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511.
There is an increasing incidence of atopic diseases (asthma, allergic rhinitis and atopic dermatitis) in humans, especially in developed countries. Although there is a genetic predisposition to the development of these diseases, the rapid rise in incidence is suspected to be caused by environmental rather than genetic factors. Neither the incidence nor the prevalence of atopic dermatitis in the general canine population has been studied. As many of the environmental factors associated with the increasing incidence of atopic dermatitis in humans are consistently found in the environment of dogs, it would seem likely that a similar increase in the incidence of this disease would be occurring also in dogs. Epidemiological studies of canine atopic dermatitis are needed to characterize the incidence and prevalence of atopic dermatitis, and to further study the factors that contribute to the development of this disease. 相似文献
512.
K R Boschert N Allison T L Allen R B Griffin 《Journal of the American Veterinary Medical Association》1988,192(6):791-792
Bacillus piliformis infection (Tyzzer's disease) was diagnosed in a 7-year-old spayed dog that had icterus, hepatosplenomegaly, and polyuria. Hematology revealed regenerative anemia, leukocytosis, lymphopenia, and thrombocytopenia. Serum chemical analyses indicated hypocalcemia, high alkaline phosphatase activity, hypoalbuminemia, and hyperglobulinemia. At necropsy, the liver was stippled with gray-white focal lesions. Microscopically, the liver lesions were necrotic and inflammatory. Warthin-Starry-stained sections revealed rod-shaped bacteria in crisscrossing patterns characteristic of B piliformis. This dog was considerably older than dogs previously reported to have Tyzzer's disease and had a concurrent systemic hyphomycosis, suggesting it had been immunocompromised. 相似文献
513.
SUMMARY The effects of induced parturition on clinical disease and mortality of cows were studied in 51 winter-calving, pasture-fed, dairy herds in south-western Victoria. Parturition was induced when most cows were between 27 and 35 weeks of pregnancy. Control groups were selected from herdmates that were not induced to calve. The incidence of retained placenta was much greater among induced cows of all ages. The proportion of cows affected by any clinical disease other than retained placenta, and the incidence of mortality were much greater after induction among cows aged over 6 years but not among cows aged 3 to 6 years. 相似文献
514.
Johannes A. D. Lambregts Sayra G. Thacker Wade L. Griffin 《Journal of the World Aquaculture Society》1993,24(1):12-22
There has been a trend toward intensification of shrimp farming in the U.S. FiCteen simulated farms were used to evaluate economies of scale and to compare three Penaeus vannclmei commercial production strategies: semi-intensive, intensive, and very-intensive. Large economies of scale were associated with each production strategy. Over the range of farm sizes considered, investment cost per hectare decreased approximately 50% and production cost decreased approximately 25%. Farms' returns were measured with Internal Rate of Return (IRR). When investment was greater than $0.75 million, the intensive strategy provided slightly better returns to the investor than semi-intensive or very-intensive strategies. At investment levels less than $0.75 million, the semi-intensive strategy provided the highest IRR. 相似文献
515.
1. Possible relationships between fatness and lipoprotein lipase activity in adipose tissue and plasma from heparinised birds were examined in 7-week-old male and female broilers. 2. Total lipoprotein lipase activity in abdominal fat was significantly correlated (r = 0.5) with fat pad weight, but there was no correlation between specific activity of the enzyme and fat pad weight. 3. Lipoprotein lipase activity in post-heparin plasma showed no correlation with either abdominal fat or total body fat content. 4. The results indicate that measurements of lipoprotein lipase activity in biopsy samples or in post-heparin plasma are of no value in predicting the fat content of live birds. 相似文献
516.
Pemphigus foliaceus in dogs: a review of 37 cases 总被引:4,自引:0,他引:4
P J Ihrke A A Stannard A A Ardans C E Griffin 《Journal of the American Veterinary Medical Association》1985,186(1):59-66
Thirty-seven dogs with pemphigus foliaceus were seen over a span of 9 years in a veterinary medical teaching hospital. Four breeds of dogs (Bearded Collie, Akita, Newfoundland, Schipperke) were at significant elevated risk when compared with both the dermatology canine case population and the hospital canine population. The mean age of onset was 4.2 years. The dorsal part of the muzzle was the most common site of initial involvement in over 50% of the dogs, and lesions of the head were seen first in 81% of the dogs. Disease progression was gradual (greater than 3 months) in 73% of the dogs. Somewhat bilaterally symmetric scaling, crusting, and alopecia were seen in all of the dogs. Vesicles, pustules, and bullae were not seen commonly, but target lesions with peripheral collarettes were seen frequently. Most dogs had characteristic footpad lesions, with erythematous swelling at the pad margins, cracking, and villous hypertrophy. Generalized exfoliative dermatitis was seen in dogs with widespread disease. Pruritus was noted in less than one half of the dogs. Typical histopathologic findings included subcorneal and intragranular cell layer epidermal pustules, or intrafollicular pustules with prominent acantholysis. Direct immunofluorescence in an intercellular pattern was noted in 76% of the dogs tested and indirect immunofluorescence was noted in 75% of a much smaller sample. Thirty-nine percent of the dogs responded to corticosteroid therapy alone, and 50% and 55% responded, respectively, to prednisone and cytotoxic drugs, and to prednisone with aurothioglucose. Aurothioglucose was successful alone in 27% of the dogs. One-year survival was achieved in 53% of the dogs. 相似文献
517.
