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61.
Background
Yunnan province is located in south western China and is one of the poorest provinces of the country. This study examines the premature mortality burden from common causes of deaths among an urban region, suburban region and rural region of Kunming, the capital of Yunnan. 相似文献62.
H W Losken W M Morris P B Uys J W Earle P A Le Roux E Ackermann 《Suid-Afrikaanse tydskrif vir geneeskunde》1988,73(10):575-577
Trauma to the orbital region may result in fractures of the bony orbit, displacement of which gives rise to malposition of the eye and diplopia. If initial treatment is not feasible or is unsuccessful, later correction may be achieved by osteotomy or reduction and stabilisation of the bony fragments, often with bone grafts. Displaced medial or lateral canthi may need to be repositioned, where feasible in an overcorrected position. Where bone grafts are necessary, the skull is now favoured as the best donor site. 相似文献
63.
The authors report their experience of percutaneous nephrolithotomy over a period of three years. The analysis of the first 250 cases performed reveals a low morbidity, with serious complications in 1% of cases, and an acceptable complete success rate of 83%. The indications for percutaneous nephrolithotomy have been modified since the opening of an extracorporeal lithotripsy unit. The choice between the two techniques depends on their efficacy and their expected morbidity based on four criteria: the volume, chemical composition and site of the stone and the morphology of the upper urinary tract. Percutaneous nephrolithotomy is the treatment of choice for large stones (greater than 2.5 cm), hard stones or those formed proximally to a stenotic lesion of the urinary tract, which can then be dilated at the same procedure. A combination of the two methods is sometimes uses to treat staghorn calculi with a success rate of 80%. On the other hand, very large staghorn calculi with caliceal branches are best treated by open surgery. 相似文献
64.
V Le Gros P Escourrou H Nédelcoux C Gaultier 《Archives des maladies du coeur et des vaisseaux》1991,84(8):1127-1131
Sleep apnea syndrome and systemic hypertension are frequently associated but their causal relationship is unclear. We compared the oscillations of systemic blood pressure and heart rate during polysomnography in 8 normotensive subjects (2 females) and 5 hypertensive (supine awake blood pressure: 165 +/- 7/96 +/- 5 mmHg) without treatment. Their ages (normotensive: 52.1 +/- 11.0 yrs, hypertensive: 51.2 +/- 6.4 yrs) and body mass indices (32.6 +/- 9.6 kg/m2 vs 33.2 +/- 5.2 kg/m2 respectively) were not statistically different. Systemic blood pressure was continuously monitored by a non invasive digital plethysmography (Finapres). Both groups had similar respiratory events indices (normotensive: 45.2 +/- 18.1/hr, hypertensive: 48.4 +/- 20.5/hr) and minimal oxygen saturations (79.4 +/- 9.1% vs 82.4 +/- 7.0% respectively). During apneas in slow-wave sleep were observed the minimal values for systolic and diastolic pressures which were significantly higher in hypertensive than in normotensive (138.2 +/- 9.6/83.2 +/- 16.1 mmHg vs 105.9 +/- 11.1/60.5 +/- 10.9 mmHg respectively). During resumption of ventilation maximal blood values were recorded which were also higher in hypertensive than in normotensive (185.0 +/- 13.8/113.2 +/- 21.5 mmHg vs 155.9 +/- 19.8/88.7 +/- 17.1 mmHg respectively) (p less than 0.05). Although absolute variations of blood pressure were similar, relative changes in systolic pressure were significantly higher in normotensive (p less than 0.05). Maximal heart rate was 76.8 +/- 6.2 bpm in normotensive and 76.6 +/- 3.9 bpm in hypertensive during resumption of ventilation.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
65.
