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91.
Long-term simulation using the distributed hydro-environmental watershed model is efficacious for assessing irrigation impacts on hydrological cycle in detail and for implementing watershed management successfully. In this article, the previously developed hydro-environmental watershed model (HEWM-1) is improved in the water exchange process caused by surface water-groundwater interaction via drainage canals and/or underdrains. The time-varying stream flow in canals is described by the complete one-dimensional shallow water equations in a newly introduced submodel, the open channel flow submodel. This submodel coordinates with the other submodels: the tank, soil moisture and groundwater flow submodels which are interlinked in a cascade manner. The improved model (HEWM-2) is applied to an agricultural watershed covering an area from an alluvial fan onto a nearly level alluvial plain, to be validated. The simulation by HEWM-2 is informative for identifying whether any drainage canal is gaining or losing water in relation to groundwater level. It could thus provide useful information for conserving a complex network of drainage canals which also functions as a passage for aquatic animals like fishes.  相似文献   
92.
The management of weeds and diseases that are caused by phytopathogenic fungi is important for preventing the loss of agricultural products. The aim of the present study was to identify phytotoxic and antiphytopathogenic agents from the Thai Alpinia galanga rhizome. Extracts of the dried rhizomes of A. galanga (Zingiberaceae) were separated and tested for phytotoxic activity against lettuce (Lactuca sativa L. cv. Great Lakes) and Italian ryegrass (Lolium multiflorum Lam. cv. Wasefudou) and for antiphytopathogenic activity against Alternaria porri, Colletotrichum gloeosporioides, Fusarium oxysporum and Phytophthora nicotianae. 1′‐Acetoxychavicol acetate ( 1 ) was identified as one of the main components, together with transp‐coumaryl acetate ( 3 ) and transp‐acetoxycinnamyl acetate ( 2 ). 1′‐Acetoxychavicol acetate ( 1 ) was solvolyzed with 2% EtOH to yield transp‐coumaryl ethyl ether ( 6 ), transp‐coumaryl acetate ( 3 ) and transp‐coumaryl alcohol ( 5 ). 1′‐Acetoxychavicol acetate ( 1 ) completely inhibited the root growth of the lettuce seedlings at 50 μg mL–1, but had a weaker inhibitory effect on the growth of Italian ryegrass. 1′‐Acetoxychavicol acetate also inhibited the growth of P. nicotianae and A. porri, with minimum inhibition concentration values of 15.6 and 31.5 μg mL–1, respectively. The plant growth‐inhibitory activity and fungal growth‐inhibitory activity of transp‐coumaryl acetate ( 3 ), transp‐coumaryl ethyl ether, transp‐coumaryl alcohol ( 5 ) and transp‐acetoxycinnamyl acetate ( 2 ) were lower than those of 1′‐acetoxychavicol acetate. A structure–activity relationship suggested that the strong phytotoxic and antiphytopathogenic activity of 1′‐acetoxychavicol acetate relied on the 1′‐acetoxyl group.  相似文献   
93.
A cholesterol-free diet containing dried powder of Jew's mellow leaves, persimmon leaves or sweet potato leaves respectively at 5% level as dietary fiber was fed to male Sprague-Dawley rats for about one month. The experiment was conducted twice except for sweet potato leaves. In the groups fed the diet mixed with powders of any of the three different dried green leaves, the hepatic cholesterol concentration significantly decreased. Such lowering was not observed in serum cholesterol concentration compared with the control (cellulose) group. A significant increase in fecal weight was observed in all the groups fed the green leaf samples. All the dried green leaves increased fecal excretion of bile acids per gram or per day compared with the control group in both experiments, but only the dried Jew's mellow leaves showed an increased excretion of neutral sterols. These results suggest that lowering of hepatic cholesterol by powdered green leaves is not necessarily due to the same factor, but to the increased fecal excretion of bile acids due to inhibited enterohepatic circulation in animals given these samples.  相似文献   
94.
