摘要:

AbstractA comparison of results of measuring supraoptic neuron activity was made in normal and in dehydrated rats by the following methods; (1) Measuring the nucleolar diameter of the neurons with a filar micrometer, with an image splitting eyepiece and, with the latter instrument, using the “comparative technique”—all three methods yielded statistically significant differences. (2) Measuring the concentration of cresyl violet in the nucleoli with a microspectrophotometer—a statistically significant difference was found. Also included for comparison were the results of a previous experiment in which the ribonucleic acid and succinic dehydrogenase content of the supraoptic nucleus was measured with a spectrophotometer following chemical extraction. The RNA was found to increase significantly but not the succinic dehydrogenase. Of the methods used for measuring nucleolar diameters the “comparative technique” appeared to be the most rapid from the practica

ISSN:0003-276X    

DOI:10.1002/ar.1091520302

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1965

数据来源: WILEY

摘要:

AbstractIn the heart ofPasserthe specialized conducting tissue develops earlier than the nervous elements. The sinuatrial and the atrioventricular nodes appear simultaneously at the 15 mm stage and the atrioventricular bundle at the 23 mm stage. During development the sinuatrial node shifts its position due to the gradual absorption of the sinus venosus into the right atrium. The caudal end of the interatrial septum is enlarged to accomodate the compound atrioventricular node. In the adult bird the bundle branches extend through the atrioventricular valves of their sides and reach the other wall of the ventricular cavity. Among the specialized tissues, the sinuatrial region is the first to receive the nerve supply. The atrioventricular nodal and bundle regions are innervated by the ganglia present at the atrioventricular sulcus. The ganglionic cells are bipolar or multipolar. The nerve fibers terminate in “end‐bulbs.” Only the atrioventricular node shows a few fine nerve fibers within its substance. No direct nerve connection is present between the nodes and the bundle. It seems that the nervous elements present in the regions of the specialized tissues are concerned only with the control of the activity of these struc

ISSN:0003-276X    

DOI:10.1002/ar.1091520303

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1965

数据来源: WILEY

摘要:

AbstractDuring a routine dissection, an anomalous arrangement of the flexor musculature of the hand was discovered. This bilateral anomaly included a deficient superficialis tendon to the index finger and the little finger and an absence of the fourth lumbrical muscles. The deficiency of the sueperficialis tendons to the index fingers was compensated for, however, by an anomalous muscle in each palm.The literature was searched both for related cases and for embryologic and phylogenetic background with which to explain the presence of this unusual combination of anomalies.

ISSN:0003-276X    

DOI:10.1002/ar.1091520304

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1965

数据来源: WILEY

摘要:

AbstractThe circle of Willis was dissected in 75 Macaca mulatta monkeys, and the anatomy is described and compared with several series of human specimens. The principal difference between monkey and man is the presence of a single distal anterior cerebral artery in the former, and the most common anomaly in the moneky is an anterior communicating artery proximal to the junction of the anterior cerebral arteries.A large vessel joining the internal carotid arteries and an accessory branch of the anterior cerebral artery, probably communicating with the external carotid circulation, were found in a small number of our specimens. In man the posterior communicating is significantly reduced in diameter far more frequently than the anterior communicating artery, whereas the reverse situation obtains in the monkey.In general, the intracranial distribution of blood in the moneky is the same as in man, because the similarities in the normal anatomy and variations i the circle of Willis outweight their differences. However, physiological data on collateral cerebral circulation will be more meaningful when it is based on the arterial anatomy in each preparation.

ISSN:0003-276X    

DOI:10.1002/ar.1091520305

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1965

数据来源: WILEY

摘要:

AbstractFine structural localization of enzymes hydrolyzing nucleoside phosphates in the rat adrenal cortex has been determined, and the selective inhibition of those enzymes exhibiting intracellular localization has been effected. Glutaraldehyde‐fixed adrenocortical tissue was incubated in a medium which contained a nucleoside mono‐, di‐ or triphosphate of adenosine, inosine, guanosine, or cytidine as substrate. Intracellular enzymatic activity was exhibited when one of three nucleoside phosphate substrates was employed. When IDP was used, final product of enzymatic activity was found on membranes of the endoplasmic reticulum, Golgi cisternae and intramitochondrial microvesicles. Final product was localized on the membranes of the endoplasmic reticulum and certain mitochondria when ITP was used. With GTP as substrate, activity was primarily localized on mitochondrial microvesicles and agranular endoplasmic reticulum, with no Golgi involvement noted.The phosphatases for which intracellular localization was determined exhibited four different sites of activity: (a) agranular endoplasmic reticulum, (b) microvesicles within mitochondria, (c) nuclear membrane, and (d) subendothelial and/or intercellular spaces with occasional involvement of the plasma membrane. When nicotinamide was added to the incubation media, intracellular phosphatase activity was inhibited. Extracellular enzymatic activity was unaffected by nicotinamide. The possible mode of action of nicotinamide in enhancing steroidogenesis and inhibiting intracellular phosphatase activity is disc

