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101.
为探讨复方丁氨丙磷溶液的抗热应激作用及作用机理,以黄羽肉鸡为对象,检测各处理组肉鸡生产性能,体温及血清T3、T4、胰岛素和皮质醇等内分泌激素,血清肌酸磷酸激酶、碱性磷酸酶、乳酸脱氢酶和血糖等生化指标.将45只1日龄肉鸡仔鸡随机分成3组,每组15只,分别给予生理盐水和不同剂量的复方丁氨丙磷溶液.于14日龄开始热暴露,在高温条件下继续饲养2周,并观察和检测各项指标.试验结果表明,复方丁氨丙磷溶液能明显降低热应激肉仔鸡直肠温度,显著提高T3/T4值和胰岛素含量,能极显著降低血清肌酸磷酸激酶、碱性磷酸酶和乳酸脱氢酶活性,同时提高血糖含量,而对血清皮质醇含量无显著影响.因此,复方丁氨丙磷溶液可通过调整肉仔鸡血清部分激素含量和改变血清部分生化指标来发挥其抗应激作用.  相似文献   
102.
To determine the presence, quantity and distribution of androgen (AR) and oestrogen receptors (ER) in the antler velvet (AV), samples were collected from adult and yearling pampas deer males, as well as skin from the ventrolateral abdominal area (ASK). Samples were analysed with ligand-binding assays for AR and ER activity and processed for AR and ERβ immunohistochemistry. There was more content of AR in adults than in yearling males (p = 0.02), as well as a category and type of tissue interaction (p = 0.03). There was more ER content in adults than in yearling males (p = 0.005) and in the AV than in the skin (p = 0.0001). The AR-positive score (PS) was greater in AV than in ASK in the surface stroma (p = 0.0007). In the intermediate epidermis, the AR PS was greater in adults than in yearling males (p = 0.04) and in the ASK than in the AV (p < 0.0001). There was a male category and type of tissue interaction for AR PS in the sebaceous glands (p = 0.014). The ERβ PS in the surface stroma was greater in ASK than in AV (p = 0.004) and tended to be greater in yearling than in adult males (p = 0.093). The ERβ PS in the intermediate epithelium and the sebaceous glands was greater in adults than in yearlings (p = 0.004 and p = 0.007, respectively). In conclusion, we reported for the first time the presence of AR and ER in the velvet skin of growing antlers in pampas deer males. Therefore, the velvet skin is sensitive to both androgens and oestrogens. Furthermore, the greater content of oestrogen receptors in the velvet of adult males suggests that adults are more sensitive to this hormone than yearlings, and thus, oestrogens have greater importance in velvet activity regulation in adult males.  相似文献   
103.
水牛GEP内分泌系统的不同部位经免疫组织化学方法染色后的观察表明均存在着分泌高糖素的内分泌细胞,从十二指肠后段向后,高糖素免疫反应细胞的分布出现上升的趋势,直肠处分布密度达最高峰,但盲肠处分布密度最低。在胰中,高糖素免疫反应细胞在胰岛上分布最多,切片染色镜检呈棕黑色。在胰腺上,高糖素免疫反应细胞较少,为深棕色。高糖素免疫反应细胞的形态有长颈瓶形、锥形、梭形及椭圆形等。可明显观察到内分泌细胞的分泌物随着长的细胞突起进入腺腔、肠腔及邻近细胞或细胞间隙之中。有时可见一个腺管上有多个内分泌细胞。并且见到一个内分泌细胞的分泌物同时进入腺腔和邻近细胞或细胞间隙之中。  相似文献   
104.
大豆黄酮对肉仔鸡内分泌激素与免疫机能的影响   总被引:4,自引:0,他引:4  
选用240只1日龄艾维菌肉鸡,分别随机分为四个组,对照组饲喂基础日粮,试验组在基础日粮中分别添加5 mg/kg、10 mg/kg、15 mg/kg大豆黄酮。研究结果表明:(1)日粮添加大豆黄酮对肉公鸡免疫器官重量有增加的趋势,但差异不显著(P>0.05),(2)添加大豆黄酮仅49日龄公鸡T淋巴细胞ANAE阳性率差异显著,而其余差异均不显著(P>0.05);(3)添加大豆黄酮对肉用母鸡血清尿素氮含量影响不大,而公鸡血清尿素氮水平均显著降低,(4)添加大豆黄酮对肉用公鸡血清GH、IGF-1、睾酮匀有显著影响,而对母鸡血清GH、IGF-1无显著影响。  相似文献   
105.
