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91.
Between 1982 and 1992, 24 women with Stage III clear cell ovarian cancer were identified from the tumor registry. Thirty-four women with Stage III papillary serous tumors treated between 1987 and 1989 were used as a comparison. All patients underwent cytoreductive surgery followed by conventional platinum-based chemotherapy. In the women with clear cell histology, nine (37.5%) had endometriosis in the surgical specimen compared with one (3%) in the papillary serous group (P= 0.002). Ten women (42%) with clear cell histology experienced a thromboembolic event during the course of treatment, compared to six (18%) in the papillary serous group (P= 0.05). In the group with clear cell histology, overall, 70% of women had progressive disease. Fifty-two percent experienced clinical progression while receiving platinum-based chemotherapy. In addition, four patients were found to have progressive disease at second-look laparotomy. Only two patients had a pathologic complete response. In the group with papillary serous histology, 29% overall had progressive disease while on chemotherapy (P= 0.005). The median survival for the women with clear cell histology was 12 months compared to 22 months for those with papillary serous (P= 0.02). For women with clear cell histology, univariate analysis was used to evaluate prognostic factors. Age less than 50 was a poor prognostic factor (P= 0.045). The presence of endometriosis, thromboembolic event, or optimal cytoreduction were not prognostic factors (P= 0.67,P= 0.34,P= 0.39). Patients with advanced clear cell ovarian cancer have a poor response to conventional platinum-based chemotherapy and overall prognosis is poor.  相似文献   
92.
Validating three-dimensional imaging of the breast   总被引:3,自引:0,他引:3  
Losken A  Seify H  Denson DD  Paredes AA  Carlson GW 《Annals of plastic surgery》2005,54(5):471-6; discussion 477-8
The potential to extrapolate accurate data from 3-dimensional (3D) images of the breast is enormous and will greatly improve our ability to qualitatively determine differences in shape, size, and contour. The validity of these calculated measurements is important and needs to be determined before any meaningful data can be evaluated. PART I: Premastectomy 3D images (3dMD patient) were obtained on 19 breasts (14 patients). The volume of the mastectomy specimen was determined intraoperatively using water displacement. Two independent raters then calculated breast volumes using the 3D images and software, and these were compared with the intraoperative volume. Inter- and intrarater reliability was determined. Part II: Surface measurements (nipple to notch) were then evaluated on 20 breasts (10 patients) by comparing the 3D image determined distance to the known measurements. PART I: The average breast volume was 500 mL, compared with 489 mL for rater 1 and 490 mL for rater 2. The relative difference between the measured volume and the calculated volume for rater 1 and rater 2 was about -2%, with a standard deviation of +/- 13% to 16%. The coefficient of reproducibility for each reader was excellent, at 0.80 for rater 1 and 0.92 for rater 2. The level of agreement between the readers was also high at 0.975. Part II: The average nipple to notch measurement for each patient was 27.1 cm, compared the calculated average of 25.1 cm for rater 1 and 26.1 cm for rater 2. The mean relative difference between the measured and calculated distances for raters 1 and 2 was about -6%, with a standard deviation of +/- 6% to 7%. The level of agreement between readers was high, at 0.975. The ability to objectively determine breast volume and surface measurements using 3D imaging technology is now available with consistent and reproducible accuracy. Measurements are typically underestimated, with more variability when calculating volumes. Although inherent subjectivity will always exist when evaluating breast measurements, 3D technology provides invaluable information, particularly in the longitudinal evaluation of results.  相似文献   
93.
Neurocutaneous melanosis (NCM) is a rare phakomatosis characterized by a focal or diffuse proliferation of melanin-producing cells in both the skin and the leptomeninges. This syndrome is believed to result from an error in the morphogenesis of embryonal neuroectoderm. Two-thirds of patients with NCM have giant congenital melanocytic nevi, and the remaining one-third have numerous lesions but no giant lesions. Patients may present with neurologic manifestations early in life secondary to intracranial hemorrhages, impairment of cerebrospinal fluid circulation, or malignant transformation of the melanocytes. The prognosis of patients with symptomatic NCM is poor.  相似文献   
94.
95.
Oxidative stress decreases immune defences and is also suggested to participate in the activation of HIV virus replication. That is why we decided to explore some biomarkers of oxidative stress (reduced glutathione, lipoperoxides, true malondialdehyde and vitamin C) in 20 HIV positive patients whose HIV replication was determined by measurement of RNA viral load. Reduced glutathione is decreased in HIV positive patients, without correlation with the viral load. The patients mean content of lipoperoxides is twice that of controls but with such a large range that there is no statistical difference.  相似文献   
96.