ISSN:0003-276X    

DOI:10.1002/ar.1091520306

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1965

数据来源: WILEY

摘要:

AbstractThe placental barrier of the mouse was examined by light and electron microscopy and found to be of the hemo‐chorial and not of the hemo‐endothelial type, as had been previously suggested. The suspected immunological function of the trophoblast is briefly reviewed, and attention drawn to the recent reclassification of the shrew place

ISSN:0003-276X    

DOI:10.1002/ar.1091520307

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1965

数据来源: WILEY

摘要:

AbstractDorsal roots from adult rabbits prepared by a freeze‐substitution technique and studied by electron microscopy have been compared with those obtained by standard fixation with OsO4. The essential features of myelinated and nonmyelinated fibers and their associated Schwann cells are similar in appearance after both types of fixation. There are, however, slight differences. The extracellular clefts between the nonmyelinated axons and their associated Schwann cells are wider in freeze‐substituted roots (200 to 250 Å versus 100 to 150 Å). The major dense lines in the myelin sheath are wider (45 to 55 Å versus about 30 Å) and their radial repeat period is larger (145 to 155 Å versus 100 to 120 Å) in freeze—substituted material than in routinely f

ISSN:0003-276X    

DOI:10.1002/ar.1091520308

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1965

数据来源: WILEY

摘要:

AbstractA human egg in the pronuclear stage was recovered by flushing the excised oviduct that had been removed along with the uterus. The hysterectomy and right salpingectomy were performed on day 16 of the patient's menstrual cycle. The egg was examined first in the fresh state and revealed two pronuclei, a granular zona pellucida, and corona cell processes traversing the zona pellucida. The egg was subsequently fixed and stained revealing further details of the pronuclei, and the tail of the fertilizing spermatozoon lying over one of the pronuclei.The age of the egg was estimated as being 3 to 50 hours post ovulation time.

ISSN:0003-276X    

DOI:10.1002/ar.1091520309

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1965

数据来源: WILEY

摘要:

AbstractThe estrous cycles of 34 Dorset Horn ewes were observed during the spring and summer in East Anglia. The majority of sheep (22 out of 34) came in heat fairly regularly. In 26 out of 37 estrous cycles the duration was between 14 and 25 days. Laparotomy performed soon after estrus did not prolong the subsequent estrous cycle in the majority of animals. Failure of ovulation following estrus was not observed; the observations were made either at laparotomy or at autopsy. The rate of ovulation was 1.55 per cycle as assessed by counting the number of corporalutea in the ovary. The time of ovulation was estimated at about 30 to 40 hours after the onset of estrus.Following deposition of semen into the Fallopian tubes of nine ewes, either before or soon after ovulation, five eggs were recovered but none of these was found to be fertilized. Following intra‐cervical insemination or mating 21 fertilized eggs, at different stages of division, were found in 11 out of 29 ewes. In 13 ewes out of 26 which were examined 5–17 days after mating 15 normal embryos were found. Photomicrographs of early sheep embryos are presented and the low fertility of sheep in summer is discus

ISSN:0003-276X    

DOI:10.1002/ar.1091520310

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1965

数据来源: WILEY

摘要:

AbstractThe epidermis of the potto, which normally contains no DOPA‐reactive melanotic melanocytes, supports a population of large dendritic cells which are specifically reactive for alkaline phosphatase. After irradiation of the skin with ultraviolet light, these same dendritic cells become DOPA positive and produce visible melanin. These results give further evidence that the alkaline phosphatase‐reactive dendritic cells are part of a unique system of epidermal melanocy

ISSN:0003-276X    

DOI:10.1002/ar.1091520311

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1965

数据来源: WILEY