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941.
942.
J E Boyd P Collings P M Crofton G Blundell J M Davis 《Occupational and environmental medicine》1984,41(4):455-458
Alpha 1 antitrypsin (alpha 1 AT) serum concentration was determined for a group of coalminers with particularly low levels of lung function, not thought to be explicable in terms of age and dust exposure, and compared with two other groups of coalminers who had average or above average lung function. There was no evidence for an alpha 1 AT deficiency in coalminers with poor lung function. On the contrary, a reactionary increase was evident, even in non-smokers, which may have resulted from the high frequency of chest disease in these men. Within the non-smoking group men with poor lung function had been exposed to higher mean levels of dust, and a greater proportion had early signs of bronchitis. There was no indication that the presence or degree of pneumoconiosis was affecting the results. 相似文献
943.
The study evaluated the effect of increasing the amount of rinse solution upon the concentration of chlorhexidine needed to control plaque formation, compared the application of chlorhexidine with an oral irrigator to normal rinsing, and examined the amount of staining caused by the various dosages. Forty-four dental students were divided into 7 groups which each used different volumes (700, 400, 200, applied with an oral irrigator and 200, 100, 50 and 20 ml used with normal rinsing). On a rotational basis, the individuals tested all concentrations (0, .01, .025, .05, .075, .1, .15 and .2 per cent) once during each 9 day test period of suspended oral hygiene. The plaqoe accumulation was. assessed at the end of each trial period according to the criteria of the Plaque Index system. Each lest period was separated by 5 days of normal oral hygiene. The study has shown that if larger volumes are used much lower concentrations of chlorhexidine are necessary, plaque inhibition in the posterior portion of the oral cavity is better with an irrigator than with normal rinsing and that staining is less with large volumes of dilute concentrations than with small volumes of stronger concentrations. 相似文献
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Since the establishment of extracorporeal shock wave lithotripsy for the treatment of upper urinary tract calculi, further potential applications have been explored. We report the successful use of extracorporeal shock wave lithotripsy for the treatment of obstructive calculi on staples within the afferent nipple of a Kock pouch ureteroileal urinary diversion. 相似文献
947.
Detectable levels (greater than or equal to 0.2 pmol/10(6) cells) of one or more prostanoid species resultant to calcium ionophore A23187-induced biosynthesis from endogenous arachidonic acid were distributed in 28 cell lines derived from different histological classes of lung tumors as follows: large cell undifferentiated carcinoma (3 of 3 cell lines); adenosquamous carcinoma (1 of 2 cell lines); squamous cell carcinoma (0 of 2 cell lines); adenocarcinoma (9 of 10 cell lines); bronchioloalveolar cell carcinoma (2 of 2 cell lines); and small cell carcinoma (1 of 9 cell lines). Using the mean levels of 9 alpha,11 beta-prostaglandin F2, prostaglandin F2 alpha, prostaglandin D2, prostaglandin E2, thromboxane B2 and 6-keto-prostaglandin F1 alpha as an index of prostaglandin H (PGH) synthase activity, the distribution in cell lines representative of the different histological classes of human lung tumors exhibiting PGH synthase activity exceeding mean values greater than or equal to 2 pmol/10(6) cells was as follows: large cell undifferentiated carcinoma (3 of 3 cell lines), adenosquamous carcinoma (1 of 2 cell lines), adenocarcinoma (8 of 10) cell lines), bronchioloalveolar cell carcinoma (2 of 2 cell lines) and small cell carcinoma (0 of 9 cell lines). Three different prostanoid species accumulated to mean levels greater than or equal to 2 pmol/10(6) cells. Prostaglandin E2 levels exceeded 2 pmol/10(6) cells in 14 of the 16 cell lines in which this prostanoid accumulated to detectable levels. Cumulative levels of prostaglandin F2 alpha exceeded 2 pmol/10(6) cells in 9 of the 15 cell lines in which prostaglandin F2 alpha reached detectable levels. Detectable levels of thromboxane B2 were observed in five cell lines with thromboxane B2 accumulation exceeding 2 pmol/10(6) cells in two of the five cell lines. 9 alpha,11 beta-prostaglandin F2 and 6-keto-prostaglandin F1 alpha accumulated to detectable levels in the culture medium of one cell line, while prostaglandin D2 accumulation to detectable levels was observed in two cell lines. Stimulation of cultured human lung tumor cells exhibiting PGH synthase activity greater than or equal to 2 pmol/10(6) cells in the presence of 10(-5) M exogenous arachidonic acid resulted in a 2- to 4-fold increase in the accumulation of individual prostanoids, while the inclusion of a 10(-5) M exogenous concentration of arachidonic acid failed to stimulate detectable prostanoid production in human lung tumor cells in which PGH synthase activity was not previously expressed.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
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950.
It is now well established that structural changes in resistance vessels contribute to the long-term maintenance of many forms of hypertension. This study measured the time course of structural change in smaller resistance vessels during the development of deoxycorticosterone acetates (DOCA) hypertension and after cessation of DOCA in Wistar rats by histometric assessment of cross-sections of renal arterioles. The relationship of structural change to blood pressure was assessed by preventing hypertension during DOCA treatment with hydralazine. Blood pressure rose progressively during DOCA treatment reaching 192 +/- 3 mmHg compared with 132 +/- 2 mmHg in controls after 10 weeks. Five and 10 weeks after cessation of DOCA, following 10 weeks of DOCA treatment, post-DOCA reversal of hypertension was only partial. Medial area to internal elastic lamina (IEL) radius ratio, wall to lumen ratio and intimal area to IEL radius ratio of renal arterioles increased progressively during 10 weeks of DOCA treatment with partial reversal of the increased medial area and wall to lumen ratio 5 weeks post-DOCA. Hydralazine completely prevented hypertension in DOCA rats and also largely prevented structural change. 相似文献