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21.
We developed PCR-based markers for genotyping Waxy genes in common millet (Panicum miliaceum L.) and proposed a new hypothesis on the origin and dispersal of waxy type of Japanese landraces. I2-K staining indicated that almost all the Japanese landraces had waxy endosperm. Based on the PCR and dCAPs analyses of two waxy loci on different genomes we concluded that there were at least two possible lineages in Asian continent that had independent dispersal pathways into Japan. Most Japanese common millet had the similar genotypes with those in Korean Peninsula but a few particularly from northern part of Japan had common genotypes in northeastern China and Primorskaya Province of Russia.  相似文献   
22.
On the assumption that animals of wild feline species died in the field, caudal epididymal sperm were cryopreserved following storage of the feline epididymides at 20°C for 0-24 hr, and their qualities were observed. Compared to the qualities at 0 hr, no significant differences were noted following 12 hr of storage at 20°C. On comparison of the qualities between caudal sperm cryopreserved after 24 hr storage at 4°C and after 12 hr at 20°C followed by 12 hr storage at 4°C, no significant differences were noted. These findings suggest that the cryopreserved sperm collected from epididymides of dead animals might be useful for artificial insemination if cryopreservation was performed within 12 hr exposure to ambient temperature.  相似文献   
23.
Previously, we developed a simple and efficient method to isolate liver macrophages from a mixed primary culture of adult rat liver cells. To extend the applicability of this method, we isolated macrophages from mixed primary cultures of bovine liver cells. Macrophage cells proliferated on the cell sheet of mixed bovine liver cells after 8-16d of culture. These cells were detached by shaking of the culture flasks. Subsequent transfer and brief incubation in plastic dishes resulted in selective adhesion of macrophages. After rinses with PBS, attached macrophages were harvested. More than 10(6) cells could be harvested from the culture flask at intervals of 2-3d for more than three weeks. The isolated cells were strongly positive for bovine macrophage markers, such as CD68, CD172a and Iba-1. These cells exhibited functional properties of macrophages, including active phagocytosis of polystyrene microbeads, proliferative response to recombinant bovine granulocyte-macrophage colony-stimulating factor, upregulation of specific inflammatory cytokine genes upon stimulation with lipopolysaccharide, and formation of multinucleated giant cells. The shaking and attachment method provides a simple and efficient alternative to obtain bovine liver macrophages without requiring complex equipment or specialized technical skills.  相似文献   
24.
The effects of canopy and shrub layer coverage on the frequency of oviposition by a papilionid butterfly, Luehdorfia japonica, were investigated. Density of larval host plant tended to be higher where shrub layer was thinner, and the frequency of oviposition was correlated with host plant abundance. On the other hand, host plant abundance and the frequency of oviposition were not correlated with canopy layer coverage. Eggs were mainly found at or near the forest edge irrespective of host plant abundance.  相似文献   
25.
This study aimed to determine the usefulness of colour and pulsed Doppler modes for the accurate diagnosis of donkeys suffering from subfertility to determine whether testicular vascularity assessment could be an indicator for sperm functionality. The study sample was composed of 10 male donkeys with normospermia (control group) and 10 donkeys with hypospermia. Animals underwent scrotal circumference measurement, testicular Doppler examination, seminal evaluation, blood sampling and hormonal assay. Semen volume and concentration were significantly (p ≤ .05) lower in the subfertile group (30.25 ± 1.22 ml and 89.44 ± 2.55 × 106/ml) as compared with the control group (82.76 ± 1.65 ml and 452.78 ± 1.25 × 106/ml), and total sperm/ejaculation was significantly (p ≤ .05) higher in the normal donkeys (28.30 ± 2.32 × 109/total ejaculated) as compared with the subfertile group. Intratesticular coloured area showed a marked decline in the hypospermic males. There was no significant difference between the two groups in testosterone level, although the normal group showed an increase in nitric oxide metabolites. Both Doppler indices of the three branches of the testicular artery were elevated significantly (p ≤ .05) in abnormal donkeys, whereas Doppler peak systolic and end-diastolic velocities were increased in the normal group. Male donkeys with subfertility demonstrated lower arterial vascularity parameters in the form of intratesticular coloured area and blood flow rate; therefore, the most optimal parameters for differentiating subfertile hypospermic from normospermic donkeys were found to be the two Doppler indices, velocities parameters, testicular blood flow rate and nitric oxide levels.  相似文献   
26.
An 11-year-old female miniature schnauzer was tentatively diagnosed with the skull base meningioma, based on several examinations. Because surgical treatment was difficult, and outpatient radiation therapy was not available in the local area, chemotherapy with hydroxyurea combined with dexamethasone was selected. The patient's clinical symptoms improved after one week of treatment, and the tumor size was obviously reduced on MRI performed 37 days after treatment began. The patient received hydroxyurea for 7 months, with symptoms remaining stable, and the tumor re-increased to almost the same size at 7 months as that at the initial examination. At that time, hydroxyurea was discontinued. The patient died from pulmonary edema 14 months after treatment began. Pathologically, the tumor was diagnosed as a meningioma.  相似文献   
27.
