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141.
In peripartum dairy cows, insulin resistance (IR) increases to adjust the direction of energy to lactation after calving. To investigate the effect of prepartum IR on postpartum reproductive performance, the insulin tolerance test (ITT) was applied to 15 cows at 3 weeks (Pre21) and 10 days (Pre10) before the predicted calving date. Blood glucose area under the curve (AUC(glu)) within 120 min after administration of 0.05 IU/kg-BW insulin was calculated. The occurrence of first ovulation, days to first artificial insemination (AI) and first AI conception rate were recorded. Nutritional status postpartum was evaluated by blood chemical analysis. Based on AUC(glu) changes from Pre21 to Pre10, cows were classified into either the AUC-up group (AUC(glu) increase, n=5) or the AUC-down group (AUC(glu) decrease, n=10). There was no difference in the decrease in blood glucose at 30 min after insulin injection between groups, although glucose recovery from 30 to 60 min during the ITT was slow at Pre10 in the AUC-up group. The AUC-up group had a higher number of days to first AI and high glucose, total protein, globulin, γ-glutamyltransferase, triacylglycerol levels and a low albumin-globulin ratio at the 14th day postpartum. The present study infers that prepartum slow glucose recovery rather than insulin sensitivity might increase the potential for subclinical health problems postpartum and thus suppress reproductive performance. During the prepartum transition period, glucose dynamics in the ITT can be considered as a new indicator for the postpartum metabolic status and reproductive performance of dairy cows.  相似文献   
142.
Two common live feeds, the Brachionus plicatilis species complex SS-type and L-type were used to assess whether there were any differences in protein hydrolysis and digestive trypsin activity in first feeding Japanese flounder. There were no significant differences in hydrolysis activity at 2, 3 and 7 days after hatching (DAH). At 5 DAH, hydrolysis activity was significantly higher in larvae fed SS-type (p?<?0.05) at 50 kDa in 1.5- and 3-h incubation whereas L-type treatment had not completely hydrolyzed the proteins after 3 h at the same molecular weight. Larvae fed SS-type had significantly higher (p?<?0.05) trypsin activity at 3, 5, 6, 7 DAH. Contribution of live prey to trypsin fraction in larvae showed significantly higher (p?<?0.05) fraction for SS-type at 5 DAH (2.18?±?0.44%) and 6 DAH (2.04?±?0.29%) and the effect of exogenous trypsin from live prey was relatively low when compared to the total trypsin activity in larvae. This study discusses the differences in ability to digest proteins in Japanese flounder when fed different rotifer morphotypes and highlights the adaptability of this species to alternative rotifer morphotypes during its early developmental stages.  相似文献   
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Wood is generally used as the interior material in museum storage rooms. Recently, however, the effects of volatile organic compounds (VOCs) from wood on artifacts has become a topic of great concern. The VOCs from four species of wood (western red cedar, spruce, kiri, and sugi) and their effects on artifact materials (two types of metal, seven types of pigment) were investigated using a deterioration-accelerating test, gas chromatography-mass spectrometry, X-ray diffraction analysis, and X-ray photoelectron spectroscopy. The results suggested that the influences on artifact materials varied greatly with wood species, and depended on specific components such as hinokitiol or acetic acid rather than the amount of total volatile organic compounds (TVOCs). It is a very serious problem that of the four species of wood, western red cedar (rich in hinokitiol), which has been recommended as an interior material for museum storage rooms, showed the heaviest deterioration on metal samples, and only this type of wood discolored enpaku (white lead) and rokushou (malachite, verdigris). In such storage rooms, museum artifacts should be carefully monitored. When selecting an interior material for a storage room or studying methods of preventing deterioration, it is very important to consider fully the characteristics of wood VOCs, not only the amount of TVOC.Part of this paper was presented at the 24th (Tokyo, June 2002) and 25th (Kyoto, June 2003) Annual Meeting of the Japan Society for the Conservation of Cultural Property  相似文献   
146.
Eight humic acids showing different degree of humification were treated with HCI (1:1). The hydrolyzed humic acids were subjected to reductive cleavage with Na-amalgam, KOH fusion and zinc dust fusion. The yields of degradation products were determined by colorimetry gas chromatography.

The perimental results Were summarized as follows:

l. The amounts of ether-soluble substances obtained by reductive cleavage with Naamlagan ranged from 21.6% for Kuragari (A type) to 7.8% for Kisokoma B2 (Rp type). The yields of phenolic substances expressed in terms of vanillic acid content ranged from 3.0% for Kuragari (A type) to 1.8% for Kisokoma B2 (Rp type). Resorcinol. p.hydroxybenzoic acid, vanillic acid, protocatechuic acid and syringic acid were detected in the gas chromatograms of the ethe-soluble substances and their total yield comprised less than 0.6% of the Kisokoma F (Rp type).

