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991.
992.
MD Holmes SM Safyer NA Bickell SH Vermund PA Hanff RS Phillips 《Canadian Metallurgical Quarterly》1993,83(4):551-555
OBJECTIVES: The prevalence of Chlamydia trachomatis cervical infection in incarcerated adult women has not been reported. To develop a policy for testing and treatment, we determined the prevalence of and risk factors for chlamydial infection in women in a New York City jail. METHODS: Interviews and cervical cultures for C trachomatis were obtained from 101 consenting female inmates. RESULTS: Positive cultures for C trachomatis were found in 27% of the participants. Mucopurulent cervical discharge and education of 8 years or less were two independent risk factors for infection, but only 63% of the infected women had one or both of these factors. If pelvic tenderness were considered as a third factor, an additional 7% of the infected women would have been identified. CONCLUSIONS: The prevalence of chlamydial infection in this population was as high as that in populations for which presumptive treatment is recommended. Although the optimal policy for detection and treatment of chlamydial infection may vary depending on practical considerations, we suggest that women entering correctional facilities should be screened or offered presumptive therapy for C trachomatis infection. 相似文献
993.
994.
NA Martin RV Patwardhan MJ Alexander CZ Africk JH Lee E Shalmon DA Hovda DP Becker 《Canadian Metallurgical Quarterly》1997,87(1):9-19
The extent and timing of posttraumatic cerebral hemodynamic disturbances have significant implications for the monitoring and treatment of patients with head injury. This prospective study of cerebral blood flow (CBF) (measured using 133Xe clearance) and transcranial Doppler (TCD) measurements in 125 patients with severe head trauma has defined three distinct hemodynamic phases during the first 2 weeks after injury. The phases are further characterized by measurements of cerebral arteriovenous oxygen difference (AVDO[2]) and cerebral metabolic rate of oxygen (CMRO[2]). Phase I (hypoperfusion phase) occurs on the day of injury (Day 0) and is defined by a low CBF calculated from cerebral clearance curves integrated to 15 minutes (mean CBF 32.3 +/- 2 ml/100 g/minute), normal middle cerebral artery (MCA) velocity (mean V[MCA] 56.7 +/- 2.9 cm/second), normal hemispheric index ([HI], mean HI 1.67 +/- 0.11), and normal AVDO(2) (mean AVDO[2] 5.4 +/- 0.5 vol%). The CMRO, is approximately 50% of normal (mean CMRO(2) 1.77 +/- 0.18 ml/100 g/minute) during this phase and remains depressed during the second and third phases. In Phase II (hyperemia phase, Days 1-3), CBF increases (46.8 +/- 3 ml/100 g/minute), AVDO(2) falls (3.8 +/- 0.1 vol%), V(MCA) rises (86 +/- 3.7 cm/second), and the HI remains less than 3 (2.41 +/- 0.1). In Phase III (vasospasm phase, Days 4-15), there is a fall in CBF (35.7 +/- 3.8 ml/100 g/minute), a further increase in V(MCA) (96.7 +/- 6.3 cm/second), and a pronounced rise in the HI (2.87 +/- 0.22). This is the first study in which CBF, metabolic, and TCD measurements are combined to define the characteristics and time courses of, and to suggest etiological factors for, the distinct cerebral hemodynamic phases that occur after severe craniocerebral trauma. This research is consistent with and builds on the findings of previous investigations and may provide a useful temporal framework for the organization of existing knowledge regarding posttraumatic cerebrovascular and metabolic pathophysiology. 相似文献
995.
996.
AP Spicer MF Seldin AS Olsen N Brown DE Wells NA Doggett N Itano K Kimata J Inazawa JA McDonald 《Canadian Metallurgical Quarterly》1997,41(3):493-497
We have recently identified a new vertebrate gene family encoding putative hyaluronan (HA) synthases. Three highly conserved related genes have been identified, designated HAS1, HAS2, and HAS3 in humans and Has1, Has2, and Has3 in the mouse. All three genes encode predicted plasma membrane proteins with multiple transmembrane domains and approximately 25% amino acid sequence identity to the Streptococcus pyogenes HA synthase, HasA. Furthermore, expression of any one HAS gene in transfected mammalian cells leads to high levels of HA biosynthesis. We now report the chromosomal localization of the three HAS genes in human and in mouse. The genes localized to three different positions within both the human and the mouse genomes. HAS1 was localized to the human chromosome 19q13.3-q13.4 boundary and Has1 to mouse Chr 17.HAS2 was localized to human chromosome 8q24.12 and Has2 to mouse Chr 15. HAS3 was localized to human chromosome 16q22.1 and Has3 to mouse Chr 8. The map position for HAS1 reinforces the recently reported relationship between a small region of human chromosome 19q and proximal mouse chromosome 17. HAS2 mapped outside the predicted critical region delineated for the Langer-Giedion syndrome and can thus be excluded as a candidate gene for this genetic syndrome. 相似文献
997.
998.
Basing on the results of their studies, analysis of 894 patients with tuberculosis of the lymph nodes and nonspecific lymphadenopathy treated in 1983-1993, medical literature, the authors investigate the place of lymphadenopathies in medical practice: new data on the patients, pathogenesis and pathomorphosis of tuberculous and nonspecific lymphadenopathies, diagnostic techniques. Updated approaches to this disease led to a 17.8% decrease in the percentage of cases with unclear etiology. 相似文献
999.
PVC残留VC脱除方法的技术改进 总被引:2,自引:0,他引:2
论述了在PVC生产过程中残留VC脱除方法,并对真空汽提法、热真空抽提法的工艺及操作优缺点进行了分析比较,通过技术经济评价,最后确定了热真空抽提法为中型PVC树脂生产企业脱除残留VC的最佳工艺方法。 相似文献
1000.
Destruction of the membranous labyrinth can lead to sensorineural hearing loss. This is especially frequent in surgery for active otorrhea. However, destruction of the posterior labyrinth sometimes can be solved without loss of cochlear function. We report three cases of partial labyrinthectomy for intralabyrinthine cholesteatoma without functional loss. Current theories regarding the conservation of hearing are discussed. 相似文献