摘要:

AbstractA case of double superior venae cavae with bilaterally symmetrical azygos veins is recorded for a 45 year old Caucasian male cadaver with no history of cardiovascular disorder. Death was reported as resulting from carcinoma of abominal viscera with extensive metastases.A review of the literature since 1887 indicates that this is an addition to 216 cases of double superior venae cavae and seven cases of double azygos veins previously reported in cadavers.A typical left brachiocephalic vein was absent. The anomalous vena cava, formed by union of left internal jugular and left subclavian veins behind the sternoclavicular joint, coursed vertically through the superior mediastinum, continued through the atrioventricular sulcus and opened into the right atrium near the orifice of the inferior vena cava. It was almost completely symmetrical with the right and received a complete azygos vein.The anomaly is explained as (a) failure of the precardinal anastomosis to form, (2) persistence of the entire left anterior and common cardinal veins and left horn of the sinus venosus, and (3) persistence of the proximal part of the left posterior cardinal which with the left supracardinal forms the left azygos vein. Morphological and clinical significances of the anomaly are discussed.

ISSN:0003-276X    

DOI:10.1002/ar.1091510102

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

年代:1965

数据来源: WILEY

摘要:

AbstractBecause of the inhibitory effect of testosterone on lympho‐epithelial nodule formation in the bursa of Fabricius, possibly through the suppression of alkaline phosphatase activity of the surrounding mesenchyme, there appears the possibility of a comparable inhibitory effect on the thymus.1. A single dose of one tenth milliliter (2.5 mg) of testosterone propionate in sesame oil (Schering) was injected into chick eggs between the first and fifth days of incubation, i.e., before and during the time of differentiation of the thymus from the epithelial primordia and before the appearance of lymphoblasts. The thymuses of 195 chicks including 50 controls were examined after 18 days of incubation; grossly and microscopically the thymus gland was relatively unaffected in all but a few chicks.Because the thymus appeared unaffected by testosterone as opposed to its complete inhibitory effect on the bursa of Fabricius; and because of the apparent relationship of testosterone‐labile alkaline phosphatase to epithelial nodule formation in the bursa, further investigations were carried out on thymic differentiation and the possible role, if any, of alkaline phosphatase activity in the surrounding mesenchyme.2. Chick embryos between 5–10 days of incubation were fixed in 80% ethanol or absolute acetone, embedded in paraffin, serially sectioned and exposed to either Gomori's glycerophosphate or Burstone's naphthol AS‐MX phosphate procedures for alkaline phosphatase activity. The mesenchyme surrounding the developing thymus showed either a negative or a negligible reaction for alkaline phosphatase activity following these procedures. In contrast, the thymic primordium did exhibit slight phosphatase activity which appeared to be localized in the reticular‐epithelial cells.The difference in demonstrable alkaline phosphatase activity of the capsule of the thymus and of the subepithelial mesenchyme of the bursa of Fabricius suggests a fundamental difference in the differentiation of the two organs in the embryo

ISSN:0003-276X    

DOI:10.1002/ar.1091510103

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

年代:1965

数据来源: WILEY

摘要:

AbstractThymocytes of young rats were studied with the electron microscope to provide a base line for a comparative study of the fine structure of various types of lymphocytes. Fixation with OsO4or glutaraldehyde, Epon embedding, and heavy metal staining were the principal techniques employed. Small thymocytes, with nuclei from 3.5 to 4.5 μ in diameter are in the vast majority. Our results, which in general confirm previous reports, show the thymocytes to be primitive, or undifferentiated in structure. Certain exceptions and additions were noted, however. There are no protoplasmic bridges between thymocytes and epithelial cells and no clear evidence of epithelial‐thymocyte transformations. The nucleus contains typical pores and in many cases a clearly defined finely granular nucleolus, although the latter is not evident in most of the smallest cells. Cytoplasmic fragments appear to be separating from thymocytes by a process similar to the separation of platelets from megakaryocytes. The existence of a special band of cytoplasm beneath the plasma membrane devoid of formed elements is described for the thymocytes. The possibility of the common occurrence of this zone in other cells, and its possible significance, are discuss

ISSN:0003-276X    

DOI:10.1002/ar.1091510104

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

年代:1965

数据来源: WILEY

摘要:

AbstractThe fine structure of intercellular substances and rounded cells of the incisor dental pulp of guinea pigs is described. The extracellular fibrils are of two kinds; collagen with typical cross‐striations, varying from 400–700 Å in diameter, and fine fibrils of 100–120 Å in diameter. In cross section the latter fibrils appeared to be composed of three or four smaller subunits of less than 50 Å in diameter. The collagen fibril in the dental pulp appear singly or in small bundles of about a dozen or more fibrils. The fine fibrils are often aggregated along the cell surface.The ground substances are finely granular to fibrillar and show localized clumping which is related to fibrillar elements. The ground substances form an incomplete covering of 200 Å or more in thickness surrounuding collagen fibrils. When the collagen fibrils make a bundle, the sheath of grouund substances around one fibril becomes fused with that of adjacent fibrils.Rounded cells including macrophages, lymphocytes and eosinophils are present in the pulp. The fine structure of these cells is similar to that found in the same types of cells previously observed in oth

