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71.
Canine inflammatory mammary carcinoma (IMC) is a rare, locally aggressive, highly metastatic tumor that is poorly responsive to treatment. The purposes of this study were to retrospectively evaluate the history, signalment, and clinical signs of dogs with IMC; compare the outcome of affected dogs treated with traditional chemotherapy with those treated with piroxicam; evaluate Cox-2 expression of IMC cells; and correlate Cox-2 expression with outcome based on treatment. Strong cyclooxygenase-2 expression was present in all tumors. Improvement in clinical condition and disease stability was achieved in all dogs treated with piroxicam, with mean and median progression-free survival of 171 and 183 days, respectively. Median survival time of 3 dogs treated with doxorubicin-based protocols was 7 days, which was significantly less than that of dogs treated with piroxicam (median, 185 days). In conclusion, piroxicam should be considered as a single agent for the treatment of dogs with inflammatory mammary carcinoma.  相似文献   
72.
In carbonate‐containing soils a reliable determination of organic C requires a method that effectively separates organic and inorganic C without altering the organic matter. This study was conducted to determine whether HCl vapor completely removes carbonates even in dolomite‐rich soils and to what extent a widely used acid‐fumigation method has to be modified for humus‐rich soils. Furthermore, it was tested whether HCl fumigation alters organic‐C content. Since C and N parameters are often analyzed simultaneously we also tested the influence of acid‐vapor treatment on N content and on δ13C of soil organic matter. We applied fumigation with 37% HCl for 8 and 32 h using 9 carbonate‐containing soil samples. Inorganic C ranged from 7 to 124 and organic C from 9 to 267 g kg–1. The maximum contents of dolomite and calcite were 940 and 640 g kg–1, respectively. A time of 8 h was enough to completely remove all carbonates. Neither the content nor the δ13C of organic C were significantly affected by fumigation. In contrast, N contents were altered by acid treatment. Based on these results and on our experience in analyzing more than 1000 soil samples, a recommended procedure for acid fumigation of carbonate‐containing soils with a wide range of organic‐ and inorganic‐C contents was derived. Samples pretreated in this way can be analyzed reliably for their organic‐C content and δ13C. Furthermore, N and inorganic‐C contents can be determined with a quality sufficient for many purposes.  相似文献   
73.
Background: Among the various metabolic disturbances occurring in calves affected by neonatal diarrhea or ruminal acidosis, acidemia constitutes an important condition requiring specific therapy. Although various attempts have been made to estimate the degree of metabolic acidosis on the basis of clinical signs alone, some doubts have been raised regarding the accuracy and predictive value of the clinical variables suggested. HYPOTHESIS: The induction of metabolic acidosis in healthy calves via the infusion of hydrochloric acid (HCl) will lead to a clinical picture similar to that seen in neonatal calves with diarrhea or ruminal acidosis. ANIMALS: The study was carried out on 15 Holstein male calves between 5 and 19 days of age. METHODS: Hyperchloremic metabolic acidosis was induced over a period of 80 minutes by an IV infusion of 4,000 mL of 0.9% NaCl solution containing 400 mM HCl. RESULTS: Acidemia occurred rapidly and increased constantly up to a maximum value, which was reached in all calves by the end of the administration and amounted to a 22.4 mM/L mean base deficit (range from 17.0 to 33.1 mM/L). Despite the relatively severe acute acid-base imbalance during the entire observation period, no calves showed any clinical signs or depressed appetite. CONCLUSIONS AND CLINICAL IMPORTANCE: Factors other than a disturbance of the acid-base balance should be considered to be primarily responsible for the clinical picture in calves affected by diarrhea or ruminal acidosis.  相似文献   
74.
Nitrogen turnover in a loess catena N-mineralization and mineral-N-contents were determined from spring 1993 to autumn 1995 on arable soils from loess (Luvisol, Calcaric Regosol, Gleyic-Calcaric Regosol and Cumulic Anthrosol) of a catchment area called “Bonartshäuser” farm near Gondelsheim in western Kraichgau (SW-Germany). The aim was to find out, whether the course of net-N-mineralization and mineral-N-content of the soil could be explained by the parameters soil temperature and soil moisture. Soil samples were incubated in polyethylene bags on site for mineralization and aliquots analyzed in the laboratory for the determination of the mineral-N-content. In 1993, 55 kg N ha—1 were immobilized and up to 170 kg N ha—1 mineralized depending on the soil type. In 1994, between 181 and 297, and in 1994, between 59 and 230 kg N ha—1 were mineralized annually. Mineral-N-contents of the different soils throughout the experimental period (n = 45) were found to correlate much better (r2 between 0.55 and 0.86) whereas net-N-mineralization (n = 44) showed coefficients of determination (r2) just between 0.08 and 0.53. Except for the Luvisol (37%) only 0 to 8% of net-N-mineralization could be explained by the combined effect of mean soil temperature and soil moisture at the beginning of the incubation using multiple linear regression analysis. Merely 1 up to 9% of mineral-N-content of the soil could be explained by the same effect. The variability and inconsistency shown by net-N-mineralization renders it inappropriate as a tool for predicting nitrogen delivery of the soil and basis for setting rules governing permissible nitrogen amounts in the soil.  相似文献   
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76.
