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931.
Comparisons were made of Cortisol concentration and behavioural activity between piglets weaned at 3 weeks of age (early weaned piglets), and piglets weaned at 8 weeks of age (control piglets). Early weaned littermates were placed in cages with a floor area of either 0.20 m2 per piglet or 0.15 m2 per piglet. At 8 weeks of age, the piglets in the control litters were moved from the sow and early weaned piglets were moved from the cages. All litters were placed in pens, 1 pen for each litter. Radioimmunoassay was used for plasma Cortisol determination. Behavioural activity included determination of play, aggressive behaviour and non-nutritive oral activity. Statistical analysis for possible association between plasma Cortisol concentration and age, housing conditions, litter and sequence of capture of littermates for blood collection revealed a complex pattern. Generally, higher plasma Cortisol concentrations and more aggressive and non-nutritive oral activity, but less playing activity, were associated with early weaning. Plasma Cortisol concentration in individual piglets was positively correlated to both aggressive and non-nutritive oral behaviour, but was negatively correlated to playing behaviour. It is concluded that early weaning is a stressor. 相似文献
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933.
J G Vestweber D E Cole S K Quadri M K Schmidt 《Journal of the American Veterinary Medical Association》1986,189(7):804-805
A 13-month-old nonpregnant Holstein heifer had premature mammary gland development. A mesothelioma was found to involve the entire abdominal cavity, with 2 large tumorous masses adjacent to the right ovary and left kidney. Physiologic function of the ovary had been affected by the neoplasm. 相似文献
934.
The use of plant protection products requires precise forecasting of the susceptible larval stages of the grape berry moths Lobesia botrana and Eupoecilia ambiguella as these dynamics vary with the weather pattern of a particular year. The objective of this research has been to partition the relative influence of specific climatic factors on the dynamics of these insects. Data taken from 7 years of continuous monitoring of the flight occurrence of male adults, and of the following development stages (i.e. eggs and larvae), was analysed by a generalized Leslie process. The model type reduces the population to three probabilities: development, survival and fertility. Each probability can be modelled as a function of the associated weather factors, while the functional relationships and the model parameters are established. The analysis started with the simplest approach and, in a step‐by‐step procedure, model complexity was added until a sufficient fit to the overall data set was achieved. Within the magnitude of the model, development rates were controlled solely by temperature, but the duration of single stages (i.e. survival) was found to be affected by a combination of temperature and relative humidity. The model represents a combination of mechanisms within a season with empirical components. 相似文献
935.
Marcin Polonis Krzysztof Jagieo Stefan Dobosz Rafa Royski Paulina Kondraciuk Artur Gurgul Tomasz Szmatoa Konrad Ocalewicz 《Reproduction in domestic animals》2019,54(4):712-718
Ionizing radiation (IR) is applied to inactivate nuclear genome in the salmonid eggs to induce androgenetic development. However, it has been considered that doses of IR used to damage maternal chromosomes may also affect morphology of the eggs and decrease their developmental potential. Thus, the main goal of the present research was to assess alterations in the rainbow trout (Oncorhynchus mykiss) eggs caused by the high dose of IR administered during androgenesis. In the present research, rainbow trout eggs were irradiated with 350 Gy of X‐rays, inseminated and exposed to the high hydrostatic pressure (HHP) shock to develop as androgenetic doubled haploids (DHs). The distribution of lipid droplets in the irradiated and non‐irradiated rainbow trout eggs, survival rates and morphology of larvae from androgenetic and control groups were compared. It has been observed that non‐irradiated and irradiated eggs exhibited altered distribution of lipid droplets. Most of the eggs before IR treatment displayed rather equal distribution of the oil droplets. In turn, majority of eggs studied after irradiation had coalesced lipid droplets, a pattern found in eggs with reduced quality. Incidences of abnormally developed larvae were more frequently observed among fish that hatched from the irradiated eggs. Observed changes suggest X‐rays applied for the genetic inactivation of rainbow trout eggs may lead to decrease of their developmental competence. 相似文献
936.
