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991.
We studied the incidence of regurgitation in 100 patients undergoing elective gynecological laparoscopies under general anesthesia with intermittent positive pressure ventilation using a laryngeal mask airway (LMA). Patients ingested methylene blue capsules 10-15 min before induction of anesthesia. After induction and insertion of an LMA using the recommended insertion technique, a fiberoptic examination of the larynx was made for traces of dye and to site a pH probe in the bowl of the LMA for continuous monitoring. LMA insertion was successful in all patients within two attempts (95 at first attempt). Fiberoptic examination revealed the vocal cords or cords and posterior or anterior epiglottis in 96 and no trace of dye in 99 patients. One patient regurgitated dye immediately after induction, and the stain was seen on the LMA after removal. The remaining 99 LMAs were not stained. Thirty patients were randomly selected for fiberoptic examination of the laryngopharynx before neuromuscular block was antagonized. Methylene blue staining did not occur in any of these patients. In 91 patients with complete pH data, regurgitation (pH < 4.0) did not occur. The 95% confidence limit for a true probability of regurgitation in this study is 0.041 or a true rate of regurgitation of less than 4.1%. A larger study would be required to possibly demonstrate a lower incidence of regurgitation. This study confirms the clinical impression that the incidence of regurgitation during laparoscopies with a LMA is extremely low. 相似文献
992.
N Brooks M Lee SR Wright S Woo S Centioni JA Hartley 《Canadian Metallurgical Quarterly》1997,12(7):591-606
In an attempt to produce additional alkylation and crosslinking in the minor groove of DNA, imidazole-containing analogs of distamycin were synthesized with benzoic acid mustard (BAM) and methoxyaziridinyl moieties present at the N- and C-termini, respectively. Analogs 1a-c differed in the number of methylene units (2-4 respectively) between the C-terminal carbonyl group and the methoxyaziridinyl moiety. DNA binding affinity to several polynucleotides decreased with increasing linker length, whereas DNA interstrand crosslinking ability, as measured by a plasmid gel based assay, increased. The in vitro cytotoxicity in human chronic myeloid leukemia K562 cells and the panel of human tumor cell lines at the National Cancer Institute decreased with increasing number of methylene units, and no increase in cytotoxicity was observed over compound AR-1-122 which did not contain the methoxyaziridinyl moiety. 1a-c had the same sequence selectivity of alkylation as AR-1-122, showing alkylation only at 5'-TTTTGPu sequences. The relative binding to these sequences decreased with increasing number of methylene units. The addition of a methoxyaziridinyl moiety in this group of imidazole and BAM-containing compounds can, therefore, increase crosslinking ability to naked DNA but this does not result in an increase in cytotoxicity. In contrast the cytotoxicity was related to their ability to produce sequence specific alkylation at 5'-TTTTGPu sequences. 相似文献
993.
JA van der Vliet WN van Asten JH Haenen AP Boll FG Buskens 《Canadian Metallurgical Quarterly》1997,16(8):525-528
Adequate patient selection is required to limit the clinical workload and improve the cost-effectiveness of noninvasive hemodynamic evaluation of the aortoiliac system. In a prospective blinded fashion the traditional invasive technique of direct femoral artery pressure measurements and the computerized Doppler spectrum analysis of blood flow velocities in the common femoral artery were studied. Both tests for rapid assessment of aortoiliac obstruction were compared with duplex ultrasonographic imaging, using a peak systolic velocity ratio of 2.5 to demonstrate stenoses of 50% or more. In a series of 17 consecutive patients (34 aortoiliac segments) with suspected aortoiliac obstructive disease, a good level of agreement (kappa = 0.6) was found for both methods when compared with duplex scanning. Analysis of deviations from the duplex registrations indicated an overestimation of the pathologic cases using femoral artery pressure measurements and an underestimation using Doppler spectrum analysis of blood flow velocities in the common femoral artery. Both methods were well tolerated, but femoral artery pressure measurements had a higher technical failure rate. Because of its noninvasive character and its feasibility the Doppler technique is preferred for the selection of patients for more extensive duplex sonographic investigation. 相似文献
994.
Fetal alcohol syndrome (FAS) is characterized in part by mental impairment, as well as craniofacial and ocular anomalies. These conditions are traditionally associated with childhood hearing disorders, because they all have a common embryonic origin in malformations of the first and second branchial arches, and have similar critical periods of vulnerability to toxic insult. A review of human and animal research indicates that there are four types of hearing disorders associated with FAS. These are: (1) a developmental delay in auditory maturation, (2) sensorineural hearing loss, (3) intermittent conductive hearing loss due to recurrent serous otitis media, and (4) central hearing loss. The auditory and vestibular systems share the same peripheral apparatuses (the inner ear and eighth cranial nerve) and are embryologically and structurally similar. Consequently, vestibular disorders in FAS children might be expected. The evidence for vestibular dysfunction in FAS is ambiguous, however. Like other syndromes associated with craniofacial anomalies, hearing disorders, and mental impairment, FAS is also characterized by a high prevalence of speech and language pathology. Hearing disorders are a form of sensory deprivation. If present during early childhood, they can result in permanent hearing, language, and mental impairment. Early identification and intervention to treat hearing, language, and speech disorders could therefore result in improved outcome for the FAS child. Specific recommendations are made for intervention and future research. 相似文献
995.
