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91.
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Seizures and civilian head injuries   总被引:4,自引:3,他引:1  
Although several studies have reported on the risk of "early seizures" (seizures occurring within 7 days following a head injury), the reported proportions of patients experiencing these seizures vary from 1.4 to 15%. This wide divergence may be due to problems with methodology such as case selection and definitions of head injury and early seizures. In a series of 702 patients admitted with a head injury to Cook County Hospital (CCH), Chicago, Illinois, 29 (4.1%) had early seizures. This proportion is twice as high as one previously reported in a comparable series. This may reflect an actual difference between the two series or a case selection bias serving to elevate the proportion of patients with early seizures at CCH.  相似文献   
94.
Identification and histologic study of the sentinel node (SN) is an acceptable, yet not firmly established, guide for treating intermediate-thickness melanoma. This study widens the range of applications of this technique. We included 97 patients with intermediate-thickness melanoma lesions or lesions for which there is no standard treatment. Fifty-six underwent preoperative lymphoscintigraphy, and all underwent intraoperative lymphatic mapping (IOLM) using blue dye, followed by frozen section study and total node processing by serial sections. Elective lymph node dissection was performed in cases of metastasis to the sentinel node or technical failures with high risk. Four categories were defined: (A) intermediate-thickness lesions (mean 2.27 mm) (n= 45); (B) thin lesions (mean 1.14 mm) with risk factors of regional failure (n= 27); (C) lesion thickness close to but more than 4 mm (n= 10); and (D) lesions of undetermined thickness (n= 15). Median follow-up was 30 months (range 13–51 months). Intraoperative lymphatic mapping successfully identified the sentinel node (SN) in 93% of basins explored. Metastases were detected in 11 SNs. There were three lymph basin recurrences in patients with previously negative SNs, all salvaged by therapeutic lymph basin dissection and are NED (no evidence of disease). Two SN+ patients had systemic recurrences; one died of his disease, and the other is alive with disease. One SN patient died NED owing to other cause. This technique spared 83% of category A patients from lymph node dissection. It allowed better staging and better decision making for treatment in categories B and D; and it prevented early regional recurrences in category C patients. Intraoperative lymphatic mapping with SN guidance is a novel, low-morbidity approach applicable and advantageous for a wide range and subgroups of melanoma patients.  相似文献   
95.
OBJECTIVES: We evaluated prostate volume and prostate-specific antigen (PSA) as predictors of acute urinary retention (AUR) in men with benign prostatic enlargement (BPE). METHODS: Data were pooled from 3 identical 2-year, multinational, multicenter, non-US, placebo-controlled finasteride trials in 4,222 men with BPE and no evidence of prostate cancer. RESULTS: The 2-year incidence of spontaneous AUR was higher in placebo patients with enlarged prostates (4.2% in men with prostate volume > or =40 ml vs. 1.6% in the <40 ml group) and higher PSA levels (3.9% in men with PSA > or =1.4 ng/ml vs. 0.5% in the <1.4 ng/ml group) at baseline. Finasteride reduced AUR incidence by 61% in men with larger prostates, by 63% in men with higher PSA levels, and by 47% in men with smaller prostates, compared with placebo. CONCLUSIONS: BPE patients with larger prostate volumes, higher PSA levels and no evidence of prostate cancer have an increased risk of developing AUR and therefore derive the greatest benefit from the risk reduction seen with finasteride therapy.  相似文献   
96.
PURPOSE: We conducted a pilot study assessing the effects of the selective estrogen receptor modulator, tamoxifen, on the pharmacokinetics, pharmacodynamics, and safety of the steroidal, irreversible aromatase inhibitor (AI), exemestane, when the two were coadministered in postmenopausal women with metastatic breast cancer. EXPERIMENTAL DESIGN: Patients with documented or unknown hormone receptor sensitivity were eligible. Patients received oral exemestane at 25-mg once daily. Starting day 15, oral tamoxifen at 20-mg once daily, was added. We measured plasma concentrations of exemestane, estrone, estrone sulfate, and estradiol after 14 days of exemestane monotherapy and after approximately 4 weeks of combination therapy. The incidence and severity of adverse events were assessed by physical examination and patient reporting. RESULTS: We treated 18 patients. All had received prior chemotherapy and/or hormonal therapy, eight and six, respectively, with single-agent selective estrogen receptor modulators or irreversible aromatase inhibitors; no hormonal therapy was given within 30 days of study entry. Plasma exemestane concentrations and estrone, estrone sulfate, and estradiol suppression were unchanged after approximately 4 weeks of tamoxifen coadministration. All drug-related adverse events were grades 1 or 2; none was unexpected. Although not a formal study end point, antitumor activity was noted, with two partial responses and four cases of stable disease among 17 evaluable patients after a 9-month median follow-up (range, 2.5-19 months). CONCLUSIONS: This pilot study provides evidence that coadministration of tamoxifen does not affect exemestane pharmacokinetics or pharmacodynamics and that the combination is well-tolerated and active. Further clinical investigation is warranted.  相似文献   
97.
