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1.
以38种1 153份豆科植物种子为研究对象,测定了其在中期库储存4~7年后种子发芽率的变化状况,判断是否需要继续监测或直接扩繁。结果表明:5年后无需监测直接扩繁的种子有饭豆、柱花草、田菁、小豆和银合欢等5种(同一草种,发芽率降低超过20%的份数占总数的百分比小于5%且发芽率升高的份数占总数的百分比大于70%);无需监测无需扩繁的种子有白三叶、杂三叶、黄花苜蓿、黄芪、野大豆等9种(发芽率降低超过20%的份数占总数的百分比大于60%);需要监测的种子有紫花苜蓿、沙打旺、草木樨、岩黄芪、红豆草等24种(发芽率变化在以上2个范围之外,则需要继续监测)。  相似文献   

2.
<正>近年来,随着全社会环保和节约资源意识的不断提高,有机微量元素产品的开发和研究工作发展非常迅速,并且有很多品种已经被列入农业部1126号公告《饲料添加剂品种目录(2008)》中,蛋氨酸铬就是其  相似文献   

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4.
Total hip endoprotheses are a good possibility for treatment degenerative wear and pathologic damage of the hip joint in man as well as in dogs. However, aseptic loosening of the protheses, especially in the area of the shaft, is still a problem in conventional total hip endoprotheses. The purpose of the present study was to use the finite-element-analysis (FEA), to enhance endoprothetic design and to prevent loosening of protheses. In order to simulate the femur of the dog for numerical analysis, a material law for the compacta in the femur of the dog was developed. The elastic properties of the compacta were experimentally determined by using compression tests of bone samples of euthanised dogs. The results show constant denseness and a constant axial elastic modul in the compacta.  相似文献   

5.
The purpose of this study was to determine the magnetic resonance (MR) imaging characteristics of bone marrow in the pelvis and femur of normal, young dogs. Six greyhounds were imaged at 4, 8, 12, and 16 months of age. Sagittal images of the femur and dorsal images of the pelvis were obtained with T1-weighted, fast spin echo (FSE) T2-weighted, and short tau (T1) inversion recovery (STIR) sequences. On T1-weighted images areas with high signal intensity, similar to fat, included the femoral heads, mid-diaphysis of the femur, femoral condyles, and the body of the ilium. T2-weighted images were characterized by uniform intermediate signal intensity (less than fat, but greater than muscle) in the femoral head, high signal intensity, similar to fat, in the mid-diaphysis of the femur and ilial body, and intermediate to high signal intensity in the femoral condyle. By 16 months high signal intensity was seen in the diaphysis and distal metaphysis on both T1- and T2-weighted images. On STIR images the femoral head had intermediate to low signal intensity, compared with muscle. The mid-diaphysis of the femur was of low signal intensity, similar to fat, and the body of the ilium had mixed signal intensity at all ages. The femoral condyle had inhomogenous, intermediate to low signal intensity at 4 months, but was of uniform low signal intensity at 8-16 months.  相似文献   

6.
<正>猪痢疾是一种传染性黏膜出血的腹泻疾病,由定植于肠道的猪痢疾短螺旋体引起,能够诱发盲肠和结肠发炎。据报道饲料中添加菊苣根和甜羽扇豆可预防猪痢疾。本试验旨在验证是菊苣根中的菊粉  相似文献   

7.
The results of surgical treatment of 10 subchondral bone cysts, all located in the medial femoral condyle, are presented. A cancellous bone graft was used in nine cases and a two component acrylic bone cement was used in the case of an extremely large cyst. Eight out of the 10 cases made a satisfactory clinical recovery.  相似文献   