Effect of vitamin E supplementation in milk replacer and Shiga toxoid vaccination on serum α‐tocopherol,performance, haematology and blood chemistry in male Holstein calves 下载免费PDF全文
Nadine Schmidt Tim Luhmann Liane Hüther Ulrich Meyer Stefanie A. Barth Christian Menge Jana Frahm Sven Dänicke 《Journal of animal physiology and animal nutrition》2018,102(5):1167-1180
Vitamin E (vit E), an essential antioxidant for maintaining the stability of biological membranes and the function of the immune system, is considered to support adaptive immune responses and performance in cattle. The principal virulence factor of Shiga toxin (Stx)‐producing Escherichia coli (STEC), the eponymous Stx, modulates cellular immune responses in cattle, the primary STEC reservoir. Active and passive immunization of calves with Shiga toxoids (rStxMUT) was recently shown to reduce the STEC shedding. Here, we examined the influence of vit E on calves' serum α‐tocopherol, performance, haematology, blood chemistry and its interaction with rStxMUT immunization. Data from calves having received passive (colostrum from immunized cows) and active (intramuscularly at 5th and 8th weeks of life) vaccination with rStxMUT (n = 24) were compared to unvaccinated controls (n = 24; fed with low anti‐Stx colostrum, placebo injected). For each vaccination group, data were analysed according to the level of vit E supplementation offered by milk replacer (188 IU all‐rac‐α‐tocopheryl acetate daily [VitEM] vs. 354 IU [VitEH]). An increase by 79% in daily vit E supplementation led to slightly higher serum α‐tocopherol level and earlier concentrate intake at the beginning of the experiment without significant differences in live weight gain, haematology, blood chemistry parameters and peripheral CD4+ and CD8+ T‐cell subpopulations. rStxMUT vaccination modulated the CD4+/CD8+ ratio irrespective of vit E supplementation but decreased concentrate intake in VitEH in a time‐dependent manner. Results of our study indicate that an increase in daily vit E supplementation vastly fails to exert effects on laboratory parameters and growth performance. However, observed interactive effects of vit E supply and vaccination on the regulation of feed intake deserves further attention. 相似文献
937.
Stockham SL Basel DL Schmidt DA 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1986,15(1):16-21
Nineteen dogs were identified that had mastocytemia (mast cells in venous blood samples) not associated with mast cell neoplasia. The first 10 dogs were identified by examination of blood films from dogs with suspected parvovirus enteritis (8), fibrinous pericarditis and pleuritis secondary to thoracic lacerations (1), and renal insufficiency of unknown cause (1). Because of the apparent association with acute enteritis, blood films from 52 suspected canine parvovirus cases were examined retrospectively and 8 mastocytemic dogs were found. An additional 52 canine blood films were randomly selected from the same retrospective time period and 1 mastocytemic dog was found that had pneumothorax, pelvic fractures, and hemorrhagic septic abdominal effusion secondary to renal hemorrhage and traumatized intestines. All mastocytemic dogs had acute inflammatory leukograms the day that mast cells were first detected: neutropenia with toxic neutrophils (4), neutropenia with a left shift (8), total neutrophil count within reference interval but with a left shift (5), or neutrophilia with a left shift (2). All dogs except the renal insufficiency case had circulating toxic neutrophils. Five dogs were mastocytemic on more than 1 day. The pathogenesis of the mastocytemia associated with the acute inflammatory disease was not determined. 相似文献
938.
Cytological and microbiological tests were applied to urethral and prostate secretion, initial, midstream, and postmassage urine, and ejaculate of 61 patients with granulocyte counts of approximately 2 million/ml sperm, using the working principle of four-tube testing. Findings included 8 cases of chronic urethritis (caused by Chlamydia trachomatis in 5 instances, Ureaplasma (U.) urealyticum in 2, and Mycoplasma (M.) hominis in 1), 11 cases of chronic bacterial prostatitis, most of them in concomitance with urinary tract infections, and another 11 cases of "abacterial" prostatitis caused by mycoplasma (U. urealyticum in 10 cases, M. hominis in 1). No pathogens at all were recordable from 31 patients, among these 22 without leucocyte proliferation in urethral and prostate secretion nor in urine sediments. While no positive cytological findings were recordable from controls, significant germ counts of U. urealyticum were exhibited by 4 probands. The above findings are discussed together with their problematic interpretation. 相似文献
939.
940.