the pericardium. The pericardial mass was removed and subtotal pericardectomy performed in both dogs. Recovery was complete in each case.  相似文献   
96.
Quantified estimates of southern rock lobster (Jasus edwardii) puerulus settlement have been undertaken in the Southern Zone fishery of South Australia since the early 1990s. An analysis of mean monthly puerulus settlement indices from 1995 to 2007 in three monitoring sites revealed a strong seasonal correlation (r > 0.94 between sites) in settlement patterns. Settlement was highest during the winter months of June, July and August with peak settlement in all sites occurring in July. A reduced secondary settlement occurred during February and March. Seasonal trends were correlated with monthly wind stress and direction data in order to investigate possible environmental drivers of settlement. Using monthly averages of wind stress, it was hypothesized that strong along‐shore wind‐stress anomalies (ASWSA) prior to peak settlement would influence puerulus indices. Maximum ASWSA over the December–May period prior to maximum settlement was therefore examined. The results showed significant correlations (P < 0.1, r = 0.51–0.90) between wind stress and puerulus settlement in all but one site. We suggest that storm events, in combination with onshore surface drift during the period of settlement, are the principal physical oceanographic mechanisms influencing settlement patterns within the Southern Zone rock lobster fishery of South Australia.  相似文献   
97.
Left-sided partial arytenoidectomy was performed in eight horses to evaluate healing. Four horses underwent conventional partial arytenoidectomy with suture apposition of the mucosa. In four horses, most of the arytenoid cartilage, including overlying mucosa, vocal fold, and laryngeal saccule, were excised en bloc without mucosal closure. The horses were monitored clinically by endoscopic examination. One horse from each group was euthanatized at weeks 2, 4, 8, and 16. Complete necropsies with gross and histologic examination of the arytenoidectomy sites were performed. Postoperative complications such as coughing, dysphagia, and aspiration pneumonia were not encountered and problems with wound healing were minimal in both groups. The defect created by partial arytenoidectomy without mucosal closure initially filled to the level of the luminal surface with granulation tissue, with a gradual transition to mature fibrous connective tissue. Grossly, the defect appeared to be healed and was completely epithelialized by week 16 without apparent narrowing of the laryngeal lumen. Partial arytenoidectomy sites with mucosal closure healed in a similar pattern by week 8. Partial dehiscence of the dorsal portion of the sutured mucosa occurred in three horses.  相似文献   
98.
Résumé— Une urtricaire due à la diethylcarbamazine associée à une dermite prurigineuse a été suspectée chez un chien mâle castré croisé Retriever. L'animal présentait des lésions d'urticaire multiples qui avaient tendance à fusionner au niveau des paupières, des lèvres, les conques auriculaires et du prépuce. Les biopsies cutanées ont révélé un infiltrat périvasculaire et périannexiel intense riche en polynucléaires éosinophiles. Parfois les polynuclaires éosinophiles étaient “dégranulés” ou présentaient des formes “en flamme”. La suppression de l'administration de diethylcarbamazine a été suivie d'une disparission rapide de toutes les lésions cutanées. L'hypothèse d'une réaction immune à la diethylcarbamazine est proposée. [Vitale, C. B., Ihrke, P. J., Gross, T. L. Putative diethylcarbamazine-induced uticaria with eosinophilic dermatitis in a dog. (Probable urticaire et dermite éosinophilique induites par la diethylcarbamazine chez un chien). Resumen— Se describe el caso de un perro macho castrado, cruzado de retriever que presentaba una dermatitis pruritica con urticaria supuestamente inducida por dietilcarbamacina. El perro mostraba multiples habones, principalmente alrededor de los ojos, la boca, los pabellones auriculares y el prepucio. El estudio histológico mostró un infiltrado perivascular y perianexal, con predominancia de eosinófilos. Ocasionalmente los eosinófilos degranulaban formando “figuras en llama”. La retirada de la terapia con dietilcarbamacina fue seguida por una mejoria rápida y espectacular de todas las lesiones cutáneas. Se postula una reacción adversa a la dietilcarbamacina mediada por