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OBJECTIVE: To determine whether medullary reaming alone, or followed by cemented hemiarthroplasty, influenced porosity, vascularity, and new bone formation in the proximal portion of the femur in dogs. ANIMALS: 12 adult mixed-breed dogs. PROCEDURE: Unilateral femoral head and neck excisions were performed, followed by femoral medullary reaming in 6 dogs and femoral medullary reaming and cemented hemiarthroplasty in 6 dogs; the contralateral femur was used as a control. All dogs were euthanatized 28 days after surgery, and femurs were harvested. Vascularity, porosity, and new bone formation were quantified for all femurs of dogs from both groups at 3 proximal-to-distal levels, 3 regions (periosteal, midcortical, and endosteal), and 4 quadrants (cranial, caudal, medial, and lateral) of the femur. RESULTS: Medullary reamed and cemented hemiarthroplasty femurs had significant increases in vascularity and porosity at all levels and in new bone formation at levels 2 and 3. Porosity was increased significantly in the periosteal region of the cemented hemiarthroplasty (9.7+/-0.7%), compared with control (2.3+/-0.2%) and medullary reamed (8.4+/-0.7%) femurs. Porosity was increased in the caudal and medial quadrants in the medullary reamed and cemented hemiarthroplasty femurs; vascularity results were similar. CONCLUSION: Increased porosity, vascularity, and new bone formation in reamed and cemented hemiarthroplasty-treated femurs supports the theory that surgical trauma associated with medullary reaming is an important factor in early cortical bone loss after hip arthroplasty. CLINICAL RELEVANCE: Femoral remodeling associated with reaming and broaching is appreciable but may be only a temporary response, whereas other factors may be responsible for chronic cortical bone loss.  相似文献   

10.
The proximal portion of the femur was evaluated as a source of autogenous cancellous bone in dogs. Bilateral oval cortical defects were created in the lateral subtrochanteric area of the femur in 16 dogs. Cancellous bone was removed and the weight recorded. Cancellous bone was similarly harvested from the proximal portion of the humerus in 7 of these dogs. Subtrochanteric femoral defects in 11 dogs were randomly assigned to receive cancellous bone graft obtained from the femur (n = 4) or the humerus (n = 7). Subtrochanteric defects in 5 dogs were not grafted. Radiographic assessment of subtrochanteric defects was performed at 4-week intervals, and histologic assessment at 4, 8, 16, and 24 weeks after surgery. Nongrafted donor sites healed by ingrowth of trabecular bone during the first 12 weeks after surgery. By week 24, the lateral cortical wall had reformed, but remodeling was incomplete. Donor sites grafted with cancellous bone healed similarly, but with more rapid healing and more complete remodeling evident by week 24. Although the mean weight of cancellous bone harvested from the proximal portion of the femur (0.82 +/- 0.22 g) was significantly (P less than 0.05) less than that harvested from the proximal portion of the humerus (1.38 +/- 0.29 g), there was no qualitative histologic or radiographic difference in bony healing of grafted defects. We determined that the proximal portion of the femur can be safely used to provide moderate amounts of cancellous bone, and that a second bone graft can be collected from the same subtrochanteric donor site after 12 weeks.  相似文献   

11.
In this study, dual energy X-ray absorptiometry (DXA) was performed on the calcaneus (CAL) and accessory carpal bone (ACB) of early-age neutered (n = 11) and sham-operated puppies (n = 10) to investigate changes in bone mineral density (BMD) and bone mineral content (BMC) over time. Prepubertal ovariohysterectomy and sham surgery were performed at 10 weeks, while BMD and BMC were measured at 12, 16, 20 and 24 weeks of age. BMD and BMC of CAL and ACB of ovariohysterectomised puppies were found to be higher. The differences between the groups were statistically unimportant; however, the fourth measurement of the ACB showed a significant (P < 0.05) difference. Sexually intact puppies weighed less than gonadectomised puppies in all measurements. Because of the positive correlations between body weight and bone mineral density, BMD and BMC of early-age neutered puppies were found to be higher. These results suggest that BMD and BMC are not affected by prepubertal ovariohysterectomy until six months of age in mixed-breed puppies.  相似文献   

