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Mechanisms of anti-hantaviral activities of bovine lactoferrin (LF) and ribavirin (Rbv) were investigated. Hantavirus focus formation at 48 hr was 15% of the control in cells treated with 400 microg/ml LF for 1 hr at 37 degrees C prior to viral infection. Post infection treatment with 100 microg/ml Rbv also inhibited the focus formation to 2.5% of the control. Combined LF pre- and Rbv post-infection treatment completely inhibited focus formation. Viral glycoprotein (G2) and nucleocapsid protein (NP) syntheses were delayed in LF pretreated cells up to 24 hr post infection (hpi) but became comparable to the control by 48 hpi. Further, LF inhibited viral shedding at 24 hpi but did not inhibit shedding after 48 hpi. However, Rbv was able to inhibit synthesis of viral proteins, (+) and (-) strand RNAs also inhibited viral shedding after 24 hr. These results suggest that LF inhibits viral adsorption to cells, while Rbv inhibits viral RNA synthesis. For in vivo trials of LF and Rbv, LF pre- and Rbv post-treatment were evaluated in suckling mice infected with hantavirus, of which 7% survived. LF concentrations of 40 and 160 mg/kg administered prior to viral challenge improved survival rates to 15% and 70%, respectively for single administration and 85% and 94%, respectively, for double administration. Rbv concentrations of 25 and 50 mg/kg gave survival rates of 68% and 81%, respectively. This suggests that both LF and Rbv are efficacious in hantavirus infection in vivo.  相似文献   
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Neuronal ceroid-lipofuscinosis (NCL) is a rare group of inherited neurodegenerative lysosomal storage diseases characterized histopathologically by the abnormal accumulation of ceroid- or lipofuscin-like lipopigments in neurons and other cells throughout the body. The present article describes the clinical, pathologic, and magnetic resonance imaging (MRI) findings of the NCL in three longhaired Chihuahuas between 16 mo and 24 mo of age. Clinical signs, including visual defects and behavioral abnormalities, started between 16 mo and 18 mo of age. Cranial MRI findings in all the dogs were characterized by diffuse severe dilation of the cerebral sulci, dilated fissures of diencephalons, midbrain, and cerebellum, and lateral ventricular enlargement, suggesting atrophy of the forebrain. As the most unusual feature, diffuse meningeal thickening was observed over the entire cerebrum, which was strongly enhanced on contrast T1-weighted images. The dogs' conditions progressed until they each died subsequent to continued neurologic deterioration between 23 mo and 24 mo of age. Histopathologically, there was severe to moderate neuronal cell loss with diffuse astrogliosis throughout the brain. The remaining neuronal cells showed intracytoplasmic accumulation of pale to slightly yellow lipopigments mimicking ceroid or lipofuscin. The thickened meninges consisted of the proliferation of connective tissues with abundant collagen fibers and mild infiltration of inflammatory cells suggesting neuroimmune hyperactivity. Although the etiology of this neuroimmune hyperactivity is not currently known, MRI findings such as meningeal thickening may be a useful diagnostic marker of this variant form of canine NCL.  相似文献   
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The seroprevalence of Toxoplasma gondii was examined in adult women and domestic animals used for meat products from the Mymensingh District, Bangladesh. Cattle, goats and sheep showed a high seroprevalence (12, 32 and 40%, respectively), while the sera from all fifteen women examined in the same area were seronegative. Considering that primary infection in women during pregnancy can cause abortion and congenital defects, accidental ingestion of T. gondii infected meat products from domestic animals represents a risk factor for adult women living in the same area.  相似文献   
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Tick-borne encephalitis virus (TBEV) is a zoonotic agent causing severe encephalitis in humans. Rodent species that are potential hosts for TBEV are widely distributed in various regions in Japan. In this study, we carried out large-scale epizootiological surveys in rodents from various areas of Japan. A total of 931 rodent and insectivore sera were collected from field surveys. Rodents seropositive for TBEV were found in Shimane Prefecture in Honshu and in several areas of Hokkaido Prefecture. These results emphasize the need for further epizootiological and epidemiological research of TBEV and preventive measures for emerging tick-borne encephalitis in Japan.  相似文献   
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The relationships between growth characteristics and wood properties were investigated for a threatened species, Pericopsis mooniana, to promote the establishment of plantations of this species in the tropics. Growth characteristics (diameter and height) and stress-wave velocity (SWV) of trees were measured for 22-year-old P. mooniana trees planted in Indonesia. The trees were categorized into three groups, fast-growing, middle-growing, and slow-growing trees, to investigate the effect of growth rate on the wood properties. In addition, radial variation of anatomical characteristics and wood properties were determined. No significant correlation was found between growth characteristics and SWV. The values for the vessel diameter, cell wall thickness of wood fibers, wood fiber length, basic density, modulus of elasticity, and modulus of rupture from wood at the bark side were higher than those at the pith side. On the other hand, vessel frequency gradually decreased from pith to bark. These results suggested that low-quality wood, such as juvenile wood, existed near the pith area.  相似文献   
149.
A new disease causing necrotic streaks on stems and necrosis on leaves of aster (Callistephus chinensis) and Russell prairie gentian (Eustoma grandiflorum) was observed in Toyama Prefecture, Japan, in September 2009. On the bases of host reactions, serological reactions, viral particle morphology, and the nucleotide sequence of the nucleocapsid protein gene, the causal pathogen was identified as Chrysanthemum stem necrosis virus (CSNV). This report is the first in the world of natural infection of aster and Russell prairie gentian by CSNV. We propose the name “stem necrosis of aster and Russell prairie gentian” for these new diseases.  相似文献   
150.
Cardiac hypertrophy was observed in a 9-week-old Crl:CD(SD) rat that died unexpectedly. The animal was allocated to the control group of a toxicity study, and no abnormalities in its general conditions, body weight or food intake were observed. Necropsy revealed an increase in heart weight. Gross examination indicated cardiac enlargement with thickening of the right and left ventricular walls. Histopathological examination revealed hypertrophy of the cardiomyocytes in the right and left ventricular walls and the interventricular septum. Electron microscopic examination indicated bizarre nuclei and accumulation of an increased number of various sizes of mitochondria in the perinuclear region of the hypertrophied myocytes. Hypertrophied myocytes connected by intensely folded intercalated disks were also observed. Based on these findings, the animal was diagnosed with cardiac hypertrophy. This is the first case report of cardiac hypertrophy in this strain.  相似文献   
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