factores inmunológicos. [Vitale, C. B., Ihrke, P. J. and Gross, T. L. Putative diethylcarbamazine-induced urticaria with eosinophilic dermatitis in a dog (Urticaria con dermatitis eosinofilica supuestamente inducida por dietilcarbamacina en un perro). Zusammenfassung— Es wird über eine vermutlich Diethylcarbamazin-verursachte Urtikaria mit Juckreiz bei einem männlich-kastrierten Retrievermischling berichtet. Der Hund wies generalisiert multifokale Striemen auf, die dazu tendierten um Augen, Mund, Ohrmuscheln und Präputium zusammenzulaufen. Die Hautbiopsie zeigte ein starkes perivaskuläres und periadenxales Infiltrat mit vorwiegend eosinophilen Granulozyten. Gelegentlich degranulierten die Eosinophilen zu “Flammenform”. Das Absetzen von Diethylcarbamazin führte zu einer dramatischen und raschen Abheilung aller Hautveranderungen. Es wird eine immunologischvermittelte Arzneimittelreaktion auf Diethylcarbamazin vermutet. [Putative diethylcarbamazine-induced utricaria with eosinophilic dermatitis in dogs (Vermutlich Diethylcarbamazin-verursachte Urtikaria mit eosinophiler Dermatitis beim Hund). Abstract— A suspected diethylcarbamazine-induced urticarial dermatitis with associated pruritus is reported in a castrated male mixed breed retriever. The dog had generalized multifocal wheals that tended to cluster around the eyes, mouth, pinnae, and prepuce. Skin biopsy revealed an intense perivascular and periadnexal infiltrate with eosinophils predominating. On occasion, eosinophils degranulated to form “flame figures”. Withdrawal of diethylcarbamazine resulted in dramatic and rapid resolution of all skin lesions. An immunologically mediated adverse drug reaction to diethylcarbamazine is proposed.  相似文献   
99.
The analgesic effects of fentanyl (4 μg/kg) and medetomidine (10 μg/kg) in 1 mL saline injected epidurally were measured in 15 cats. The response to an electrical cutaneous stimulus from a constant current generator was used as the index of analgesia. The stimulus was applied to a forelimb before epidural injection, and at 15, 30, 60, 90, 120, 180, 240, and 300 minutes post-injection (PI). The hindlimb was tested 5 minutes later. One mL saline only was used to control for volume of injection and saline. Medetomidine significantly increased the pain threshold for the hindlimb at 20 to 245 minutes PI compared with the preinjection level. Fentanyl significantly increased the pain threshold at 20 minutes PI only compared with preinjection levels. Medetomidine significantly increased the pain threshold of the forelimb at 15 to 120 minutes PI compared with the preinjection levels. Fentanyl did not significantly increase the pain threshold of the forelimb. Administration of medetomidine produced emesis in 12 of 15 cats in an average of 6.4 minutes PI (range, 3 to 11 minutes) and mild sedation in all cats. Injection of fentanyl produced no visible side effects in any of the cats.  相似文献   
100.
In six horses, a 0.05% solution of chlorhexidine diacetate was used to lavage one tarsocrural joint; the contralateral control joint was lavaged with lactated Ringer's solution. Horses were evaluated daily for lameness. Synovial fluid samples were collected on days 1, 4, and 8 for determination of protein concentration, total and differential leukocyte counts, and mucin clot formation. After death on day 8, synovium and osteochondral samples were collected from the tarsocrural joints for examination of morphology and proteoglycan staining. Lavage with chlorhexidine solution caused lameness that was reduced but still evident at day 8. Synovial protein concentration was significantly increased by chlorhexidine lavage; the greatest increase occurred on day 1. Joint lavage increased synovial leukocyte counts on day 1, primarily by increasing polymorphonuclear (PMN) cell counts. Although total synovial leukocyte counts returned to normal by day 4, PMN cell counts remained elevated through day 8; PMN cell counts for chlorhexidine-lavaged joints were typically twice that of control joints. Chlorhexidine lavage caused synovial ulceration, inflammation, and abundant fibrin accumulation. Consistent differences in proteoglycan staining were not detected between control and chlorhexidine-lavaged joints. Joint lavage with 0.05% chlorhexidine diacetate, the lowest known bactericidal concentration, is not recommended for equine joints.  相似文献   
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