12.
A safe, non-invasive method for the accurate measurement of bone mineral content in the third metacarpal bone of the horse is described. The technique involves scanning the bone with a single photon beam from an Americium-241 source. Data were obtained from the excised metacarpal bones from both forelimbs of 50 normal and seven lame horses. Measurements were made in vivo on eight normal and seven lame horses and on one experimental horse with osteopenia induced by partial weightlessness in a flotation tank. In the normal horses bone mineral content altered with age, particularly in the first six months of life. There were also differences according to the site of scanning on the metacarpus. The contribution of the splint bones to the total bone mineral content was less than 2 per cent distal to the mid-point of the metacarpus, but in the proximal shaft it increased to 12 per cent. No significant differences were noted either between right and left limbs, or between male and female animals. A reduction in bone mineral content was demonstrated in the affected leg of horses with chronic lameness and with osteopenia induced by weightlessness. The bone mineral content (g/cm) correlated well with the ash content (mg/100 mg dry bone weight), the specific gravity and the apparent transverse velocity of ultrasound (m/sec) through the bone. A measure of bone mineral density (g/cm3) was calculated from the bone mineral content and cross sectional area of the bone to overcome the individual differences in size of the metacarpus.  相似文献   

13.
14.
In order to elucidate the relationship between cellular injury and lipid peroxidation induced by hexavalent chromium (CrVI), isolated rat hepatocytes treated with any one of scavengers of active oxygen species, antioxidants or antichromium agent were incubated with K2Cr2O7 as CrVI (1 mM Cr). After the incubation, the development of lipid peroxidation was determined as thiobarbituric acid (TBA)-reacting materials in total lipid extracts from the incubated hepatocytes. Cellular injury was observed as a leakage of lactate dehydrogenase (LDH) from hepatocytes into incubation medium. The contents of reduced glutathione (GSH) in hepatocytes were also assessed. Results obtained were as follows: (1) CrVI facilitated lipid peroxidation in isolated hepatocytes after 20 min of incubation. On the other hand, the cellular injury induced by CrVI was barely observed even after 60 min of incubation. (2) The CrVI-induced lipid peroxidation was inhibited by catalase and mannitol as scavengers of active oxygen species, or N,N'-diphenyl-p-phenylenediamine and alpha-tocopherol as antioxidants. However the cytotoxicity of CrVI could not be prevented by these chemicals. (3) CrVI depleted the contents of intracellular GSH and diminished the activities of glutathione reductase (GR) and glutathione-S-transferase (GST) except glutathione peroxidase. (4) The scavengers of active oxygen species and the antioxidants could not prevent the depletion of intracellular GSH induced by CrVI. (6) Ascorbic acid, antichromium agent, prevented all of the lipid peroxidation, the cellular injury and intracellular GSH depletion induced by CrVI.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

15.
本文研究了双氧水(H2O2)催化法与GB/T6432-94法对粗蛋白质含量测定的影响.结果表明:以H2O2为催化剂的检测方法检测快速、结果准确、投资较少,防止污染,改善操作环境,安全可靠等特点.是蛋白质测定方法的一种快捷可靠的方法.  相似文献   

16.
Variation in the phosphorus content and specific gravity of bone samples taken from the 11th, 12th and 13th ribs of cattle was examined in relation to the selection of a site for the acquisition of such samples by biopsy, in experiments where changes in skeletal phosphorus storage required to be monitored. The degree of mineralisation of the 11th rib was significantly higher than that of the 12th, which in turn was greater than that of the 13th. It was concluded that valid comparisons may be made between bone samples obtained during an experimental regime, provided they are taken from the same numbered rib; it is recommended that the 13th rib be avoided in such studies.  相似文献   

17.
The objective was to determine signalment-related differences in bone mineral content (BMC) and bone mineral density (BMD) in dogs. Unilateral appendicular bones were harvested from 62 canine cadavers. Mid-diaphyseal regions of interest (ROIs) were scanned using a Hologic DXA device Braincon, Vienna, Austria). BMC and BMD were calculated within this region. Middle-aged dogs (3-10 years) revealed the highest BMC and BMD levels. Mean BMC and BMD were higher in males compared to females. Furthermore, body-weight of the male dogs was significantly higher compared to the females (P < 0.0001). Body weight and bone length were significantly associated with BMC and BMD (P < or = 0.023) in all bones but the radius. These data suggest that BMC and BMD appear to be highest in male large-breed dogs with a body weight greater than 30 kg. These results may help determine risk factors in fracture development and healing.  相似文献   

