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11.
The aim of this study was to investigate, whether the activity of matrix metalloproteinase (MMP)-2 and -9 in the serum of pregnant and non-pregnant bitches differs significantly. For this purpose, 81 blood samples were taken from pregnant bitches at days 5-13, 15-21, 24-31, 34-40 and 41-50 after mating, and 51 samples from non-pregnant animals at corresponding times. Relative enzyme activity, calculated as the percentage of serum enzyme activity on enzyme activity in a control sample, was determined with a commercially available assay after activation of serum MMPs with p-aminophenylmercuric acetate (APMA). In addition, serum oestradiol (E(2)) and progesterone (P(4)) concentrations were measured with an enzymeimmunoassay (EIA). In the pregnant bitches, at days 5-13 and 15-21 after mating, the mean activity of both MMPs was significantly higher than in non-pregnant animals (28.5% vs 24.5% and 27.7% vs 22.6%; p < 0.01). Moreover, in the pregnant bitches, significant correlations were detected between the serum enzyme activity and the serum concentrations of E(2) (-0.900; p < 0.05) and P(4) (+0.667; p < 0.05).  相似文献   
12.
Sera of healthy pregnant (group I, n = 11) and non-pregnant (group II, n = 11) bitches were screened for autoantibodies (AAb). In both groups, blood samples were drawn every fifth day between days 5 and 55 after mating. Serum was analysed via indirect immunofluorescence (IIF) with the Canine ANA HEp-2 Screening Kit. In all animals, anticytoplasmic AAb were detected. Utilizing primate-heart substrate slides AAb against contractile proteins of the cytoplasm could be observed. The predominating fluorescence pattern in pregnant animals resembled above all desmin, which was proven via Western blot. The sera were then pre-incubated with tropomyosin, actin, vimentin, vinculin and keratin solutions, and assessed on HEp-2 slides and on human and canine fibroblasts as well. The latter substrate was used to verify whether the detected Ab were in fact AAb. Utilizing tropomyosin, revealed elimination of the cytoplasmic fluorescences on all three substrates. It is therefore assumed, that in sera of healthy dogs, AAb against contractile structure proteins of the cytoplasm are present regularly. The majority of pregnant bitches presented with higher end-point titres (EPT), than to be found in non-pregnant dogs. AAb against desmin played the key role in those patterns. In addition, sera were screened for thyroid specific AAb, namely thyroglobulin, thyroid peroxidase (TPO), T3 and T4, and for AAb against insulin by ELISA or Western blot (TPO). Only in two of the pregnant bitches a weak positive reaction (1:100) for T3-AAb was detected.  相似文献   
13.
A two-step semen-extending protocol was compared to a one-step protocol in its efficiency in inhibiting growth of Haemophilus somnus, Campylobacter fetus ssp. venerealis, Mycoplasma bovis , and Ureaplasma diversum in experimentally infected semen. In both protocols, the effect of an antibiotic mixture of 500 μg gentamycin, 100 μg tylosin, 300 μg lincomycin, and 600 μg spectinomycin (GTLS) was compared to a mixture of 500 IU penicillin, 500 IU streptomycin, 150 μg lincomycin, and 300 μg spectinomycin (PSLS). The one-step extending method was as effective as the two-step extending method. Both antibiotic mixtures were equally effective in controlling C. fetus . For H. somnus and U. diversum , the PSLS mixture was more effective than the GTLS mixture. It was striking that both antibiotic mixtures had no effect in decreasing the numbers of M. bovis .  相似文献   
14.
Uterine tissue from pregnant bitches was investigated by qualitative RT-PCR for the gene expression of local factors potentially important for the implantation of canine embryos. For this purpose, 10 bitches identified as being at the time of implantation or early placentation by means of ultrasonography before ovariohysterectomy (days 20–35, n = 10) provided tissues for comparison to tissue collected in a previous study and identified as early pregnant (n = 10) or non-pregnant (n = 4) by embryo flushing after ovariohysterectomy (days 10–12 after mating; Schäfer-Somi et al. 2008 ). Uterine tissue was excised from the middle of the left horn from early pregnant and non-pregnant animals, including from interplacental and placentation sites. The following genes were investigated: CD-4, -8; cyclooxygenase (COX)-1, -2; granulocyte macrophage-colony stimulating factor (GM-CSF); hepatocyte growth factor (HGF); insulin-like growth factor (IGF)-1, -2; transforming growth factor (TGF) and tumour necrosis factor (TNF)-α; interferon (IFN)-γ; interleukin (IL)-1β, -2, -4, -6, -8, -10, -12; leukaemia inhibitory factor (LIF) and leptin. Gene expression for CD-8, COX-1, TGF-β, HGF, IGF-1, IL-2, -4,-10, IFN-γ and LIF were detected in the pre-implantation uterus, and all except IL-2 and -10 were still detectable during the implantation and placentation stage. During implantation, mRNA for IGF-2 and GM-CSF were additionally detected. The dioestrous uterus differed from the pregnant uterus because of the absence of CD-8, IL-4 and IFN-γ and the expression of CD-4, TNF-α and IL-6. The results suggest that IL-4, IFN-γ, CD-8, GM-CSF and IGF-2 are regulated in a pregnancy-specific manner and that GM-CSF and IGF-2 probably have growth supporting and immune modulating functions during implantation of the canine embryo.  相似文献   