PURPOSE: To allow the longitudinal investigation of molecular events associated with the progression of human hepatocellular carcinoma (HCC), we sought to develop a murine model by orthotopic implantation of tumor fragments obtained from patients diagnosed at early stage. EXPERIMENTAL DESIGN: Tumor pieces (2 x 2 mm) were implanted on the liver surface of nu/nu mice. After xenograft growing, subsequent passages were performed to achieve long-term implant viability. Isolation of tumoral hepatocytes was done to establish new cell lines. HCC characteristics, proliferation rate, apoptotic index (terminal deoxynucleotidyl transferase-mediated nick end labeling), and expression of cell-cycle regulators (cyclins E and A, p21(Cip1), p27(Kip1), p16(INK4a), pRb, and p53) were assessed by Western Blot and immunohistochemistry, to correlate them with tumor progression. RESULTS: Five (50%) of the 10 primary HCCs resulted in small slow-growing liver implants. Three of them are viable after 48 months, whereas the remaining two survived for 15 and 13 months. Xenografts throughout passages exhibited a more aggressive phenotype with a poorer degree of differentiation, intense proliferation, moderate apoptosis, cell-cycle deregulation, p53 alterations, microvascular invasion, and dissemination. In one single passage, we observed critical growth delay, which was associated with significant p27(kip1) overexpression. We established the anchor-free growing BCLC-9 cell line from one xenograft. This has gains of chromosomes 7, 5p, 6q, and 9q, is hepatitis B virus-DNA positive, does not secrete alpha-fetoprotein, and has TP53 missense mutations in codons 192 and 242. CONCLUSIONS: The orthotopic implantation of early HCC fragments in nude mice provides a useful model to investigate the mechanisms of human HCC evolution and to establish new cell lines.  相似文献   
98.
The objective of this study was to examine the effects of the intakeof dietary fat upon colorectal cancer risk in a combined analysis of datafrom 13 case-control studies previously conducted in populations withdiffering colorectal cancer rates and dietary practices. Original datarecords for 5,287 cases of colorectal cancer and 10,470 controls werecombined. Logistic regression analysis was used to estimate odds ratios (OR)for intakes of total energy, total fat and its components, and cholesterol.Positive associations with energy intake were observed for 11 of the 13studies. However, there was little, if any, evidence of anyenergy-independent effect of either total fat with ORs of 1.00, 0.95, 1.01,1.02, and 0.92 for quintiles of residuals of total fat intake (P trend =0.67) or for saturated fat with ORs of 1.00, 1.08, 1.06, 1.21, and 1.06 (Ptrend = 0.39). The analysis suggests that, among these case-control studies,there is no energy-independent association between dietary fat intake andrisk of colorectal cancer. It also suggests that simple substitution of fatby other sources of calories is unlikely to reduce meaningfully the risk ofcolorectal cancer.  相似文献   
99.
100.
Predicting abdominal adipose tissue in overweight Latino youth.   总被引:1,自引:0,他引:1  
OBJECTIVES: 1) Examine associations between visceral adipose tissue (VAT), subcutaneous abdominal adipose tissue (SAAT), and anthropometric and demographic variables; 2) generate and cross-validate prediction equations for estimating VAT and SAAT in overweight Latino children. STUDY DESIGN: Cross-sectional. PARTICIPANTS: 196 overweight 8-13-year-old Latino youth. Two-thirds (n = 131) were randomly assigned to a development group to generate prediction equations for VAT and SAAT; one-third (n = 65) was used as a cross-validation group. METHODS AND PROCEDURES: Anthropometric measurements (height, weight, skinfold thicknesses, and circumferences) were performed. VAT and SAAT were measured using magnetic resonance imaging (MRI). RESULTS: The strongest univariate correlate for VAT was waist circumference (WC) (r = 0.65, p < 0.01) while the strongest correlate for SAAT was hip circumference (r = 0.88, p < 0.001). Regression analyses showed approximately 50% of the variance in VAT was explained by WC (43.8%), Tanner stage (4.2%) and calf skinfold (1.7%). Variance in the SAAT model was explained by WC (77.8%), triceps skinfold (4.2%) and gender (2.3%). Residual analyses showed no bias in either equation. Though mean differences between measured and predicted VAT and SAAT were small, there was a large degree of variability at the individual level especially for VAT. CONCLUSIONS: Both VAT and SAAT prediction equations performed well at the group level, but the relatively high degree of variability suggests limited clinical utility of the VAT equation. MRI is currently required to derive an accurate measure of VAT at the individual level.  相似文献   
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