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81.
Successful closure of traumatic macular holes.   总被引:4,自引:0,他引:4  
PURPOSE: To establish the efficacy of vitreoretinal surgery without the use of transforming growth factor-beta or autologous platelet concentrate in the repair of traumatic macular holes. METHODS: This retrospective review consisted of 16 eyes from 16 consecutive patients treated by five vitreoretinal surgeons at a single institution between 1993 and 1997. Intervention included pars plana vitrectomy with creation of posterior vitreous detachment, placement of 14% to 16% C3F8 gas, and postoperative face-down positioning. Ten eyes received intraoperative autologous plasmin to facilitate formation of posterior vitreous detachment. Main outcome measures were anatomic closure rate and visual outcome. RESULTS: Anatomic closure of the macular holes was achieved in 15 (94%) of 16 eyes, with an average follow-up of 7 months. Six (38%) eyes achieved visual acuity of 20/40 or better. Visual acuity improved by 2 or more lines in 11 (69%) of 16 eyes. The average preoperative logMAR-converted visual acuity of 20/175 improved to 20/60 postoperatively. CONCLUSION: Traumatic macular holes can be closed successfully with substantial visual recovery without the use of transforming growth factor-beta or platelet concentrate.  相似文献   
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83.
Acute catatonic syndromes occurring in the context of various medical and neuropsychiatric conditions, including schizophrenia, have been shown to respond well to benzodiazepines (BZD). However, there have been no studies specifically designed to address the BZD treatment response of persistent catatonic states. Eighteen patients with clinically stable chronic schizophrenia, who also displayed enduring catatonic features, underwent a 12-week long, random assignment, double-blind, placebo-controlled cross-over trial with lorazepam (6 mg/day). A comprehensive assessment, including the subjects’ clinical and motor (catatonic as well as drug-induced movement disorders) condition, was performed at baseline and four weekly intervals thereafter. Pre-existing medication was kept constant throughout the study. Lorazepam had no effect on the subjects’catatonic signs and symptoms, suggesting that acute and chronic catatonic syndromes associated with schizophrenic illness might have a different neurobiological basis. Received: 25 May 1998/Final version: 22 September 1998  相似文献   
84.
When it came time to reduce the 1991 federal budget, it was not surprising that the budget cutters set their sights on Medicare to reduce the deficit. But why does Medicare appear to be such a major target at budget time, and when are "cuts" really cuts?  相似文献   
85.
A combination of celecoxib and selenium was used in a randomized double-blind Phase II trial as a preliminary study to a multicenter Phase III colorectal cancer chemoprevention trial using these two agents together. The purpose of this trial was to determine whether high-selenium baker's yeast [(Saccharomyces cerevisiae) 200 microg once daily] in combination with celecoxib (400 mg once daily) altered the steady-state plasma concentration of celecoxib or produced clinically significant toxicities. Seventy-three healthy subjects (ages 40-75 years) were recruited to the 6-week study from the general local population and were randomized to either the celecoxib plus selenized baker's yeast group or the celecoxib plus placebo group after a 2-week run in period of celecoxib only. Blood samples were taken at baseline (to document that there was no evidence of celecoxib intake), after the 2-week run-in period on celecoxib to verify steady-state blood levels of this agent, and at end of study (4 weeks postrandomization). Toxicities were monitored at 2 weeks after initiation of celecoxib, at 4 weeks after initiation, and at the end of the study. Blood level concentrations of celecoxib did not differ between the two groups as determined by high-performance liquid chromatography analysis nor were there significant differences in blood chemistry values between the two groups. Subjects' self-report of general physical toxicities was uncommon and limited to National Cancer Institute toxicity grade 2 or less; however, 2 female participants (3%) were removed from the study medications because of grade 2 edema and significant weight gain after 2 and 2.5 weeks of celecoxib administration. In conclusion, high-selenium yeast and celecoxib can be taken at the described doses with minimum short-term negative effects. In future Phase III chemoprevention trials of celecoxib, weight gain should be carefully monitored, and participants should be made aware of this potential side effect before study entry.  相似文献   
86.
PURPOSE: Radiation oncologists and hospice professionals both provide end-of-life care for oncology patients, and little has been written about the interface between these two groups of specialists. Hospice professionals were surveyed to assess the perceived need for palliative radiotherapy in the hospice setting, to investigate factors that limit the access of hospice patients to radiotherapy, and to suggest areas of future collaboration on education, research, and patient advocacy. PATIENTS AND METHODS: Members of the National Hospice and Palliative Care Organization (NHPCO) and American Society for Therapeutic Radiology and Oncology jointly authored a questionnaire to investigate the beliefs of hospice professionals toward the use of radiotherapy for oncology patients in hospice. The questionnaire was distributed to all NHPCO member institutions, and the results were compiled and statistically analyzed. RESULTS: Four hundred eighty of more than 1,800 surveyed facilities responded to the questionnaire. The findings suggest that the majority of hospice professionals feel that radiotherapy is important in palliative oncology and that radiotherapy is widely available in the United States. Yet less than 3% on average of hospice patients served by hospices responding to the survey actually received radiotherapy in 2002. The most common barriers to radiotherapy in hospice care include radiotherapy expense, transportation difficulties, short life expectancy, and educational deficiencies between the specialties. CONCLUSION: Multiple barriers act to limit the use of palliative radiotherapy in hospice care. Finding ways to surmount these obstacles will provide opportunity for improvement in the end-of-life care of cancer patients.  相似文献   
87.