2. The KOH fusion of humic acid yielded a larger amount of degradation products as compared to reductive cleavage. The amount of ether-soluble substances ranged from 42.7% for Kisokoma F (Rp type) to 12.6% for Sochiken 1 (A type). The yields of phenolic substances, expressed in terms of amount of protocatechuic acid, ranged from 10.6% for Kisokoma F (Rp type) to 4.6% for Inogashira (A type). Exept for syringic acid, the same compounds released after ramged from 2.1% for Sochiken 2 (B type) to 0.4% for Sochiken 1 (A type).

3. The amounts of benzene-soluble substances and hydrocarbons obtained from Goshikigahara (P type) by zinc dust fusion were 20.9% and 5.2%, respectively. The yields of the hydrocarbons tended to increase in the order; P type > Rp type ≥ B type. Perylene and 2-methylanthracene were detected in the gas chromatograms of the hydrocarbons fractions and, in the case of Goshikigahara (P type), their yields were 0.031% and 0.010%, respectively.  相似文献   
147.
Black saxaul (Haloxylon aphyllum) is a native tree species tolerant of aridity and salinity. It is planted to alleviate environmental damage due to the formation of the Aralkum desert and improve vegetation of the Aral Sea region. To investigate the environmental factors that determine seedling mortality and growth after rooting, we focused on soil properties and topographic factors in a study plot. We found that a hard clay layer that was low in hydraulic conductivity underlay accumulated sandy sediments at different depths. The soil in low seedling mortality areas was consistently sandy and low in salinity from the surface to a depth of 100 cm. In areas of high seedling mortality (75–100%), soils with a high content of silt and clay, with high salinity were detected within 100 cm depths. This suggests that accumulated sand sediment over a depth of 100 cm is required for root development. Plant height was positively correlated with depth of the hard clay layer. Significant relationships with plant height were also detected in chemical and physical properties at 80–100 cm such as electric conductivity (ECe), sodium adsorption ratio (SAR), and sand ratio. However, these properties had no significant relationship at 0–20 cm or with the relative elevation of the plot, suggesting that the subsequent growth of seedlings depends more on the sub-soil environment than on-surface conditions. The assessment of sub-soil condition is recommended to make site selection for reforestation much more reliable.  相似文献   
148.
The ostrich (Struthio camelus) is an herbivorous bird with a long and developed hindgut. In the hindgut, there is a dense and highly diverse population of anaerobic bacteria, and active fermentation produces high concentrations of short-chain fatty acids. Bacteria in the hindgut of the ostrich are considered vital for both their nutritional contribution and health benefits, such as benefits to the immune and defense system of the host. We attempted to isolate Lactobacillaceae, which might be involved in improving immune function and in inhibiting pathogens. The number of colonies from ostrich feces observed on LBS agar medium was 3.64×103 per gram of feces. Three strains of Lactobacillaceae were isolated from the feces. Nearly the entire length of the 16S ribosomal RNA gene of these isolates was sequenced, and a homology search showed high identity with L. brevis (identity=99.93%), L. coryniformis (98.39%), and L. paracasei (100.0%). These isolates may be deemed potential probiotics for the ostrich.  相似文献   
149.
Size at sexual maturity and body size composition of mud crabs Scylla spp. were examined as the basis for settling a minimum landing size as a fishing regulation in Don Sak, Bandon Bay, Gulf of Thailand, which has suffered serious mangrove habitat degradation. Mud crabs were caught using baited traps and gill nets. Hooked metal rods were also used to lever the crabs out of their burrows inside the mangroves. Two mud crab species, S. paramamosain and S. olivacea, occur in the bay; S. paramamosain is the dominant species, accounting for 87% of the samples. The size at which 50% of the S. paramamosain females reached maturity (SM50) was estimated as an external carapace width (ECW) of 112.0 mm based on the morphology of the abdomen. Allometric changes in the crushing chelae height to ECW ratio suggested that the SM50 of S. paramamosain males occurred at 106.4 mm ECW. The body size composition revealed that mainly immature mud crabs were exploited in Don Sak. To maintain a sustainable fishery for mud crabs, fishing regulations—including a minimum landing size based on the SM50 estimates—are essential, as is habitat restoration.  相似文献   
150.
Sawdusts of sugi (Cryptomeria japonica) wood prepared before and after steam drying at 120°C in a kiln were extracted with n-hexane and ethyl acetate to give n-hexane extracts and ethyl acetate extracts. From gas chromatography-mass spectrometry analysis of the ethyl acetate extracts from woods before and after steam drying, the components of 4-epi-cubebol, cubebol, and 2,7(14),10-bis-abolatrien-1-ol-4-one, which existed in the raw sugi wood, were proved to disappear in the steam-dried wood. These components were also absent in the ethyl acetate extract of the steam-condensed solution of waste steam from the kiln outlet. When these three components were treated with 0.2% (v/v) acetic acid solution at 120°C, δ-cadinene was produced as a major product from both 4-epi-cubebol and cubebol by dehydration and cleavage of the cyclopropane ring, and cryptomerone from 2,7(14),10-bisabolatrien-1-ol-4-one by hydration. The chemical changes of the three components presumably occur during steam drying of the sugi wood. This study was presented in part at the 85th Spring Meeting of the Chemical Society of Japan, Kanagawa, Japan, March 26–29, 2005  相似文献   
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