摘要:

AbstractHistosol is a non‐flammable solvent mixture of synthetic aromatic hydrocarbons with a flash point of 124°F (T.C.C.). It has a lower vapor pressure and evaporation rate than other organic solvents, such as xylene, routinely used as clearing and deparaffinizing agents. Although both xylene and Histosol clear and deparaffinize soft organ tissues effectively in the preparation of permanently mounted stained slides, Histosol appears, in many instances, to be the choice solvent: tissues are easier to section; cell bordrs and cell surface modifications are most distinct; cytoplasmic eosinophilia is more vivid; and nuclear detail is improved. Of prime importance, Histosol is a safer and more efficient solvent for use in histological and pathological laboratori

ISSN:0003-276X    

DOI:10.1002/ar.1091970302

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

年代:1980

数据来源: WILEY

摘要:

AbstractThe ultrastructural and oxidative metabolic effects of D‐penicillamine were examined in hepatocytes of mice fed various concentrations of the drug for periods up to 11 days. In virtually all animals studied, membranous material in the form of whorls, sheaves, and irregular networks was observed in some bile canaliculi. In several mice a few mitochondria were substantially enlarged, with diameters of 4‐6 μm. In other animals some mitochondria became quite elongated, measuring 10 μm in length but only 0.5 μm in width. Certain mitochondria had small deposits of dense material in their outer compartment. Lysosomes contained numerous small dense particles; aggregates of these particles were also observed free in the cytosol. Despite these alterations, the vast majority of hepatocytes showed no changes whatsoever. Study of isolated hepatic mitochondria derived from the experimental animals showed no alterations in oxidative metabolism. It may be concluded that, unlike other copper‐chelating agents, D‐penicillamine has little significant morphological and biochemical effect on mouse hepatocytes, even when its concentration exceeds standard clinic

ISSN:0003-276X    

DOI:10.1002/ar.1091970303

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

年代:1980

数据来源: WILEY

摘要:

AbstractThe present study suggests a mixture of buffered osmic acid and 1.5% potassium ferricyanide as a post‐fixation to improve the fixation of neural tissue. This procedure results in an improved preservation of membranes as well as cytoplasm and cytoplasmic organelles. It is to be emphasized that the quality of the initial perfusion is the primary determinant of quality of the fixation, but the addition of 1.5% potassium ferricyanide to post‐fixation fluid makes good fixation better and allows data to be gathered from otherwise unusable mater

ISSN:0003-276X    

DOI:10.1002/ar.1091970304

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

年代:1980

数据来源: WILEY

摘要:

AbstractOsteogenesis was inhibited when mandibular processes from 3 1/2‐day‐old embryos were cultured in BUdR, LACA, α, αβ‐Dipyridyl, 4‐Methylumbelliferone, and 4‐Methylumbelliferyl‐β‐D‐glucoside or β‐D‐xyloside. Mandibular processes were then cultured in the test substances for 3 days, enzymatically separated into their epithelial and ectomesenchymal components, combined with mandibular components from untreated embryos, and either organ‐cultured or grafted to chorioallantoic membranes of host embryos. Osteogenesis was inhibited when treated epithelium, but not when treated ectomesenchyme, was present in the tissue recombinations.Analysis of the known action of these inhibitors indicates that proliferation, hydroxylation of collagen, and synthesis of proteoglycans by epithelial cells are all necessary components of this osteogenic epithelial

ISSN:0003-276X    

DOI:10.1002/ar.1091970305

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

年代:1980

数据来源: WILEY

摘要:

AbstractThe development of mouse embryos in culture from the implantation to the head‐fold stage was sequentially examined. Our goal was to compare the morphology of embryos grown in vitro to those developed in vivo, published in standard texts, and to delineate the stages involved in the process of tissue differentiation and organization. Mouse blastocysts (stage 6) were collected at 3.5 days p.c. and cultured. Attachment of the blastocysts occurred on the second day of culture (stage 8). Following the collapse of the blastocyst endoderm cells began to migrate and to encircle the inner cell mass. At 2 days in culture the embryonic and extra‐embryonic ectoderm became distinguishable and the proamniotic cavity appeared (stage 9). Egg cylinders began to project above the substrate at 2.5 days in culture (stage 10) and to progress through the stages observed in vivo. At 4 days a posterior amniotic fold began to form (stage 11) and was followed at 5 days by the formation of the chorion, the appearance of mesoderm, exocoelom, and head fold (stage 12). At 6 days in culture the embryo had differentiated longitudinally and developed an allantois, blood islands, Reichert's membrane, head process, and primitive streak. At 7 days somites as well as the neural fold and heart were observed (stage 14) and were followed by further differentiation at 8 days (stage 15). These observations indicate that apparently normal embryo development can be maintained in vitro through the early stages of organogenesis, thus providing a unique opportunity for investigating the regulation of early mammalian developm

ISSN:0003-276X    

DOI:10.1002/ar.1091970306

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

年代:1980

数据来源: WILEY

摘要:

AbstractPressure‐volume characteristics of whole lungs were measured in euthyroid rats and in rats fed 0.4% desiccated thyroid for eight weeks. The lungs were degassed by incising the diaphragm after the animals had breathed 100% oxygen for ten minutes. The pressure‐volume characteristics were measured by inflating and deflating the lungs at a rate of 3.5 cc/min. Total lung capacity (TLC) was considered to be that volume of air required to produce a transpulmonary pressure of 30 cm H2O. At TLC there was 35% greater lung volume in the thyroid‐treated animals than in their littermate controls. Similar results were observed in saline‐filled lungs. Alveolar surface area (Sa) increased from 0.28m2in the lungs of control animals to 0.75m2in lungs of thyroid‐treated animals. There was an 85% increase in the alveolar surface density (Sva) in the thyroid‐treated animals. These results, obtained by morphometric analysis, suggest that greater lung volume in the thyroid‐treated animals resulted from alveolar hyperplasia or

