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161.
PURPOSE: Chromogenic in situ hybridization (CISH) is a new modification of the fluorescence in situ hybridization (FISH) technique for detection of oncogene amplification in archival tumor samples. In CISH, the oncogene probe is detected using a peroxidase reaction, allowing use of transmitted light microscopy. We compared detection of HER-2/neu amplification by CISH with a Food and Drug Administration-approved two-color FISH test in an interlaboratory setting. EXPERIMENTAL DESIGN: Formalin-fixed paraffin-embedded tumor samples from 197 breast cancers were analyzed for HER-2 amplification by CISH. Two-color FISH (PathVysion) CISH of 17 centromere was done if the observer considered it necessary to ascertain amplification status in tumors with borderline HER-2 CISH copy numbers. RESULTS: Paired CISH/FISH results were available from 192 (97%) of 197 cases, no clear difference in success rates of either method was observed. Centromere 17 CISH was considered necessary in seven tumors. CISH and two-color FISH results were concordant in 180 cases (93.8%). There were 92 and 88 tumors found HER-2 amplified and nonamplified, respectively, by both methods. Eight tumors were amplified by CISH but not by FISH, and four tumors exhibited the opposite condition (kappa coefficient 0.875). In 7 of 12 cases differences between the two methods could have related to a lack of CISH chromosome 17 information. The remaining cases were explained by difficult histology (ductal carcinoma in situ, poor representativity, dense lymphocytic infiltration, or intratumoral heterogeneity). CONCLUSIONS: These results indicate that CISH could provide an accurate and practical alternative to FISH for clinical diagnosis of HER-2/neu oncogene amplification in archival formalin-fixed breast cancer samples.  相似文献   
162.
Successful reconstruction of the anterior cruciate ligament (ACL) depends on anatomic placement of a graft ligament substitute. This study examined the accuracy of a plain radiograph in determining femoral tunnel position during ACL reconstruction. Nine cadaveric distal femurs had six separate tunnels made in each specimen: 12:00 (high position), 1:30 (anatomic position), and 3:00 (low position) in the left femora and 12:00 (high), 10:30 (anatomic), and 9:00 (low) in the right femora. At each position on the clock face, two 9-mm tunnels were drilled, leaving 2 mm (correct) and 12 mm (incorrect) of posterior wall intact. With a radiopaque tunnel dilator in each tunnel, a true lateral radiograph, a 10 degree externally rotated lateral radiograph, and a 10 degree internally rotated lateral radiograph were obtained. All radiographs were analyzed for femoral tunnel placement in the anteroposterior plane with the four-quadrant method described by Harner et al and the ratio method described by Aglietti et al. Statistically significant differences could only be distinguished between anatomic (10:30), anterior (12-mm rim), and posterior (2-mm rim) positions. There were no statistically significant differences for any of the other positions when comparing true laterals to true laterals, true laterals to internal or external oblique views, or when comparing internal and external oblique views. A malpositioned anterior tunnel (12-mm rim posterior), which was "low" at 9:00 or "high" at 12:00 in the notch (malplaced), could not be distinguished reliably from an anatomically correct placed tunnel with a single-plane lateral radiograph.  相似文献   
163.
PURPOSE: Vaccines, cytokines, and other biologic-based therapies are being developed as antineoplastic agents. Many of these agents are designed to induce an autologous immune response directed against the malignancy. In contrast, hematopoietic stem-cell transplantation is being developed as a form of allogeneic immunotherapy. This study tests the tolerance and antineoplastic activity of sequential infusions of partially HLA-matched allogeneic blood mononuclear cells (obtained from relatives) when administered outside of the context of a hematopoietic stem-cell transplantation. The cells are irradiated to prevent graft-versus-host disease. PATIENTS AND METHODS: Fifteen patients with relapsed or refractory malignancies for which no standard therapy was available were enrolled onto a clinical trial designed to assess the tolerability and antineoplastic effects of irradiated partially HLA-matched blood mononuclear cells obtained from relatives. RESULTS: There was disease regression in three patients with metastatic renal cell carcinoma during treatment. There was disease progression in six patients with metastatic renal cell carcinoma and two patients with metastatic melanoma during treatment. There was no change in disease state in several other patients. CONCLUSION: Irradiated allogeneic blood mononuclear cells administered outside the context of hematopoietic stem-cell transplantation may induce disease responses in patients with relapsed or refractory malignancies. Transfusion of irradiated allogeneic blood mononuclear cells should be developed further as a novel therapeutic antineoplastic approach.  相似文献   
164.
