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1.
根据JJF1059-1999《测量不确定度评定与表示》建立了高效液相色谱法测定鸡肉中土霉素残留测量的不确定度评定方法,评定过程包括建立测量程序、分析不确定度来源、对不确定度分量进行量化。将不确定度归类为两大类。随机效应导致的不确定度可以通过一系列具有统计意义的重复观测值进行A类评定;系统效应导致的不确定度通过各测量器具、设备的说明书、校准证书提供的参数进行B类评定。本方法鸡肉中土霉素残留量的相对合成标准不确定度约为3.9%。  相似文献   

2.
The origins of the motor nerve fibers supplying the individual hindlimb muscles were elucidated in the fowl by the retrograde degeneration method. Chromatolytic cells were seen in the ipsilateral lamina 9 of the lumbosacral enlargement. Motoneurons innervating the individual hindlimb muscles were localized in the characteristic position of lamina 9. Both hip and thigh muscles are supplied by motoneurons of almost all the columns in lumbar segments and by those of dorsolateral columns in sacral segments, while the shank and foot muscles are supplied by motoneurons of ventromedial columns in sacral segments. The origins of the dorsal cord of the lumbosacral plexus are situated laterally in the lamina 9 and those of the ventral cord are located medially in it.  相似文献   

3.
The present study examined the ultrastructure of the choroid plexus of the lateral ventricle of the horse. The material was fixed in 2.5% glutaraldehyde in 0.1 m sodium phosphate buffer, pH 7.3, processed and analysed by scanning electron microscopy. The choroid plexus was characterized by regions with a predominance of villi, which resembled finger-like projections or bunches of grapes, and others where straight and uniform folds predominated. Epithelial cells projected into the ventricle and large amounts of cilia and microvilli were observed on their surface. The choroid glomus corresponded to a dilatation of the choroid plexus and was characterized by blood vessels of different calibres surrounded by connective tissue.  相似文献   

4.
The origins of the motor nerve fibers supplying the individual forelimb muscles were elucidated in the fowl by the retrograde degeneration method. Chromatolytic cells were seen in the ipsilateral lamina 9 of the cervical enlargement. Motoneurons innervating the individual forelimb muscles occupy the restricted area in the lamina 9. The muscles acting on the shoulder joint are supplied by motoneurons of the more cranial segments and the others acting on the elbow and the more distal joints by those of the more caudal ones. The origin of the dorsal cord is situated laterally in the lamina 9 and that of the ventral cord is located medially in it.  相似文献   

5.
The changes in the structure of nuclei and nucleoli are good markers of the changes in the activity of epithelium cells of oviducts in cows during the sexual cycle. They are manifested by the changes in the proportion of condensed chromatin and interchromatin. In the secretory as well as ciliary cells, the maximum proportion of interchromatin is recorded in pro-oestrus and oestrus, whereas in metoestrus it is the proportion of condensed chromatin that increases. Metoestrus is characterized by the segregation of nucleoli and by the formation of ring-like nucleoli which partially persist also in dioestrus and in some cells throughout the cycle. Invaginations of the nuclear membrane (which are levelled off later) occur on many nuclei at the end of metoestrus and in dioestrus. Single nuclear bodies occur in the nuclei and the frequency of the the occurrence of interchromatin granules changes. Dilation of perinuclear spaces can be observed in the secretory cells, mainly in the period of oestrus.  相似文献   

6.
The luminal appearance of the various ducts of the epididymis of the ostrich was studied by scanning electron microscopy in tissues fixed by immersion in glutaraldehyde. The ductal types were similar to those previously described for some other species of birds. Numerous short microvilli, as well as a single cilium, projected from the apical surface of the rete testis cell. The ciliated cells of the efferent ductules projected tufts of cilia into the ductal lumen, while the non-ciliated cells bore short microvilli. The connecting and epididymal ducts were lined by a columnar cell type whose apical surface bore uniformly distributed microvilli and a single, centrally situated cilium. The spermatozoa found in all ducts of the epididymis bore a distal cytoplasmic droplet. This observation has implications for the maturational process in the ostrich spermatozoon in the epididymis. The surface features of the ducts, except for a few noteworthy differences, were generally similar to those previously described for the male domestic fowl, turkey and duck.  相似文献   

