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61.
Volumetric rendering is a new approach to three-dimensional (3D) imaging that overcomes many of the drawbacks of currently available surface-rendering systems. Its application on the Pixar Imaging System in two cases of acetabular fracture was assessed to illustrate the features of the technique. The fast-computing architecture and large memory of this system allow rapid generation of a series of high-quality 3D images in each plane of rotation (x or spinal axis, z or somersaulting axis) that can be viewed as independent static images or as an animated real-time video loop. Editing to remove the normal contralateral hemipelvis enhances appreciation of acetabular abnormalities. Every pixel of computed tomographic data is preserved, allowing representation of both soft tissue and bone as translucent overlap. The presentation of data also allows detection of subtle abnormalities and features and minimizes the artifact generation common in surface-rendered images.  相似文献   
62.
A randomized clinical trial was conducted in women with bulky (suboptimal) Stage III and Stage IV ovarian carcinoma, using doxorubicin (Adriamycin) and cyclophosphamide with or without cisplatin. There were 440 evaluable cases, of which 227 had measurable disease. One hundred twenty of these latter patients were treated with cyclophosphamide and doxorubicin (CA), while 107 received cyclophosphamide, doxorubicin and cisplatin (CAP). The clinical complete response (CR) rate for CA was 26% (31/120) compared with 51% (55/107) for CAP (P = less than 0.0001). Of 23 CRs receiving CA who had a second-look laparotomy, only four were negative; of 39 CRs receiving CAP and a second-look, 13 were negative (not statistically significant). The response duration for patients with measurable disease (median 14.6 versus 8.8 months), progression-free interval for all patients (13.1 versus 7.7 months), and survival for patients with measurable disease (19.7 versus 15.7 months) showed a statistically significant advantage for CAP; however, there was no difference in survival of patients with nonmeasurable disease. Toxicity was more severe with CAP but was tolerable. Thus, the addition of cisplatin improves the chemotherapy of advanced ovarian carcinoma.  相似文献   
63.
A retrospective review of four Gynecologic Oncology Group protocols involving aggressive chemotherapy was carried out to assess the following. Whether granulocyte determinations, which require a differential count resulting in extra cost and time, added pertinent clinical information to that obtained from the white blood cell count alone. If, there is a predictable relationship between the white blood cell count and the platelet count as a reflection of bone marrow toxicity, and whether one can predict when maximum myelosuppression will occur during a treatment program. This data revealed that the white blood count and granulocyte levels are closely related; that rarely is life-threatening thrombocytopenia noted in the absence of leukopenia; and that myelosuppression can occur during any course of treatment and is not predictable. Thus, for these treatment regimens in gynecologic malignancies, the white blood count is sufficient for monitoring toxicity and adjusting future courses of chemotherapy. Only when the white blood count is severely depressed is it necessary to monitor the granulocyte and platelet counts.  相似文献   
64.
During the years 1976 to 1987, 82 patients with Ménière's disease received a tympanoclysis with gentamicin on a daily basis. Dosage was titrated up to the initial symptoms of vestibular or cochlear intoxication. Sixty-four patients filed for a complete follow-up examination; it was possible to interview 15, while three patients were lost. Vertigo was eliminated in 70 (89%) cases. Nine patients (11%) remained disabled, while demonstrating typical paroxysmal positional vertigo in three cases. Speech discrimination improved in 13%, stabilized in 54%, and deteriorated in 33%. Hearing improved significantly better if, preoperatively, there had been low frequency loss rather than a flat audiogram. HALLPIKE's caloric test demonstrated residual vestibular activity in 72 percent. In the author's opinion, tympanoclysis with gentamicin offers a technically simple, riskless, and effective method to rehabilitate patients with disabling Ménière's disease.  相似文献   
65.
Plasma growth hormone (GH) and prolactin concentrations were measured by radioimmunoassay in unanesthetized male rats after stereotaxic microinjection of adrenergic agents and 6-hydroxydopamine into the preoptic-anterior hypothalamic area (PO/AHA). Norepinephrine, epinephrine, isoprenaline and clonidine failed to stimulate GH, moreover, 16 nanomoles norepinephrine produced a decrease. However, these agents stimulated prolactin secretion and the mixed alpha antagonist phentolamine, administered systemically, inhibited the stimulatory action of epinephrine on prolactin secretion. GH and prolactin secretory patterns were not affected by 6-hydroxydopamine disruption of catecholamine terminals in the PO/AHA. GH responses to adrenergic agonists and the failure of 6-hydroxydopamine to affect GH secretory patterns indicate that PO/AHA norepinephrine afferents do not facilitate GH secretion. Taken in conjunction with previous studies, the results suggest that there must be an extra-hypothalamic site at which norepinephrine is stimulatory for GH. Prolactin responses suggest that alpha adrenoceptors in the PO/AHA may participate in prolactin secretion.  相似文献   
66.
Summary Based upon the activity observed in this trial, there does not appear to be a significant role for AZQ as a salvage agent for leiomyosarcoma of the uterus at the dose and schedule tested. Address for offprints: GOG Headquarters, Suite 1945, 1234 Market Street, Philadelphia, PA 19107, USA  相似文献   
67.
Gastrointestinal teratomas are uncommon, benign neoplasms that occur primarily in children. A retrospective review of five cases (two gastric, one pancreatic, one mesenteric, and one in the lesser omentum) is presented with emphasis on the computed tomographic and ultrasonographic appearances. Principal findings are a well-defined mass with separate cystic and solid components of varying proportions, discrete areas with densities similar to that of fat, or coarse, globular calcifications within the solid component. Recognition of these findings may allow the radiologist to make a correct preoperative diagnosis of teratoma.  相似文献   
68.
用气相色谱研究抗氧化剂对膜脂肪酸的保护作用   总被引:3,自引:0,他引:3  
卢基贵  王伟  陈文为 《药学学报》1991,26(6):406-410
本文应用气相色谱技术直接测定三种生物膜(人红细胞膜,人血小板膜和鼠肝线粒体膜)多不饱和脂肪酸的含量变化,检测脂质过氧化程度。实验证实几种多羟酚类化合物(儿茶精,阿魏酸钠和没食子酸及其衍生物)不同程度地抑制(OH)诱导的脂质过氧化反应,并呈量效和构效关系。这类抗氧化剂对保护生物膜的结构与功能是有益的。  相似文献   
69.