Hung Anh Nguyen Herv Cheradame Ernest Marchal 《Macromolecular chemistry and physics.》1992,193(9):2495-2503
The 1,3-dipolar addition of 2-azido-2,4,4-trimethylpentane ( 1 ) to acetylene and ethylene derivatives such as phenylacetylene (2), acrylonitrile, diphenyl fumarate ( 4 ) and N,N′-methylenebis(1,4-phenylene)dimaleimide ( 8 ) leads to the corresponding triazole and triazoline derivatives. This study demonstrates that tertiary azides are able to react with dienophiles, and the application of this reaction for the synthesis of block copolymers was investigated with monoazido-telechelic poly(2-methylpropene) (PMP). It was shown that the azido group is stable under the severe conditions of the polycondensation reaction without decomposition (170°C, 24 h), and the monoadduct PMP- 8 is produced with acceptable yield. 相似文献
66.
H M Blottière A Menoret C Burg J Y Douillard J Le Pendu 《International journal of cancer. Journal international du cancer》1992,50(2):315-320
Sera from BDIX rats inoculated with 2 tumor clones derived from a single syngeneic colon carcinoma were assayed by Western blotting for the presence of antibodies against the grafted tumor. The PROb clone is progressive and produces metastases. We observed that rats bearing this tumor developed antibodies against an unglycosylated water-soluble protein of 105 kDa. The magnitude of this humoral response, as assessed by the intensity of the signal on immunoblots, was inversely correlated with survival of the rats. Furthermore, rats inoculated with the REGb clone, which is immunologically rejected, never developed detectable antibodies against the tumor. Antisera from rats injected with PROb tumor detected p105 antigen in cellular extracts from the REGb clone and from a series of rat and human cell lines. This protein was also detected in variable amounts in some normal adult and fetal tissues. Treatment of PROb or REGb cells by either interferon-gamma or heat shock did not significantly alter the expression of the p105 auto-antigen. 相似文献
67.
OBJECTIVES: The objectives of this study were to verify the formation of a hydrolyzed surface layer on Duceram LFC, to determine the effects of such a layer on mechanical material properties, and to identify a specific mechanism responsible for any strength increase observed. METHODS: Specimens were fabricated from dentin porcelain by a vibration blotting technique and were prepared to have either blunt or sharp surface flaws. Half of the specimens underwent accelerated aging. Specimens were fractured in three-point flexure to measure their strength, and fractographic analysis was used to determine fracture toughness and residual surface stress. Surface hardness and elastic modulus were measured using a microindentation method. Porcelain surface topography was examined using atomic force microscopy, and Fourier transform infrared spectroscopy was used to determine the composition of the surface layer. RESULTS: The aging treatment modified the porcelain surface topography but did not create a layer with increased hydroxyl ion content. Porcelain strength increased upon aging, and the increase was proportional to initial flaw severity. The apparent fracture toughness of sharp flaw specimens increased to match that for specimens containing blunt flaws upon aging. Surface hardness and elastic modulus decreased upon aging. SIGNIFICANCE: Previous studies on the strength increase of hydrothermal porcelain were contradictory because a variety of specimen preparation procedures were used. This study resolves the apparent contradiction by determining the effect of specimen preparation on material strength. 相似文献
68.
69.
70.
DaniLe Brouty-Boye Dcspina Kolonias Theodore J. Lampidis 《International journal of cancer. Journal international du cancer》1995,60(4):571-575
The antiproliferative activity of the chemotherapeutic agent taxol was evaluated on 2 normal and 2 carcinoma human breast-cell lines and compared with its effects on newborn rat cardiac cells growing in vitro. Relatively little difference in ID50 response (ranging from 0.6 to 2.0 ng/ml) to taxol was found between normal and tumorous breast epithelial cells. Arrhythmias and slowing of beat frequencies of cardiac cells were induced by taxol but at doses approximately 10 times higher than those necessary to inhibit proliferation in dividing cells. Microtubules assayed by immunostaining appeared to be similarly retracted around the nucleus in both breast and heart cells. Overall, our results suggest that taxol does not selectively inhibit the growth of tumor vs. normal human breast cells. They also support the hypothesis that effects on microtubule integrity are associated with effects on cardiac function and that the clinical cardiac activity of taxol already reported may be due, at least in part, to a direct effect of taxol on cardiac cells as demonstrated in these in vitro studies. Thus, caution is needed, in view of possible cardiac effects, when using taxol in future clinical protocols, especially when combined with other cardioactive agents such as Adriamycin. 相似文献