Abstract Skin biopsy specimens from 107 dogs with endocrine skin disorders were examined for the presence of melanin granules in the sebaceous glands or ducts (sebaceous gland melanosis). Nineteen of these cases (17.8%) had sebaceous gland melanosis. Skin biopsy specimens from 71 dogs with follicular dysplasia were similarly examined and 27 (38.0%) had sebaceous gland melanosis. Sebaceous gland melanosis alone cannot be used to differentiate histologically follicular dysplasia and endocrine skin disorders. Résumé— Des biopsies cutanées provenant de 107 chiens présentant des troubles cutanés associés à une dysendocrinie ont été examinées pour la rechereche de granules de mélanine dans les glandes sébacées ou dans leurs canaux (mélanose des glandes sébacées). Dix neuf de ces cas (17,8%) présentaient une mélanose des glandes sébacées. Des biopsies provenant de 71 chiens à dysplasic folliculaire ont été examinées de la même manière et 27 (38%) de ces cas présentaient également une mélanose des glandes sébacées. La mélanose des glandes sébacées seule ne peut être utilisée pour différencier histopathologiquement les dysplasies folliculaires des lésions cutanées associées à une dysendocrinie. [Bagladi, M.S., Scott, D.W., Miller, W.H. Sebaceous gland melanosis in dogs with endocrine skin disease or follicular dysplasia: A retrospective study (Mélanose des glandes sébacées chez des chiens présentant une dysendocrinic à expression cutanée et chez des chiens présentant une dysplasie folliculaire). Veterinary Dermatology 1996; 7 : 85–90.] Resumen Se examinó la presencia de gránules de melanina en las glándulas sebáceas (melanosis de glándulas sebáceas) en muestras de biopsia cutánea de 107 perros con desequilibrios endocrinos cutáneos. Diecinueve de estos casos (17.8%) mostraban melanosis de glándulas sebáceas. Las muestras de biopsia cutánea de 71 perros con displasia folicular se examinaron de forma similar y 27 (38.0%) mostraban melanosis de glándulas sebáccas. La melanosis de glándulas sebáceas en sí no puede utilizarse para diferenciar histológicamente entre la displasia folicular y los desequilibrios endocrinos. [Bagladi, M.S., Scott, D.W., Miller, W.H. Sebaceous gland melanosis in dogs with endocrine skin disease or follicular dysplasia: A retrospective study (Melanosis glandulas sebaceas en perros con enfermedad endocrina o dysplasia folicular: estudio retrospectivo). Veterinary Dermatology 1996; 7 : 85–90.] Zusammenfassung— Es wurden Hautbiopsien von 107 Hunden mit endokrinen Hauterkrankungen auf das Vorkommen von Melaningranula in den Talgdrüsen oder -ausführungsgängen (Talgdrüsenmelanose) untersucht. 19 dieser Fälle (17,8%) zeigten Talgdrüsenmelanose. Die Hautbiopsien von 71 Hunden mit follikulärer Dysplasie wurden auf ähnliche Weise untersucht, 27 davon (38,0%) wiesen ebenfalls Talgdrüsenmelanose auf. Talgdrüsenmelanose allein kann nicht dazu verwendet werden, um histologisch follikuläre Dysplasie und endokrine Hauterkrankungen zu unterscheiden. [Bagladi, M. S., Scott, D. W., Miller, W. H. Sebaceous gland melanosis in dogs with endocrine skin disease of follicular dysplasia: a retrospective study (Talgdrüsenmelanose bei Hunden mit endokrinen Hauterkrankungen oder follikulärer Dysplasie: eine retrospektive Studie). Veterinary Dermatology 1996; 7 : 85–90.]  相似文献   
106.
甜菜碱促蛋鸡产蛋的内分泌作用机制   总被引:5,自引:1,他引:4  
将512和300日龄罗曼蛋鸡随机分为2组,分别饲喂添加甜菜碱0、800mg/kg的2种饲粮,于试验30、80d采血和屠宰,探讨了甜菜碱保产蛋的内分泌作用机制。结果显示,日粮中添加甜菜碱30、80d,均可显著提高产蛋鸡腺垂体和血清中FSH、LH含量(P<0.05或P<0.01);显著提高血清中T3、雌二醇(E2)、孕酮(P4)的含量(P<0.05或P<0.01);显著提高下丘脑和腺垂体中cAMP含量(P<0.05或P<0.01)。日粮中添加甜菜碱80d,可显著提高产蛋鸡血清中甲状旁腺激素(PTH)含量(P<0.05或P<0.01)。日粮中添加甜菜碱对血清中T4含量无明显影响。  相似文献   
107.
