摘要:

One‐year‐old selectively parathyroidectomized rats were found to have lost the ability to adapt themselves to a reduced calcium intake. Of importance in this respect was certainly the demonstrated inability to mobilize skeletal calcium to the blood. Thus, when the normal intake of calcium in the diet is reduced in the adult intact rat, skeletal calcium reserves must become mobilized with resulting osteoporosis. Histological and morphometric analyses of the adrenal glands showed no apparent effect of the parathyroidectomy upon the functional state of the adrenal cor

ISSN:0365-4184    

DOI:10.1111/j.1699-0463.1975.tb01352.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

The effects of selective parathyroidectomy on the adaptation to a low calcium intake were studied in one‐year‐old male rats. Parathyroidectomized animals showed increased net absorption of intestinal calcium compared to that of intact animals both at a normal and at a low intake of dietary calcium. The difference was highly significant on the low level of dietary calcium. In the parathyroidectomized animals, significantly higher values were found in the group of rats fed the low calcium diet than in those supplied the calcium supplemented diet. Urinary calcium excretion was reduced because of the reduced plasma calcium level. While there was no disturbance of intestinal calcium absorption, selective parathyroidectomy resulted in a reduced ability to mobilize skeletal calcium as shown in a previous study. This was found to be necessary for the adaptation to a low calcium intake in the adult ani

ISSN:0365-4184    

DOI:10.1111/j.1699-0463.1975.tb01353.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

The effect of testosterone, progesterone, and 17‐β‐oestradiol on the incorporation of tritiated thymidine into DNA was studiedin vitrousing cell suspensions from DMBA‐induced rat mammary carcinomas and subcutaneous sarcomas. Both stimulatory and inhibitory effects of the hormones were seen. The two types of tumour reacted similarly. The validity of hormonal responsivenessin vitrocompared within vivois dis

ISSN:0365-4184    

DOI:10.1111/j.1699-0463.1975.tb01354.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

Specimens of DMBA‐induced mammary tumour, DMBA‐induced subcutaneous sarcomas, and virus induced sarcomas in the rat were incubated for 24–72 hours as organ cultures. The effect of various concentrations of testosterone, progesterone, and 17‐β‐oestradiol on cell survival and multiplication was measured as changes in incorporation of H3‐TdR into DNA. All three types of tumour reacted to the hormones. Statistical analysis of data demonstrated possible influence of factors other than hormone treatment. The specificity of hormone sensitivity assaysin vitroi

ISSN:0365-4184    

DOI:10.1111/j.1699-0463.1975.tb01355.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

M. lepraemuriumwas injected subcutaneously into two inbred strains of mice, C3H and C57/BL, in order to study the local reaction at various time intervals. Within 6 hours an acute inflammatory reaction developed at the site of injection. In the course of the following days it was replaced by a mononuclear infiltrate. The influx of mononuclear cells appeared to be somewhat greater in C57/BL than in C3H mice. Apart from this, little difference was observed between the two strains until at 4 weeks when a vigorous granulomatous reaction developed in the C57/BL strain. This reaction apparently arrested further local spread of the infection. The histological appearance of the infiltrate indicated that a delayed hypersensitivity reaction was taking place. No signs of such reaction was observed in the C3H strain.

ISSN:0365-4184    

DOI:10.1111/j.1699-0463.1975.tb01356.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

Mice of the inbred strains C57/BL and C3H were inoculated subcutaneously on the thorax withM. lepraemurium.In C57/BL mice a firm, raised, sharply defined nodular infiltrate developed 4 weeks afterwards, while in the C3H strain the infection produced a soft, flattened infiltrate with ill‐defined margins, which did not become palpable until 10 weeks after inoculation. A limited spread of the infection occurred early in both strains, but apparently multiplication of the microorganisms was very restricted in C57/BL mice; progressive, disseminated growth of the bacilli was observed in the C3H strain only. In C57/BL mice the granulomatous reaction, developing 4 weeks after inoculation and leading to abcess formation, ulceration and scar formation, apparently inhibited both local multiplication and further spread of the bacilli. In C3H mice no host reaction was detected and the bacilli appeared to grow unrestrictedly. In some C57/BL animals, decrease in host resistance occurred during the infection, causing reactivation of the local lesion and an apparently rapid proliferation of bacilli. Observations regarding the lesions in superinfected animals indicated that a systemic immune reaction develops in the C57/BL strain about 4 weeks after inoculation, whereas this does not occur in the C3H strai

