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71.
72.
The purpose of this study was to evaluate the tissue response to a 70% polyhydroxybutyrate and 30% hydroxyapatite composite in the form of a bone implant, placed intracortically in the distal metaphyseal of the right femur, and subcutaneous implants in cats. Samples of the composite were implanted subcutaneously in the dorsolumbar region and the distal metaphyseal region of the right femur of the animals. The study used 12 neutered adult mixed breed cats, weighing an average of 3.5kg. The cats were randomly divided into three groups: GI, GII and GIII, according to the length of the assessment period. The assessments of their subcutaneous and bone tissues were performed at 15, 30 and 45 days and at 30, 60 and 90 days, respectively. The subcutaneous and bone reactions to the composites were characterized by granulomatous inflammation with a predominance of macrophages and giant cells. The results showed that the composites triggered a chronic local inflammatory response, despite their clinical acceptance.  相似文献   
73.
The gonads and the germinative cells of 3 male hinnies were studied with light and transmission electron microscopy with the aim to observe the development of germ cells and verify the morphological modifications due to the hybridization. The hinny seminiferous epithelium presented Sertoli cells and spermatogonia with normal features and anomalous spermatocytes I. The other cells from the spermatogenic sequence were not seen. Most of the alterations began to occur in the cytes I, which presented nuclear vacuolization and deposits of amorphous material between the carioteca and the nuclear lamina, forming vesicles, or exaggerated chromatin condensation, resulting in pyknosis. In the cytoplasm vacuolization was also observed, besides organelle destruction.
The arrest of meiosis due to lock of chromosome homologies leads to germinative cell degeneration and, therefore, the spermatogenesis arrest. This fact causes a profound alteration in the seminiferous epithelium morphology in comparison with the parental species.  相似文献   
74.
75.
This is a report on the cytologic analysis of the mammary papillar discharge in a 7‐year‐old female Doberman dog with an invasive micropapillary carcinoma. Cytologic evaluation of nipple discharge is a well‐known method for the rapid diagnosis of breast cancer in women. However, there is no previous report regarding the use of this technique for assessing mammary tumors in dogs. The aim of this study was to describe the use of mammary papillar discharge cytology for diagnosing a micropapillary carcinoma in a dog. Cytologically, evaluation of the papillar discharge revealed cells arranged in clusters in a papillary pattern or in a morula‐like arrangement, suggesting the diagnosis of a micropapillary carcinoma, which was subsequently confirmed by histopathology. Thus, mammary papillar discharge cytology should be considered as an ancillary method for evaluating mammary diseases in dogs.  相似文献   
76.
The presence of anovulatory haemorrhagic follicles during the oestrous cycle of mares causes financial impacts, slowing conception and increasing the number of services per pregnancy. Non‐steroidal anti‐inflammatory drugs (NSAIDs) such as meloxicam and phenylbutazone are used in the treatment of several disorders in mares, and these drugs can impair the formation of prostaglandins (PGs) and consequently interfere with reproductive activity. This study aimed to evaluate the effects of treatment with NSAIDs on the development of pre‐ovulatory follicles in mares. In total, 11 mares were studied over three consecutive oestrous cycles, and gynaecological and ultrasound examinations were performed every 12 h. When 32‐mm‐diameter follicles were detected, 1 mg of deslorelin was administered to induce ovulation. The first cycle was used as a control, and the mares received only a dose of deslorelin. In the subsequent cycles, in addition to receiving the same dose of deslorelin, each mare was treated with NSAIDs. In the second cycle, 4.4 mg/kg of phenylbutazone was administered, and in the third cycle, 0.6 mg/kg of meloxicam was administered once a day until ovulation or the beginning of follicular haemorrhage. All of the mares ovulated between 36 and 48 h after the induction in the control cycle. In the meloxicam cycle, 10 mares (92%) did not ovulate, while in the phenylbutazone cycle, nine mares (83%) did not ovulate. In both treatments, intrafollicular hyperechoic spots indicative of haemorrhagic follicles were observed on ultrasound. Thus, our results suggested that treatment with meloxicam and phenylbutazone at therapeutic doses induced intrafollicular haemorrhage and luteinization of anovulatory follicles.  相似文献   
77.

Accurate estimation of biomass in natural vegetation sites remains a challenge. Modeling biomass growth and production in Cerrado areas is crucial to understanding the vegetation succession process, especially regarding the changes in biomass accumulation over time. Thus, our objective was to model the growth and production of woody aboveground biomass (living and total) in a cerrado stricto sensu monitored for 27 years after implementing management systems. As expected, the basal area (with a diameter taken at 30 cm from the ground level) is the most important predictor variable and showed a higher correlation with the biomass stocks and allowed accurate and consistent estimates of these accumulated stocks over time. Future estimates of biomass production, generated from growth models that estimate production as a function of parameters observed at previous ages, indicate that maximum stocks of living (25.86?±?0.15 Mg ha?1 [mean?±?standard deviation]) and total aboveground biomass (26.11?±?0.15 Mg ha?1) are expected for a period between 28 and 30 years after the implementation of the management systems, with maximum mean annual increment between 23 and 27 years. Furthermore, the systems of equations obtained simulated reductions up to 30% of biomass after the occurrence of a forest fire at 23 years. Thus, our study can be useful for the decision-making process and developing public policies and strategies for managing and conserving natural resources in the Cerrado biome.

