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71.
In Britain, teenage pregnancy is seen as both a cause and a consequence of social exclusion. The emphasis on 'prevention' of teenage pregnancy and a limited conception of 'support' within the Teenage Pregnancy Strategy (Social Exclusion Unit, 1999) positions parenthood for young people as a negative choice; this dominant discourse is likely to influence young people's reproductive decisions and experiences. With this in mind, this article focuses on a key finding from a multidisciplinary empirical research study, conducted in a city in the West Midlands of England, which considered and explored young people's experience of support before and following termination and miscarriage. Data were collected via in-depth interviews with professionals and practitioners (n = 15), young mothers (n = 4) and one young father. Although termination and miscarriage are generally perceived as distinct and different issues, the data suggest that the issues become more blurred where younger women are concerned. The experiences of young, 'inappropriately pregnant teenagers' often remain unacknowledged and devalued. This analysis highlights the social and political context in which young women experience termination and miscarriage, and suggests that termination and miscarriage should be acknowledged as significant medical, social and emotional events in the lives of young people.  相似文献   
72.
Primary hypertrophic osteoarthropathy is a condition characterized by clubbing, arthropathy and periostosis of long tubular bones. Three variants of primary hypertrophic osteoarthropathy are distinguished: pachydermoperiostosis, which shows as additional symptom pachydermia; cranio-osteoarthropathy, which has a decreased neurocranium ossification as additional feature; and a secondary form. Primary hypertrophic osteoarthropathy is also genetically heterogeneous, with evidence for both autosomal dominant and autosomal recessive inheritance. We describe two sibs with cranio-osteoarthropathy and briefly review previously reported cases. The present cases demonstrate the phenotypic variability of the condition. The consanguinity in the present family and analysis of previously described cases support autosomal recessive inheritance for cranio-osteoarthropathy.  相似文献   
73.
A total of 134 controlled natural IVF (nIVF) cycles were reviewed retrospectively and compared with 370 stimulated IVF (sIVF) cycles. The clinical pregnancy rate per embryo transfer following nIVF was 27% and 47% in sIVF cycles for patients aged less than 35. However, natural cycle patients could attempt consecutive cycles with much less impact on their lives, both medically and financially. In patients under 35 years of age, the choice of controlled nIVF reduces the cost and risk to the patient, permitting her to have multiple, consecutive attempts, and cumulatively offers a clinical pregnancy rate which approaches that of sIVF. The multiple pregnancy rate in nIVF is significantly reduced compared with sIVF treatment cycles. In patients over 35 years of age the benefits of nIVF were much less evident (clinical pregnancy rate: 8% per embryo transfer) and the opportunity to transfer multiple embryos in these patients seems to be advantageous.  相似文献   
74.
75.
Two oriental strains of T. pallidum of Chinese origin were compared with two well known occidental strains, the Nichols and the Zinsser-Hopkins, on the basis of the clinical reaction to infection in the rabbit. Four experiments were carried out, two each in Peiping and New York. Animals from American and Chinese sources were represented in each experiment. The results obtained showed that the reaction to both Chinese strains was generally comparable to that of the American strains. But with both Chinese strains, lesions of the eyes were more frequent, the time relations of certain phases of the reaction were shortened, and there was a higher incidence of complete recovery (latency) within the observation period. In view of the well known variability of the syphilitic reaction, however, it was not felt that these qualitative differences in clinical response could be ascribed to inherent or biologically fixed properties of the strains.  相似文献   
76.
A study of the red blood cells, hemoglobin, blood platelets, and the total and individual white blood cells was made on 180 male rabbits of known age and representing fifteen standard breeds. An attempt was made to eliminate or bold constant such variables as age, sex, season, time of examination, technical errors, food, housing, and disease. The mean, variance of the mean, and standard deviation were calculated for each breed sample and for the group as a whole. An analysis of the variance showed that the variation between the breed samples was significantly greater than the variation within the breed samples for the red blood cells, hemoglobin, blood platelets, total white blood cells, basophiles, eosinophiles, and lymphocytes per cubic millimeter and in per cent and the neutrophiles in per cent. No significant variations were detected in the monocytes except when the breeds were divided into heavy and light breeds. No variation in the neutrophiles per cubic millimeter was detected; a large number of the breeds had exactly the same mean neutrophile level. Characteristic blood formulae were found for the various breed samples having an adequate numerical representation. It was concluded that the varying blood formulae could not be explained on any other, except an hereditary (genetic) basis.  相似文献   
77.
By means of injections made into the coronary arteries of beating hearts it has been possible to determine the number of capillaries in the normal heart muscle. This study has shown a very rich blood supply with an average of approximately one capillary for each muscle fibre in the ventricular walls and papillary muscles, and a less abundant supply in the auricular muscle and Purkinje system. The number of capillaries per sq. mm. of ventricular wall or papillary muscle is about twice that found by Krogh in skeletal muscle. Capillaries were not found constantly in the valves of hearts in which there was apparently a complete injection of the capillary bed. The method described for injecting the capillaries of the heart also provides a means of studying the blood supply to the muscle, valves and aortic wall in pathological hearts.  相似文献   
78.
A study of a malignant disease in rabbits has been made with reference to the presence or absence of a filterable virus, Virus III, in the tumor. The results are analyzed from the standpoint of certain characteristic features of the tumor process in order to determine any differences in degrees of malignancy. It was found that a more severe disease developed in the series in which the virus-bearing tumor was used than in the series in which the tumor was free of the virus, although the differences were not very marked and were not entirely constant. The influence of Virus III as a factor affecting malignancy has been discussed from the standpoint of its possible effect upon (α) the tumor cells and (b) the host reaction. It has been suggested that the greater malignancy of the pathological process usually induced by the virus-bearing tumor is attributable to a change in the response of the host to the tumor, which change is of the nature of a decreased resistance associated with the reaction of the host to the virus infection.  相似文献   
79.
Data from 645 normal rabbits were used as the basis of an investigation of the relation existing between body and organ weights. Actual and relative weights were correlated with both gross and net body weight. The results obtained varied with different classes of organs but it was found that, in general, there was an agreement between the form and degree of the correlation shown and the structural and functional properties of the organs concerned.  相似文献   
80.
A report is given of the results obtained by intratesticular inoculation of a malignant tumor of the rabbit based on a study of the first twenty generations. The subject is presented from the standpoint of variations in growth and malignancy as they occurred with continued transplantation. Essential features of the experimental conditions and of clinical and postmortem observations are condensed and recorded graphically. On analyzing the results of these experiments, it was found that many changes had occurred in the behavior of the tumor during transplantation, but that the changes were of a very irregular character and as a rule did not proceed constantly in any given direction. Moreover, the evidence as to the effect of transplantation on the growth and malignancy of the tumor was contradictory in that there was a great deal of evidence to show that there had been a decided increase in the activity and capacity for growth on the part of the tumor cells. But, with the exception of a few generations, there was an apparent reduction in the incidence and percentage distribution of secondary tumors, while the death rate was unaltered or actually diminished. It was believed that this paradoxical situation afforded a basis for an explanation of the results that had been obtained by transplantation.  相似文献   
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