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111.
A Trupka C Waydhas KK Hallfeldt D Nast-Kolb KJ Pfeifer L Schweiberer 《Canadian Metallurgical Quarterly》1997,43(3):405-11; discussion 411-2
OBJECTIVE: The aim of this prospective study was to evaluate whether early thoracic computed tomography (TCT) is superior to routine chest x-ray (CXR) in the diagnostic work-up of blunt thoracic trauma and whether the additional information influences subsequent therapeutic decisions on the early management of severely injured patients. PATIENTS AND METHODS: In a prospective study of 103 consecutive patients with clinical or radiologic signs of chest trauma (94 multiple injured patients with chest trauma, nine patients with isolated chest trauma), an average Injury Severity Score of 30 and an average Abbreviated Injury Scale thorax score of 3, initial CXR and TCT were compared after initial assessment in our emergency department of a Level I trauma center. RESULTS: In 67 patients (65%) TCT detected major chest trauma complications that have been missed on CXR (lung contusion (n = 33), pneumothorax (n = 27), residual pneumothorax after chest tube placement (n = 7), hemothorax (n = 21), displaced chest tube (n = 5), diaphragmatic rupture (n = 2), myocardial rupture (n = 1)). In 11 patients only minor additional pathologic findings (dystelectasis, small pleural effusion) were visualized on TCT, and in 14 patients CXR and TCT showed the same pathologic results. Eleven patients underwent both CXR and TCT without pathologic fundings. The TCT scan was significantly more effective than routine CXR in detecting lung contusions (p < 0.001), pneumothorax (p < 0.005), and hemothorax (p < 0.05). In 42 patients (41%) the additional TCT findings resulted in a change of therapy: chest tube placement, chest tube correction of pneumothoraces or large hemothoraces (n = 31), change in mode of ventilation and respiratory care (n = 14), influence on the management of fracture stabilization (n = 12), laparotomy in cases of diaphragmatic lacerations (n = 2), bronchoscopy for atelectasis (n = 2), exclusion of aortic rupture (n = 2), endotracheal intubation (n = 1), and pericardiocentesis (n = 1). To evaluate the efficacy of all those therapeutic changes after TCT the rates of respiratory failure, adult respiratory distress syndrome, and mortality in the subgroup of patients with Abbreviated Injury Scale thorax score of > 2 were compared with a historical control group, consisting of 84 patients with multiple trauma and with blunt chest trauma Abbreviated Injury Scale thorax score of > 2, prospectively studied between 1986 and 1992. Age (38 vs. 39 years), average Injury Severity Score (33 vs. 38), and the rate of respiratory failure (36 vs. 56%) were not statistically different between the two groups, but the rates of adult respiratory distress syndrome (8 vs. 20%; p < 0.05) and mortality (10 vs. 21%; p < 0.05) were significantly reduced in the TCT group. CONCLUSIONS: TCT is highly sensitive in detecting thoracic injuries after blunt chest trauma and is superior to routine CXR in visualzing lung contusions, pneumothorax, and hemothorax. Early TCT influences therapeutic management in a significant number of patients. We therefore recommend TCT in the initial diagnostic work-up of patients with multiple injuries and with suspected chest trauma because early and exact diagnosis of all thoracic injuries along with sufficient therapeutic consequences may reduce complications and improve outcome of severely injured patients with blunt chest trauma. 相似文献
112.
FM Hecht J Wheat AH Korzun R Hafner KJ Skahan R Larsen MT Limjoco M Simpson D Schneider MC Keefer R Clark KK Lai JM Jacobson K Squires JA Bartlett W Powderly 《Canadian Metallurgical Quarterly》1997,16(2):100-107
The expression of cytokeratins (CKs) in normal cervical epithelium, low grade squamous intraepithelial lesions (SIL), high grade SILs and squamous cell carcinoma (SCC) were analyzed using four different monoclonal antikeratin antibodies. In normal cervical epithelium, CK 18 showed strong immunoreactivity in basal and parabasal layers. CK 19 and 14 were expressed only in the basal layer while CK 13 was found selectively n the spinal cells. As the lesions progressed from low grade SIL to high grade SIL, immunoreactivity of CK 18, 19 and 14 in the basal cell compartment increased while the expression of CK 13 decreased. In SCC, as well-differentiated tumors showed decreased immunoreactivity for CK 18, 19 and 14 with CK 13 showing a strong and focal (localized) immunoreactivity. Undifferentiated carcinomas totally lacked CK 13 reactivity. Our findings therefore suggest that expression of CK 18, 19 and 14 may be directly related to tumor grade and CK 13 may be a marker of differentiation in cervical lesions. 相似文献
113.