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78.
Chlorophyll meter readings below a threshold value would indicate the necessity to supply nitrogen (N) to the crop. This study aimed to determine threshold values for chlorophyll meter (SPAD) and nitrogen (N) rate effects on SPAD leaf measurements of potato cultivars through the crop cycle. Five N rates (0, 50, 100, 200, and 300 kg ha?1) were evaluated in a randomized block design, with four repetitions. SPAD index was measured on the oldest (OL) and on the fourth leaf from the apex (FL) at 7, 14, 21, 28, 35, and 49 days after the emergence of 90% of the plants in the plots. SPAD values decreased with plant age and were influenced by N rates and leaf position. At 21 DAE, the SPAD threshold values on FL were 43.0, 44.6, 46.5, and 50.0 for ‘Agata’, ‘Monalisa’, ‘Atlantic’, and ‘Asterix’, respectively. The corresponding values were 41.9, 43.5, 49.9, and 49.9 on OL. Plant age and leaf position should be standardized for the assessment of SPAD threshold values to diagnose nitrogen status of potato cultivars.  相似文献   
79.
Bemisia tabaci is important in agriculture worldwide, mainly because it is a vector of numerous plant viruses, probably the most important of which are members of the genus Begomovirus. Dozens of begomoviruses have been reported to infect tomato plants in Brazil, although tomato severe rugose virus (ToSRV) predominates in tomato crops. ToSRV, found so far only in Brazil, is efficiently transmitted by B. tabaci MEAM1. However, no studies have assessed the occurrence of vertical and horizontal transmission of the virus in the insect, which may have epidemiological consequences affecting disease management. This study evaluated the possibility of transmission of ToSRV between whiteflies during copulation and transovarial transmission from viruliferous females of B. tabaci MEAM1 to their progeny. Transmission of ToSRV did not occur during mating between males and females of B. tabaci MEAM1. Aviruliferous males and females confined with viruliferous insects of the opposite sex were also unable to transmit the virus to tomato plants. ToSRV was detected, by PCR, in the ovaries of viruliferous females of B. tabaci MEAM1 but not in eggs, nymphs, or adults of the progeny of viruliferous females. Adult progeny of viruliferous females also did not transmit ToSRV to tomato plants. Together, the results indicate that vertical and horizontal transmission of ToSRV by B. tabaci MEAM1 is unlikely. Sustainable management of the tomato golden mosaic disease caused by ToSRV should continue to focus on using resistant varieties, managing sources of inoculum around tomato fields, and rational chemical control of the vector.  相似文献   
80.
This study aimed compare segregating populations of common bean (Phaseolus vulgaris L.) derived from intra and inter-gene pool crosses of elite lines by estimates of some genetic and phenotypic parameters. Four elite lines highly adapted to Brazilian conditions were used (ESAL 686 and BRS Radiante: Andean gene pool; BRSMG Majestoso and BRS Valente: Mesoamerican gene pool). Two intra-gene pool (“A”: ESAL 686 × BRS Radiante; “B”: BRS Valente × BRSMG Majestoso) and two inter-gene pool segregant populations (“C”: BRS Radiante × BRSMG Majestoso and “D”: ESAL 686 × BRS Valente) were obtained. The parental lines, the cultivar Pérola and fifty-five F2:3 progenies of each population were evaluated in the rainy season 2010/2011, and afterwards (F2:4) in dry season of 2011. Estimates of genetic variance ( $\hat{\sigma }_{G}^{2}$ ), heritability on a progeny mean basis ( $\hat{h}_{p}^{2}$ ), heritability realized ( $\hat{h}_{R}^{2}$ ) and gain expected from selection (GS) were obtained at joint analysis, in each population, for the traits number of days to flowering (DTF), 100 seed weight (100SW) and seed yield (SYD). It was observed that for all traits, inter-gene pool crosses (“C” and “D”) showed higher estimates of $\hat{\sigma }_{G}^{2}$ , $\hat{h}_{p}^{2}$ , $\hat{h}_{R}^{2}$ and GS than intra-gene pool crosses (“A” and “B”), which indicates more genetic variability. However, for SYD, the higher variability was associated to lower average of seed yield, showing that even utilizing adapted parents the inter-gene pool crosses are inferior to crosses between lines of the same gene pool.  相似文献   
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