In three infants with excessive crying, two girls aged 3 and 13 months and a boy aged 5 weeks, feeding with a hypoallergenic formula was started because cow's milk protein intolerance was suspected. Yet in two of the cases, another explanation for the excessive crying, notably parental distress, was more likely based on the history. In these 2 cases, no provocation test with cow's milk had been performed, and the hypoallergenic formula had been continued for a prolonged period of time (without introduction of solid foods), even though the excessive crying had not ceased. Prolonged feeding with the hypoallergenic formula when cow's milk protein intolerance is not confirmed by appropriate provocation testing, may strengthen the parents' misconception that their baby has severe food intolerance, causing unnecessary delay in the introduction of solid foods. This may hamper the normal development of taste and oral motor development.  相似文献   
165.
Dudley RA  Johansen KL  Brand R  Rennie DJ  Milstein A 《JAMA》2000,283(9):1159-1166
Context  Evidence exists that high-volume hospitals (HVHs) have lower mortality rates than low-volume hospitals (LVHs) for certain conditions. However, few employers, health plans, or government programs have attempted to increase the number of patients referred to HVHs. Objectives  To determine the difference in hospital mortality between HVHs and LVHs for conditions for which good quality data exist and to estimate how many deaths potentially would be avoided in California by referral to HVHs. Design, Setting, and Patients  Literature in MEDLINE, Current Contents, and FirstSearch Social Abstracts databases from January 1, 1983, to December 31, 1998, was searched using the key words hospital, outcome, mortality, volume, risk, and quality. The highest-quality study assessing the mortality-volume relationship for each given condition was identified and used to calculate odds ratios (ORs) for in-hospital mortality for LVHs vs HVHs. These ORs were then applied to the 1997 California database of hospital discharges maintained by the California Office of Statewide Health Planning and Development to estimate potentially avoidable deaths. Main Outcome Measures  Deaths that potentially could be avoided if patients with conditions for which a mortality-volume relationship had been treated at an HVH vs LVH. Results  The articles identified in the literature search were grouped by condition, and predetermined criteria were applied to choose the best article for each condition. Mortality was significantly lower at HVHs for elective abdominal aortic aneurysm repair, carotid endarterectomy, lower extremity arterial bypass surgery, coronary artery bypass surgery, coronary angioplasty, heart transplantation, pediatric cardiac surgery, pancreatic cancer surgery, esophageal cancer surgery, cerebral aneurysm surgery, and treatment of human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS). A total of 58,306 of 121,609 patients with these conditions were admitted to LVHs in California in 1997. After applying the calculated ORs to these patient populations, we estimated that 602 deaths (95% confidence interval, 304-830) at LVHs could be attributed to their low volume. Additional analyses were performed to take into account emergent admissions and distance traveled, but the impact of loss of continuity of care for some patients and reduction in the availability of specialists for patients remaining at LVHs could not be assessed. Conclusions  Initiatives to facilitate referral of patients to HVHs have the potential to reduce overall hospital mortality in California for the conditions identified. Additional study is needed to determine the extent to which selective referral is feasible and to examine the potential consequences of such initiatives.   相似文献   
166.
A 2-min focal application of Polyethylene Glycol (PEG) to injured mammalian spinal cords can offer significant yet limited restoration of functional and structural integrity. However, longer application of PEG has not been tested in similar injuries. In this study, isolated spinal cord white matter strips from adult guinea pigs were subjected to a 25 min exposure of PEG (MW: 2000; 50% w/w), with or without prior compression. When applied in a continuous steam, PEG, with a delay of about 6 min, suppressed the compound action potential (CAP) amplitude to 64+/-4% of the pre-PEG level in uninjured cords and to 64+/-7% in compressed cord strips. Both recovered to 70+/-5% (uninjured) and 88+/-11% (compressed) of the pre-PEG level following wash. When PEG was applied in a pulsatile manner, no significant decrease of CAP amplitude was observed. In summary, our results show that focal continuous application of PEG has minimal toxicity if applied for less than 5 min. Pulsatile application could extend this duration to at least 25 min with no toxicity. This study could be useful in determining the optimal protocol for the use of PEG in both animal research and human spinal cord victims.  相似文献   
167.