Serum Leptin Elevation in Obese Women with PCOS: A Continuing Controversy   总被引:9,自引:0,他引:9  
PURPOSE: To evaluate leptin levels in a sample of obese women with PCOS and compare the results with obese and non-obese control, to be ultimately correlated with BMI, and insulin sensitivity. METHODS: Leptin and insulin assays by immuno-radiometric method, glucose assay by enzymatic colorimetric method. RESULTS: Leptin levels were significantly different between obese and non-obese subjects, and were significantly different between insulin resistant and non-insulin resistant obese PCOS, but were not significantly different between obese non-insulin resistant PCOS, and obese controls. CONCLUSIONS: Body mass index and insulin resistance are the two main factors governing serum leptin levels.  相似文献   
97.
98.
Limb salvage after infrainguinal bypass graft failure   总被引:2,自引:0,他引:2  
OBJECTIVE: The purpose of this study was to examine the outcome of patients in whom an infrainguinal bypass graft failed. METHODS: This was a retrospective analysis of consecutive patients undergoing infrainguinal bypass grafting in a single institution over 8 years. RESULTS: Six hundred thirty-one infrainguinal bypass grafts were placed in 578 limbs in 503 patients during the study period. The indication for surgery was limb-threatening ischemia in 533 patients (85%); nonautologous conduits were used in 259 patients (41%), and 144 (23%) were repeat operations. After a mean follow-up of 28 +/- 1 months (median, 23 months; range, 0-99 months), 167 grafts (26%) had failed secondarily. The rate of limb salvage in patients with graft failure was poor, only 50% +/- 5% at 2 years after failure. The 2-year limb salvage rate depended on the initial indication for bypass grafting: 100% in patients with claudication (n = 16), 55% +/- 8% in patients with rest pain (n = 49), and 34% +/- 6% in patients with tissue loss (n = 73; P <.001). The prospect for limb salvage also depended on the duration that the graft remained patent. Early graft failure (<30 days; n = 25) carried a poor prognosis, with 2-year limb salvage of only 25% +/- 10%; limb salvage was 53% +/- 5% after intermediate graft failure (<2 years, n = 110) and 79% +/- 10% after late failure (>2 years, n = 15; P =.04). Multivariate analysis revealed shorter patency interval before failure (P =.006), use of warfarin sodium (Coumadin) postoperatively (P =.006), and infrapopliteal distal anastomosis (P =.01) as significant predictors for ultimate limb loss. CONCLUSION: The overall prognosis for limb salvage in patients with failed infrainguinal bypass grafts is poor, particularly in patients with grafts placed because of tissue loss and those with early graft failure.  相似文献   
99.
Summary: Na‐montmorillonite (MMT) with a cation exchange capacity (CEC) of 90 meq/100 g was converted to MMT‐CTAB and MMT‐CPC by the intercalation of cetyltrimethylammonium bromide (CTAB) and cetylpyridinium chloride (CPC), respectively. The intercalation of CPC onto the basal space of the montmorillonite expanded the basal space from 12.19 to 21.47 Å, whereas in the case of CTAB, the spacing was only expanded to 19.35 Å. The MMT‐CPC and MMT‐CTAB forms were subsequently used as hosts for the preparation of polystyrene nanocomposites via intercalative free‐radical polymerization of styrene. Different structures were obtained by varying the preparation conditions; the exfoliated and intercalated nanocomposites were characterized by X‐ray diffraction (XRD), transmission electron microscopy (TEM), thermal gravimetric analysis (TGA), and differential scanning calorimeter (DSC). The produced nanocomposites exhibited improved thermal stability in comparison with that of pure polystyrene above 400 °C especially in the case of the nanocomposites based on the MMT‐CPC, in which intercalation exists. A glass transition temperature (Tg) could not be detected for the prepared nanocomposites using DSC; this was assumed to result from the restricted molecular motion of the polymer chains.

XRD pattern of PS nanocomposites prepared by intercalative polymerization.  相似文献   

100.
The incidence of perinatal death resulting from rhesus Rh isoimmunization has dropped dramatically since the introduction of Rh immunoglobulin. However, Rh sensitization continues to be one of the leading causes of fetal anemia. Our patient is a 38-year-old woman; she gives a history of 2 uneventful pregnancies followed by 5 consecutive stillbirths. Investigations revealed an anti-D titre of 1/2048 and anti-C titre of 1/256. Ultrasound examination revealed fetal ascites at 18 weeks gestation. The fetus had a total of 9 successful intrauterine transfusions. She was delivered by an elective cesarean section at 34 weeks gestation; outcome was a healthy female baby weighing 2060 g. Examination at 9 month of age showed normal growth and neurodevelopment.  相似文献   
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