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81.
Abiodun A. Adesiyun Geoff T. Fosgate Anil Persad Mervyn Campbell Ravi Seebaransingh Alva Stewart-Johnson 《Tropical animal health and production》2010,42(8):1685-1694
The preliminary study was conducted to assess the virulence of a strain of Brucella abortus (1969D) and to compare the susceptibility of water buffalo and cattle calves to infection by the intraconjunctival route.
Seven of each cattle and water buffalo (Bubalus bubalis) calves aged 3–6 months were inoculated intraconjunctivally with counts ranging from 1.5 × 107 to 1.7 × 1010 colony forming units of B. abortus. Animals were monitored over an 8-week period for clinical manifestations and serological and hematological evidence of infection.
At slaughter, eight lymph nodes from each animal were sampled for bacteriological and histopathological assessments. Lymph
nodes from three water buffalo (43%) and five cattle (71%) yielded B. abortus (P = 0.048). Parotid/prescapular lymph nodes were most sensitive in detecting B. abortus. Our data suggest that B. abortus strain 1969D may be used as challenge strain, and water buffalo appeared to have a lower susceptibility to B. abortus infection than cattle. 相似文献
82.
Yaser Hosny Elewa Mohammad Hafez Bareedy Ahmed Awad Abu Al Atta Osamu Ichii Saori Otsuka Tomonori Kanazawa Shin-Hyo Lee Yoshiharu Hashimoto Yasuhiro Kon 《Veterinary research communications》2010,34(6):557-567
Previously, the distribution of myoepithelial cells (mecs) in the salivary glands was studied by both immunohistochemistry,
and transmission electron microscopy; however, little was elucidated concerning their morphological features, especially in
goats. This study was performed to investigate the correlation between the cytoarchitecture of the mecs in goat major salivary
glands (parotid, mandibular, and sublingual glands) and the nature of the saliva secretion. The cytoarchitectural features
of the mecs were examined by scanning and transmission electron microscopy as well as immunohistochemically. The secretory
endpieces in the parotid gland are of the pure serous type, but in both the mandibular and sublingual glands they are of the
mixed type. In all studied glands, the intercalated ducts were covered by mecs which, unlike the large stellate cells that
surrounded the secretory endpieces, were spindle-shaped with few cytoplasmic processes. Interestingly, the mecs were found
to bulge on the basal surfaces of the serous acini and intercalated ducts in all glands and to be in close contact to the
seromucous tubules surface in the mandibular and sublingual glands forming a continuous network around it. In conclusion,
the differences in the degree of development of the mecs as well as the number of their cytoplasmic processes may be correlated
with the nature of the secretion and the number of the secretory granules. Thus these observations may have some relevance
in the diagnosis of atrophy and pathogenic conditions of these glands. 相似文献
83.
Raquel M. Marques António Costa-e-Silva Artur P. Águas Luzia Teixeira Paula G. Ferreira 《Veterinary research communications》2010,34(8):659-668
Rabbit Haemorrhagic Disease (RHD) is a lethal infection caused by calicivirus that kills 90% of the infected adult rabbits
within 3 days. The calicivirus replicates in the liver and causes a fulminant hepatitis. Most studies on the pathology of
RHD have been focused on the fulminant liver disease. This may not be the only mechanism in the pathogenesis of RHD: calicivirus
infection may also induce leukopenia in the infected adult rabbits. We show now by flow cytometry analysis that the calicivirus
induces an early decrease in B and T cells, in both spleen and liver. The depletion of B and T cells was associated with apoptosis
labelled by annexin V. These changes occurred in rabbits before they showed enzymatic evidence of liver damage and persisted
after liver transaminase values were very high. We conclude that depletion of lymphocytes caused by the calicivirus infection
precedes or attends liver damage. The relative contribution of this lymphocyte depletion for the pathogenesis of the fatal
calicivirus infection of rabbits remains to be investigated. 相似文献
84.
Mengistie Taye Girma Abebe Solomon Gizaw Sisay Lemma Abebe Mekoya Markos Tibbo 《Tropical animal health and production》2010,42(4):659-667
A study was conducted to evaluate growth performances of Washera sheep under smallholder production systems in the Yilmanadensa
and Quarit districts of the Amhara National Regional State, Ethiopia. Data were collected and analysed on the growth of 690
lambs owned by 110 households from October 2004 to September 2007. Weight (kilograms) of Washera lambs at birth, 1, 3, 6,
9 and 12 months of age was 2.69 ± 0.02, 7.10 ± 0.16, 12.42 ± 0.11, 16.12 ± 0.91, 20.05 ± 0.55 and 23.47 ± 0.68, respectively.