The objective of this study was to evaluate the inclusion of increasing levels of a commercial mix of essential oils (EOs) from cashew (Anacardium occidentale) and castor bean (Ricinus communis) as an additive in diets for Nile tilapia. Thus, 240 juveniles with an initial weight of 35.06 ± 1.02 g were distributed in a completely randomized design (four treatments and six replicates) in 24 cylindrical‐tapered tanks; the fish were fed for 60 days, four times a day, diets containing increasing levels of EO (0.10, 0.15 and 0.20%) and a control diet (without the additive). After the experimental period, the animals were desensitized, and an aliquot of blood was collected for the biochemical analysis; they were subsequently euthanized for the evaluation of productive performance and fillet chemical composition. No significant differences (p > .05) were observed in the analyses of productive performance, fillet chemical composition, and triglycerides, VLDL, total proteins, urea and glucose. However, significant differences (p < .05) were observed in the analyses of total cholesterol, HDL and LDL. Inclusion above 0.15 of the additive showed an improvement in the levels of lipoprotein carriers, increasing HDL levels and decreasing LDL values, without interfering with the fish productive performance.  相似文献   
77.
To examine the extent to which heat stress during grain filling impacts on the development and yield of winter wheat (Triticum aestivum L.), a 3-year field experiment was conducted on a loess soil with high water holding capacity in the North German Plain. Thirty-two mostly European winter wheat cultivars were exposed to heat stress in a mobile foil tunnel with maximum air temperatures of 45.7, 45.4, and 47.2°C in 2015, 2016, and 2017, respectively. The 14-day post-anthesis heat stress treatment caused an average 57.3% grain yield reduction compared to a close-by non-stressed control. The proportion of green crop area after the heat stress phase varied from 7% to 98% in 2016 and from 37% to 94% in 2017. The green crop area percentage did not significantly correlate with grain yield, indicating that the delayed senescence of stay-green phenotypes offers no yield advantage under terminal heat stress. The water soluble carbohydrate (WSC) concentration of the stems at crop maturity varied between 6 and 92 g/kg dry matter, showing that the genotypes differed in their efficiency at using the stem carbohydrate reserves for grain filling under heat stress. The stem WSC concentration correlated positively with the beginning of anthesis (r = 0.704; p < .001) but negatively with the grain yield (r = −0.431; p < .05). For heat tolerance breeding, the stem reserve strategy, i. e. the rapid and full exhaustion of the temporary carbohydrate storage therefore seems more promising than the stay-green strategy.  相似文献   
78.
Poecilia velifera is a popular fish in freshwater aquarism that naturally inhabits aquatic habitats with a wide range of salinities. Nonetheless, the effects of different salinities on the reproductive success and sex ratio of the species remain unknown. Male sex characters, sex ratio and reproductive success of P. velifera were evaluated by maintaining 160 juveniles (0.078 ± 0.011 g) in four different salinities (0; 12; 24; 36 g/L), with four replicates. The only modification observed in males was the formation of a copulatory organ from the anal fin, which was used to distinguish them from females. Timing of the formation of the male copulatory organ, and the weight and total length of males when it occurred, were recorded. Twenty‐eight fish from each treatment were euthanized after 150 day to examine the gonads and confirm sex. Eight females and four males from each treatment were then kept in their respective salinity treatments for 65 days to examine the effects of salinity on reproduction. Males were kept with females in the different treatments for 15 days, at which point they were removed. Salinity was negatively correlated with male weight and length. Salinity also affected the sex ratio, with the percentages of males and females being 32.5 and 67.5%, and 27.5 and 72.5% in the salinities of 24 and 36 g of salt/L, respectively. Fifty percent of the females kept in freshwater reproduced, while there was no reproduction in the other treatments. The maintenance of P. velifera in freshwater promoted greater reproductive success and precocity, as well as larger males.  相似文献   
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