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41.
Suresh K. Mukherji Julian G. Rosenman Mitchell Soltys Aziz Boxwala Mauricio Castillo Vincent Carrasco Stephen M. Pizer 《Skull base》1996,6(3):141-146
This paper presents our initial experience utilizing a new technique which allows CT and MR image fusion in patients with skull base lesions. Eleven patients with a variety of skull base lesions underwent CT and MR imaging prior to surgery. Both sets of images were coregistered using customized software. The CT and MR data sets were then combined and viewed in a single interactive image formar using a high-speed graphic computing system. Image fusion allowed simultaneous visualization of the bony skull base anatomy (CT) and detailed soft tissue anatomy (MR) using a single image format. Combining both modalities was felt to provide a better assessment of the extent of lesions and improve understanding of their relationship to adjacent bony and neurovascular anatomy. Specifically, image fusion enhanced awareness of location of skill base lesions with respect to the cavernous sinuses. Gasserian ganglia, carotid arteries, and jugular foramina. For tumors arising within the internal auditory canal (IAC), fused images allowed better delineation of the lateral aspect of the lesion with respect to the fundus of the IAC. Thus, fusion of CT and MR studies provides a unique image format which has advantages over single modality display. We believe image fusion is beneficial for surgical planning and for treatment planning of complex skull base malignancies treated with radiotherapy. 相似文献
42.
P A Patriarca R J Biellik G Sanden D G Burstyn P D Mitchell P R Silverman J P Davis C R Manclark 《American journal of public health》1988,78(7):833-836
We evaluated the diagnostic performance of 15 clinical case definitions for pertussis in 233 patients who developed acute respiratory illness during community outbreaks in Wisconsin and Delaware. Using results from culture (Regan-Lowe media) and serology (Ig-class-specific ELISA) as diagnostic standards, cough for greater than or equal to 14 days was both sensitive (84 per cent-92 per cent) and specific (63 percent-90 per cent) in identifying patients with pertussis. This definition may be useful in monitoring pertussis outbreaks and for investigating contacts of culture-positive cases. 相似文献
43.
S O Schweitzer B Mitchell J Landsverk L Laparan 《Public health reports (Washington, D.C. : 1974)》1993,108(1):37-44
The recent literature on economic issues of hospice care leaves several questions unanswered. The most important issue concerns how this type of care can be made financially attractive to patients and families for whom it is a medical option. A major study of a home-based pediatric hospice program permitted a more careful analysis than was previously feasible of the charges for hospice care and how those charges are paid. Data on provider utilization and duration in the program were obtained retrospectively on 177 patients. Costs of incidental expenditures and indirect costs were obtained prospectively from the families of 27 patients. A cost model was developed which is general enough to be used by other hospitals that might contemplate establishing a similar hospice program. Our findings are that insurance coverage, especially for publicly funded patients, is likely to be a major impediment for families deciding whether or not to use a hospice program at home. 相似文献
44.
David C. Mitchell Martin R. Prince Joan K. Frisoli Roy E. Smith Richard F. M. Wood 《Lasers in surgery and medicine》1993,13(2):149-157
The yellow color of atherosclerotic plaque is due to the presence of carotenoids, which absorb light between 430–530 nm and account for the preferential ablation of plaque by the pulsed dye laser operating at 480 nm. This study was designed to examine tissue uptake of β-carotene and the effect of uptake on arterial plaque ablation. Forty-two atherosclerotic NZW rabbits were given intravenous β-carotene at a dose of 40 mg/kg, twice weekly and killed between 1 hour and 28 days after the initial injection. β-carotene was not detected in control specimens but was significantly greater in plaque than in normal wall at all time points following β-carotene injection (P < 0.04 Mann Whitney U test). The ablation threshold was significantly lower in β-carotene treated plaque than in untreated plaque or normal arterial wall (P < 0.01, Fisher's exact test). In this model β-carotene is preferentially taken up into arterial plaque, resulting in increased absorption of laser radiation at 480 nm and enhanced tissue ablation. © 1993 Wiley-Liss, Inc. 相似文献
45.
