scholarly journals Changes in the ovary of the mouse following exposure to X-Rays. Part IV.— The corpus luteum in the sterilized ovary, and some concluding experiments

1928 ◽  
Vol 102 (719) ◽  
pp. 385-396 ◽  
Keyword(s):  
Corpus Luteum ◽  
Degenerative Changes ◽  
Corpora Lutea ◽  
X Rays ◽  
X Ray ◽  
General Manner ◽  
Pregnancy And Lactation

The previous papers of. this series dealt only in a brief and general manner with the effect of X-ray sterilization on the corpora lutea. The present paper, the last of the series, includes more extensive work aimed at removing this deficiency. The work was begun by irradiating pregnant animals, but owing to the technical difficulties the greater part of it was carried out on lactating animals. In this paper it will be shown that the degenerative changes in the corpora lutea of pregnancy and lactation take place very slowly after sterilization, although they begin at the normal time. The corpora lutea become, in fact, practically permanent structures. The oestrous cycles of both these series of animals are dealt with elsewhere (9) by one of us, where it is shown that these “permanent” corpora lutea do not retain their oestrous-inhibiting power for any appreciable period after what would be the functional life of the normal corpus luteum. Moreover, the possible duration of lactation is not affected by sterilization at the beginning of suckling. The histology of the ovaries discussed in this paper is essentially similar to that found in the animals previously described (1,2, and 3) and need not be dealt with at length.

scholarly journals On the occurrence of the œstrous cycle after X-ray sterilisation. Part IV.–Irradiation of the adult during pregnancy and lactation; and general summary

1927 ◽  
Vol 102 (713) ◽  
pp. 51-62 ◽  
Keyword(s):  
Corpus Luteum ◽  
Young Female ◽  
Oestrous Cycle ◽  
Corpora Lutea ◽  
Extensive Investigation ◽  
X Ray ◽  
Long Period ◽  
Complete Destruction ◽  
Pregnancy And Lactation

In the first two parts of this series (2, 3) it was shown that the complete destruction of Graafian follicles as organised units by irradiation of the young female does not inhibit the appearance of the œstrous cycle when puberty is subsequently reached, while in Part III (4) the cycle in the non-mated adult was shown to persist unchanged after sterilisation. The clear deduction from these results is that neither follicles nor corpora lutea are essential to the main­ tenance of the œstrous cycle in the unmated animal. Extensive investigation was first made on the sterilisation of young animals, because preliminary experiments had shown that irradiation of the adult, during the functional life of the persistent corpus luteum at any rate, resulted in the permanent histological survival of corpora lutea vera, and it was desired in the first place to investigate the œstrous cycle after sterilisation in the absence of such a com­plication. This anticipation was not altogether realised, because in certain cases the young follicles, sent into atresia by irradiation, produced corpora lutea atretica. In the majority of cases, however, the ovaries from animals sterilised at birth or at weaning time were free from tissue of follicular derivation. Since it seemed possible that the removal of follicular competition might cause the persistent corpus luteum to function for an abnormally long period, experiments on this question have been carried out, and the present paper deals with the irradiation of the adult during the functional life of the persistent corpus luteum ( i. e ., irradiation during pregnancy and lactation), which results in the permanent histological survival of the orpora lutea vera, and with the effects of these structures on the recurrence of the œstrous cycle. The histology of the ovaries of the animals discussed in this paper is essentially similar to that found in the ovaries of non-parous adults after irradiation, and is con­sidered in collaboration with Dr. Brambell elsewhere.

scholarly journals Compensatory hypertrophy of the untreated ovary after unilateral X-ray sterilisation

1929 ◽  
Vol 105 (734) ◽  
pp. 36-42
Keyword(s):  
Corpus Luteum ◽  
Compensatory Hypertrophy ◽  
Point Of View ◽  
The Other ◽  
X Rays ◽  
X Ray ◽  
Pregnancy And Lactation ◽  
The Right

The technique of sterilising one ovary and allowing the other ovary to remain untreated was originally evolved (Parkes, 8) in order to make possible the accurate study of the rôle of the corpus luteum during pregnancy and lactation. Early in the experiments, however, it was noticed that litters from such unilaterally sterilised mice approximated closely to the normal size. It was later found that, with one ovary sterilised by X-rays, the other ovary undergoes true compensatory hypertrophy, such as has been observed by many authors to follow unilateral or sub-total ovariotomy (1, 4, 5, 6). Since the facts appeared to be of interest from the point of view of the mechanism of compensatory hypertrophy, the experiments on the corpus luteum were so arranged as to permit of collecting the data required to demonstrate hypertrophy of the reamining ovary. II.— Methods and Material . Sterilisation Technique .—The method of carrying out these unilateral irradiations has been described elsewhere (Parkes, 8) and it need only be said here that irradiation took place at 4 weeks old, and that in every case the right ovary was exposed, while the left was protected.

scholarly journals The corpora lutea of the mouse, with special reference to fat accumulation during the œstrous cycle