Brand MI  Saclarides TJ  Dobson HD  Millikan KW 《The American surgeon》2000,66(4):412-5; discussion 415-6
The purpose of this study was to determine the morbidity and mortality in elderly patients undergoing liver resections for metastatic colon cancer and compare them with those of a control group of younger patients. The charts of all patients undergoing liver resection for colon cancer were retrospectively reviewed. Patients less than 70 years of age (Group A) were compared with patients 70 years of age or older (Group B). Between 1971 and 1995, 167 liver resections were performed for metastatic colorectal cancer. Of these, 41 patients were in Group A and 126 patients were in Group B. The mean age of Group A was 74.5 years, and that of Group B was 57 years. American Society of Anesthesiologists (ASA) classification was similar for both groups (Groups A and B were 75.6% and 81.1% ASA class II, respectively). Anatomic resections were performed in 49 per cent and wedge resections in 51 per cent of patients in Group A, and 68 and 32 per cent in Group B, respectively. Estimated blood loss was slightly less for Group A (1575 vs 1973 cm3), as was operative time (4.0 vs 4.7 hours). In-hospital mortality rate was 7.3 per cent for Group A and 2.4 per cent for Group B. The major morbidity rates were 29 and 17.5 per cent, respectively. Intensive care unit care was necessary in 73 per cent (mean length of stay 3.9 days) for Group A and 62.6 per cent (mean length of stay 2.0 days) for Group B. The average length of hospitalization was 13.1 days for Group A and 16.6 days for Group B. The recurrence rates were similar for the two groups [56% (Group A) vs 66% (Group B)], but mean survival was longer for younger patients (22.9 vs 33.5 months). We conclude that liver resection for colorectal cancer liver metastases in properly selected patients older than 70 years of age can be performed with acceptable morbidity and mortality rates. The long-term survival for older patients is less than that for younger patients, but is still a significant length of time. Therefore, we conclude that age alone is not a contraindication to liver resection for colorectal cancer metastases in patients older than 70.  相似文献   
168.
The National Notifiable Disease Surveillance System (NNDSS) received 982 tuberculosis (TB) notifications in 2003, of which 947 were new cases, 33 were relapses and two were cases with unknown history. The incidence of TB in Australia has remained at a stable rate since 1985 and was 4.9 cases per 100,000 population in 2003. The high-incidence groups remain people born overseas and Indigenous Australians at 19.9 and 8.7 cases per 100,000 population, respectively. By contrast the incidence in non-Indigenous Australians was 0.9 per 100,000. Comparison of the 2003 TB notification data against the performance indicators set by National Tuberculosis Advisory Committee highlights that enhanced TB control measures should be considered among these high-risk groups.  相似文献   
169.
BACKGROUND: The current tumor-node-metastasis system is inadequate to accurately classify patients in terms of prognosis. Thus, with the availability of recently developed molecular tools, considerable interest lies in discovering prognostic markers in order to guide treatment decisions. In this study, we sought to determine the prognostic significance of the cell cycle regulator cyclin D1 in oropharyngeal squamous cell carcinoma (OSCC). EXPERIMENTAL DESIGN: We studied the protein expression levels of cyclin D1 on a tissue microarray composed of 63 OSCCs with long-term follow-up data available. Protein expression was analyzed with an automated in situ quantitative (AQUA) method which allows preservation of tissue morphology while quantifying protein expression in paraffin-embedded tissue. RESULTS: The mean follow-up time was 35 months. High cyclin D1 nuclear expression was associated with increased 5-year local recurrence rate (48% versus 15%), inferior 5-year disease-free survival (16% versus 58%), and inferior 5-year overall survival (17% versus 53%). In multivariate Cox regression, high nuclear cyclin D1 expression was an independent predictor for local recurrence, disease-free survival, and overall survival at 5 years. CONCLUSIONS: Our results indicate that quantitative assessment of nuclear cyclin D1 expression level by automated in situ quantitative analysis is a strong predictor for outcome in OSCC. Thus, cyclin D1 may be a potential target for molecular intervention in patients with oropharyngeal squamous cell cancer.  相似文献   
170.
PURPOSE: Temozolomide, a DNA methylating agent used to treat melanoma, induces DNA damage, which is repaired by O6-alkylguanine alkyltransferase (ATase) and poly(ADP-ribose) polymerase-1 (PARP-1)-dependent base excision repair. The current study was done to define the effect of temozolomide on DNA integrity and relevant repair enzymes as a prelude to a phase I trial of the combination of temozolomide with a PARP inhibitor. EXPERIMENTAL DESIGN: Temozolomide (200 mg/m2 oral administration) was given to 12 patients with metastatic malignant melanoma. Peripheral blood lymphocytes (PBL) were analyzed for PARP activity, DNA single-strand breakage, ATase levels, and DNA methylation. PARP activity was also measured in tumor biopsies from 9 of 12 patients and in PBLs from healthy volunteers. RESULTS: Temozolomide pharmacokinetics were consistent with previous reports. Temozolomide therapy caused a substantial and sustained elevation of N7-methylguanine levels, a modest and sustained reduction in ATase activity, and a modest and transient increase in DNA strand breaks and PARP activity in PBLs. PARP-1 activity in tumor homogenates was variable (828 +/- 599 pmol PAR monomer/mg protein) and was not consistently affected by temozolomide treatment. CONCLUSIONS: The effect of temozolomide reported here are consistent with those documented in previous studies with temozolomide and similar drug, dacarbazine, demonstrating that a representative patient population was investigated. Furthermore, PARP activity was not inhibited by temozolomide treatment and this newly validated pharmacodynamic assay is therefore suitable for use in a proof-of-principle phase I trial a PARP-1 inhibitor in combination with temozolomide.  相似文献   
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