Jeffrey A. Gray Stephen N. Mitchell Michael H. Joseph Grigory A. Grigoryan Sharon Dawe Helen Hodges 《Drug development research》1994,31(1):3-17
Data are reviewed, largely from experiments in the authors'laboratory, that suggest three modes of action of systemic nicotine in producing three different types of effect upon behavior and cognitive function. (1) Preexposure of a stimulus without consequence makes it harder subsequently to form associations to that stimulus, a form of selective attention known as latent inhibition. Latent inhibition is blocked by nicotine, an effect that is apparently mediated by a nicotine-induced increase in dopamine release in the nucleus accumbens. (2) A single dose of nicotine proactively increases the partial reinforcement extinction effect measured several weeks later: that is, resistance to extinction is decreased by nicotine in animals that have been trained on a continuous reinforcement schedule, and increased in animals trained on a partial reinforcement schedule. This effect appears to be due to increased synthesis of tyrosine hydroxylase in the cell bodies of noradrenergic neurons in the locus coeruleus, followed by axonal transport to the hippocampus and increased synthesis and release of noradrenaline in that structure. (3) Nicotine improves vigilance in animals with cognitive deficits due to destruction of the forebrain cholinergic projection system, either as a consequence of excitotoxic lesions of the nuclei of origin of this system or after prolonged alcohol consumption; and also in human subjects with Alzheimer's disease (in which this system undergoes degeneration). This effect is most likely due to an action at denervated cholinergic synapses in the hippocampus and neocortex. © 1994 Wiley-Liss, Inc. 相似文献
46.
The records of obese and nonobese victims of blunt trauma were compared to determine if obese individuals are predisposed to a specific injury pattern. Prospectively collected data on 6368 adults admitted to a level I trauma center over a 4-year period were analyzed. Twelve percent (743 patients) met Body Mass Index (weight/height2) criteria for obesity (greater than or equal to 30 kg/m2). The obese group was older (p less than 0.01) and had lower ISSs (p less than 0.05) and higher GCS scores (p less than 0.01). More obese patients were injured in vehicular crashes (62.7% vs. 54.1% [p less than 0.01]). The obese victims were more likely to have rib fractures, pulmonary contusions, pelvic fractures, and extremity fractures and less likely to have incurred head trauma and liver injuries (p less than 0.05). Obese people injured in vehicular crashes had a similar injury pattern with no difference in seating position, direction of impact, seat belt use, and ejection. 相似文献
47.
Differential cytokeratin expression in normal, hyperplastic and malignant epithelial cells from human prostate. 总被引:5,自引:0,他引:5
E R Sherwood L A Berg N J Mitchell J E McNeal J M Kozlowski C Lee 《The Journal of urology》1990,143(1):167-171
Studies were undertaken to define the expression of cytokeratins in normal, hyperplastic and malignant epithelial cells from human prostate. Cytokeratin (CK) polypeptides, separated by two-dimensional electrophoresis, were identified by immunoblotting with CK-specific monoclonal antibodies. CK polypeptides 5, 7, 8, 15, 18 and 19 were identified in fresh normal and hyperplastic prostate. Expression of CK 15 has not been previously reported in human prostate. Analysis of central and peripheral zone tissues from human prostate did not reveal qualitative differences in CK expression between these areas. Epithelial cells harvested from fresh BPH tissue by percoll gradient centrifugation and propagated in vitro using selective culture techniques showed alterations in CK expression compared to intact human prostate. Specifically, CKs 6, 14, 16 and 17 were noted in cultured BPH epithelial cells but not fresh normal prostate or BPH tissue. Immunoblot analysis of the established prostate cancer cell lines PC3, DU145 and LNCAP showed expression of CKs 8 and 18 but not CKs 5, 7 and 15 which were observed in benign prostate. These studies further characterize CK expression in benign and malignant human prostate and provide insights which may be useful in differentiating normal, hyperplastic and malignant epithelial cells in the human prostate gland. 相似文献
48.
The association of non-insulin-dependent diabetes mellitus with perceived quality of life in a biethnic population: the San Luis Valley Diabetes Study. 下载免费PDF全文
E M Caldwell J Baxter C M Mitchell S M Shetterly R F Hamman 《American journal of public health》1998,88(8):1225-1229
OBJECTIVES: This study evaluated the association between quality of life and non-insulin-dependent diabetes mellitus (NIDDM) status, and whether this association differs between Hispanics and non-Hispanic Whites. METHODS: Between 1986 and 1989, cross-sectional data on perceived quality of life (PQOL) were collected from 223 persons with NIDDM and 753 non-diabetic subjects. RESULTS: After adjustment, persons with NIDDM rated their PQOL significantly lower than did control subjects. The relationship of diabetes and PQOL did not differ by ethnicity. The number of complications of diabetes was not associated with lower PQOL scores. CONCLUSIONS: Control and treatment strategies should reflect an understanding of the impact that diabetes has on social functioning, leisure activities, and physical and mental health. 相似文献
49.
William B. Mitchell Patricia Marten Dibartolo Timothy A. Brown David H. Barlow 《Archives of sexual behavior》1998,27(2):197-207
Effects of positive and negative musical mood induction on subjective and objective sexual arousal were examined in a group of sexually functional males (N = 24). Subjects evidenced significantly greater objective and subjective sexual response in the positive mood induction condition relative to both baseline and a neutral control condition. In contrast, the negative mood induction condition yielded significantly less objective sexual arousal than baseline and a neutral control condition. Data provide additional empirical support for the hypothesized impact of mood on sexual arousal. 相似文献
50.