1930 ◽  
Vol 106 (747) ◽  
pp. 578-595 ◽  
Keyword(s):  
Special Reference ◽  
Corpus Luteum ◽  
Experimental Work ◽  
Laboratory Animals ◽  
Corpora Lutea ◽  
Mouse Ovary ◽  
Short Account ◽  
Cellular Degeneration ◽  
Pregnancy And Lactation ◽  
Considerable Period

Although the histological literature on the corpus luteum is very extensive, a description of cellular and fat changes in the organ, which distinguishes between the corpora lutea of ovulabion, pseudo-pregnancy, pregnancy, and lactation where these are differentiated, is still lacking for some laboratory animals. In view of experimental work now in progress, it was thought that a short account of the mouse corpus luteum on these lines might be of value. In the absence of pregnancy, old corpora lutea persist for a considerable period in the mouse ovary, and after the initial signs of cellular degeneration, which are not always very obvious, further changes are slow to occur. With suitable histological methods, however, it is possible to distinguish, even after they are fully developed, the corpora lutea belonging to the last one and sometimes two or more oestrous periods.

scholarly journals The suppression of oestrus in the rat during pregnancy and lactation

1938 ◽  
Vol 124 (837) ◽  
pp. 464-475 ◽  
Keyword(s):  
Corpus Luteum ◽  
Corpora Lutea ◽  
Luteal Tissue ◽  
Pregnancy And Lactation ◽  
Made In

It is well known that one function of the corpus luteum is the inhibition of oestrus. This fact has been established by experiments in which corpora lutea are removed and by experiments in which the functional life of corpora is prolonged. More recently it has been shown that the corpora exercise this inhibiting influence by means of their internal secretion. The exact part they play in the suppression of oestrus during pregnancy and in lactation in the rat is, however, still obscure. An attempt was therefore made in the following investigation to study the influence of destruction of luteal tissue on the return of oestrus and on the ripening of follicles, a technique which to our knowledge has not before been applied to the rat.

scholarly journals On the occurrence of the œstrous cycle after X-ray sterilisation. Part III.— The periodicity of œstrus after sterilisation of the adult

1927 ◽  
Vol 101 (711) ◽  
pp. 421-449 ◽  
Keyword(s):  
Female Mouse ◽  
Young Animal ◽  
Young Female ◽  
Oestrous Cycle ◽  
Germinal Epithelium ◽  
Corpora Lutea ◽  
X Rays ◽  
X Ray ◽  
Post Irradiation ◽  
Cyclic Phenomena

In Parts I and II (2, 3, 10, 11) of these series it has been shown that the destruction of the Graafian follicles in the young female mouse by exposure to X-rays does not inhibit the appearance of œstrous symptoms when the animals subsequently become mature. The conclusions arrived at were briefly as follows :— ( a ) After irradiation of the young animal the follicles disintegrate and are re-absorbed, this process being accompanied in its later stages by the proliferation of new tissue from the germinal epithelium. ( b ) When the animal becomes adult the ovary contains neither organised follicles nor corpora lutea vera, and consists largely of post-irradiation proliferation of the germinal epithelium. In spite of this, however, the cyclic phenomena of œstrus still appear.

Effects of bromocriptine-induced pregnancy on prolactin-secreting pituitary tumours

1981 ◽  
Vol 98 (3) ◽  
pp. 333-338 ◽  
Author(s):  
T. Bergh ◽  
S. J. Nillius ◽  
S.-G. Larsson ◽  
L. Wide
Keyword(s):  
Post Partum ◽  
Pituitary Tumour ◽  
X Rays ◽  
Pituitary Tumours ◽  
Pituitary Fossa ◽  
X Ray ◽  
Pregnancy And Lactation ◽  
Radiological Changes ◽  
The Mean

Abstract. Twenty-eight women with hyperprolactinaemia and amenorrhoea received bromocriptine treatment which resulted in 31 term pregnancies. Bromocriptine treatment was stopped as soon as pregnancy was established. Nineteen of the women had radiological signs of a pituitary tumour. The pregnancies were clinically un-eventful in all cases except one who developed headache. Post-partum sellar X-ray showed pregnancy-induced enlargement of the pituitary fossa in 4 of the 28 women. Regression of the radiological changes occurred in 3 of the 4 women within 2 years after the delivery. The women with abnormal sellar X-rays had no difference in the mean prolactin levels before treatment and after pregnancy and lactation while all the women with normal sellae had lower prolactin levels after pregnancy than before. Three women resumed regular spontaneous menstruations after pregnancy and lactation but only one conceived again. Thus, serious pituitary tumour complications are rare in hyperprolactinaemic women with bromocriptine-induced pregnancies. The pregnancy does not worsen the condition. Resolution of hyperprolactinaemia after bromocriptine-induced pregnancy is an unfrequent finding.