114.
JT Kuikka KK Akerman J Hiltunen KA Bergstr?m P R?s?nen E Vanninen C Halldin J Tiihonen 《Canadian Metallurgical Quarterly》1997,24(5):483-487
The complete sequence of a 36775 bp DNA segment located on the right arm of chromosome XV of Saccharomyces cerevisiae has been determined and analysed. The sequence encodes 26 open reading frames of at least 100 amino acids. Eight of these correspond to known genes, whereas 18 correspond to new genes. 相似文献
115.
PB Jacobsen MR Widows DM Hann MA Andrykowski LE Kronish KK Fields 《Canadian Metallurgical Quarterly》1998,60(3):366-371
Hormonal treatments which have an androgenic effect have the potential to cause vocal changes. The changes in vocal fold structure and voice quality are considered to be irreversible. To date, studies have documented subjective vocal changes or documented single cases without detailed, baseline voice assessments. The impact on laryngeal function of women taking these androgenic treatments requires further detailed, objective assessment. The need for increased awareness of the actions of androgenic hormones on womens' voices, and the benefits of a thorough voice assessment are discussed. 相似文献
116.
Our objective was to test the hypothesis that short-term (8 days) treatment of prepubertal heifers with melengestrol acetate (MGA) and subsequent steroid withdrawal would stimulate LH secretion and follicular growth. Angus heifers were divided randomly into two groups; MGA-treated (n = 8) or control (CON; n = 9). Puberty was determined by monitoring circulating concentrations of progesterone and ovarian morphology during a 14-day period following MGA withdrawal. LH secretory patterns were assessed upon initiation of MGA (Day 0), during MGA (Day 7), and 1 day after withdrawal of MGA (Day 9). All MGA-treated heifers, versus four CON heifers, exhibited corpora lutea and luteal phase concentrations of progesterone within 10 days after treatment (p = 0.01). Mean LH and LH pulse frequency increased (p = 0.005 and 0.0001, respectively) between Days 0 and 9 in MGA-treated heifers. In CON heifers, mean LH concentrations and pulse frequencies did not change. During the same period, diameter of the largest follicle increased in MGA-treated animals (p = 0.003) but did not change in the CON heifers. On the basis of these results, we suggest that MGA withdrawal enhances onset of puberty by stimulating pulsatile LH secretion that accelerates follicle growth to the preovulatory stage. 相似文献
117.
This is a retrospective study on the prevalence of diverticulosis in Hong Kong Chinese adults. Eight-hundred and fifty-eight consecutive barium enema examinations over a period of 18 months (January 1995-June 1996) were analysed. Results show that the prevalence of diverticulosis in our community is 25.1% with no significant difference between male and female adults. The prevalence is lower than Western countries but higher than in Asia. Moreover, the peak prevalence is at the 50-79 years age group with lower prevalence in the older age groups. This may be explained by the rapid rise in prevalence in the younger age groups so that the age-related increase in prevalence become obscured. We postulate that this may be due to Western cultural influence in our diet and lifestyle. There is no significant difference in the symptomatology of patients with and without diverticulosis, supporting the idea that diverticulosis alone is usually asymptomatic. There is predominance of right hemicolon involvement in our subjects, in contrast to the left hemicolon predominance in the Caucasian population. Of patients with diverticulosis, 55.3% have only right-sided involvement and 32.6% have bilateral involvement. Only 12.1% of patients with diverticulosis have exclusively left hemicolon involvement. Caecal and ascending colon diverticula are found in 6.4% and 17.6% of all the adults under study, respectively. Clinicians caring for patients from our community should take note of this high frequency of caecal and ascending colon diverticulosis as caecal and ascending colon diverticulitis is notoriously difficult to diagnose clinically. 相似文献
118.