The present study tested processes to manufacture fermented sauce from low-quality nori (dried and fresh fronds of Pyropia yezoensis). The nori sauce was prepared using three tanks with fresh or dried nori cultured in different conditions. In the present study enzymes were not added for the promotion of the degradation of nori, while in a previous study they were. The supernatants of culture mashes obtained from the three tanks were combined, and this low-quality nori sauce (LNS) was characterized and compared with sauces manufactured from high-quality nori, soy, and fish. The LNS showed low concentrations of total nitrogen compounds (0.20 g/100 ml) and free amino acids, and its taste showed a high sourness score as evaluated by a taste-sensing system. On the other hand, the LNS was rich in polysaccharides, which were observed to be readily degraded to lower molecular weight size sugars by heat treatment. The LNS showed little risk for heavy metal or allergen contamination. The obtained sauce product is expected to be commercially utilized as a component of low allergen-risk sauce products after blending with other seasonings without wheat or soy elements.  相似文献   
95.
Although chub mackerel (Scomber japonicus) is widely distributed all over the world, the relevance of its visual sensitivity to its ecology is not yet fully understood. We investigated spectral sensitivity in juvenile chub mackerel in the range of ultraviolet (UV) to visible light (369–652 nm) by electroretinogram (ERG) using light-emitting diodes (LEDs). Sensitivity peaked at a wavelength of approximately 482 nm in dark-adapted fish and 525 nm in light-adapted fish. A secondary sensitivity peak in the UV range at approximately 382 nm was found in both dark- and light-adapted fish. The UV sensitivity of chub mackerel may be attributable to UV transmissibility of the optical media and to the presence of a beta-band of visible light-sensitive visual pigments, and not to an alpha-band of UV visual pigments. This UV sensitivity may be useful for feeding or communication with other fishes.  相似文献   
96.
Histochemical observations on the enzymes of chicken yolk sac membrane   总被引:1,自引:1,他引:0  
In the endodermal cells of the yolk sac membrane of chicken embryos incubated for 12 to 18 d, the activity of glucose‐6‐phosphatase (G‐6‐Pase) was high, the activity of acid phosphatase (Acid Pase) was moderate, the activities of lactate dehydrogenase (LDH) and of glyceraldehyde‐3‐phosphate dehydrogenase (G‐3‐PDH) were low, and succinate dehydrogenase (SDH) and alkaline phosphatase (Alk Pase) activities were not detected. On the day before hatching, however, SDH became evident with low activity, and the activities of Acid Pase, LDH and G‐3‐PDH increased and remained higher until the day after. Five days after hatching, there were marked decreases in the activities of all the enzymes except SDH. Alk Pase was not detected at any time. The function of the yolk sac endo‐derm in the absorption of yolk is discussed in the light of these observations.  相似文献   
97.
Feline immunodeficiency virus infection in cats of Japan   总被引:27,自引:0,他引:27  
A seroepidemiologic survey for feline immunodeficiency virus (FIV) infection was conducted in Japan. Between June and December 1987, individual sera (n = 3,323) were submitted by veterinary practitioners from many parts of the country. Specimens were from 1,739 cats with clinical signs suggestive of FIV infection and from 1,584 healthy-appearing cats seen by the same practitioners. The overall FIV infection rate among cats in Japan was 960/3,323 cats (28.9%). The infection rate was more than 3 times higher in the clinically ill cats, compared with that in the healthy cats of the same cohort (43.9 vs 12.4%). Male cats were 1.5 times as likely to be infected as were females. Almost all FIV-infected cats were domestic cats (as opposed to purebred cats). Complete clinical history was available for 700 of 960 FIV-infected cats. Of these 700 FIV-infected cats, 626 (89.4%) were clinically ill, and the remainder did not have clinical signs of disease. The mean age at the time of FIV diagnosis for the 700 cats was 5.2 years, with younger mean age for males (4.9 years) than for females (5.8 years). Most of the infected cats (94.7%) were either allowed to run outdoors or had lived outdoors before being brought into homes. The mortality for FIV-infected cats during the 6 months after diagnosis was 14.7%, and the mean age at the time of death was 5.7 years. Concurrent FeLV infection was seen in 12.4% of the FIV-infected cats, but this was not much different from the historical incidence of FeLV infection in similar groups of cats not infected with FIV.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
98.