Reasons for performing study: The foal requires an active hypothalamo‐pituitary‐adrenal (HPA) axis for organ maturation and post natal survival. Prenatal administration of synthetic glucocorticoids may provide an effective method for inducing fetal maturation safely in the mare. Objectives: To determine whether dexamethasone administered to late pregnant mares: 1) will induce fetal maturation and precocious delivery; 2) is safe to use and 3) to identify endocrine responses in the mare and foal. Methods: Pregnant Thoroughbred mares received either 100 mg dexamethasone i.m. (treated n = 5) or 50 ml saline i.m. (control n = 5) at 315, 316 and 317 days of gestation. Plasma progestagens, cortisol and prostaglandin F metabolite (PGFM) concentrations were measured before and after treatment. The foals were weighed, the crown‐rump length (CRL) measured and an adrenal stimulation test performed on Day 1. Results: Dexamethasone significantly (P<0.01) reduced gestation length in treated mares without apparent adverse effects. Plasma progestagens increased (P<0.05), and cortisol and PGFM (P<0.05) decreased, following dexamethasone treatment compared with control mares. Foals were clinically mature but those from dexamethasone treated mares had reduced (P<0.05) CRL, but not bodyweights, compared with controls. Their cortisol concentrations increased following exogenous adrenocorticotrophic hormone stimulation but 2 foals from dexamethasone treated mares showed evidence of adrenal suppression. Conclusions: Dexamethasone stimulates precocious fetal maturation and delivery in healthy late pregnant mares. However, fetal HPA activity may be suppressed. Potential relevance: Dexamethasone treatment could be used to improve foal viability in mares at risk of preterm delivery. The endocrine effects of such a therapy must be evaluated before clinical intervention with glucocorticoids can be recommended.  相似文献   
108.
试验主要目的是探讨促乳中草药对泌乳母鼠内分泌功能的影响.选用妊娠18d大鼠96只,分成4组,每组24只.对照组饲喂基础饲粮,试验组分别在基础饲粮的基础上添加1%中草药(分别为王不留行、黄芪、益母草).母鼠分娩后当日将每窝仔鼠一律调整为8只.在3,11,22日龄屠宰母鼠取血清测定各激素水平.结果表明,与对照组相比,分别添...  相似文献   
109.
Environmental sex reversal (ESR), whereby environmental effects (e.g. exogenous chemicals) override genetic sex determination, is a commonly used technique in aquaculture and physiology research. We performed a systematic review and meta‐analyses of the literature that compares the sperm characteristics of masculinized genotypic females to wild‐type males. We detected no mean differences between the ejaculate volume, sperm motility, duration or linearity of each type of male. We found some large mean differences in sperm concentration (= 2.541, CI = ?0.004 to 5.086), reproductive success (= ?1.400, CI = ?2.943 to 0.142), semen osmolality (= 1.850, CI = 0.622 to 3.077) and sperm velocity (= ?0.933, CI=?1.426 to ?0.441); in the case of the latter two traits, the mean effect was statistically significant. However, any significance did not stand up to a more conservative analysis. Additionally, heterogeneity was high and we found that where large differences between the sperm of sex‐reversed and wild‐type males are reported, these effects are attributable to sperm sampling methodology. Overall, we found little evidence for large systematic differences between the sperm produced by masculinized and wild‐type male fish. Thus, masculinized genotypic females may enjoy reproductive success comparable to genotypic males. This conclusion leads to two potential implications: (i) sex‐reversed fish may influence the dynamics of wild populations and (ii) aquaculture practices may use ESR to produce males with sperm quality similar to that of genotypic males. Most studies appear to have been performed in aquaculture species (i.e. Salmonidae); thus future experiments in non‐model organisms may provide important insights in to the uniformity of the effects described.  相似文献   
110.
为探讨牛磺鹅去氧胆酸(taurochenodeoxycholic acid,TCDCA)对热应激条件下AA肉鸡、海兰褐仔鸡及昆明种小白鼠的抗热应激作用,试验检测了TCDCA对热应激条件下AA肉鸡死亡率、海兰褐仔鸡体增重及对热应激小鼠采食量、饮水量、增重、血清中皮质醇和甲状腺素(T3)含量、肝脏组织中热休克蛋白70(HSP70) mRNA表达的影响。结果表明,0.1和0.2 g/kg TCDCA可显著降低热应激AA肉鸡死亡率(P<0.05);0.05、0.1和0.2 g/kg TCDCA可极显著增加热应激海兰褐仔鸡的体增重(P<0.01);0.1 g/kg TCDCA能显著提高热应激小鼠的采食量和饮水量(P<0.05),而对其体增重无显著影响(P>0.05);0.05、0.1和0.2 g/kg TCDCA可使热应激小鼠血清T3含量显著降低(P<0.05);0.1和0.2 g/kg TCDCA可使热应激小鼠血清皮质醇含量显著升高(P<0.05);0.05、0.1和0.2 g/kg TCDCA可显著抑制热应激小鼠肝脏中HSP70 mRNA的表达(P<0.05)。综上所述,TCDCA具有抗热应激作用。  相似文献   
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