7.
Blood serum samples collected from two cattle herds were examined by the immunodiffusion test (ID), pseudotype neutralization test (PsNT) and ELISA procedure for the presence of antibodies to the bovine leukosis virus. The spectrophotometric readings of the ELISA procedure were evaluated on the basis of the arithmetical mean (means) and standard deviation (Sd) of the values obtained in negative controls. The examination of 208 samples of serums taken in the negative herd confirmed in all cases a negative reaction in the ID and PsNT tests. In all samples the ELISA reaction values remained within the range delimited by the relation of means + 3 Sd, which was defined as the threshold value of positive reaction. Out of the 223 serum samples of the positive herd, 132 samples were within the range below means and five of them were leukosis-positive in PsNT. Twenty-nine samples were within the range of means to means + 3 Sd; five of them were found positive in PsNT and three in the ID test. Sixty-two samples were above the threshold value of positivity; of these, positivity was confirmed in 58 cases by PsNT and in 55 cases by ID. As the results suggest, the ELISA procedure is suitable for the detection of animals positively reacting to bovine leukosis, to which special attention should be paid.  相似文献   

8.
Stimulation of the crop by injections of water or saline produced electroencephalogram (EEG) arousal. Inflation of an implanted crop balloon by air alone had no effect if done slowly over 30 s. Inflation by ice water was more effective than by air, water at 40 °C or saline. Crop volume does not appear to be reflected in the EEG.  相似文献   

9.
The present study describes in detail the venous supply to the bovine cecum, ileum, and the proximal loop of the ascending colon. The cecum was supplied by branches from the cecal and accessory cecal veins. The accessory cecal vein was observed in the majority of the specimens examined. The cecal and accessory cecal veins were joined by 7–10 short oblique anastomoses. The ileum was supplied by the ileal branches of the cecal vein, and from the mesenteric ileal and first ileal (cranial mesenteric) veins. The ileal branches of the cecal vein formed a row of antimesenteric ileal arches in the ileal part of the ileocecal fold. The mesenteric ileal vein, in some cases, detached a collateral branch. The first ileal and the mesenteric ileal veins anastomosed on the ventral surface of the ileum. The initial loop of colon was supplied by branches from the ileocolic vein. In the majority of specimens, the common colic, a branch of the cranial mesenteric vein, supplied the first colic branch to the third part of the initial colon. In such cases, the ileocolic vein gave off only the second and third colic branches. However, in one case, the proximal loop of the ascending colon was supplied by three colic branches of the ileocolic vein and by the first colic branch of the common colic vein. In specimens in which the common colic vein was absent, the colic branches to the initial colon were all given off by the ileocolic vein. The third (or fourth) colic branch of the ileocolic vein and the first cecal branch of the cecal vein united on the lateral surface of the ileocecocolic junction to form an ileocecocolic arch. The veins on the medial surface of the ileocecocolic junction did not form an arch. The colic and ileal lymph nodes were supplied by twigs from the colic branches of the ileocolic vein and first ileal vein of the cranial mesenteric, respectively. The small cecal lymph nodes seen only in the specimen from the calf were supplied by fine branches from the cecal vein.  相似文献   

10.
Under continuous IV infusion of oxytocin, milk leakage was elicited in 6 lactating cows with full udders by induction of a vacuum (-30 cm of water) around 1 mammary papilla (teat) with a plethysmographic apparatus. The volumes of milk loss were measured every minute. Epinephrine injected either into the jugular vein (20, 100, and 500 micrograms) or into the external pudic artery (1.5, 7.5, and 37.5 micrograms) induced an increase in milk leakage in 5 cows. This effect could be antagonized by the beta-blocking agent sotalol hydrochloride (0.5 to 4 mg) injected into the external pudic artery. In 1 cow, however, epinephrine given intra-arterially exerted a biphasic effect, small doses inducing stimulation, and large doses evoking inhibition of milk loss. The stimulating effects were blocked by sotalol (2 mg). The inhibiting effects were antagonized by the alpha-blocking agent prazosin (2 mg).  相似文献   

11.
The degree of depolarisation in a nociceptor created by a painful stimulus is influenced by numerous substances, including nerve growth factor, prostanoids, substance P and a range of inflammatory mediators. In the dorsal horn of the spinal cord, the frequency of an action potential may be increased or decreased by neurotransmitters, including substance P, calcitonin gene-related peptide, galanin, γ-amino butyric acid and glycine, as well as pro-inflammatory substances. The perception of pain can also be altered in the brain, where the sensation of pain is cognitively integrated. A range of analgesic drugs with different mechanisms of action are available for selection by veterinarians for pain relief.  相似文献   