Buffer mainly consisting of 100 g of sodium bicarbonate and 30 g of magnesium oxide was added to the feed per head per day and given for 8 months to groups of 92 cows of milk fat depression. Milk fat increased from 3.06% (pre-treatment) to 3.68% at 4 months and 3.71% at 8 months post-treatment. Solids-not-fat was slightly increased by the buffers. Milk production was not affected. The number of rumen protozoa increased from 2.85 X 10(5)/ml (pre-treatment) to 9.61 X 10(5)/ml at 8 months post-treatment and the kinds of protozoa diversified. An increase of acetate and decrease of propionate were observed together with increased milk fat at 8 months post-treatment. An increase of hematocrit, lactate dehydrogenase, sodium and potassium, and a decrease of cholesterol and gamma-glutamyl transpeptidase in blood were recognized after the treatment. The incidence of disease was reduced. There was a significant correlation between increased milk fat percentage and increase in the number and the kinds of protozoa.  相似文献   
99.
From the distribution of enzymes, the alveoli of a uropygial gland may be divided into inner and outer zones ; the former being the region near the cavity, and the latter the peripheral region of the gland.

In the inner zone, there appeared strong activities of 17β‐hydroxy‐steroid dehydrogenase (17β‐OH‐SDH), 30α‐OH‐SDH, glucose‐6‐phosphate dehydrogenase (G‐6‐PDH), lactate dehydrogenase (LDH), NAD‐dependent malate dehydrogenase (MDH) and acid phosphatase (Acid Pase) weak activities of succinate dehydrogenase (SuDH), NADP‐dependent MDH, monoamine oxidase (MAO) and non‐specific esterase (Etase), but no activity of β‐hydroxybutyrate dehydrogenase (β‐HbDH).

In the outer zone, there appeared strong activities of LDH and MDH (NAD), moderate activities of 17β‐OH‐SDH, 3α‐OH‐SDH, G‐6‐PDH and β‐HbDH, weak activities of SuDH, MDH (NADP) and MAO, but no activities of Etase and Acid Pase.

The results were negative concerning ?5‐3β‐OH‐SDH, glutamate dehydrogenase, a‐glycerophosphate dehydrogenase, phosphorylase and alkaline phosphatase in both zones. From these results, it was concluded that there must be functional differences between the zones, and that only a part of the metabolic pathways of steroids is being performed.  相似文献   

100.
The present study was designed to determine the effects of physiological stress on milk-somatic cell counts (SCC) and function of bovine peripheral blood leukocytes (PBL). Nine healthy lactating cows were used in the examination. Five cows were transported 100 km for 4 hr (transported group; TG), and 4 cows were penned (non-transported group; NTG). Blood and milk samples were collected at 0, 2, and 4 hr after loading, and at 2 hr, and 1, 2, 3, and 6 days after unloading. The following activities were measured: adhesion receptor (CD 18 and L-selectin) expression of neutrophils and monocytes, migration capacity and percentage of apoptotic cells of neutrophils, serum soluble L-selectin (sL-selectin), plasma cortisol, and SCC. A significant increase in plasma cortisol and milk SCC was observed in TG. Leukocytosis, derived from neutrophils was recorded in TG, and was indicated by apoptotic measurement as an increase of young cells from the marginal pool. Increased migration and decreased surface expression of both L-selectin and CD 18 in neutrophils were observed after transportation. Elevated serum sL-selectin was also noted as a result of transportation. The present study indicated that transport stress modulates peripheral blood neutrophil function, particularly enhancing migration capacity, and causes diapedesis across the mammary epithelium. Increased milk SCC in transported cattle might be due to these phenomena, and severe physiological stress may bring about an increase in SCC in milk.  相似文献   
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