摘要:

A method is described which allows a clear demonstration of capillaries and muscle fibers in the heart and skeletal muscle of experimental animals. The fluorescent dyes fluorescein isothiocyanate (FITC) and lissamine rhodamine B 200 (RB 200) were conjugated with a protein of high (γ-globulin) and low (myoglobin) molecular weight, respectively, and were intravitally injected into the vascular system of rats. FITC globulin distributes itself in the intravasal space and RB 200 myoglobin in the extracellular. In histological sections the capillary lumina and the borderlines of the muscular fibers can be clearly identified and quantitatively evaluated because of the selective fluorescence in the respective structures

ISSN:1422-6405    

DOI:10.1159/000145753

出版商:S. Karger AG    

年代:1983

数据来源: Karger

摘要:

Medico-legal data are presented on 995 child deaths, 361 girls and 634 boys aged 0–18 years, whose brains were weighed at the time of autopsy using a standardized weighing technique (the brains were weighed before fixation, immediately after entire removal; the medulla oblongata was divided in the foramen magnum). From the results it appears that the brain weights are greater than those reported in a previously published series. This may be ascribed to a higher degree of oedema and a shorter duration of illness, or an absence of illness; another explanation may be related to a difference in origin. It should be remembered that post-mortem brain weights exceed the ante-mortem weights by up to 9%. The greater part of brain growth is completed by the end of the 2nd year of life, and thereafter the brain weight in girls is on the average a little lower than that in boys. No significant differences in brain weights are found in the various groups of causes of death; the brain weights in the group of sudden, unexpected infant deaths especially do not deviate from those in the other group

ISSN:1422-6405    

DOI:10.1159/000145754

出版商:S. Karger AG    

年代:1983

数据来源: Karger

摘要:

A semiquantitative scanning electron microscopic method for analysis of the articular cartilage surface morphology was developed. The method was based on a survey of large picture montages (ca. 70 × 100 cm) and classification of the cartilage surface changes at three levels. Computer technique was utilized in the analysis. The method ensured numerical expression and statistical treatment of the results. With this method we investigated the effects of physical exercise and immobilization on the articular cartilage of rabbit patella

ISSN:1422-6405    

DOI:10.1159/000145755

出版商:S. Karger AG    

年代:1983

数据来源: Karger

摘要:

The contribution deals with the histoenzymological makeup of telencephalon and diencephalon of a microchiropteran bat which is considered to have a primitive type of brain. Three esterases, namely acetylcholinesterase (AChE), butyrylcholineesterase (BChE) and nonspecific esterase (NSE), have been studied. In comparison with other mammalian brains the telencephalon and diencephalon of the bat demonstrate a high concentration of enzyme, especially in the nucleus caudatus and putamen, stria medullaris and the nuclei of the thalamus. AChE concentration is higher in neurons, while BChE is seen in almost all fibrous areas of the telencephalon and diencephalon. NSE activity is prominent in neurons and neuropil of neocortex, thalamus and hypothalamus. All the above data indicate that the brain of echolocating microchiropteran bats is metabolically much more active than that of other mammals. This is specifically true of the auditory system which is considerably specialized in these animals; this is also confirmed by the present histoenzymological study.

ISSN:1422-6405    

DOI:10.1159/000145756

出版商:S. Karger AG    

年代:1983

数据来源: Karger

摘要:

Thyroid lobes of the newborn opossum consist of small epithelial cords or plates, the constitutent cells of which are joined by tight junctions and surround a minute lumen that courses throughout the length of each cord. Occasional cells, not directly associated with the lumina of the cords, show central nuclei and clusters of small electron-dense granules: these may represent parafollicular cells at an early state of development. By the end of the 1st week after birth, parafollicular cells are well established and appear as groups between the epithelial cords and as scattered individual cells within the cords. Growth of the thyroid occurs as the cords continue to elongate and branch. 11 days after birth, thyroid development in the opossum corresponds morphologically to that of eutherians just prior to birth. Primary follicles are present near the periphery of the thyroid lobes, having formed from evaginations of the epithelial cords. There is evidence of synthetic activity by the epithelial cells and colloid is present. Secondary follicles form as a result of evaginations from the epithelium of the primary follicles. At the end of the 2nd postnatal week, epithelial cords are no longer a prominent feature of the opossum thyroid, and the organ is now characterized by numerous, small colloid-filled follicles. As development progresses, the follicles increase in size and number and, by 35 days after birth, the thyroid shows adult features.

