ISSN:0003-276X    

DOI:10.1002/ar.1091490402

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

年代:1964

数据来源: WILEY

摘要:

AbstractProcedures for experiments on the embryo of the turtle are described. Methods of obtaining the gravid females, their handling, and preoperative preparation of the egg are described. The actual operation can be carried out much as it is done on the chick embryo. Post‐operative care is described. Survival can be satisfactory. Hazards of the procedure are discussed and means of controlling them indicated. Most of the experiments were done with embryos of the common snapping turtle,Chelydra serpentina.A few experiments were done with embryos of the painted turtle,Chrysemys picta, and of the soft‐shelled turtle,Trionyx spiniferus.The embryos of the painted turtle promise to be well suited to use for experimental studies. The soft‐shelled turtle is not such a promising

ISSN:0003-276X    

DOI:10.1002/ar.1091490403

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

年代:1964

数据来源: WILEY

摘要:

AbstractWith the aid of a Zeiss operation microscope, a dissection was made of the nerves to the blood vessels of the dorsum and sides in the two feet of the cadaver of an adult man. No obvious vascular nerve issued from the saphenous nerve. The terminations of the dorsal metatarsal and interdigital arteries and veins over the two medial thirds of the dorsum of the foot were supplied by extremely thin nervelets which originated chiefly from the medial branch of the superficial peroneal nerve. The sural nerve issued conspicuous filaments to the lateral interdigital and metatarsal blood vessels, to the lateral calcaneal arteries and to the talo‐calcaneal region. These findings provided a firmer anatomical basis for the interruption of the vascular nerves of the dorsum and sides of the foot by blocking with analgesic agents or by crushing the superficial peroneal, sural and saphenous nerves above the ankl

ISSN:0003-276X    

DOI:10.1002/ar.1091490404

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

年代:1964

数据来源: WILEY

摘要:

AbstractLarge intracellular ice formations are assumed to be more damaging than small ones. Nuclear alteration, such as pycnosis, generally is considered a reflection of reduced vital cellular functions. Evidence is presented which shows, on the basis of rate of oxygen consumption, that survival of kidney cells is greater after the formation of large rather than small intracellular ice artifacts, and that nucelar alteration such as pycnosis does not indicate the degree of damage to a vital function, their respiratory activity. Findings agree with those based upon autotransplantation of skin (Anat. Rec.,144: 171–191, '62). It is suggested that mitochondria are one of the cellular sites of freeze‐thaw injury and that the mechanism of freezing injury may differ in nucleus and ctyoplasm.Microscopic appearance of ice artifacts formed in cells of mouse kidney slices after slow (1.5° and 3.0°C/min) and rapid (19° and 38°C/sec) freezing to −75° and −196°C was preserved by the author's freeze‐drying method. Control (unfrozen) and frozen‐thawed slices were fixed in Bouin's fluid and processed routinely for study of microstructure. Oxygen consumption of parallel groups of control and frozen‐thawed slices was measured by the conventional Warburg manometric technique. The data revealed that: (1) the size of intracellular ice artifacts was 5 to 17 times larger in slices frozen at slow than at rapid rate; (2) Q02of cells in slowly frozen tissue slices (average of 21% of control Q02) was significantly greater than rapidly frozen cells (average of 9% of control Q02); (3) Nuclear pycnosis, crenation and vacuolation were more extensive in cells which

ISSN:0003-276X    

DOI:10.1002/ar.1091490405

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

年代:1964

数据来源: WILEY

摘要:

AbstractThe anatomical and histological picture following intravenous injections of several concentrations of aqueous solutions of Alcian Blue has been described. Alcian Blue granules can be found in all cases within the reticulo‐endothelial cells of the body in lungs, spleen, liver and bone marrow and in the kidney.The greatest concentration of the dye is found within the renal glomeruli. It is in such concentration as to enable one to see individual glomeruli with the 10 × magnification of the dissecting microscope. On high power (950 ×) the dye can be seen as granules within the endothelial cells and podocytes of the glomerulus, as well as in the cells of the glomerular stalk. No Alcian Blue has been identified within the macula densa.Certain difficulties due to the solubility of the dye in sections are mentioned. Present means of meeting them are covered. Also discussed are follow‐up studies being undertaken and possible implications of the proc

ISSN:0003-276X    

DOI:10.1002/ar.1091490406

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

年代:1964

数据来源: WILEY

摘要:

AbstractA new and relatively simple technique for conducting developmental neurology experiments is described. This technique consists of subjecting rats less than four days in age to a collimated source of external beta radiation that can be directed to selected parts of the brain. Use of this method yields the following advantages: (1) the size relationships of the parts of the brain can be altered, (2) bilateral asymmetry of the cerebrum, and/or cerebellum can be produced, (3) chronic functional defects which develop as the rat develops can be obtained, (4) the experimenter may selectively destroy any site in the brain provided that it is superficial enough, and (5) foci of epilation appear on the scalp and serve as markers. The limitations of this method are also discussed.

