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51.
Intergeneric hybrids involving a wild crucifer, Diplotaxis siifolia (2n = 20; DsDs), and two crop Brassica species, namely Brassica rapa (2n = 20; AA) and B. juncea (2n = 36; AABB), were developed through sequential ovary/ovule culture. Hybridization was successful only when D. siifolia was used as the female parent, indicating unilateral cross incompatibility. Hybrids were intermediate between the parents for morphological characteristics but had low male as well as female fertility. Meiotic studies of hybrids revealed partial homoeology between Ds and A/B genomes.  相似文献   
52.
53.
A. SÜSS  B. GRAMPP 《Weed Research》1973,13(3):254-266
Zusammenfassung. Um den Einfluß verschiedener Bodenmischungen auf die Aufnahme von adsorbiertem [14C]-markíertem Monolinuron zu verfolgen, wurden jeweils 30, 45, 60, 73 und 90 g Monolinuron-behandelter Boden (0,42-0,53 μg Monolinuron/g Boden) mit unbehandeltem auf 100 g aufgefüllt und damit 15.4–67.1 μg adsorbiertes Monolinuron eingesetzt. Die Aufnahme durch Senipflanzen wurde in Neubauerversuchen während 24 Tagen verfolgt. In 3 Anbauperioden wurden 1.17–9.74 μg aufgenommen. Der überwiegende Teil blieb jedoch an den Boden adsorbiert. Bei einer Bilanzerstellung konnten 99% der zu Versuchsbeginn eingesetzten Monolinuronmenge wieder gefunden werden, Durch den Sorptionsprozeß wurde Monolinuron chemisch nicht vcerändert. Ebenso kann das Ausgangsmolekül in der Pflanze nachgewiesen werden. Die nachweisbare Monolinuronmenge in der Pflanzensubstariz wird umso geringer, je weiter die Aufnahmeintensität zurürkgeht. Über eine Isotopen-Austauschreaktion wurde versucht, das pflanzenverfügbare Monolinuron zu messen.
The uptake of adsorbed monolinuron in the soil by mustard plants  相似文献   
54.
Ultraviolet laser microprobe analyses of a calcium-aluminum-rich inclusion (CAI) from the Allende meteorite suggest that a line with a slope of exactly 1.00 on a plot of delta17O against delta18O represents the primitive oxygen isotope reservoir of the early solar nebula. Most meteorites are enriched in 17O and 18O relative to this line, and their oxygen isotope ratios can be explained by mass fractionation or isotope exchange initiating from the primitive reservoir. These data establish a link between the oxygen isotopic composition of the abundant ordinary chondrites and the primitive 16O-rich component of CAIs.  相似文献   
55.
A prevalence study was contemplated to determine the prevalence of Cryptosporidium spp. in dairy farms in Punjab, India. The cryptosporidium oocysts were detected from 50 and 25.68% from 80 diarrheic and 74 non-diarrheic animals, respectively. Both shedding and intensity of shedding were significant in calves with diarrhea. The Cryptosporidium spp. appears to be common in dairy calves and an important contributor of calf diarrhea in the Punjab province. The prevalence of the infection peaked in young calves between 0 and 30 days in both the diarrheic and non-diarrheic groups (86.4 and 66.6%, respectively). The percentage distribution of positive samples, with reference to age groups of diarrheic and non-diarrheic animals was negatively correlated with increase in age. High mortality rate and case fatality rate of 35.2 and 44.4% were observed in young calves between 0 and 30 days of age.  相似文献   
56.
Extract