Delayed Post-Traumatic Midcarpal Dislocation

2007 ◽  
Vol 32 (5) ◽  
pp. 554-555 ◽  
Author(s):  
R. M. A. HAWKEN ◽  
S. M. FULLILOVE
Keyword(s):  
Degenerative Changes ◽  
Successful Outcome ◽  
X Rays ◽  
Wrist Injury ◽  
X Ray ◽  
Gradual Process ◽  
Post Traumatic ◽  
Wrist Fusion ◽  
Midcarpal Joint ◽  
Partial Wrist Fusion

We report a case of delayed post-traumatic volar midcarpal dislocation in a 39 year-old woman. The dislocation was a gradual process starting from the time of injury. Initial X-rays showed a normal midcarpal joint. By 6 weeks, lunocapitate subluxation was apparent radiologically and by the 18 week X-ray, midcarpal dislocation had occurred. This type of wrist injury has not been previously reported. Because of advanced degenerative changes in the lunocapitate joint, a partial wrist fusion was performed with a successful outcome.

scholarly journals On the occurrence of the œstrous cycle after X-ray sterilisation part II.—Irradiation at or before birth

1927 ◽  
Vol 101 (707) ◽  
pp. 71-95 ◽  
Keyword(s):  
Female Mouse ◽  
Young Female ◽  
Oestrous Cycle ◽  
Corpora Lutea ◽  
X Rays ◽  
Satisfactory Explanation ◽  
Cyclic Action ◽  
X Ray ◽  
Periodic Changes

The first paper of this series dealt with the effects on the œstrous cycle of X-ray sterilisation of the young female mouse at 3 weeks old. The conclusions arrived at were briefly as follows :— (1) Adequate exposure to X-rays causes disintegration of the Graafian follicles, and when puberty is subsequently reached the ovary contains no organised follicles, and in most cases no luteal or other tissue recognisable as being of follicular derivation. (2) In spite of this elimination of the cyclic structures of the ovary, the accessory organs of the majority of the animals experienced the normal periodic changes which constitute the œstrous cycle. (3) These results made it quite clear that neither Graafian follicles nor corpora lutea are necessarily essential for the periodic occurrence of œstrus, but no satisfactory explanation was arrived at of the means whereby the cyclic action of the œstrous-producing hormone is regulated. Since these results were entirely opposed to what has usually been thought of the regulation of the œstrous cycle, it seemed desirable that the same type of experiment should be repeated under somewhat different conditions.

scholarly journals The functions of the corpus luteum.—I. The mechanism of œstrus inhibition

1929 ◽  
Vol 104 (729) ◽  
pp. 171-182 ◽  
Keyword(s):  
Experimental Study ◽  
Corpus Luteum ◽  
Anterior Pituitary ◽  
The Other ◽  
Vaginal Smear ◽  
Corpora Lutea ◽  
X Ray ◽  
Inhibiting Action ◽  
Luteal Tissue ◽  
Test Objects

The methods by which the action of the corpus luteum can be studied have recently become greatly extended. It is possible to eliminate the corpora lutea by X-ray sterilisatioin, while, on the other hand, the production of luteal tissue may be intensely stimulated by the administration of anterior pituitary extracts. It is also possible to obtain extracts of corpora lutea which will substitute at least one function of the corpus luteum. As test objects, the vaginal smear test for œstrus inhibition, the placentoma test for the sensitization of the uterus, and the experimental study of the rabbit mammary gland, provide easy means of ascertaining luteal activity. It is intended, in the series of reports of which the present is the first, to record an investigation into the physiology of the corpus luteum carried out by means of these various techniques. In previous paper (Parkes and Bellery, 10, 11) the evidence that the corpus luteum has an œstrus-inhibiting action was fully discussed, and a method of preparing an œstrus-inhibiting extract of the organ was described. In the present paper various lines of work bearing on this problem will be recorded It has been pointed out before (Parkes, 8) that, since obliteration of the corpora lutea in the ordinary unmated cycle of the mouse does not affect the length, the corpora lutea under these conditions can have neither an œstrus-promoting nor an œstrus-inhibiting action. After sterile copulation, however, the corpora lutes of ovulation persist and interval before the next œstrus period is prolonged from 4 days to about 12 days. In this paper it is hoped to be able to demonstrate the dependence of the latter upon the former event.

White-Light Coronal Structures: Streamers and CMEs

1994 ◽  
Vol 144 ◽  
pp. 82
Author(s):  
E. Hildner
Keyword(s):  
Emission Line ◽  
Electron Density ◽  
White Light ◽  
Coronal Mass Ejections ◽  
X Rays ◽  
Solar Cycles ◽  
Temperature Function ◽  
X Ray ◽  
Eclipse Observations ◽  
Coronal Structures

AbstractOver the last twenty years, orbiting coronagraphs have vastly increased the amount of observational material for the whitelight corona. Spanning almost two solar cycles, and augmented by ground-based K-coronameter, emission-line, and eclipse observations, these data allow us to assess,inter alia: the typical and atypical behavior of the corona; how the corona evolves on time scales from minutes to a decade; and (in some respects) the relation between photospheric, coronal, and interplanetary features. This talk will review recent results on these three topics. A remark or two will attempt to relate the whitelight corona between 1.5 and 6 R⊙to the corona seen at lower altitudes in soft X-rays (e.g., with Yohkoh). The whitelight emission depends only on integrated electron density independent of temperature, whereas the soft X-ray emission depends upon the integral of electron density squared times a temperature function. The properties of coronal mass ejections (CMEs) will be reviewed briefly and their relationships to other solar and interplanetary phenomena will be noted.

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