12.
120 male rats belonging to two different strains (Han: WIST, Han: SPRD) and two different weight groups (group I: lighter body weight, group II heavier body weight) were killed on three different methods (decapitation, Nembutal -overdose greater than 250 mg/kg b.w. i.p. less than, exsanguination in Nembutal -anaesthesia greater than 100 mg/kg b.w. i.p.). Subsequently, changes in tubuli contorti I of the left kidneys were examined morphometrically. The mean total area, luminal area and epithelial area were evaluated as well as the mean diameter of the tubular nuclei. Concerning the areas of the proximal tubules only the luminal areas show differences between the Wistar and the Sprague-Dawley strain. The total, luminal and epithelial area in the rats belonging to the weight group II were significantly larger than in the rats belonging to weight group I. With one exception this could be noticed within both strains and all three modes of killing. In both strains and weight groups the rats were killed by Nembutal -overdose or exsanguination showed significantly smaller total, luminal and epithelial areas than the rats that were decapitated. Possible cause heretofore are discussed. Differences between the tubular areas of the rats that were killed by Nembutal -overdose and those that were killed by exsanguination after Nembutal -anaesthesia could not be established. The measurements of nuclei diameters in the proximal tubules did not lead to clearly different results between both strains, weight groups and the various modes of killing.  相似文献   

13.
Flushing the vasa deferentia (ductus deferentes) at the time of vasectomy reduced to zero the number of intact spermatozoa by postvasectomy day 6 in the dog and by postvasectomy day 7 in the cat and shortened the time from vasectomy to azoospermia in the dog, but not in the cat. The fluid used to flush the vasa deferentia was not eliminated through the penile urethra, but flowed into the urinary bladder, indicating that the least resistant pathway for the exit of vasal content in the anesthetized dog and cat is toward the urinary bladder. Both control and treated dogs and cats had spermatozoa in the urine obtained by cystocentesis immediately after ejaculation or ejaculation and flushing of the vasa deferentia. Flushing the vasa deferentia at the time of vasectomy is easy to do, safe, and can be used in clinical practice to decrease the time from vasectomy to the safe utilization of dogs and cats as teasers. The procedure has potential application to males of other species.  相似文献   

14.
OBJECTIVE: To characterize the bacteria of the genital tract in adult cats; assess the effect of estrus, mating, and administration of progestins on those microorganisms in females; and evaluate whether results of bacteriologic culture of vaginal swabs are affected by cleansing of the vulva prior to sampling or by repeated sampling. ANIMALS: 66 female and 29 male cats undergoing routine ovariohysterectomy or castration. PROCEDURE: Specimens were obtained from vaginal and uterine or preputial mucosae with swabs moistened with sterile saline (0.9% NaCl) solution. In 9 cats, vaginal specimens were obtained before and after cleansing of the vulva with ethanol; in 7 female cats, 2 vaginal speci mens were obtained in immediate succession. RESULTS: Aerobic bacteria were most commonly isolated from cats' vaginas and prepuces; anaerobic bacteria were isolated frequently from males (41%) but rarely from females (5%). Generally, culture results were not affected by cleansing of the vulva or repeated vaginal sampling. The bacterial population of the vaginas of cats was influenced by stage of the estrous cycle but not by mating or administration of progestins. Bacteria were not isolated from the uterus of any cat. CONCLUSIONS AND CLINICAL RELEVANCE: In cats, bacteria of the genital tract in females are predominantly aerobic; in males, aerobic and anaerobic bacteria are found. The bacterial population of the vagina is affected by stage of the estrous cycle. Pure growth of bacteria in culture of genital tract specimens is a normal finding; antimicrobials should only be administered if clinical signs of genital infection are present.  相似文献   

15.
旨在探讨钙稳态失衡在锰致体外培养鸡胚脑神经细胞凋亡中的作用。以体外培养鸡胚脑神经元为研究对象,在含终浓度为0、1.5、22、.5 mmol.L-1MnCl2的DMEM培养液中培养24 h,应用流式细胞仪检测磷脂酰丝氨酸(PS)和线粒体膜电位(ΔΨm),琼脂糖凝胶电泳法(DNA Ladder)检测细胞染色质的断裂,以Fura-3/AM为探针检测细胞内游离钙离子浓度([Ca2+]i),用实时定量PCR法检测细胞内CaMmRNA的表达水平。结果表明,随着MnCl2浓度的升高,ΔΨm呈降低趋势,PS膜外翻增加,细胞染色质DNA发生损伤,产生明显的梯形条带,细胞内[Ca2+]i呈升高趋势,CaMmRNA的表达水平下降。结果提示,过量锰通过抑制CaM活性,引起神经元内[Ca2+]i升高,膜通透性发生改变,ΔΨm降低,从而导致鸡胚脑神经元发生凋亡。  相似文献   