JA Biegel AJ Janss C Raffel L Sutton LB Rorke JM Harper PC Phillips 《Canadian Metallurgical Quarterly》1997,3(3):473-478
Until fairly recently, investigations into the control of cell production (proliferation) have been the mainstay of studies into the maintenance of mucosal homeostasis and general integrity. However, in addition to proliferation, it is now increasingly evident that programmed cell death, specifically that form of programmed cell death known as apoptosis, is an equally, if not more important, mechanism of regulating mucosal cell number. This review will concentrate on the significance of damage (radiation) induced and spontaneous apoptosis in the maintenance of intestinal epithelial stem cell number and integrity, and its probable link to the level of cancer incidence in the small intestine and colon. 相似文献
996.
JH Lin M Chiba IW Chen KJ Vastag JA Nishime BD Dorsey SR Michelson SL McDaniel 《Canadian Metallurgical Quarterly》1995,274(1):264-269
L-754,394 is a potent and specific inhibitor of the HIV-1 encoded protease that is essential for the maturation of the infectious virus. The drug exhibited dose-dependent kinetics in all species studied (rat, dog and monkey); the apparent clearance decreased when the dose was increased. However, the dose-dependency cannot be explained by Michaelis-Menten kinetics. L-754,394 in plasma declined log-linearly with time, but with an apparent half-life that increased with dose. The apparent terminal half-life of L-754,394 in rats increased from 20 min at 0.5 mg/kg i.v. to 118 min at 10 mg/kg i.v. Furthermore, L-754,394 exhibited time-dependent pharmacokinetics. After chronic i.v. doses for 7 days (1 mg/kg/dose/day), the apparent clearance of L-754,394 in rats decreased from 87 ml/min/kg after the first dose to 25 ml/min/kg after the last dose. Similar results were observed in dogs and monkeys. In vitro spectral studies indicated that approximately 40 to 60% of the content of cytochrome P-450 was inactivated when L-754,394 (10 microM) was incubated with rat, dog and monkey liver microsomes in the presence of NADPH. Little or no inactivation of cytochrome P-450 was observed when either NADPH or L-754,394 was omitted. In addition, L-754,394 selectively inhibited CYP 2C11-dependent testosterone 2 alpha- and 16 alpha-hydroxylase activity and CYP 3A1/2-dependent testosterone 6 beta-hydroxylase activity, but not CYP 2D1/2-dependent bufuralol 1'-hydroxylase activity nor CYP 1A2-dependent phenacetin O-deethylase activity in rat liver microsomes.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
997.
998.
999.
Breast cancer is a major cause of morbidity and mortality in women in many parts of the world. Breast carcinomas are heterogenous in their biological and clinical behaviour and a greater understanding of how they develop and progress could lead to more directed forms of screening and therapy. It is important to determine the molecular mechanisms underlying the natural history of breast cancer. Developments in the techniques for molecular analysis have meant that they can now be applied to a large range of clinical material such as cytological preparations and fixed, embedded material, so increasing the potential for relating any molecular alterations to clinical behaviour and response to therapy. In this review we consider recent developments in three areas of importance to breast cancer; genetic analysis-oncogenes, tumour suppressor genes, loss of heterozygosity, microsatellite instability, familial breast cancer; steroid receptors, oestrogen regulated proteins, epidermal growth factor receptor, growth factors particularly transforming growth factor beta; and cell adhesion, invasion and metastasis-E-cadherin, integrins, proteases. These are discussed in relation to potential for screening, prognosis and treatment. 相似文献
1000.
GA Macones HM Sehdev S Parry MA Morgan JA Berlin 《Canadian Metallurgical Quarterly》1997,177(5):1097-1100
We compared various diagnostic tests for their abilities to detect Mycobacterium ulcerans infection in specimens from patients with clinically active disease. Specimens from 10 patients from the area of Zangnanado (Department of Zou, Benin) with advanced, ulcerated active M. ulcerans infections were studied by direct smear, histopathology, culture, PCR, and oligonucleotide-specific capture plate hybridization (OSCPH). A total of 27 specimens, including 12 swabs of exudate collected before debridement and 15 fragments of tissue obtained during debridement, were submitted to bacteriologic and histopathologic analysis. The histopathologic evaluation of tissues from all six patients so tested revealed changes typical of those caused by M. ulcerans infection. Five specimens were contaminated, and M. ulcerans was cultivated on L?wenstein-Jensen medium from 12 of the remaining 22 (54.5%) specimens. Detection of mycobacteria was performed by PCR, and M. ulcerans was detected by OSCPH with a new probe (5'-CACGGGATTCATGTCCTGT-3') reacting with M. ulcerans and Mycobacterium marinum. In 10 of 22 (45.5%) specimens, M. ulcerans was identified by PCR-OSCPH. There was no statistically significant difference between the detection of M. ulcerans by culture and by PCR-OSCPH (P > 0.05). This is the first demonstration of an amplification system (PCR-OSCPH) with a sensitivity similar to that of culture for the direct and rapid recognition of M. ulcerans in clinical specimens. This system is capable of identifying M. ulcerans, even in paucibacillary lesions. Our findings suggest that PCR-OSCPH should be used in the quest for the elusive environmental reservoir(s) of M. ulcerans. 相似文献