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Because no large series of perforated peptic ulcers has been reported from Canada, 402 cases from the Ottawa Civic Hospital were reviewed to study this dramatic disorder.The incidence was 15 per 100,000 population annually, or one in every 1000 hospital admissions.The incidence in females and the elderly in this series was higher than reported elsewhere. The risk of perforation increased with age, being greatest after 55; this was not due to an excess of chronic ulcers in older patients, indicating that ageing is an etiological factor.As the mortality of perforated peptic ulcer—20%—had remained unchanged over the years, fatal cases were studied to see if changes should be made in the management of this condition. The mortality for patients undergoing operation was 7.5%. Patients treated conservatively because their general condition was poor, died. Fifteen patients, in whom an incorrect diagnosis was made, died. More aggressive therapy and greater efforts at diagnosis might have saved some of these patients. 相似文献
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Summary The quantitative growth of Pseudococcomyxa adhaerens on glass cover slips in distilled water has been studied. Growth is limited by the supply of inorganic nutrients. Regular replacement of the distilled water gives an increase in the growth rate. The light intensity for maximum growth is a function of the nutrient supply. In a culture solution the rate of growth is about 8 times as great as in distilled water, and the limiting light intensity is increased to 400 lux from 100 lux. 相似文献
96.
J. L. Taylor 《The Australian journal of anthropology》1989,19(2):112-125
This paper is concerned with the ongoing intense interest in Thailand of two controversial urban Buddhist movements which have appeared since the beginning of the seventies, Santi Asok and Thammakaai. Essentially, I view both as a resonance of the perceived need for ‘change’ among an articulate aspiring new middle class. I also argue that both Santi Asok and Thammakaai in their expressions — Thammakaai the specious discursive function of capital, Santi Asok by confrontation and spurning what they consider an ‘amoralistic’ establishment — are predicating a radical critique of the Thai social order, a call for collective ‘inner-worldly activism’ and ‘individualistic’ reflexive response to convention. 相似文献
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98.
Cervical cancer screening and demonstration projects to identify barriers to optimal screening are discussed. Interview surveys showed that older women and women in low-income groups tended to have lower rates of Papanicolaou smear screening. Data produced by demonstration projects established by the Centers for Disease Control in collaboration with state and local authorities and private institutions will be used to design and implement strategies for increasing screening levels to further reduce cervical cancer mortality. 相似文献
99.
Twenty-seven adipocyte-specific, cell surface-exposed proteins were detected by derivatizing undifferentiated and differentiated 3T3-L1 cells with membrane impermeant sulfosuccinimidyl 2-(biotinamido)ethyl-1,3-dithiopropionate at 0 degrees C. Biotinylated proteins were adsorbed onto streptavidin-agarose, resolved on two-dimensional polyacrylamide gels, and detected by autoradiography or silver staining. Of the surface-exposed proteins specific to adipocytes, three were phosphorylated and seven were glycoproteins that bound to wheat germ agglutinin and eluted with N-acetylglucosamine. Eleven of the adipocyte-specific proteins were bound to streptavidin-agarose after the cells were biotinylated at 20 degrees C and then stripped with glutathione at 0 degrees C to isolate plasma membrane proteins that localize to recycling endosomes as well as the cell surface. When insulin-deprived cells were acutely treated with insulin, only a few proteins, including one protein tentatively identified as the GLUT4 glucose transporter, were found to increase in concentration at the cell surface. These latter results imply that up-regulation of glucose transport by the translocation of GLUT4 to the cell surface in response to insulin occurs by exocytic fusion of an intracellular compartment having a limited number of proteins. 相似文献
100.
Thomas N. Taylor Georgina M. Del Fueyo Edith L. Taylor 《American journal of botany》1994,81(6):666-677
In this paper we describe the first anatomically preserved Mesozoic seed fern cupule–Petriellaea. The multiovulate cupules were produced singly at the end of a short dichotomizing axis. Cupules are bilateral with a dorsal groove and transverse narrow ventral opening. The vascular system of the cupule consists of a series of traces that extend up the dorsal surface of the cupule and down the ventral face. Ovules are orthotropus, sessile, and borne on the adaxial surface of the leaflike cupule either singly or in multiple rows. They are up to 1.5 mm long, triangular in transverse section, and characterized by a multilayered integument. Nucellus and integument are fused throughout their length, but no pollen chamber is present. In the chalaza is a small vascular disc of transfusion tracheids that represents the extent of the ovule vascular system. Ovules are interpreted as being fossilized at a prepollination stage, although a few possess some evidence of a cellularized megagametophyte. These permineralized cupules indicate that in at least one Mesozoic seed fern group, ovule enclosure resulted from the transverse folding (tip to petiole) of a megasporophyll bearing adaxial ovules. Cupule morphology and ovule enclosure in other Late Paleozoic and Mesozoic seed ferns is discussed. 相似文献