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41.
The final stages of cervical ripening and parturition resemble an inflammatory process. Although the role of cytokines in both spontaneous and experimentally induced parturitions has been described in several small laboratory animals and humans, the involvement of pro‐inflammatory and regulatory cytokines in physiologic parturition in cows has not been determined. In this study, the cytokine expression profiles were assessed in bovine cervical tissue at several stages of pregnancy and at parturition. Serial biopsy samples of the cervix were obtained from 10 cows on day 185 and day 275 of pregnancy (which was on average 5.4 days before parturition) and at parturition. Messenger RNA expression levels of interleukin (IL)‐1β, IL‐6, IL‐8, IL‐10 and tumour necrosis factor (TNF)α were determined using real‐time polymerase chain reaction and the number of neutrophils and eosinophils was estimated by Luna and Sirius Red staining. At parturition, IL‐8 expression had increased 430‐fold (p < 0.001) when compared with that of the day 185 of pregnancy, large numbers of neutrophils had invaded the cervix while eosinophils remained scarce, IL‐1β had increased eightfold (p < 0.05) and IL‐6 had not changed significantly. Additionally, IL‐10 was increased by 10‐fold (p < 0.001) and TNFα decreased by 57% (p < 0.05) when compared with that of the day 185 of pregnancy. The large increase in expression of IL‐8, enabling the influx of neutrophils, is indicative of its important role in the final stage of cervical ripening and at parturition. As previous studies have shown that neutrophils excrete matrix metalloproteinases (MMP), this might contribute to softening of the cervix. In contrast, the only slightly increased levels of IL‐1, steady concentrations of IL‐6 and decreased TNFα, the potential consequences of increased IL‐10 expression, indicate that final cervical of cows in ripening at term parturition is an inflammatory process influenced by regulatory cytokines.  相似文献   
42.
Few information is available on parameters that can be used to objectively assess the foetal health during canine pregnancy. To identify a reliable parameter for the evaluation of foetal well‐being, the effect of pre‐gestational maternal bodyweight and gestational age on foetal heart rate (FHR) and on feto‐maternal heart rate ratio (FHR/MHR) was investigated. Seventeen client‐owned pregnant bitches of different pre‐gestational maternal bodyweight were examined by serial echo colour Doppler. Only data from 11 uncomplicated pregnancies were included in the statistical analysis. The relationship between FHR, and FHR/MHR, and independent variables was analysed by polynomial regression (p ≤ .05). The FHR and the FHR/MHR significantly fitted a multiple quadratic regression for all independent variables. They both increased from 35 to 20 days before parturition and then a decreasing pattern followed. Higher values of both parameters were observed in bitches of lowest and highest bodyweight. Patterns of FHR and FHR/MHR were similar, but the ratio better describes the effect of the independent variables on the data. Thus, the highest significance of FHR/MHR compared to FHR alone encourages the application of this ratio to evaluate foetal well‐being. The equation derived by the regression analysis of FHR/MHR could be applied in clinical practice to obtain its expected values in healthy pregnancies.  相似文献   
43.
The aim of this study was to evaluate the accuracy of ultrasonographic measurement of the deep portion of diencephalo‐telencephalic vesicle (DPTV) in the prediction of delivery date in different size bitches. The effects of litter size and foetal sex ratio on the accuracy were also investigated. For this purpose, the growth curve of DPTV was derived in large size dogs (26–40 kg) and the results of the accuracy of the prediction were compared with those obtained in small (≤10 kg) and medium (11–25 kg) size dogs by the application of the equations derived from the growth curve previously described. Ultrasonographic examinations were performed once a week during the second half of pregnancy in seven large size bitches (26–40 kg body weight). A linear regression model was adopted to analyse the relationship between the DPTV mean values and the days remaining to parturition. The results of regression analysis indicated that DPTV measurement in large size dogs is significantly and linearly related to the gestational age. Ultrasonographic measurements of DPTV were also performed during pregnancy in different size bitches with unknown breeding dates. Although the results indicated a similar accuracy of the prediction of the date of parturition in the different sizes of bitches, a higher accuracy was obtained in normal and large litter size compared with small litters. Foetal sex ratio did not affect the accuracy. In conclusion, this study demonstrated that the accuracy of the prediction of parturition day obtained by ultrasonographic evaluation of DPTV growth is reliable when specific formulae for different size dogs are applied. It should be noted that although foetal sex ratio does not affect the accuracy, the prediction could be less accurate when a small litter is present.  相似文献   
44.
Objective To determine the effect of treating naturally acquired gastrointestinal nematode and paramphistome infections on milk production in dairy cattle.
Design A field trial.
Animals One thousand two hundred and thirty nine dairy cows.
Procedure Cows were either not treated or treated with 4.5 mg/kg oxfendazole, 16.6 mg/kg oxyclozanide or 4.5 mg/kg oxfendazole and 16.6 mg/kg oxyclozanide in March, May and August.
Results A significant increase in milk production, averaging 0.4 L (SE 0.2) per day, was seen when dairy cows infected with gastrointestinal nematodes and paramphistomes were treated with oxfendazole or oxfendazole and oxyclozanide in March, May and August. Cows treated with oxyclozanide alone at these times produced no more milk than untreated cows.