15.
The aim of the present study was to demonstrate the presence and localization of MMP-2 and -9 by means of RT-PCR and immunohistochemistry (IHC) within the canine uterus from the pre-implantation stage until mid-gestation and to determine MMP-2 and -9 activities by means of zymography. For this purpose, samples of the uterus and salpinx from bitches were obtained after ovariohysterectomy. Pre-implantation stages (5-12 days after mating, n = 11) were determined by verifying embryos after flushing the uterus. Further groups were determined as implantation (15-19 days after mating, n = 9), post-implantation (20-30 days after mating, n = 9) and placental stages (30-45 days after mating, n = 3). A non-pregnant group (17-30 days after mating, n = 4) served as control. MMP-2 and -9 positive cells were detected in all specimens from pregnant and nonpregnant bitches, however, with different distributions. MMP-2 was present in endothelium and smooth muscles of blood vessels and the myometrium of pregnant and nonpregnant bitches, additionally in the surface epithelium of the oviduct. The latter also stained positive for MMP-9. During placentation, MMP-2 was detected mainly in fetal blood vessels and trophoblastic cells. Higher MMP-2 activity was observed in the endometrium and myometrium of all pregnant groups compared with the nonpregnant group (p < 0.05). The pregnant groups did not differ significantly from each other (p > 0.05). MMP-9 was present in blood vessels, smooth muscle cells and epithelia, such as maternal surface epithelial cells, uterine crypts and glands. During placentation, the deep uterine glands and the epithelium of the glandular chambers were immunoreactive to MMP-9. Highest MMP-9 activities were reached in the endometrium of the pre-implantation group (23.2% of total MMP-9) and placental parts (33.3%).  相似文献   
16.
The aim of the present study was to assess genes expressed in maternal uterine tissue and pre‐implantation embryos which are presumably involved in maternal recognition and establishment of canine pregnancy. For this purpose, 10 pregnant bitches were ovariohysterectomized between days 10 and 12 after mating. Four non‐pregnant bitches served as controls. Early pregnancy was verified by flushing the uterine horns with PBS solution. The collected embryos (n = 60) were stored deep‐frozen (?80°C). Uterine tissue was excised, snaps frozen in liquid nitrogen and homogenized using TRI Reagent. All embryos from one litter were thawed together and also homogenized in TRI Reagent. RT‐PCR was performed to prove mRNA expression of progesterone receptor, key enzymes of the prostaglandin synthesis pathway, selected growth factors, cytokines, immune cell receptors, major histocompatibility complex (MHC) and matrix‐metalloproteinases (MMP). Only pregnant uteri revealed the presence of mRNA for interferon (IFN)‐γ, IL‐4 and CD‐8, which resembles the milieu in humans and other mammalians. Similarly, in day 10 embryos, mRNA for transforming growth factor‐β, insulin‐like growth factor‐1,‐2, hepatocyte growth factor, leukaemia inhibitor factor, tumour necrosis factor‐α, interleukin‐1β,‐6,‐8, cyclooxygenase‐2, CD4+ cells, and MMP‐2 and ‐9 were detected, but not MHC‐I or ‐II. We therefore suppose that the canine embryo, like its human counterpart, actively initiates measures to prevent attacks from the maternal immune system to prepare its own adhesion, nidation, growth and further development.  相似文献   
17.
The dynamics of zooxanthellae populations: A long-term study in the field   总被引:1,自引:0,他引:1  
Coral bleaching characterized by the expulsion of symbiotic algae (zooxanthellae) is an increasing problem worldwide. Global warming has been implicated as one cause, but the phenomenon cannot be fully comprehended without an understanding of the variability of zooxanthellae populations in field conditions. Results from a 6-year field study are presented, providing evidence of density regulation but also of large variability in the zooxanthellae population with regular episodes of very low densities. These bleaching events are likely to be part of a constant variability in zooxanthellae density caused by environmental fluctuations superimposed on a strong seasonal cycle in abundance.  相似文献   
18.
冀中南棉区棉花黄萎病发生与气象因子关系分析   总被引:8,自引:0,他引:8  
1986~1996年在石家庄河北棉花所黄、枯萎病混生病圃,对中棉所12每年8月20~25日进行黄萎病调查,并与当地6~8月每旬的平均气温、降水量、日照时数和空气相对湿度等与发生黄萎病关系进行单项和综合分析。结果表明,7月份气温27℃是发病轻重的转折点,7月中下旬的气温是影响黄萎病发病强度的主要因素,可分为高温、低湿、少雨轻病年和低温、高湿、多雨重病年,两者出现频率接近50%。经过对黄萎病指(Y)与所有因子逐步回归分析,入选因子为7月中旬湿度(X5)、6月下旬降水量(X12)、7月中旬降水量(X14)、7月下旬日照时数(X24)和6月下旬平均气温(X30),得出回归方程可试用于黄萎病发病的预测预报。  相似文献   
19.
20.
Abstract