ISSN:0003-276X    

DOI:10.1002/ar.1091490407

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

年代:1964

数据来源: WILEY

摘要:

AbstractHuman embryonic myocardial tissues ranging from eight to eighteen weeks of development were prefixed and dissected in buffered formaldehyde, postfixed in buffered OsO4and processes for Epon embedding. At these stages of development the myocardial cells contain an abundance of sarcoplasm with a sparse random distribution of myofibrils that frequently appear branched. The A, I and Z bands exhibited in the adult myocardial cells are also observed in these stages of development. However, the M line is only slightly apparent, while no H band was observed. The mitochondria are not arranged in parallel arrays as found in the adult, but appear to be randomly distributed throughout the interfibrillar sarcoplasm. An array of tubules, cisternae and vesicles that comprise the sarcoplasmic reticulum is also distributed throughout the interfibrillar sarcoplasm. In some areas this tubular system appears as vesicles with small dense granules along its outer surface, while in other areas it appears smooth. The distribution and orientation of the sarcoplasmic reticulum is far less pronounced in the embryonic stages examined in this study than that reported for the adult myocardium. Dense granules (150 to 350 Å) appear as clusters or aggregates of granules in the sarcoplasm and are similar to the glycogen granules described by other investigators. The intercalated disc is observed at the junction of two opposing cells and occurs with less frequency than the intercalated disc in the adult myocardium

ISSN:0003-276X    

DOI:10.1002/ar.1091490408

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

年代:1964

数据来源: WILEY

摘要:

AbstractHost tissue underlying skin homografts and isografts was removed 4 to 8 days after grafting and fixed in osmium tetroxide for electron microscopy. The skin homograft bed was composed of a dense mass of cells, with bundles of collagenous fibers interspersed. Two types of large, elongated cells with elongated nuclei were commonly seen, one characterized by extensive granular endoplasmic reticulum and the other by masses of free ribosomes. The former corresponds to descriptions of fibroblasts and the latter resembles a lymphoid cell but is considerably larger than those seen in peripheral blood. These two cell types contain most of the ribosomes present in the graft bed. Numerous macrophages and neutrophils were present also. The skin isograft bed was similar except that no large elongated cells with masses of free ribosomes were found. The cell types identified with the electron microscope correspond to the cell types proposed earlier on the basis of light microscope radioautography with thymidine‐H3. It is suggested that the elongated, hypertrophied, lymphoid cell, rather than the macrophage, is responsible for homograft rejectio

ISSN:0003-276X    

DOI:10.1002/ar.1091490409

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

年代:1964

数据来源: WILEY

摘要:

AbstractHistological techniques were used to obtain fiber counts, capillary counts, fiber diameters, and capillary‐fiber ratios in the adult rat heart. Based on measurements of 3,600 fibers in six rats, the means and standard deviations of the fiber diameters for the left and right ventricles were 11.8 ± 4.8 and 11.5 ± 4.3 μ respectively. The corresponding capillary‐fiber ratios were 0.92 ± 0.23 and 0.90 ± 0.33. The differences between the right and left ventricles were not statistically significant. Statistical analysis was used to evaluate the reproducibility of the results. The frequency distribution of the fiber diameters was found to be unimodal in both right and left ventricles suggesting that only one group of fiber sizes is involved. It was found that fiber counts could be used as an indication of fiber size under ordinary conditions provided that the total number of fibers counted is

ISSN:0003-276X    

DOI:10.1002/ar.1091490410

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

年代:1964

数据来源: WILEY

摘要:

AbstractFour stocks (C, C‐57 Bl, DBA and Swiss albino) of mice were fed a high‐fat (28%), low‐protein (8%), hypolipotropic diet for 3–480 days. Lipotropic activities of supplements of betaine and carnitine were evaluated. There were no strain‐limited hepatic responses to the diet or to the action of the lipotropes. Without lipotropic supplements, parenchymal liposis (sudanophilia of frozen sections) was progressively incremental in all lobular zones for approximately 90 days. Subsquently, lobular liposis decreased and the remaining fat was concentrated in the middle zone within cords of fat‐laden cells radiating in a stellate pattern. With choline supplemention, liposis was limited to small amounts of fat within cells that composed the stellate pattern. Betaine displayed a level of lipotropic activity approximating one‐half to three‐fourths that of choline. The lipotropic activity of carnitine was marginal and inconsistent. The combination of betaine and carnitine demonstrated some synergistic action. No parenchymal hyperplasia was observed. The intralobular reticulum increased in some livers, primarily around the central and intercalated veins, but no lobular dist

ISSN:0003-276X    

DOI:10.1002/ar.1091490411

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

年代:1964

数据来源: WILEY