ISSN:0003-276X    

DOI:10.1002/ar.1091970307

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

年代:1980

数据来源: WILEY

摘要:

AbstractA condition of protein‐calorie malnutrition was precipitated in young Sprague‐Dawley male rats at 20 days of age using an 8% low protein diet (LPD). At five‐day intervals for up to 50 days of age, the rats were studied to determine the effect of an LPD on the reproductive axis of the endocrine system. Daily monitoring of the body weight, as well as the consumption of food, kilocalories, and protein was conducted. The same parameters were followed over the identical time peroid in a group of animals designated as controls which were fed a standard laboratory diet (SLD) containing 27% protein. The controls showed a linear growth rate over the 30‐day experimental period. In comparison, the malnourished rats grew more slowly so that by 50 days of age, their mean body weight was 68.9 ± 3.1 g as compared to 249.1 ± 6.1 g for the controls. The daily food, kilocalorie, and protein intake by the experimental animals were also appreciably less. The pituitary gland, ventral prostate gland, testes and liver were smaller in the animals fed the LPD. This was observed as early as five days after initiating the dietary regimes and remained a consistent observation until the end of the experiment. In general, the absolute weights of these organs in the 50 day‐old malnourished rats were similar to those found in 25 to 26 day‐old animals fed the SLD. The relative weights of the pituitary gland and liver remained similar between the two animal groups. The testes and ventral prostate gland, however, were relatively smaller in the malnourished animals at nearly every time interval studied. On light microscopic examination of the testes, it was found that normal maturation of the germ cells failed to occur in all but one of the experimental animals, whereas maturation proceeded normally in the rats fed the SLD. Serum luteinizing hormone (LH), follicle stimulating hormone (FSH), prolactin (PRL), and testosterone were lower in the malnourished animals at all ages studied. These hormones did not exhibit the fluctuations that were seen in the controls and are typical in rats that are becoming sexually mature. The effect of protein deficiency on the concentration of the pituitary gonadotrophins was more varied. FSH concentrations were consistently lower, PRL was moderately affected, and LH remained essentially unchanged. Hypothalamic LH‐releasing hormone was measured and found to be significantly less in the rats fed the LPD at most of the time intervals examined. These results indicate that the hypothalamo‐hypophyseal‐gonadal axis is impaired when the consumption of proteins and calories is decreased. The possible involvement of extrahypothalamic centers in the control of hormone secretion in the protein‐defic

ISSN:0003-276X    

DOI:10.1002/ar.1091970308

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

年代:1980

数据来源: WILEY

摘要:

AbstractThe incidence and structure of equine and murine chondrocytic cilia were studied using serial sections and transmission electron microscopy. Overall, 96% of all equine chondrocytes and 100% of all murine chondrocytes had one cilium. The structure of these cilia included rootlets, basal feet, alar sheets, and an axoneme of nine peripheral doublets which progressively bent and terminated as they coursed towards the tip of the ciliary shaft. Together with the previous studies on neonatal and adult canine chondrocytic cilia, we conclude that the structure and incidence of chondrocytic cilia does not vary among species, regions within a joint, cell types, or age groups.

ISSN:0003-276X    

DOI:10.1002/ar.1091970309

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

年代:1980

数据来源: WILEY

摘要:

AbstractThe changes in the fractional volume of six structural components in the spleens of Balb/C mice injected with Herpes simplex virus Type 2‐transformed cells (H238 tumor cells) were quantitated during progressive tumor growth. Spleen sterology was performed at three time intervals during the early stages of tumor development. The results revealed that the volume of the compact myeloid tissue and reaction centers of lymphoid nodules increased about four‐ to five‐fold from 10 to 33 days after H238 tumor cell injection. A progressive increase was also seen in the red pulp volume. Although an increase in volume of the marginal zones around the lymphoid nodules was evident early during the test period, by day 33 the mean value was similar to the control value. These results indicate that the spleen undergoes significant morphological changes in three splenic components during progressive growth of a tumor produced by subcutaneous injection of a virally‐transformed ce

ISSN:0003-276X    

DOI:10.1002/ar.1091970310

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

年代:1980

数据来源: WILEY

摘要:

AbstractEarly corpora lutea (CL) of the rat were histologically examined on Day 1, 2, 4, and 6 of gestation. Measurements were taken of total volume and of the number of luteal and endothelial cells in one CL of both ovaries of five rats at each stage examined. CL volume increased over the 6 days from ‐‐0.76 to 1.39μl and peripheral plasma progesterone levels from 8.1 to 33.2 ng/ml. The number of luteal cells per CL (range 303,000 to 37,000) did not significantly change, and there was no evidence of mitosis or death amongst these cells. Luteal cell volume increased from 1.74 to 3.49 pl and nuclear volume from 0.25 to 0.38 pl, the former being the major cause of CL growth. The CL appeared to be richly vascularized, even on Day 1, and the number of endothelial cells per CL (range 289,000 to 354,000) remained relatively constant over the period examined.It was concluded that the number of luteal cells per CL is determined prior to or around ovulation in the rat and that subsequent growth of the CL is due to hypertrophy and not hyperpl

ISSN:0003-276X    

DOI:10.1002/ar.1091970311

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

年代:1980

数据来源: WILEY