ISSN:0365-4184    

DOI:10.1111/j.1699-0463.1975.tb01357.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

Eight peripheral and 2 central oral giant cell granulomas have been studied in the electron microscope in order to examine the structure and nature of the vessels. The vascular wall was composed of a continuous layer of endothelial cells resting on a basal lamina, which was frequently multilayered. The lamina also surrounded scattered subjacent pericytes. The endothelial cells overlapped slightly so as to form narrow intercellular spaces. Based on these observations the vessels are supposed to be postcapillary venules. Dark cells exhibiting degenerative features were encountered in the endothelial lining of most vessels. Small gaps and larger defects in the vascular lining allowed direct continuity between the lumen and the perivascular tissue. It is suggested that the extreme extravasation of red blood cells frequently observed in oral giant cell granulomas may be mediated through this incomplete lining.

ISSN:0365-4184    

DOI:10.1111/j.1699-0463.1975.tb01358.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

A new method for embedding of small animals and animal organs in plastic is described. After the material has been fixed in solutions preserving its colour, and dehydrated gradually using an aqueous solution of glycerol and potassium acetate it is embedded in methylmetacrylate. The method is described in detail and involves moulding at ‐5

ISSN:0365-4184    

DOI:10.1111/j.1699-0463.1975.tb01359.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

The mechanism of neosynthesis of the human tumor‐associated fetal antigen alpha‐fetoprotein (AFP) in a variable percentage of patients with testicular, ovarian and extragonadal germ cell tumors has generally been considered unknown or beyond any simple explanation. Of decisive importance is the cellular basis for AFP production 1. in ontogenesis and 2. in malignancy as dependent on an exact tumor histogenesis. Based on (1) the histogenetic‐embryologic classification of germ cell tumors and the concept of yolk sac tumor (or endodermal sinus tumor), (2) the available clinical and experimental observations, and (3) the immunofluorescent localization of AFP in the endodermal sinus tumor of the human testis, it is concluded that AFP synthesis in these neoplasms is explained by the fact that they contain yolk sac endoderm, which produce AFP analogous with the physiological AFP synthesis by the fetal yolk sac in early embryoge

ISSN:0365-4184    

DOI:10.1111/j.1699-0463.1975.tb01360.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY

摘要:

In a series of 235 autopsies, changes in the subcapsular thoracic fascia similar to elastofibroma dorsi (Järvi&Saxén1959,‐et al.1969) were found in 39 cases, all at least 58 years old. In people over 55 years, the frequency was 24.4 per cent in females and 11.2 per cent in males. In addition to hypertrophy and secondary degeneration of elastic fibres, necrosis of collagenous‐, adipose‐, muscular‐, and nervous tissue, as well as formation of clefts, cysts and bursae was found in 85 per cent of cases presenting elastic changes—both in connection with them and outside the degenerated areas—as well as in 39 per cent of cases where no elastic degeneration occurred. Other changes included extensive scarring of the tissue, followed by reduction of fat and, more seldom, oedema and inflammatory infiltration. Breaks in the elastic cage, necrosis and fibrosis of arterial walls were found in 44 per cent of cases of elastic degeneration and in 14 per cent of cases without degeneration. In veins, more extensive wall fibrosis occurred, leading to necrosis; in cases of elastic degeneration the adventitial elastic network was also involved. Venous changes were found in 90 per cent of the cases of elastic degeneration and in 30 per cent of cases without degeneration. Direct mechanical stress on elastic tissue may be an important cause of hypertrophy and secondary degeneration of elastic fibres, and also of diffuse increase of collagenous tissue. On the other hand, nutritional deficiency due to failing resistance of the vascular system against friction of the scapula and streching movements of the upper extremities may play a main part in necrotic t

ISSN:0365-4184    

DOI:10.1111/j.1699-0463.1975.tb01361.x

出版商:Blackwell Publishing Ltd    

年代:1975

数据来源: WILEY