Hyaluronate inhibition of chondrogenesis: antagonism of thyroxine, growth hormone, and calcitonin

The formation of cartilage-like aggregates in high-density stationary cultures of trypsinized chick embryo precartilage cells is blocked by low concentrations of hyaluronate. Thyroxine (and triiodothyronine), growth hormone, calcitonin, and adenosine 3',5'-monophosphate prevented this inhibition by hyaluronate, whereas other hormones tested did not.     

Angiogenesis induced by degradation products of hyaluronic acid

Partial degradation products of sodium hyaluronate produced by the action of testicular hyaluronidase induced an angiogenic response (formation of new blood vessels) on the chick chorioallantoic membrane. Neither macromolecular hyaluronate nor exhaustively digested material had any angiogenic potential. Fractionation of the digestion products established that the activity was restricted to hyaluronate fragments between 4 and 25 disaccharides in length.     

Galactose toxicity in the chick: hyperosmolality

Galactose-fed chicks have been found to develop severe hyperosmolar dehydration. Although biochemical abnormalities have been observed in the brain of the galactose-toxic chick, the observed physiologic alteration of serum osmolality could be the major factor responsible for the galactose toxicity syndrome in the chick.     

Assembly of chick brain tubulin onto isolated basal bodies of Chlamydomonas reinhardi

Basal bodies isolated from Chlamydomonas reinhardi will serve as initiation centers for the assembly of chick brain microtubule protein subunits (tubulin) into microtubules. The rate of microtubule assembly is tubulin-concentration dependent; this assembly occurs onto both distal and proximal ends of the basal body mnicrotubules, with distal assembly greatly favored. In vitro assembly of brain tubulin also occurs onto the mid-lateral aspects of the basal bodies, presumably onto the fiber connecting the two basal bodies.     

Competent chick ectoderm: nonspecific response to RNA

Presumptive chick neuroectoderm responds to RNA from brain and heart by forming neural tubes, but it does not respond to liver RNA. This dif ferential response can be correlated with the presence of Folin-positive material in those RNA preparations which elicit the formation of neural structures.     

Testosterone concentration in the male chick brain: an autoradiographic survey

Differential uptake of [(3)H]testosterone in male chick brain was found in periventricular areas of preoptic-hypothalamic continuum. Concentration of silver grains for all decapitation periods was especially high in the medial preoptic area, particularly the nucleus praeopticus paraventricularis magnocellularis. Distribution of testosterone-sensitive cells is in agreement with studies showing neuroanatomical control of reproductive behavior by the avian forebrain.     

雏鸡对饲粮硒含量的反应和蛋氨酸对其反应的影响

采用缺硒低蛋氨酸的玉米——豆饼型基础饲粮添加或不添加硒和(或)DL-蛋氨酸三次重复试验研究了雏鸡对饲粮硒含量的反应和蛋氨酸对其反应的影响.试验阐述了组织硒含量、全血谷胱甘肽过氧化物酶活力与饲粮硒含量之间的关系.观察了雏鸡在不同水平硒和蛋氨酸饲粮下的生产表现,测定了蛋氨酸对雏鸡缺硒疾病、组织硒含量和全血谷胱甘肽过氧化物酶活力的影响.试验结果为使微量元素硒在动物营养中合理应用提供了依据.     

Secretory activity and oncogenicity of a cell line (MDCK) derived from canine kidney

A cell line (MDCK) of dog kidney origin grows on a glass surface as a mosaic of epithelium with many multicellular hemispherical vesicles. The cells lining the blisters actively secrete into the cyst cavities. Suspensions of these cells injected intravenously in the chick embryo produce brain metastases resembling adenocarcinoma.     

Effect of dietary fats on fatty acid composition of human erythrocytes and chick cerebella

Through gas-liquid chromatography it can be shown that increasing the ingestion of linoleic acid-containing fats increases the deposition of linoleic acid in erythrocytes and in brain tissue. Such changes are probably causally related to the tocopherol requirement, the incidence of chick encephalomalacia, and the peroxide hemolysis test. Whether similar mechanisms are involved in the ability of unsaturated oils to lower serum cholesterol levels remains to be determined.     

猪伪狂犬病病毒的分离鉴定

从天津市郊县某猪场发病仔猪脑中分离到一株病毒。该病毒接种鸡胚绒毛尿囊膜有白色的痘斑出现,接种PK-15和BHK-21细胞出现典型的细胞病变,毒价(TCID50)为10-6/mL,且能被PRV阳性血清中和;将病毒给家兔注射后出现典型的伪狂犬病症状并导致死亡。通过上述试验结果证明,该分离毒株为伪狂犬病毒。     

Generalized potential of adult neural stem cells

The differentiation potential of stem cells in tissues of the adult has been thought to be limited to cell lineages present in the organ from which they were derived, but there is evidence that some stem cells may have a broader differentiation repertoire. We show here that neural stem cells from the adult mouse brain can contribute to the formation of chimeric chick and mouse embryos and give rise to cells of all germ layers. This demonstrates that an adult neural stem cell has a very broad developmental capacity and may potentially be used to generate a variety of cell types for transplantation in different diseases.     

Interferon: production by chick erythrocytes activated by cell fusion

In the presence of Sendai virus inactivated with ultraviolet light, nucleated chick erythrocytes can be fused with several types of human cells to form heterokaryons. Although chick erythrocytes alone cannot be stimulated by Sendai virus to produce interferon, fusion with a human cell (AH-1) which itself may produce human interferon results in heterokaryons in which the erythrocyte genome is activated and chick interferon is produced. When nucleated chick erythrocytes are fused with another type of human cell (HeLa clone S-3) which does not produce human interferon when stimulated, no chick interferon is detectable, despite morphologic changes suggestive of activation of the erythrocyte nuclei.     