Birth weight was significantly (P < 0.05) affected by district, year of birth, parity of the dam, birth type and sex of lamb and by the interaction effect
of parity by birth type and parity by sex of lamb. Weaning weight was also affected by year of birth, type of birth and sex
of lamb. Yearling weight was affected by only year of birth and sex of birth. The average daily weight gain (ADG; grams) from
birth to 30 days, birth to 90 days, 90 to 180 days and birth to 1 year of age was 143.37 ± 13.46, 107.09 ± 2.67, 39.78 ± 9.73
and 60.13 ± 1.89, respectively. Growth rates from birth to 30 and 90 days of age were significantly (P < 0.05) affected by birth year, birth type and sex. ADG from birth to 1 year of age was affected by lamb sex and district.
The indigenous Washera sheep had faster growth rate than those sheep breeds of Ethiopia extensively studied thus far. Integrated
efforts combining improved nutrition, health and participatory community-based breeding would help the smallholder farmers
to utilise and conserve this immense sheep genetic resource of Ethiopia. 相似文献
85.
Epizootic hemorrhagic disease virus (EHDV) is a vector-borne disease of ruminants disseminated in the tropic and subtropic
zone of the world. Gazella subgutturosa subgutturosa (goitered gazelle) is native species of Anatolia. Due to risk of extinction, captured gazelles have been taken under protection
in a restricted area at Ceylanpinar state farm. In this study, the presence of EHDV was investigated serologically in 82 goitered
gazelle and 399 cattle. Seropositivity rates in goitered gazelle and cattle were detected as 2.43% and 3.50%, respectively. 相似文献
86.
Genetic and phenotypic parameter estimates for body weights and egg production in Horro chicken of Ethiopia 总被引:1,自引:0,他引:1
Nigussie Dana E. H. vander Waaij Johan A. M. van Arendonk 《Tropical animal health and production》2011,43(1):21-28
A breeding program has been established in 2008 to improve productivity of Horro chicken, an indigenous population in the
western highlands of Ethiopia. The pedigree descended from 26 sires and 260 dams. Body weights were measured every 2 weeks
from hatch to 8 weeks then every 4 weeks for the next 8 weeks. Egg production was recorded to 44 weeks of age for one generation.
Genetic parameters were estimated using animal model fitted with common environmental effects for growth traits and ignoring
common environment for egg production traits. Direct heritabilities ranged from low (0.15 ± 0.08), for body weight at 6 weeks,
to moderate (0.40 ± 0.23), for hatch weight. Heritabilities of common environmental effects on growth were high at hatch (0.39 ± 0.10)
and remained low afterwards. Age at first egg showed a very low heritability (0.06 ± 0.15). Heritabilities of egg numbers
in the first, second, third, and fourth months of laying were 0.32 (±0.13), 0.20 (±0.16), 0.56 (±0.15), and 0.25 (±0.14),
respectively. Heritabilities of cumulative of monthly records of egg numbers were from 0.24 ± 0.16 (for the first 2 months,
EP12) to 0.35 ± 0.16 (over the 6 months, EP16). Body weight at 16 weeks of age (BW16) has a strong genetic correlation with
the cumulative of monthly records: 0.92 (with EP12), 0.69 (with EP36), and 0.73 (with EP16). Besides their strong association,
BW16 and EP16 showed higher heritability, relative to their respective trait categories. These two traits seemed to have common
genes and utilizing them as selection traits would be expected to improve both egg production and growth performance of local
chicken. However, the standard errors of estimates in this study were mostly high indicating that the estimates have low precision.
Parameter estimations based on more data are needed before applying the current results in breeding programs. 相似文献
87.
Shahbazfar AA Mardjanmehr SH Arab HA Rassouli A Abdollahi M 《Tropical animal health and production》2011,43(4):843-849
Artemisinin has been used for centuries to treat malaria, intestinal tract helminthosis, diarrhea, and used as an antipyretic
and sedative agent, but the usage in veterinary medicine is a new field. Recently, it has been used successfully to control
experimental poultry coccidiosis. The present study aimed to determine the effects of different doses of artemisinin in broiler
chickens with chronic usage. Sixty birds divided into one control and four treatment groups that fed rations mixed with artemisinin
at doses of 17, 34, 68, and 136 ppm for 36 days. During the experiment, birds showed no clinical signs except anemia. In microscopic
examinations, heart, lung, and spleen had no lesion, but liver, kidney, and brain showed various lesions. Degenerative lesions
like intracytoplasmic eosinophilic inclusions were seen in both kidney and liver but fatty change was seen only in liver.
There was no relationship between severity of the liver lesions and drug dosage. Central chromatolysis, scattered neuronal
necrosis, and mild spongy changes were observed in five regions of the brain that were chosen for sectioning (motor cortex,
cerebellar nuclei, midbrain nuclei, and hindbrain nuclei at two separate levels). Severity of lesions in brain was dose-dependent,
and cerebral cortex was the most vulnerable area. Haematologic tests showed lower values for hematocrit and red blood cell
count dose-dependently. In conclusion, artemisinin is a promising drug for prevention and control of coccidiosis in broiler
chickens and its side effects are not too much serious especially at therapeutic doses. 相似文献
88.