Faecal egg counts confirmed that oxyclozanide treatment reduced paramphistome populations and oxfendazole treatment reduced nematode populations in cows over the 7-month monitoring period.
Conclusion When dairy cows infested with gastrointestinal nematodes and paramphistomes were treated with oxfendazole alone or oxfendazole and oxyclozanide in March, May and August milk production increased.  相似文献   
45.
A 1‐year‐old female Labrador retriever was referred with a few days history of haematic‐like vulvar discharge. Physical examination, vaginal inspection and palpation did not reveal any remarkable finding. Transabdominal ultrasound showed echogenic fluid accumulation in the vagina suggesting haemato‐pyocolpos. An exploratory laparotomy was performed: a well‐delimited ectasic vagina was identified. Ovariohysterectomy and partial vaginectomy and vaginoplasty were performed to spay the bitch and to remove the ectasic vagina. Post‐operative recovery and 12‐month follow‐up were uneventful. Clinical, morphological and histological findings were consistent with a congenital abnormality of the muscular layer of the vagina complicated by haemato‐pyocolpos. The disorganization of the vaginal tunica muscularis may have acted as locus minoris resistentiae in the vaginal wall. The organ was dilated and atonic due to the gradual accumulation of physiological fluids complicated by an overgrowth of genital bacteria. This congenital disorder has to be taken into account as differential diagnosis of haemato‐pyocolpos with vaginal discharge in young bitches.  相似文献   
46.
In the case of high valuable individuals with very precious genetic material, widening the genetic pool including gametes with poor morphological characteristics, as cumulus‐denuded oocytes (CDOs), could be an option. To improve the in vitro culture of low‐competence feline CDOs, an enriched three‐dimensional (3D) system in association with competent cumulus–oocyte complexes (COCs) was developed. For this purpose, domestic cat CDOs were cultured with or without companion COCs in the 3D barium alginate microcapsules. The overall viability and the meiotic progression of feline CDOs cocultured with COCs or cultured separately in 3D or in 2D (traditional microdrops) system were compared. The 3D system was able to support viability and meiotic resumption of the feline oocytes, as well as the 2D microdrops. In 3D microcapsules, the presence of COCs resulted in a higher viability of CDOs (91.1%, < .05), than that obtained without COCs or in 2D microdrops (71.2% and 67.3%, respectively), but the percentages of meiotic resumption were similar of those of CDOs cultured separately (55.4% vs. 40.4%, p > .05). It is notable that the presence of CDOs seemed to enhance the meiotic progression of the associated COCs. In conclusion, the 3D barium alginate microcapsules are a suitable system for feline oocytes in vitro culture, but more specific enriched conditions should be developed to improve the CDOs full competence in vitro.  相似文献   
47.
During the conservation of feline semen, the freeze-thaw procedure in particular is responsible for inducing severe spermatozoal damage, which diminishes fertilizing ability. Therefore, cold-induced damage represents a limiting factor for the conservation of semen, particularly semen from felids, which are often affected by teratospermia. In this article, feline sperm characteristics are reported, with special reference to motility and morphology, which are more likely to be affected by conservation protocols; and moreover, the causes of cold-induced damages are described. Attention has been focused on methods to evaluate functional integrity of spermatozoa, and those applied to cat semen are reviewed. Among these, a rather recently developed technique involves fluorescent staining methods, and in particular chlortetracycline. The chlortetracycline assay applied to cryopreserved cat epididymal sperm shows that it is suitable to evaluate the functional status of cat sperm.  相似文献   
48.
A significant increase in milk production, averaging 164 litres per cow per lactation (a 4.8% increase), was seen after cows infected with gastrointestinal nematodes, paramphistomes and Fasciola hepatica were treated with broad-spectrum anthelmintics. Three hundred and ninety pairs of cows from eight herds with year-round calving were studied. One cow in each matched pair was given 7.5 mg/kg fenbendazole, 7.5 mg/kg levamisole hydrochloride and 15 mg/kg oxyclozanide in March, May and August of one year; the other cow in the pair received no anthelmintic. The number of nematode and trematode eggs was significantly decreased in the faeces of treated cows.  相似文献   
49.
We aimed to study the normal puerperium in the bitch. Ovariohysterectomy was performed in nine bitches, each at a different day after normal whelping; their genital tract was subject to gross anatomical examination, as well as to histological examination and electron microscopy scanning. Corpora albicans were evenly distributed in the left and right ovaries and placental sites were evenly distributed among left and right uterine horns. Placental sites were initially of dark green to grey colour, later becoming dark brown; their length and height progressively decreased. Height of the myometrium and diameter of the uterine glands progressively decreased. Trophoblast-like cells were consistently observed at the placental sites and on the surface of the interplacental areas, at all time points where hysterectomy had been performed. It is suggested that involution of the canine genital tract can last up to 3 months and is slow. Continuous (up to D84 post-partum) presence of prominent placental sites should be considered a normal feature of canine uterine post-partum involution.  相似文献   
50.
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