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61.
Neuronavigation in pituitary surgery   总被引:2,自引:0,他引:2  
Hardy J 《Surgical neurology》1999,52(6):648-649
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PURPOSE: To evaluate interobserver test-retest reliability of the Teller Acuity Card procedure for assessment of grating acuity at ages 1, 2, 3.5, 4.5, and 5.5 years, for HOTV letter acuity at 3.5 and 4.5 years, and for Early-Treatment Diabetic Retinopathy Study (ETDRS) letter acuity at 5.5 years in the multicenter study of Cryotherapy for Retinopathy of Prematurity (CRYO-ROP). METHODS: Subjects were the 73 participants in the CRYO-ROP study who had acuity assessed at one or more ages by two of the seven study visual acuity testers as part of a quality control procedure. All subjects had birth weights of less than 1251 g, and all had severe (threshold) ROP in one or both eyes. RESULTS: For sighted eyes, interobserver agreement for grating acuity (across all five test ages) was 0.5 octave or better in 57% of eyes and 1.0 octave or better in 85% of eyes. Interobserver agreement for letter acuity (3.5-, 4.5-, and 5.5-year test ages) was 0.5 octave or better in 71% of eyes and 1.0 octave or better in 93% of eyes. For all eyes (sighted and blind), Kendall rank correlation coefficients (Tau) were 0.86, 0.83, and 0.94 for grating, HOTV, and ETDRS acuity, respectively. Kappa statistics on data from all eyes indicated excellent interobserver agreement for grating, HOTV, and ETDRS acuity (0.73, 0.80, and 0.84, respectively). Interobserver agreement was not related to age or to severity of retinal residua of ROP. CONCLUSIONS: Excellent interobserver agreement for grating acuity measurements and for letter acuity measurements was obtained. Results suggest that with careful training and implementation of quality control procedures, high reliability of visual acuity results is possible in clinical populations of young children.  相似文献   
64.
Three methods approved by the National Committee for Clinical Laboratory Standards for testing the susceptibility of anaerobic bacteria were used to evaluate the fluoroquinolone, trovafloxacin. The methods gave essentially comparable results with 126 anaerobes and with three quality control strains. A collaborative study defined the quality control range for trovafloxacin MICs. Trovafloxacin had good in vitro activity against the more common anaerobes (MIC 90 <- 2.0 (g/ml).Trovafloxacin (CP-99,219) is a fluoroquinolone with a broad spectrum of antibacterial activity (1–3). Its in vitro spectrum includes many anaerobic bacteria (4).The National Committee for Clinical Laboratory Standards (NCCLS) currently recommends three different methods for testing the susceptibility of anaerobic bacteria (5). The standard reference method is an agar dilution procedure using Wilkins-Chalgren agar. Two alternative methods are an agar dilution technique using Brucella blood agar and a microdilution procedure using a broth version of Wilkins-Chalgren medium. It is important to determine whether these three procedures actually produce identical test results with each antimicrobial agent likely to be tested against anaerobes.  相似文献   
65.
  • 1 It was first shown several years ago that the rostral part of the ventrolateral medulla (VLM) contains a high density of receptor binding sites for angiotensin II (AngII). In the present paper we briefly review recent studies aimed at determining the actions of both exogenous and endogenous angiotensin peptides in the rostral VLM, as well as their specific sites of action.
  • 2 The results of these studies have shown that angiotensin peptides can excite pressor and sympathoexcitatory neurons in the rostral VLM, but do not appear to affect non-cardiovascular neurons in this region.
  • 3 It is known that pressor neurons in the rostral VLM include both catecholamine and non-catecholamine neurons. There is evidence that, at least in conscious rabbits, both of these types of neurons are activated by AngII. The specific endogenous angiotensin peptide or peptides that affect pressor neurons in the rostral VLM have not yet been definitively identified.
  • 4 It is also possible that different angiotensin peptides may have different effects on pressor neurons in the rostral VLM, mediated by different receptors. Further studies will be needed to define these different functions as well as the specific receptors and cellular mechanisms that subserve them.