ISSN:0003-276X    

DOI:10.1002/ar.1091510105

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

年代:1965

数据来源: WILEY

摘要:

AbstractVarious histochemical tests were performed to study the nonenzymatic components of lysosomes in the neurons of rat spinal cord. The lysosomal granules are periodic acid Schiff positive and this reaction can be blocked by acetylation, but not by bromination. They are performic and peracetic acid Schiff positive also. Both these reactions can be blocked by bromination. It is concluded that 1:2 glycol as well as ethylene groups are present. Lysosomes stain metachromatically after sulfation and are sudanophilic. They are chemical complexes containing protein, neutral polysaccharide, phospholipids and possibly glycolipids and are present in dendrites as well as axons. A topographical relationshiop exists between lysosomes and Golgi apparatus which was stained with nucleoside diphosphatase method. Lysosomes share Schmorl reaction with lipofuscin pigment. In some preparations there is a tendency for them to be localized along the cell membrane.

ISSN:0003-276X    

DOI:10.1002/ar.1091510106

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

年代:1965

数据来源: WILEY

摘要:

AbstractBlood flow patterns have been outlined in the chick embryo heart. The initial flow pattern adapts to the heart form but soon vascular forces affect cardiogenesis. Spiralling of the blood streams in the sinus venosus appears to lead to an expansion of this chamber. The atrial septum forms between parallel streams and evidence is presented that blood flow contributes to septation. Interatrial flow develops with a fusion of the inflow streams bringing the entire systemic venous return into the right atrium when the left atrium receives a small pulmonary return; the difference in pressures is believed to lead to perforation of the septal wall.The ventricular septum also forms between parallel bloodstreams. Inhibition of the left ventricular outflow, brought about by the application of trypan blue to the embryos, was associated with the production of ventricular septal defects. Higher pressures in the left ventricles, brought about by increased vascular resistance to these chambers, led to the defects as evidenced by left to right flow through the defects. An interpretation of the origin of this common congenital anomaly is thus offered.

ISSN:0003-276X    

DOI:10.1002/ar.1091510107

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

年代:1965

数据来源: WILEY

摘要:

AbstractThe morphology of the hypothalamo‐hypophyseal tract of 35 hibernating bats (Myotis lucifugus lucifugus) was studied in chrome‐alum‐hematoxylin‐phloxine‐stained serial coronal and sagittal sections. Vinyl acetate and wax‐plate reconstructions also aided in describing the two neurosecretory hypothalamic nuclei of this system. The most prominently defined nucleus, the supraoptic, consisted of a smaller portion rostral to the optic tract that was tenuously connected to a larger caudal portion. The probability that some of the posteriorly located cells of the caudal portion represent other hypothalamic nuclei is discussed. The shape and location of the paraventricular nucleus was more difficult to determine. Although the neurosecretory cells of this nucleus were similar in their irregular or eliptical shape to those of the supraoptic nucleus, the majority of the paraventricular cells were smaller and had less of an affinity for the chrome‐alum‐hematoxylin stain.The majority of CHP‐positive axons originating in the supraoptic nucleus converged toward the median eminence and terminated in the pars nervosa. Most of the axons from the paraventricular nucleus coursed laterally toward the supraoptic nucleus where they followed the pathway described from this nucleus. The localization of CHP‐positive material in the neurohypophysis is presented. Comparisons were made between the morphology of this system in the hibernating bat and that of other species of mammals reporte

ISSN:0003-276X    

DOI:10.1002/ar.1091510108

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

年代:1965

数据来源: WILEY

摘要:

AbstractIn an embryo of eleven and one‐half to twelve and one‐half days, the stomach, duodenum, liver and primordium of the dorsal pancreas were exciseden bloc, placed on a rayon grid supported by a grid of stainless steel and cultivated on a liquid medium of cock serum and extract of chick embryo for 8 or 10 or 12 days. The culture was incubated at 37°C in air supplemented by controlled oxygen and carbon dioxide.One‐hundred‐fifteen cultures were fixed in Bouin's solution and the sections stained with aldehyde fuchsin. Forty‐one cultures were fixed in Zenker's solution and the sections stained with hematoxylin and eosin. The 269 control pancreases were of two kinds: beginning controls taken at the time of the explantation (61 specimens); reference controls taken during the period from day eleven and one‐half postcoitum to day five postpartum (208 specimens).From an explant of a pancreatic primordium too primitive to have either islet or acinus, a culture could give rise to islets with granulated beta cells and acini with zymogen granules. The best‐developed islet in a ten‐day culture of an explant from a donor of eleven and one‐half days had an estimated granulation age of twenty‐one and one‐half days; thus the differentiationin vitrohad kept pace with that which occurredin vivoduring equal time in days. The best‐developed acinus in a 12‐day culture of a pancreatic primordium from an embryo of 12 and one‐half days had an estimated developmental age

ISSN:0003-276X    

DOI:10.1002/ar.1091510109

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.1091510101

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

年代:1965

数据来源: WILEY