A study on the economic effects of naturally acquired trypanosomiasis in sheep and goats over a period of 35 weeks under range conditions in the Kiboko area of Kenya indicated that the financial loss from reduced weight gain and death amounted to 36.2 and 62.9 Kenya shillings per head for goats and sheep respectively. This was derived from the weight loss through death together with the reduced weight gain of the survivors compared with treated animals. The study also compared the efficacy of 3 drug regimes in goats and suggests that although quinapyramine (prophylactic) B.vet.C. provided the longest protective period, the weight increase of the stock under isometamidium chloride treatment was higher. The benefits of the drugs used are discussed. 相似文献
518.
Debra A Schmidt Monty S Kerley Ingrid J Porton James H Porter Janet L Dempsey Mark E Griffin Mark R Ellersieck William C Sadler 《Journal of zoo and wildlife medicine》2005,36(2):204-211
Black lemurs, Eulemur macaco, are classified as generalist feeders, consuming a proportion of fruits and leaves that varies with seasonal availability. It is hypothesized that black lemurs are capable of using neutral detergent fiber (NDF) as a source of energy through fiber fermentation in the cecum and large intestine. In captivity, they are typically fed a diet of commercially available primate biscuits and readily available produce, both of which are limited in NDE Digestibility trials were conducted on 14 black lemurs; 12 were housed in groups (four, three, three, and two) and 2 were individually housed. The lemurs were fed four manufactured feeds differing in fiber form and content. A commercially available primate biscuit, containing approximately 27% NDF, served as the control diet. The second diet contained the same primate biscuits, which were ground and then incorporated into a fiber-based gel matrix. The third and fourth diets were formulated using soybean hulls or ground corncobs as the fiber source, resulting in 53% and 47% NDF, respectively. Produce was added to the diet at 36% (dry matter basis). Dry matter digestibility differed significantly among all diets. Neutral detergent fiber digestibility was highest for the ground biscuit in gel and lowest for the two high-fiber gel diets, with biscuit digestibility values falling between the two extremes. The high-fiber gel diets were successful in increasing the NDF concentrations of the primate diets; however, black lemurs were capable of only limited fiber digestion. 相似文献
519.
520.
Chiara Mattei Anna Oevermann Daniela Schweizer Julien Guevar Thomas W. Maddox Kathryn L. Fleming Emanuele Ricci Marco Rosati Roberta Biserni John F. Griffin IV Angie Rupp Rodrigo Gutierrez-Quintana Isabelle Masseau Kimberly M. Newkirk Silke Hecht Swan Specchi 《Veterinary radiology & ultrasound》2023,64(2):294-305
Intravascular lymphoma (IVL) is characterized by the proliferation of large malignant lymphocytes within the lumen of blood vessels. This retrospective, multi-center, case series study aimed to describe the MRI features of confirmed central nervous system IVL in dogs and compare them with histopathological findings. Medical record databases from seven veterinary centers were searched for cases of histologically confirmed IVL. Dogs were included if an MRI was performed. The MRI studies and histopathology samples were reviewed to compare the MRI changes with the histopathological findings. Twelve dogs met the inclusion criteria (12 brains and three spinal cords). Imaging of the brains revealed multifocal T2-weighted/FLAIR hyperintense and T1-weighted iso-hypointense lesions, with variable contrast enhancement; areas of abnormal diffusion both in arterial and venous territories in diffusion-weighted imaging; and meningeal enhancement. On gradient echo images (GRE), the changes comprised tubular susceptibility artifacts, consistent with the “susceptibility vessel sign”, and additional variably sized/shaped intraparenchymal susceptibility artifacts. Spinal cord lesions presented as fusiform T2-weighted hyperintensities with scattered susceptibility artifacts on GRE and variable parenchymal and meningeal contrast enhancement. On histopathology, subarachnoid hemorrhages and neuroparenchymal areas of edema and necrosis, with or without hemorrhage, indicating ischemic and hemorrhagic infarctions, were found. These lesions were concurrent with severely dilated meningeal and parenchymal arteries and veins plugged by neoplastic lymphocytes and fibrin. Due to the unique angiocentric distribution of IVL, ischemic and hemorrhagic infarcts of variable chronicity affecting both the arterial and venous territories associated with thrombi formation can be detected on MRI. 相似文献