Studies pertaining to cholesterol requirement are limited based on the levels evaluated and statistical analysis. Two trials were conducted to refine cholesterol requirement in Pacific white shrimp Litopenaeus vannamei feeds. The basal diet was supplemented with graded levels of cholesterol (ranging from 0.48 to 1.85 g/kg) in trial 1. Since the shrimp (initial weight: 0.24 g) growth response was very linear without reaching a plateau, it was not clear whether the requirement was met. Hence, a second trial was designed using eight diets designed with an increased range of cholesterol levels from 0.45 to 4.57 g/kg of diets. The shrimp (0.38 g initial weight) reached a final weight of (4.31–7.43 g) or per cent weight gain from 1,014%–1,874% (n = 4) after 6 weeks. Saturation kinetic model and broken‐line models with linear or quadratic ascending portions were used to evaluate dose–response relationships of feed efficiency (FE), thermal‐unit growth coefficient (TGC), whole‐body cholesterol (CHOL) and cholesterol deposition (CHOLD) against dietary cholesterol. The cholesterol requirement of shrimp was estimated at 1.9 (1.1–4.3) g/kg, 1.7 (1.1–3.4) g/kg, 2.5 (2.3–2.9) g/kg and 2.7 (2.4–3.1) g/kg of shrimp diet for FE, TGC, CHOL and CHOLD, respectively. Additionally, based on improved growth, the inclusion of phytosterol can serve as a partial replacement for cholesterol.  相似文献   
28.
In order to monitor lead pollution from urban areas to coral reefs in the Gulf of Thailand, linear and two-dimensional distributions of Pb in corals from Khang Khao Island, Thailand and Rukan-sho, Okinawa, were analysed with high resolution. Laser ablation inductively coupled plasma mass spectrometry was applied to measure Pb content in coral skeletons using synthetic Pb standards in a CaCO3 matrix as calibration materials. Linear and two-dimensional ablation schemes were applied to determine the Pb content in corals collected from Khang Khao Island, Thailand and Rukan-sho, Okinawa. The coral skeleton was ablated by Nd:YAG laser (wavelength of 266 nm, beam diameter of 155 µm, scanning speed of 10 µm s?1 and frequency of 10 Hz) along the growth axis, and ion counts for 208Pb were normalised to 42Ca. Lead content in the corals was determined using a calibration curve obtained from the synthetic Pb standards (0–141 µg g?1). The linear ablation track of the sample from Khang Khao showed over 30 peaks of Pb with an average value of 3.55 µg g?1, while Pb content in the coral from Rukan-sho showed relatively small variation with an average value of 0.132 µg g?1. Two-dimensional imaging of Pb in the coral skeletons was also carried out for an area of 7?×?20 mm on the sample from Khang Khao. The distribution patterns of Pb and Ba in the Thailand coral co-varied. These observations from the linear and imaging analyses suggest discontinuous inputs of anthropogenic Pb from rivers to the Gulf of Thailand.  相似文献   
29.
It is known that selenium (Se) has various functions in animals. Many investigations on the biochemical and physiological effects of Se have been previously reported; however, the detailed function of Se in reproduction is not yet clear. We proposed the possibility that Se plays a notable role in progesterone production. The aim of this study was to clarify the effects of Se supplementation on progesterone levels of pregnant Holstein heifers. Eight Holstein heifers (?Se) were fed basal diet (containing 0.022 ppm of Se) throughout the experiment. While a 0.3 ppm diet of Se (sodium selenite) was fed to another seven animals (+Se) with basal diet. Blood sampling was carried out every week. Plasma Se concentrations were higher in Se‐supplemented cows compared with controls (?Se) (P < 0.01) throughout the experiment. Se supplementation increased plasma progesterone in the 29–39 weeks of pregnancy from 4.98 ± 0.64 to 6.86 ± 0.49 ng/mL on average (P < 0.05). The present findings suggest that Se contributes to maintaining the function of the corpus luteum and/or placenta in the latter period of pregnancy.  相似文献   
30.
A battery of mouse monoclonal antibodies (mAbs) reactive with porcine peripheral blood (PB) leukocytes was generated. Among the mAbs, 6F10 was found to react probably with cluster of differentiation (CD)8 alpha-chain, while 7G3 and 3E12 were found to recognize gammadelta T-cells, as revealed by two-color flow cytometric and immunoprecipitation studies. 7G3 was shown to react with the constant (C) region of the T-cell receptor (TCR) delta-chain by the following facts: (1) 7G3 immunoprecipitated full-length TCR delta-chain protein fused with glutathione S-transferase (GST) produced by Esherichia coli and (2) 7G3 reacted with TCR delta-chain expressing Cos-7 cells transfected with either full-length or N-terminal deleted mutant cDNA, but did not react with Cos-7 cells transfected with C-terminal deleted mutant TCR delta-chain cDNA. All three mAbs produced high-quality immunostaining results on frozen sections, revealing a distinct distribution of gammadelta T-cells and CD8(+) cells. This report precisely characterizes mAbs against porcine TCR for the first time, facilitating molecular biological investigations of the porcine immune system.  相似文献   
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