Inductive interactions between human dermis and chick chorionic epithelium

In a study of specificity in mesenchymal-epithelial interactions, human embryonic dermis has been recombined with chick chorionic epithelium and cultured for 7 days on a host chick chorioallantoic membrane. Dermis from the sole of the foot or palm of the hand induces chick chorionic epithelium to form an epidermis that resembles chick rather than human epidermis. Chick epithelium, though it has the capacity to respond to a human dermal stimulus, is limited to forming chick-type tissue. The human dermis was modified in its turn by culture in combination with chick epithelium.     

中药封包配合臭氧、玻璃酸钠治疗早期创伤性踝关节炎的临床观察

目的 观察中药封包外敷联合臭氧、玻璃酸钠关节腔内注射治疗早期踝关节创伤性关节炎的临床疗效。方法 收集创伤性踝关节炎患者50例,随机分为对照组和治疗组,对照组25例行单纯玻璃酸钠关节腔内注射治疗,治疗组25例行玻璃酸钠、臭氧关节腔注射,并予中药封包外敷治疗,根据治疗前、治疗后1周、5周及治疗后6个月视觉模拟评分（VAS）,踝关节功能Mazur评分及临床有效率对比评估两组治疗效果。结果 治疗后,两组各时间点的VAS评分较治疗前均降低,且治疗组降低幅度均大于对照组（P<0.05）;在治疗后各时间点,两组Mazur评分均比治疗前高,且治疗组提升幅度大于对照组（P<0.05）;治疗后治疗组临床有效率96%高于对照组88%（P<0.05）;两组均未观察到明显的不良反应。结论 中药封包配合踝关节腔内注射玻璃酸钠、臭氧治疗和单纯玻璃酸钠踝关节注射治疗对早期踝关节创伤性关节炎均可取得一定疗效,且前者治疗踝关节创伤性关节炎能更好地改善早期症状及巩固远期疗效。     

Progesterone-dependent messenger RNA: heterospecific activity in vivo

The action of progesterone in mediating the synthesis of avidin by the chick oviduct can be simulated by the intraoviductal instillation of nitrocellulose-trapped RNA from hormonally prepared chick or pigeon oviduct. Similarly, the pigeon oviduct synthesizes avidin in response to chick oviduct RNA. Thus, a heterospecific transfer of hormonal stimulation, through the transfer of progesterone-induced RNA, is demonstrated. The biological activity is lost after digestion by pancreatic ribonuclease. The 50-fold purification achieved by nitrocellulose chromatography of the total RNA preparation suggests that the activity resides in a messenger RNA fraction.     

Overgrowth stimulating factor released from Rous sarcoma cells

An assay is described for a nonzviral factor from the medium of Rous sarcoma cells which stimulates rapid and sustained cellular overgrawth in crowded chick embryo cultures. The factor is nondialyzable and thermnolabile and is released in large amounts several days after the first visible transformation of newly infected chick embryo cells.     

肉种鸡公鸡腿病的诊治

肉种鸡在饲养过程中腿病发生率很高,公鸡尤为明显和敏感,对以后种蛋的生产影响较大,严重影响其生产性能,使鸡场的经济效益严重受损。本文就一例肉种鸡公鸡发生腿病进行诊治,诊断结果为细菌感染,使用敏感抗生素阿莫西林治疗有效。     

地巴唑、左旋咪唑对雏鸡新城疫疫苗和巴氏杆菌灭活苗免疫应答的影响

试验在对雏鸡免疫接种新城疫疫苗和巴氏杆菌灭活苗的同时,用免疫调节剂地巴唑或左旋咪唑,观察其对抗体应答作用。结果表明:免疫调节剂能增进机体对新城疫、巴氏杆菌的抗体滴度,如有干扰素诱生剂协同,能进一步提高抗体水平。     

不同营养水平和环境温度对雏鸡随意采食量和饮水量的影响

对320只肉用雏鸡在不同温度和不同营养水平下的随意采食量、随意饮水量的观察表明：能量水平高低（基他营养水平基本衡定）直接影响雏鸡的随意采食量。布蛋白质水平的高低对随意采食量没有明显的影响，但蛋白质或能量水平的高低均显著影响雏鸡随意饮水量（P＜0．01）。同时采食量与饮水量存在正相关，这种相关不受营养水平高低的影响，还讨论了随意食量、随意饮水量随日龄和环境温度变化的规律以及与雏鸡体重的回归方程。     

新城疫活疫苗HB92克隆株的筛选、纯化与细胞培养特性观察

将引进的新城疫V4无毒耐热毒株连续用鸡胚传代.每次挑选48～96 h有明显病变的死亡鸡胚,取其尿囊液毒于-20℃保存,观察V4毒株对鸡胚毒力的病理变化.结果显示,经过20代次的鸡胚毒力筛选.V4毒株对鸡胚的致死率从小于10%上升至20%以上,接种后120 h的活胚有明显地萎缩症状.将鸡胚20代次以上筛选的V4病毒液在鸡胚成纤维细胞上传代培养,并进行蚀斑筛选纯化病毒,直到第5代才出现明显地细胞病变.使用二层琼脂进行病毒的蚀斑分析,第二层琼脂糖在第一层凝固后72 h覆盖,8 h后NDV鸡胚成纤维细胞适应株的蚀斑出现.蚀斑大小直径在1～2 mm变化.通过对NDV V4鸡胚毒力筛选和蚀斑纯化.获得了一株蚀斑克隆株(NDV HB92).