ISSN:1422-6405    

DOI:10.1159/000145757

出版商:S. Karger AG    

年代:1983

数据来源: Karger

摘要:

Pregnant Swiss albino mice were whole-body exposed to 250, 150 and 50 R gamma-radiation from 60Co in the presence or absence of 2-mercaptopropionylglycine during selective organogenesis and fetal growth periods (days 11.25 and 14.25, 16.25 and 18.25 after conception, respectively). Both the protected and nonprotected pregnant females of 11.25-day gestation showed complete resorption of embryos irradiated with 250 R. With 150 R, in absence of the drug, 11.25-day gestating females showed partial resorption (76.10%). The percentage of parturition improved in the drug-treated females. Nonprotected females irradiated with 50 R showed slight resorption, while drug-treated females had normal parturition. Females irradiated during the fetal growth period showed no resorption. Also, no significant alteration in litter size and sex ratio of the newborn animals was noticed when irradiated during this period, both in the control and the experimental groups. Mortality of the young was higher in nonprotected animals as compared to the protected ones.

ISSN:1422-6405    

DOI:10.1159/000145758

出版商:S. Karger AG    

年代:1983

数据来源: Karger

摘要:

The changes occurrring in the endocrine pancreas of the rat after partial pancreatectomy were studied morphometrically. Pancreatic adaptation to the functional deprivation of 75% of the endocrine tissue is characterized by a hyperplastic process with increased cell numbers and increased size and volume of the islets.

ISSN:1422-6405    

DOI:10.1159/000145759

出版商:S. Karger AG    

年代:1983

数据来源: Karger

摘要:

The distance between mitochondria and the nearest plasma membrane was measured in actively secreting and nonsecreting exocrine glands in order to determine the effect of the secretory mechanism upon mitochondrial distribution. The greatest accumulation of mitochondria was at 0.6 µm from the plasma membrane. No difference was noted in mitochondrial distribution of actively secreting, untreated and atropine-treated animals. There was also no difference in mitochondrial distribution of lacrimal and parotid acinar cells. The possible physiological significance of this observation is discussed

ISSN:1422-6405    

DOI:10.1159/000145760

出版商:S. Karger AG    

年代:1983

数据来源: Karger

摘要:

The structural alterations produced by transection in striated fibers of cremaster muscle are studied with light and electron microscopes. Diffusion of procion yellow and procion black, which are extracellular space markers, is observed after incubating the transected fibers in the presence or in the absence of Ca++ for 1 h. Cytoplasm at the injured end is always separated from the extracellular space by the sarcolemmal membrane. No outflow of cytoplasmic structures can be seen with light or electron microscopes. The zone of muscle fiber adjacent to the transection is generally dilated. It is occupied by a meshwork of 7-nm-thick filaments. No normal myofibrils are present. The diffusion of procion markers comes to an end within 1 h after the lesion if the fiber is incubated in normal Krebs’ solution. In this period of time they penetrate 250–350 µm inside the fibers. When the transected fibers are incubated in a Ca++ -free solution, procion dyes penetrate about 1 mm. This distance increases in the following 3 h. Diaphragm muscle fibers are used as controls. In these fibers the free penetration of the markers by the injured end is not impeded by Ca++ . These results are in accordance with the calcium-dependent recuperation of the membrane potential 1 h after the transection in cremaster muscle fibers, and with the absence of this recuperation in the diaphragm. It is proposed that the closure of the sarcolemmal membrane creates the diffusion barrier blocking the penetration of markers and ions, allowing the recuperation of membrane poten

ISSN:1422-6405    

DOI:10.1159/000145761

出版商:S. Karger AG    

年代:1983

数据来源: Karger

摘要:

In experimental jejunal obstruction produced in cats, the neurones of the intermediate gray column of the cord showed bilateral intranuclear inclusions. They were also seen when hypertrophy and hyperplasia, produced in various elements of the bowel wall, were prevented by large doses of atropine. The latter observation implied that the afferent autonomic nerve supply is involved in the production of these unusual structures. The inclusion bodies were extremely rare or absent in control animals. In order to see whether these bodies occurred by chance even though they are regularly produced in the above-mentioned area, an effort was made to see whether they would appear unilaterally following stimulation of a unilateral afferent nerve. This was done by ligation and severance of the right common carotid artery below its bifurcation with or without severing its accompanying vagal trunk. Removal of the pulsatile blood supply to the carotid sinus and carotid body has long been known to produce afferent action potentials in the glossopharyngeal and vagus nerves. Within 6 h many neurones in the middle half of the ipsilateral nucleus of the tractus solitarius showed the inclusions. The cephalic end of this nucleus showed no inclusions. At the level of the obex the inclusions were present bilaterally. The inclusions also appeared in numerous other areas of the brain, brain stem and cervical cord in bilateral fashion. They were found in neurones of the neurohyphysis as well as in the cingulate gyrus. Their widespread but focal distribution corresponds to numerous areas of the cord and brain in which physiologists have produced striking effects with electric probing and stimulation. The inclusion bodies are at present conceived as representing the neuronal nuclear response to an afferent stimulus which causes an increase in the metabolic activity controlled by the nucleus.

ISSN:1422-6405    

DOI:10.1159/000145762

出版商:S. Karger AG    

年代:1983

数据来源: Karger