DF Becker U Leartsakulpanich KK Surerus JG Ferry SW Ragsdale 《Canadian Metallurgical Quarterly》1998,273(41):26462-26469
An iron-sulfur flavoprotein (Isf) from the methanoarchaeaon Methanosarcina thermophila, which participates in electron transfer reactions required for the fermentation of acetate to methane, was characterized by electrochemistry and EPR and M?ssbauer spectroscopy. The midpoint potential (Em) of the FMN/FMNH2 couple was -0.277 V. No flavin semiquinone was observed during potentiometric titrations; however, low amounts of the radical were observed when Isf was quickly frozen after reaction with CO and the CO dehydrogenase/acetyl-CoA synthase complex from M. thermophila. Isf contained a [4Fe-4S]2+/1+ cluster with g values of 2.06 and 1.93 and an unusual split signal with g values at 1.86 and 1.82. The unusual morphology was attributed to microheterogeneity among Isf molecules. The Em value for the 2+/1+ redox couple of the cluster was -0.394 V. Extracts from H2-CO2-grown Methanobacterium thermoautotrophicum cells catalyzed either the H2- or CO-dependent reduction of M. thermophila Isf. In addition, Isf homologs were found in the genomic sequences of the CO2-reducing methanoarchaea M. thermoautotrophicum and Methanococcus jannaschii. These results support a general role for Isf in electron transfer reactions of both acetate-fermenting and CO2-reducing methanoarchaea. It is suggested that Isf functions to couple electron transfer from ferredoxin to membrane-bound electron carriers, such as methanophenazine and/or b-type cytochromes. 相似文献
119.
Two experiments examined how cognitive resources are allocated to comprehension processes across two readings of the same scientific texts. In Experiment 1, readers read and later reread texts describing scientific topics. The results indicated that across readings, readers decreased resources allocated to proposition assembly, increased resources allocated to text-level integration, and expended a similar amount of resources to lexical access. Subjects who reread the texts after a week delay showed a similar pattern, except that they did not show the increase for text-level integration. Experiment 2 revealed a similar pattern of results with a moving window procedure, except that there was a significant decrease in resources allocated to lexical access across exposures. This experiment also indicated that the rereading speedup was greatest at sentence boundaries, suggesting that the prior exposure enabled readers to immediately process each word. Overall, the results are consistent with the claim that readers allocate proportionally more available resources to text-level integration during rereading because proposition assembly, which enables text-level integration, can be completed with fewer resources. 相似文献
120.
JE Cobb SG Blanchard EG Boswell KK Brown PS Charifson JP Cooper JL Collins M Dezube BR Henke EA Hull-Ryde DH Lake JM Lenhard W Oliver J Oplinger M Pentti DJ Parks KD Plunket WQ Tong 《Canadian Metallurgical Quarterly》1998,41(25):5055-5069
3-?4-[2-(Benzoxazol-2-ylmethylamino)ethoxy]phenyl?-(2S)-((2- benzoylph enyl)amino)propionic acid (1) and (2S)-((2-benzoylphenyl)amino)-3-?4-[2-(5-methyl-2-phenyloxazol-4-y l)e thoxy]phenyl?propionic acid (2) are peroxisome proliferator-activated receptor gamma (PPARgamma) agonists and have antidiabetic activity in rodent models of type 2 diabetes. As part of an effort to develop the SAR of the N-2-benzoylphenyl moiety of 1 and 2, a series of novel carboxylic acid analogues, 23-66, modified only in the N-2-benzoylphenyl moiety were synthesized from L-tyrosine and evaluated as PPARgamma agonists. In general, only modest changes in the N-2-benzoylphenyl moiety of 1 and 2 are tolerated. More specifically, the best changes involve bioisosteric replacement of one of the two phenyl rings of this moiety. Addition of substituents to this moiety generally produced compounds that are less active in the cell-based functional assays of PPARgamma activity although binding affinity to PPARgamma may be maintained. A particularly promising set of analogues is the anthranilic acid esters 63-66 in which the phenyl ring in the 2-benzoyl group of 1 and 2 has been replaced by an alkoxy group. In particular, (S)-2-(1-carboxy-2-?4-[2-(5-methyl-2-phenyloxazol-4-yl)ethoxy]phen yl? ethylamino)benzoic acid methyl ester (63) has a pKi of 8.43 in the binding assay using human PPARgamma ligand binding domain and a pEC50 of 9.21 in the in vitro murine lipogenesis functional assay of PPARgamma activity. Finally, 63 was found to normalize glycemia when dosed at 3 mg/kg bid po in the Zucker diabetic fatty rat model of type 2 diabetes. 相似文献