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81.
Infrared thermography is a non-invasive technique which allows to distinguish between pregnant and non-pregnant animals. Detecting accurate body surface temperatures can be challenging due to external factors altering thermograph measurements. This study aimed to determine the associations between the ambient temperature, the hair coat features and the temperatures of mares' abdomens. It compared pregnant and non-pregnant mares throughout 11 months. The research was carried out on 40 Konik Polski mares, which were divided into pregnant and non-pregnant groups. The temperature (Tmax, maximal; Taver, average; Tmin, minimal) of the mares' abdomen was evaluated in two regions of interest: the whole area of the lateral surface of the mares' abdomen (Px1) and the flank area of the lateral surface of mares' abdomen (Px2). During the increasing period, the slopes in the linear regression equation did not differ significantly for ambient (Tamb) and surface temperatures in both groups. In the decreasing period, the slopes did not differ significantly for Tamb and Tmax in the non-pregnant group. They also did not differ for Tamb and Taver in Px1 and Tamb and Tmin in Px1 in both pregnant and non-pregnant groups respectively. Other slopes varied significantly (p < .001). There was no evidence of parallel changes in hair coat features and measured temperatures. The flank area appears more suitable for thermal imaging in pregnant mares due to the seasonal fluctuations in hair coat lengths.  相似文献   
82.

Background

P-wave dispersion (Pd) is a new ECG index used in human cardiology and veterinary medicine. It is defined as the difference between the maximum and the minimum P-wave duration recorded from multiple different ECG leads. So far no studies were performed assessing the importance of P-wave dispersion in dogs.

Methods

The current study was aimed at determining proper value of Pd in healthy dogs (group I), dogs with chronic valvular disease (group II) and dogs with disturbances of supraventricular conduction (group III). The tests were carried out in 53 healthy dogs, 23 dogs with chronic valvular disease and 12 dogs with disturbances of supraventricular conduction of various breeds, sexes and body weight from 1,5 to 80 kg, aged between 0,5 and 17 years, submitted to the ECG examination. ECG was acquired in dogs in a standing position with BTL SD-8 electrocardiographic device and analyzed once the recording was enlarged. P-wave duration was calculated in 9 ECG leads (I, II, III, aVR, aVL, aVF, V1, V2, V4) from 5 cardiac cycles.

Results

The proper P-wave dispersion in healthy dogs was determined at up to 24 ms. P-wave dispersion was statistically significant increased (p < 0.01) in dogs with chronic valvular disease and dogs with disturbances of supraventricular conduction. In dogs with the atrial enlargement the P-wave dispersion is also higher than in healthy dogs, although no significant correlation between the size of left atria and Pd was noticed (p = 0.1, r = 0,17).