Lytic lesions with microscopic features similar to those of vaccine-site sarcomas were diagnosed in the distal femur of two young neutered male cats, one a 20-month-old Birman and the other an 18-month-old domestic short-hair (DSH). Radiographically, there was extensive destruction of trabecular and cortical bone in the metaphysis and/or epiphysis of the distal femur. The DSH cat also had angular deformity of the distal femur due to asymmetrical involvement of the physis. Histologically, the lesions in both cats consisted of dense, interwoven bundles of fibrous connective tissue, amongst which there were variable numbers of plump malignant mesenchymal cells, often with very large, hyperchromatic nuclei and irregularly shaped nucleoli. Several focal aggregates of small lymphocytes were present in both tumours. Although neither cat had apparently been vaccinated in the hindlimb it is possible that the tumours had been triggered by injection of some other irritant material.  相似文献   
57.
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   
58.
Non‐genetic factors influencing functional longevity and the heritability of the trait were estimated in South African Holsteins using a piecewise Weibull proportional hazards model. Data consisted of records of 161,222 of daughters of 2,051 sires calving between 1995 and 2013. The reference model included fixed time‐independent age at first calving and time‐dependent interactions involving lactation number, region, season and age of calving, within‐herd class of milk production, fat and protein content, class of annual variation in herd size and the random herd–year effect. Random sire and maternal grandsire effects were added to the model to estimate genetic parameters. The within‐lactation Weibull baseline hazards were assumed to change at 0, 270, 380 days and at drying date. Within‐herd milk production class had the largest contribution to the relative risk of culling. Relative culling risk increased with lower protein and fat per cent production classes and late age at first calving. Cows in large shrinking herds also had high relative risk of culling. The estimate of the sire genetic variance was 0.0472 ± 0.0017 giving a theoretical heritability estimate of 0.11 in the complete absence of censoring. Genetic trends indicated an overall decrease in functional longevity of 0.014 standard deviation from 1995 to 2007. There are opportunities for including the trait in the breeding objective for South African Holstein cattle.  相似文献   
59.
This study compared endometrial cytology vis‐a‐vis uterine fluid cytology for assessment of uterine health in clinically normal and subclinical endometritis (SE)‐affected buffaloes. Uterine fluid samples and endometrial samples were collected from the buffaloes (n = 38) at oestrus using blue sheath and cytobrush, respectively. The smears were stained with Field stain for 3 minutes, and a minimum of 400 cells were counted in each smear for determination of the percentage of polymorphonuclear (PMN) leucocyte. The incidence of subclinical endometritis, based on the cytobrush cytology, was 23.08%. The correlation between cytobrush cytology with uterine fluid cytology was positive and significant (r = .37; p = .02). The ratio of PMN leucocyte in cytobrush cytology to uterine fluid cytology was 1:2.4. ROC analysis revealed that the threshold value of 6.16% PMN leucocyte in uterine fluid cytology showed a diagnostic sensitivity and specificity of 100% in differentiating normal from SE‐affected buffaloes. In conclusion, collection of uterine fluid was easier compared to collection of endometrial samples using cytobrush and the percentage of PMN leucocyte in uterine fluid cytology can be used as a tool for diagnosis of subclinical endometritis in buffaloes.  相似文献   
60.
CASE HISTORY: A one-year-old female goat presented with acute onset of recumbency, seizures and vocalisation approximately 5 hours after being given access to branch trimmings from a neighbour's garden. The plant from which the pruned branches came was subsequently identified as wintersweet (Chimonanthus praecox). Three other goats kept in the same paddock displayed similar clinical signs over a period of 4 hours following the initial presentation.

CLINICAL FINDINGS: All four goats were ataxic, displayed tetanic seizures and were in lateral recumbency; they had dilated pupils and were hyperaesthetic, with elevated heart and respiratory rates. After symptomatic treatment, including sedation with diazepam, one of the three goats continued to deteriorate and was subjected to euthanasia. The remaining three goats recovered over 1–14 days with nursing care and physiotherapy.

DIAGNOSIS: Toxicity due to ingestion of wintersweet, which contains the alkaloid calycanthine.

CLINICAL RELEVANCE: Calycanthine is a central nervous system toxin, causing convulsions. Wintersweet shrubs are present in many New Zealand gardens. Practitioners should be aware that the seeds and flowers, and possibly the leaves, of this plant are highly toxic with signs of toxicity including ataxia, hyperaesthesia and seizures.  相似文献   

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