18.
In a recent study, we found that the distal rat jejunum is able to secrete K+ under in vitro conditions. The question therefore arises as to whether the small intestine might participate in K+ homeostasis. Consequently, this study examined the influence of the dietary K+ content on transepithelial K+ transport in rat jejunum. Rats were fed two diets differing in K+ content (control diet 4.0 g K+/kg, low K+ diet (LK) 0.27 g K+/kg). After a minimal feeding period of 7 days, distal jejunal sheets were mounted in Ussing chambers and unidirectional 86Rb+ fluxes (as a marker for K+ transport) were measured under short‐circuit conditions. Jejunum obtained from rats fed the control diet showed a net K+ secretion of 200 nmol Rb+/h/cm2. Unidirectional Rb+ fluxes were smaller in distal jejunum from rats fed the LK diet. In these tissues, glucose‐induced short‐circuit current and tissue conductance were also smaller than in controls. However, net Rb+ fluxes were not significantly different in small intestine from K+‐restricted rats compared with jejunum from control animals. Based on the observation that the dietary K+ content does not affect transepithelial net K+ transport, we conclude that transcellular K+ secretion by the small intestine is not involved in K+ homeostasis.  相似文献   

19.
The acute phase response as indicated by serum haptoglobin and total haemolytic complement activity (CH50) was measured in 72 cross-bred steer calves purchased at sales in Ontario. During the 28 day (d) trial, 18 steers were randomly assigned to each of the following groups: 1) control; 2) vaccinated (Infectious Bovine Rhinotracheitis, Parainfluenza-3, Bovine Viral Diarrhea, Bovine Respiratory Synctial Virus vaccine plus Pasteurella haemolytica vaccine); 3) supplemental chelated Cr (0.14 mg/kg); and 4) Cr plus vaccines. Haptoglobin concentrations were low at arrival, increased (P < 0.05) on day 7, and returned to near initial levels (P > 0.05) by day 14. Supplemental Cr reduced (P < 0.05) haptoglobin on day 7 when morbidity was highest. Following antibiotic treatment for respiratory disease haptoglobin was lower (P < 0.05) than during morbidity; however, during morbidity, haptoglobin concentrations were not greater in sick calves (P > 0.05) than in healthy calves. Complement activity was lowest on day 7 (P < 0.05) and peaked on day 14 (P < 0.05). Complement activity tended to be lower on day 7 for vaccine, Cr, and Cr+ vaccine groups; however, the difference from controls was not significant (P > 0.10). Complement activity did not increase on day 14 (P > 0.05) with Cr supplementation as in other treatments. Morbid calves had lower (P < 0.05) CH50 activity than healthy calves on day 14. Following antibiotic treatment, the Cr-supplemented group had higher (P < 0.05) CH50 than during morbidity. In general, chromium supplementation reduced the acute phase response in newly arrived feeder calves.  相似文献   

20.
Emperipolesis of hematopoietic cells within megakaryocytes was found in rats. The incidence was less than 0.3% in young rats (2 to 12 months old) but increased to 2-5% among the aging rats (18 to 24 months old). The incidence increased markedly in hyperplastic bone marrow secondary to chronic suppurative or neoplastic lesions. Mature neutrophils appeared to be the most common marrow cell engulfed by megakaryocytes. By light microscopy, engulfed cells were separated from megakaryocyte cytoplasm by a narrow pericellular space. By electron microscopy, marrow cells engulfed by megakaryocytes were located in the open canalicular system. Cell membranes of both engulfed cells and megakaryocytes were intact, and there was no fusion of cell membranes or phagosome formation in the megakaryocytes.  相似文献   

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