AIM: To assess the occurrence of Cryptosporidium oocysts in faecal specimens from foals, and investigate an outbreak of neonatal cryptosporidiosis in foals revealed in the course of the study.

METHODS: Faecal specimens from foals received by a diagnostic veterinary laboratory in New Zealand between 2006 and 2007 were submitted to Massey University and tested microscopically for the presence of Cryptosporidium oocysts. The Cryptosporidium isolates in the oocyst-positive specimens were genetically identified to species level. In addition, specimen submission data from the participating laboratory for 2005–2007 were examined. In the course of the study, the identification of one Cryptosporidium-positive specimen triggered an on-farm investigation.

RESULTS: Twelve faecal specimens submitted by the participating laboratory between 2006 and 2007 were tested further, and three were positive for C. parvum. Specimen submission records indicated a total of 67 faecal specimens were tested for Cryptosporidium by the participating laboratory between 2005 and 2007; 12 (18%) were positive. The on-farm investigation on a broodmare farm revealed a high incidence of neonatal diarrhoea in foals; C. parvum was the only enteropathogen found in the faeces of 4/4 affected foals examined. The diarrhoea in all those foals was self-limiting, manifesting during the second week of life, resembling foal heat diarrhoea, and accompanied by a short but intense period of shedding oocysts.

CONCLUSIONS AND CLINICAL RELEVANCE: The fact that Cryptosporidium parasites were identified in 18% of faecal specimens from foals analysed for this agent in 2005–2007 by the participating laboratory indicated that infection with this agent in foals is not uncommon.

Collectively, the results of this and previous studies performed in New Zealand indicate C. parvum is a cause of diarrhoea in newborn foals, potentially accounting for a proportion of cases empirically diagnosed as foal heat diarrhoea. It is therefore advisable to take precautions when handling diarrhoeic foals, until this potentially zoonotic agent is ruled out in the laboratory.  相似文献   
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