16.
The drainage of the thoracic limb of the Van cat was performed by the superficial and deep vein systems. The superficial system was constituted by the cephalic vein and its branches. The deep vein system was constituted by the axillary vein and its branches. The two vein systems anastomosed with each other at various points along their courses. The cephalic vein emerged from the external jugular vein together with the superficial cervical vein. The axillary vein continued the subclavian vein. It ran caudoventrally and gave off the subscapular vein, at the level of the shoulder joint, then gave off two independent branches, which were the external thoracic veins. Then the rest of the vessel continued as the brachial vein. The thoracodorsal vein was formed by the communicate ramus vein which arose between the subscapular vein and the brachial vein. The cranial circumflex humeral vein arose double from the subscapular vein. One of them anastomosed with the deep brachial vein and the other one drained the biceps and the deep pectoral muscles. The cranial interosseous vein from the caudal aspects of the brachial vein and passed the interosseous space of the antebrachium then ran to the lateral aspect of the forearm. The caudal interosseous vein arose from the ulnar vein (in two specimens) and the median vein together with the ulnar vein (in two specimens) or independently from the median vein (in one specimen). Although many similarities were found in the veins of the thoracic limb of the Van cat as compared with the domestic cat, some significant differences were noted in the origin, course, anastomosing and ramification of veins of the thoracic limb.  相似文献   

17.
The motor cortex was transcranially and peripheral nervous structures (motor roots, plexus, peripheral nerves) were percutaneously stimulated by magnetic pulses in awake dogs and in dogs awaking from general anesthesia. The compound muscle action potentials were recorded by surface or needle electrodes. The central motor conduction time as an information about central motor tracts was obtained by subtracting the peripheral latency from the corticomuscular latency. The peripheral latency was assessed by high voltage electrical and magnetic stimulation of motor roots and by the F-wave technique. The motor conduction velocity of the tibial nerve was measured by percutaneous magnetic and by electrical stimulation and the resulting values were compared.  相似文献   

18.
Developmental changes in the mucous membrane of the rumen in bovine fetuses were observed by scanning electron microscopy (SEM). The ruminal epitheliums were obtained from 20 bovine fetuses and 4 bovine neonates. The samples were divided into 3 groups. Group 1 was examined in the epithelial surface by SEM. Group 2 was examined in the surface of the lamina propria and the reverse face of the epithelium by SEM, after having separate the epithelium from the lamina propria by Scallata's PBS-EDTA method. Group 3 was examined in histological aspect.
The ruminal papillae appeared first in early in the 5th month of gestation. On the other hand, the papillae of the lamina propria appeared first in early 4th month or late 4th month of gestation. It seemed that the formation of papillae in the lamina propria always preceded that of ruminal papillae. Meanwhile, some epithelial cells were exfoliated from the ruminal surface cells during late 4th month to early 5th month of gestation. Ruminal surface cells came to have keratohyaline granules from the 5th month of gestation onward.  相似文献   

19.
The anatomy of the a circumflexa ilium profunda supplying the flank of the sheep was investigated in 25 sheep. Two constant branches were identified by dissection and angiography, and the cutaneous areas they supply identified. The arterial system was put to two separate experimental uses successfully.  相似文献   

20.
1. The effects of 90 min continuous treadmill exercise on the plasma-to-ovary transfer of 14C-labelled triglycerides in laying hens were examined. 2. Exercised birds showed a 4-fold increase in plasma free fatty acid concentration, a 15% decrease in plasma glucose concentration and unchanged plasma triglyceride concentration compared with resting controls. The mean plasma-to-ovary triglyceride transfer rate was approximately halved by exercise. 3. The surface area-specific triglyceride transfer rate was greatest for oocytes weighing 0.25-1.5 g and decreased with increasing oocyte size. The lowest rates were in the small (less than 0.25 g) white oocytes. This pattern was largely unaffected by exercise. 4. Factors that might be responsible for the reduction in triglyceride transfer into the oocytes during exercise include hormonal effects on the permeability of the oocyte envelope, increased competition for plasma lipids by the working muscles and reduced blood flow to the ovary, as a result of the release of vasoconstrictors.  相似文献   

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