Megersa B Biffa D Abunna F Regassa A Godfroid J Skjerve E 《Tropical animal health and production》2011,43(3):651-656
The involvement of Brucella infection in causing abortion was investigated in a breeding female subpopulation of 283 cattle, 756 camels, and 757 goats.
Serum samples were serially tested using the Rose Bengal test and complement fixation test. The study showed that anti-Brucella antibodies were prevalent in 10.6% (95% confidence interval (CI), 7.4, 14.9), 2.2% (95%CI, 1.4, 3.7), and 1.9% (95%CI, 1.1,
3.2) of cattle, camel, and goats, respectively. Abortion was more commonly reported in camels (23.4%) than cattle (13.8%)
and goats (12.4%). The results of this study suggested that Brucella infections contribute significantly to abortion in cattle (odds ratio (OR), = 4.7; 95%CI, 2.0, 10.8) and goats (OR = 6.9;
95%CI, 2.2, 21.7) but not in camels. The number of young animals produced by breeding females seems to be apparently reduced
in seropositive groups. Keeping more than two animal species at household level was found to be the risk factor for cattle
(OR = 3.1; 95%CI, 1.2, 7.9) and camel (OR = 5.3; 95%CI, 1.2–23.5) seropositivity to Brucella infection when compared to those animals from households that keep only two animal species. This may suggest a possibility
of cross species transmission of Brucella infection under such mixed herding. Wet season (OR = 4.8; 95%CI, 1.3, 18.1) was found to be associated with seropositivity
in goats, linked to a coincidence of increased deliveries in flocks with possible excretion of Brucella organisms. The study results suggest that Brucella infection is the likely cause of abortion in cattle and goats while other causes largely outweigh brucellosis as a cause
of abortion in camels in Borana, hence, contributing to reproductive loss. 相似文献
89.
Emmanuel Senyael Swai A. Kapaga F. Kivaria D. Tinuga G. Joshua P. Sanka 《Veterinary research communications》2009,33(8):927-936
Despite the widespread prevalence of infection with Peste des petits ruminants virus (PPRV) in goats and sheep industry in
Asia and sub-Saharan Africa, there have been few, if any, structured population-based studies examining the epidemiology of
this infection in Tanzania. In this study, we investigated the seroprevalence, and risk factors, of Peste des petitis ruminants(PPR)
in sheep and goat flocks from seven different geographical administration authorities (Ngorongoro, Monduli, Longido, Karatu,
Mbulu, Siha and Simanjiro) located in Northern Tanzania. Serum samples from 657 and 892 sheep and goats, respectively, corresponding
to 91 sheep/goat flocks and 43 villages were collected. Competitive enzyme linked immunosorbent assay (c-ELISA) was used to
detect the presence of antibodies in the serum against PPRV. Chi-square analysis and multivariable logistic regression model
were used to identify risk factors for PPRV seropositivity. Findings suggested that the sero-positive cases were significantly
higher in goats than in sheep (49.5% versus 39.8%; P = 0.002). The overall seroprevalence of PPRV infection in small ruminants
was 45.8%. Highest seroprevalence (42.6–88.02%) was observed in Mbulu, Siha, Longido, Ngorongoro districts, while antibodies
less than 40% to none were found in serum from Monduli, Karatu and Simanjiro, respectively. These findings confirm natural
transmission of PPRV under field condition for the first time in Tanzania. Results may be correlated with variations in the
sheep and goat husbandry practices within different geographic localities, the uncontrolled movement of animals, the levels
of natural immunity and the sharing of grazing field amongst agro and pastoralists. 相似文献
90.
Makimi Wakai Shusuke Hayashi Yuko Chiba Satoshi Koike Kyo Nagashima Yasuo Kobayashi 《Animal Science Journal》2021,92(1):e13598
The growth and morphology of rumen methanogenic archaea (15 strains of 10 species in 5 genera, including 7 strains newly isolated in the present study) and bacteria (14 species in 12 genera) were investigated using unsupplemented in vitro pure cultures and cultures supplemented with cashew nut shell liquid (CNSL) and its phenolic compound components, anti-methanogenic agents for ruminant animals. Growth of most of the methanogens tested was inhibited by CNSL and alkylphenols at different concentrations ranging from 1.56 to 12.5 μg/ml. Of the alkylphenols tested, anacardic acid exhibited the most potent growth inhibition. Three gram-negative bacterial species involved in propionate production were resistant to CNSL and alkylphenols (>50 μg/ml). All the methanogens and bacteria that were sensitive to CNSL and alkylphenols exhibited altered morphology; disruption of the cell surface was notable, possibly due to surfactant activity of the tested materials. Cells division was inhibited in some organisms, with cell elongation and unclear septum formation observed. These results indicate that CNSL and alkylphenols, particularly anacardic acid, inhibit both rumen bacteria and methanogens in a selective manner, which could help mitigate rumen methane generation. 相似文献