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Lung carcinoma is the commonest major malignancy in men in the United States and its incidence is increasing rapidly in women. It is estimated that there will have been 117,000 new cases and 101,300 deaths in 1980. The 2286 patients with lung carcinoma admitted to the Hospital of the University of Mississippi from 1955 to 1980 were reviewed by decades of chronology and of life, with respect to age, cell type, sex and racial incidence. The greatest age incidence was in the sixth and seventh decades; cell types overall were epidermoid (45% of the patients), adenocarcinoma (12% of the patients), small (oat) cell (21% of the patients), and others (22% of the patients). There was a steady increase in the incidence of disease in females, adjusted for total hospital admissions, and a less certain increase among black patients. Twenty-eight per cent of 250 patients with small cell carcinoma so studied exhibited some feature of the paraneoplastic or paraendocrine syndromes. In 41 patients with small cell carcinoma treated with multiple drug chemotherapy, there was an overall response rate of 50% and an additional "stable disease" rate of 28%. Mean survival period in this group was 52 weeks, compared with 12 weeks in patients whose diseases went untreated. Clearly, definite progress is being made, not only in our knowledge of the biology of lung carcinoma, in general, but in the treatment of small cell carcinoma in particular.  相似文献   
68.
Cataract formation following heavy ion exposure (O+8) was noted in three rhesus monkeys secondary to a study of retinal effects. The pathogenesis of these lens changes follows many, but not all, of the characteristics for "radiation cataracts." The ring-shaped opacity was not noted to occur. Posterior capsular changes were noted initially and followed through the formation of a mature cataract.  相似文献   
69.
Because of the susceptibility of some vitamins to oxidation, they are not normally added to TPN mixtures until shortly before addministration. Vitamin C (ascorbic acid) is oxidised rapidly, especially in the presence of trace elements. The aim of this study was to investigate the stability of ascorbic acid in complete TPN mixtures in Ultrastab multilayer bags, which are designed to reduce oxygen transmission and thus oxidation, in comparison with standard EVA bags. Ascorbic acid content was determined in two typical TPN mixtures providing 16 g nitrogen, 2000 kilocalories, electrolytes, trace elements and multivitamins, with and without fat emulsion, during storage at 5 degrees C for up to 3 months. In EVA bags ascorbic acid degraded by more than 75% during 24 h and was undetectable in 2-3 days. In contrast, there was a comparatively small initial loss of 15-30% ascorbic acid in mixtures stored in multilayer bags, with little further loss during 1-3 months. Bags containing fat emulsion retained higher concentrations of ascorbic acid after storage compared to those without fat emulsion, but all mixtures in multilayer bags maintained 60-80% ascorbic acid activity after 3 months. Since ascorbic acid is the most oxygen-sensitive vitamin, complete TPN mixtures with vitamins could be compounded in multilayer bags for an extended shelf life, rather than admixing just prior to administration.  相似文献   
70.
This paper develops a theoretical relation between the standardized mortality ratio (SMR) and the expected years of life and establishes a regression equation for easy conversion between these two statistics. The mathematical expression of the derived relation is an approximation, requiring an assumption of constant age-specific mortality ratios. It underestimates the "true" value calculated based on life table technique when the age-specific mortality ratios increase with age. This equation provides a conservative method to estimate the expected years of life for cohort mortality studies and facilitates an assessment of the impact of work-related factors on the length of life of the worker. It also allows one to convert the SMR to life expectancy in smaller studies whose sole objective is to determine the SMR in a working population. A 1% decrease (or increase) in the standardized mortality ratio will result in 0.1373 years increased (or decreased) life expectancy based on white male data for the US population. Furthermore, with data from 14 large oil refinery and chemical worker cohorts of white males, the "derived" expected years of life based on the regression equation closely predicts the corresponding value calculated using a standard life table technique. This statistical equation is expected to have practical applications when used in conjunction with the SMR to provide an approximate measure of life expectancy, a term and statistic familiar to most lay people.  相似文献   
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