Conclusions

The P-wave dispersion is a constant index in healthy dogs, that is why it can be used for evaluating P wave change in dogs with chronic valvular disease and in dogs with disturbances of supraventricular conduction.  相似文献   
83.
New conservation-oriented forestry aims to maintain intact populations of forest organisms by improving the conservation value of managed forests and providing protected areas. We tested the conservation value of treatments of dead wood for assemblages of early successional saproxylic beetles. In nine areas in northern Sweden, we selected one clear-cut, one mature managed forest and one reserve. In 2001-2002, we placed three blocks of spruce logs, each containing control, burned and shaded logs and a high stump (“snag”) at each site. Saproxylic beetles emerging from the dead wood were collected using emergence traps and beetles flying close to it were collected using flight-intercept traps. After one year of exposure, assemblage composition was examined, with respect to nutritionally-defined functional groups, red-listed species and fire-favoured species. Experimental snags were most complementary to control logs, supporting different assemblages of cambium consumers and fungivores and supporting more red-listed individuals. Burned logs supported depauperate assemblages, particularly with respect to cambium consumers, while shading of logs affected assemblages of fungivores, but only on clear-cuts. Despite containing less dead wood, managed forests provided valuable habitat, supporting similar assemblages of saproxylic beetles to reserves. Most functional groups were less abundant on clear-cuts than in older forests, but fire-favoured species were more common on clear-cuts, suggesting that clear-cuts may support assemblages of species associated with natural disturbances, if suitable substrates are available. Utilization of logs by saproxylic beetles changes over time, so long-term monitoring of our experimental logs will determine their lifetime conservation value.  相似文献   
84.
The purpose of this work was to define more precisely the role of Ureaplasma organisms in the aetiology of granular vulvovaginitis and balanoposthitis (GVVBP) of cattle. To contribute to this question the frequency and degree of infection with Ureaplasmas in two main groups of cattle was taken into account: (a) in cattle with symptoms of the mentioned disease, (b) in cattle without clinical symptoms. The samples of semen from 301 sires with symptoms of GVVBP and from 43 healthy sires as also vaginal mucus swabs from 96 cows with GVVBP and from 40 cows mated by the sire infected with Ureaplasma organisms and from 50 cows inseminated with semen which contained Ureaplasma organisms were taken for bacteriological examinations. The control group in relation to the above mentioned cows constituted of 22 heifers free from symptoms of GVVBP and neither inseminated nor mated naturally. It has been shown that on an average 78.1% of sires with pathological changes in the mucosa of the penis or prepuce and only 25.6% of healthy sires were infected with Ureaplasma organisms. The concentration of Ureaplasma organisms was also significantly higher in material obtained from sires with symptoms of the disease than in that from healthy animals. Ureaplasma organisms were demonstrated more frequently (72.7%) in cows with GVVBP than in cows without these symptoms (13.3%). Similarly, as in the material obtained from sires, in the material taken from cows with symptoms of the disease the concentration of Ureaplasma organisms was significantly higher than that in the material originating from the healthy cows. The obtained findings may indicate that Ureaplasma organisms play a role in the aetiology of GVVBP.  相似文献   
85.
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87.
The effect of Ferrodex, vitamin A and synthetic beta-carotene on the content of iron and copper in the blood serum has been investigated in three groups of calves: I control group without vitamin supplements, II group received only once with the first colostrum dose 1.5 million IU of vitamin A, III group received Rovimix beta carotene containing 10 per cent of the synthetic beta carotene with Mlekomix from the 21st day to the 13th week of life. Moreover half of the calves from each group received Ferrodex intramusculary. Content of iron, total iron binding capacity by serum proteins, level of indirect and direct copper as well as the content of ceruloplasmin were determined in the blood serum of calves. Moreover hematocrit and hemoglobin content in the blood were determined. The results obtained show that a triple intramuscular injection of Ferrodex caused an increase of the level of iron, copper and ceruloplasmin in the blood serum of calves. However, a single administration of vitamin A to the calves or a continuous administration of Rovimix beta-carotene decreased significantly the level of iron and ceruloplasmin copper in blood serum as well as caused a more dynamic ceruloplasmin synthesis with a simultaneous increase in its utilization.  相似文献   
88.
Starting from the 10th day after pollination, immature embryos of winter wheat var. Grana were isolated and then vernalized for 4 to 8 weeks on Murashige and Skoog nutrients containing BAP (0.5 or 2 mg/dm3), NAA (0.5 or 2 mg/dm3), or GA3 (5 or 20 mg/dm3). Vernalized seedlings were cultivated in a greenhouse and the number of days to the heading of individual plants as well as the percentage of plants capable of generative development were estimated. The lower limit of size for 50 % survival of embryos strongly depended on the phytohormone used: from 0.9 mm in control, 1.1 mm in nutrient containing BAP, 1.2 mm for NAA, up to 1.7 mm in nutrient with GA3. Exogenous GA3 was lethal for embryos younger than 18 days but induced elongation of older embryos. Embryos isolated 2.5 to 4 weeks after pollination showed minimal requirements for the length of vernalization. BAP increased the percentage of heading plants originated from the youngest embryos. GA3 improved partial vernalization, strongly increasing the percentage of heading plants, but did not change the time from the end of vernalization to heading. It has been postulated that GA3 increases number of plants capable of overcoming the threshold of induction of generative development but does not accelerate the flowering process. Hormonized plants showed no deformation of generative development. As the effectiveness of vernalization increased, the heading of plants was faster but they were shorter, forming spikes with a smaller number of spikelets and producing fever lateral shoots. The very young embryos probably have in reserve sufficient amounts of auxins and gibberellins and therefore exogenous GA3 decreases their viability or even exerts a deleterious effect. However, as the embryos' ageing, gibberellin starvation develops. This being especially pronounced during vernalization. The de novo synthesis or activation of gibberellins takes place during the second stage of vernalization. This is why exogenous hormone improves the effectiveness of partial vernalization, though it is not possible to substitute by gibberellins the vernalization requirements of immature embryos.  相似文献   
89.
Experiments were carried out with 24 pregnant cows and their calves. The cows were divided in 2 equal groups. One of these received a supplement of animal fat additional to the feed from 4 weeks a. p. to 6 weeks p. p. Apart from clinical examinations following laboratory investigations in the blood were performed: hematological parameters, cholesterol, lipids, free fatty acids, ketone bodies, protein, glucose, bilirubin, transaminases, alkaline phosphatase, Ca, Mg, P, K, Na, Cl. The addition of fat to the feed of cows influenced the energy metabolism of the cows, the body weight of the newborn ones and some hematological parameters (incl. protein) of the calves positively.  相似文献   
90.
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