Introduction

Delirium occurs in most ventilated patients and is independently associated with more deaths, longer stay, and higher cost. Guidelines recommend monitoring of delirium in all intensive care unit (ICU) patients, though few data exist in non-ventilated patients. The study objective was to determine the relationship between delirium and outcomes among non-ventilated ICU patients.

Method

A prospective cohort investigation of 261 consecutively admitted medical ICU patients not requiring invasive mechanical ventilation during hospitalization at a tertiary-care, university-based hospital between February 2002 and January 2003. ICU nursing staff assessed delirium and level of consciousness at least twice per day using the Confusion Assessment Method for the ICU (CAM-ICU) and Richmond Agitation-Sedation Scale (RASS). Cox regression with time-varying covariates was used to determine the independent relationship between delirium and clinical outcomes.

Results

Of 261 patients, 125 (48%) experienced at least one episode of delirium. Patients who experienced delirium were older (mean ± SD: 56 ± 18 versus 49 ± 17 years; p = 0.002) and more severely ill as measured by Acute Physiology and Chronic Health Evaluation II (APACHE II) scores (median 15, interquartile range (IQR) 10–21 versus 11, IQR 6–16; p < 0.001) compared to their non-delirious counterparts. Patients who experienced delirium had a 29% greater risk of remaining in the ICU on any given day (compared to patients who never developed delirium) even after adjusting for age, gender, race, Charlson co-morbidity score, APACHE II score, and coma (hazard ratio (HR) 1.29; 95% confidence interval (CI) 0.98–1.69, p = 0.07). Similarly, patients who experienced delirium had a 41% greater risk of remaining in the hospital after adjusting for the same covariates (HR 1.41; 95% CI 1.05–1.89, p = 0.023). Hospital mortality was higher among patients who developed delirium (24/125, 19%) versus patients who never developed delirium (8/135, 6%), p = 0.002; however, time to in-hospital death was not significant the adjusted (HR 1.27; 95% CI 0.55–2.98, p = 0.58).

Conclusion

Delirium occurred in nearly half of the non-ventilated ICU patients in this cohort. Even after adjustment for relevant covariates, delirium was found to be an independent predictor of longer hospital stay.  相似文献   
70.

Background Context

Predictors of outcome after surgery for degenerative cervical myelopathy (DCM) have been determined previously through hypothesis-driven multivariate statistical models that rely on a priori knowledge of potential confounders, exclude potentially important variables because of restrictions in model building, cannot include highly collinear variables in the same model, and ignore intrinsic correlations among variables.

Purpose

The present study aimed to apply a data-driven approach to identify patient phenotypes that may predict outcomes after surgery for mild DCM.

Study Design

This is a principal component analysis of data from two related prospective, multicenter cohort studies.

Patient Sample

The study included patients with mild DCM, defined by a modified Japanese Orthopaedic Association score of 15–17, undergoing surgical decompression as part of the AOSpine CSM-NA or CSM-I trials.

Outcome Measures

Patient outcomes were evaluated preoperatively at baseline and at 6 months, 1 year, and 2 years after surgery. Quality of life (QOL) was evaluated by the Neck Disability Index (NDI) and Short Form-36 version 2 (SF-36v2). These are both patient self-reported measures that evaluate health-related QOL, with NDI being specific to neck conditions and SF-36v2 being a generic instrument.

Materials and Methods

The analysis included 154 patients. A heterogeneous correlation matrix was created using a combination of Pearson, polyserial, and polychoric regressions among 67 variables, which then underwent eigen decomposition. Scores of significant principal components (PCs) (with eigenvalues>1) were included in multivariate logistic regression analyses for three dichotomous outcomes of interest: achievement of the minimum clinically important difference [MCID] in (1) NDI (≤?7.5), (2) SF-36v2 Physical Component Summary (PCS) score (≥5), and (3) SF-36v2 Mental Component Summary (MCS) score (≥5).

Results

Twenty-four significant PCs accounting for 75% of the variance in the data were identified. Two PCs were associated with achievement of the MCID in NDI. The first (PC 1) was dominated by variables related to surgical approach and number of operated levels; the second (PC 21) consisted of variables related to patient demographics, severity and etiology of DCM, comorbid status, and surgical approach. Both PC 1 and PC 21 also correlated with SF-36v2 PCS score, in addition to PC 4, which described patients' physical profile, including gender, height, and weight, as well as comorbid renal disease; PC 6, which received large loadings from variables related to cardiac disease, impaired mobility, and length of surgery and recovery; and PC 9, which harbored large contributions from features of upper limb dysfunction, cardiorespiratory disease, surgical approach, and region. In addition to PC 21, a component profiling patients' socioeconomic status and support systems and degree of physical disability (PC 24) was associated with achievement of the MCID in SF-36 MCS score.

Conclusions

Through a data-driven approach, we identified several phenotypes associated with disability and physical and mental health-related QOL. Such data reduction methods may separate patient-, disease-, and treatment-related variables more accurately into clinically meaningful phenotypes that may inform patient care and recruitment into clinical trials.  相似文献   
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