摘要:

AbstractBy means of two sawcuts the middle ear can be exposed quickly. The first cut in a coronal plane through the suprameatal triangle usually bissects the tympanic antrum. After removal of the tegmen tympani and the incus, the second sawcut is made in an antero posterior direction; the blade of the saw descends into the gap left by the removal of the incus. Thus the middle ear is split with the tympanic membrane on one fragment and the medial wall of the middle ear on the other. This method has proved to be rapid and effective and superior to the traditional method of nibbling bone to expose the antrum and middle ear.

ISSN:0003-276X    

DOI:10.1002/ar.1091510402

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

年代:1965

数据来源: WILEY

摘要:

AbstractThe development of bile canaliculi and the sequence of appearacne of iculi appear on about the thirteenth embryonic day in close association with linear attachment zones between adjacent hepatic cells. These canaliculi are formed by only two apposed cell surfaces and the configuration of a central biliary lumen bounded by 4– contiguous cells described classically as typical for developing mammalian liver is not apparent until day 16 or 17. The enlarged biliary spaces apparently arise as separate vesicles or saccules which subsequently elongate into tubules and interconnect. Evidence obtained in this study supports the concept that terminal bile ductules develop by direct transformation of tubular channels lined by hepatic cells under the influence of periportal connective tissue. Pericanalicular bodies develop in association with an hypertrophied Golgi zone. The sequence of appearance is: multivesicular bodies, microbodies, typical lysosomes. There is no evidence from this study that microbodies are related to differentiating mitochondria but the chronology of appearance suggests a close relationship to lysosome

ISSN:0003-276X    

DOI:10.1002/ar.1091510403

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

年代:1965

数据来源: WILEY

摘要:

AbstractPulmonary vessels of excised rabbit lungs were injected with a suspension of barium sulfate in gelatin. Slices 50 μ thick were radiographed at 5 kv and 2 ma using high resolution spectroscopic plates. When these plates were viewed through a microscope, pulmonary arterioles, venules and capillaries were identified. Arterioles show relatively regular branching at right angles. The capillary bed fills from short (10–20 μ long), thin (10–15 μ diameter) precapillaries arising at right angles from arterioles. The alveolar capillary network freely communicates with networks of adjacent alveoli. Several capillaries draining alveolar nets usually join forming a vessel which is broader at its origin than its insertion into a venule. These vessels, designated collecting venules join the venule at acute angler Clear differentiation of small venous vessels from adjacent small arterial vessels is possible. The capillary network between an arteriole and venule appears to span at least two a

ISSN:0003-276X    

DOI:10.1002/ar.1091510404

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

年代:1965

数据来源: WILEY

摘要:

AbstractIn this study, experiments are described in which part cr all of the occipital somites were removed from chick embryos of 8 to 25 somites. The embryos were reincubated and sacrificed 6 to 9 days after the operation. Adequate extirpations of somites 2 through 6 resulted in absence or depletion of one or more of the hypoglossal muscles, thus demonstrating their somtic origin from these levels. Somite 1 disappears early and does not make a contribution to the hypoglossal muscles. The optimal stages for operation are between 8 to 15 somites.

ISSN:0003-276X    

DOI:10.1002/ar.1091510405

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

年代:1965

数据来源: WILEY

摘要:

AbstractA study of anterior femoral curvature was carried out on a total of 874 White, Negro, Eskimo, and American Indian femora. Variations in race, sex, and side, as well as ontogenetic changes, have been investigated. The results indicate that distinct differences in the amount and location of femoral curvature exist. Sex and side differences were generally found to be small, race differences however, in both sexes, are striking. When used with other established criteria, these data on femora will be of value in identifying skeletons of certain racial groups.It seems likely that inherent racial differences provide the substrate, as well as set the developmental limitations, for any modifications which may be imposed by function. The basic curvature may be modified or maintained by variations in the inherited physical properties of the femur. The response of these physical properties to the demands of differing extrinsic influences must also be of importance in determining the amount and location of femoral curvature.

ISSN:0003-276X    

DOI:10.1002/ar.1091510406

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

年代:1965

数据来源: WILEY

摘要:

AbstractEvidence is presented that the hemochorial placenta of the ninebanded armadillo,Dasypus novemcinctus, is permeable to trypan blue when this dye is injected subcutaneously into the mother during the postimplantation period. This permeability appears to be related to a time‐dependent active process or is associated with the maturation of the fetal reticulo‐endothelial system. Spectrophotometric analysis of serum proteins revealed alterations in the dye‐injected mothers as well as in thalidomide‐treated animals as compared to untreated controls. While it is difficult at present to estimate the stage of pregnancy under teratogenic study, it is felt that this unusual experimental animal warrants further study with other teratogenic

ISSN:0003-276X    

DOI:10.1002/ar.1091510407

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

年代:1965

数据来源: WILEY

摘要:

AbstractA series of 15 rabbits had multiple intercostal clip electrodes implanted in the diaphragm and quadratus lumborum at open operation.Leads from the electrodes were passed to the back of the animals and soldered to a junction band. Simultaneous recordings of electromyographic activity and spirometry were made following recovery.The study revealed that the quadratus lumborum, acting simultaneously with the diaphragm, is an effective inspiratory muscle stabilizing the twelfth rib, converting it into a fixed point from which the diaphragm act. Very possibly the action of the quadratus pulls down the lower rib helping to increase the costo‐diaphragmatic recess. Like the sternal, crural and costal portions of the diaphragm, the quadratus exerts a braking action to oppose the normal elastic recoil of the lungs during expiratio

ISSN:0003-276X    

DOI:10.1002/ar.1091510408

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

年代:1965

数据来源: WILEY

摘要:

AbstractA group of autonomic fibers cross the midline over the ventral surface of the cervix of the uterus in the female rat and around the dorsal edge of the prostate and between the spermatic ducts in the male. There is no clear explanation for these decussations.

ISSN:0003-276X    

DOI:10.1002/ar.1091510409

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

年代:1965

数据来源: WILEY

摘要:

AbstractIn spite of a renewed interest in the rectal (salt‐secreting) gland of the spiny dogfish,Squalus acanthias, the morphology of the stratified epithelium lining the central lumen and large ducts of this gland has been mentioned only briefly. The fluid removed from the duct of the rectal gland has been shown by Burger and Hess ('60a, b) and Burger ('62) to be a concentrated sodium chloride solution. The function of the stratified epithelium in the elaboration of this fluid is unknown. It is of interest to know if the stratified epithelium has morphological specializations which might suggest its function.The stratified epithelium of the central canal consists of surface cells, intermediate cells, and basal cells. Four types of surface cells can be distinguished: granular cells, mucous cells, flask‐shaped cells, and cells with large mitochondria. The intermediate cells form a loose network. In the large extracellular spaces between the intermediate cells, free cells presumably of blood origin, can be seen. The basal cells lie on a basement membrane. There is a structural resemblance of the epithelium to that of the toad blad

ISSN:0003-276X    

DOI:10.1002/ar.1091510410

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

年代:1965

数据来源: WILEY

ISSN:0003-276X    

DOI:10.1002/ar.1091510411

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

年代:1965

数据来源: WILEY