This study was undertaken to determine whether selected risk factors for esophageal and gastric cancer are associated with tumors that overexpress cyclin D1. Archived tumor tissue was available for 630 esophageal and gastric cancer patients who participated in a population-based case-control study. Patients were categorized into case groups based on whether protein overexpression of the cyclin D1 gene, as assessed by immunohistochemistry, was present (cyclin D1+, n = 285) or not (cyclin D1-, n = 345) in the tumor. The distribution of risk factors in each of these case groups was then compared with the distribution among the 695 controls. Multivariate-adjusted odds ratios (OR) for esophageal adenocarcinoma were reduced in relation to use of aspirin and other nonsteroidal anti-inflammatory drug (NSAID) use but only among patients with cyclin D1+ tumors (0.45, 95% confidence interval [CI] = 0.26, 0.79) and not among those with cyclin D1- tumors (1.12, 95% CI = 0.67, 1.86). A similar pattern was observed for gastric cardia adenocarcinomas. In contrast, ORs for esophageal squamous cell carcinoma and noncardia gastric adenocarcinomas in relation to NSAID use were reduced, regardless of cyclin D1 status. ORs did not vary with cyclin D1 status in relation to alcohol, body size, or cigarette smoking, with the following exception; for noncardia gastric adenocarcinomas the cyclin D1- tumors showed a 2-fold elevation in the OR with ever smoking. These data suggest that the reduction in risk associated with NSAID use may be restricted to those esophageal and gastric cardia adenocarcinomas that overexpress cyclin D1.  相似文献   
88.
PURPOSE: To evaluate changes in epidermal growth factor receptor (EGFR) phosphorylation and its downstream signaling in tumor and surrogate tissue biopsies in patients with metastatic breast cancer treated with erlotinib, an EGFR tyrosine kinase inhibitor, and to assess relationships between biomarkers in tumor and normal tissues and between biomarkers and pharmacokinetics. PATIENTS AND METHODS: Eighteen patients were treated orally with 150 mg/d of erlotinib. Ki67, EGFR, phosphorylated EGFR (pEGFR), phosphorylated mitogen-activated protein kinase (pMAPK), and phosphorylated AKT (pAKT) in 15 paired tumor, skin, and buccal mucosa biopsies (at baseline and after 1 month of therapy) were examined by immunohistochemistry and analyzed quantitatively. Pharmacokinetic sampling was also obtained. RESULTS: The stratum corneum layer and Ki67 in keratinocytes of the epidermis in 15 paired skin biopsies significantly decreased after treatment (P = .0005 and P = .0003, respectively). No significant change in Ki67 was detected in 15 tumors, and no responses were observed. One was EGFR-positive and displayed heterogeneous expression of the receptor, and 14 were EGFR-negative. In the EGFR-positive tumor, pEGFR, pMAPK, and pAKT were reduced after treatment. Paradoxically, pEGFR was increased in EGFR-negative tumors post-treatment (P = .001). Although markers were reduced in surrogate and tumor tissues in the patient with EGFR-positive tumor, no apparent associations were observed in patients with EGFR-negative tumor. CONCLUSION: Erlotinib has inhibitory biologic effects on normal surrogate tissues and on an EGFR-positive tumor. The lack of reduced tumor proliferation may be attributed to the heterogeneous expression of receptor in the EGFR-positive patient and absence of target in this cohort of heavily pretreated patients.  相似文献   
89.
PURPOSE: Hepatocellular carcinoma (HCC) is generally considered as a sex hormone-dependent tumor, and hormonal therapy has been proposed as a strategy for the treatment of HCC. The aim of the study is to investigate the effect of megestrol acetate, a synthetic progesteronal agent, on growth of HepG2 cells in vitro and in vivo. EXPERIMENTAL DESIGN: Cell growth in vitro was assessed by a colormetric method, and cell growth in vivo was assessed by tumor volumetrics. RESULTS: Megestrol acetate was shown to inhibit the growth of HepG2 cells in vitro in dose- and time-dependent manners with an IC (50) of 260 microm (24-h incubation). The growth of HepG2 cell-transplanted tumors in nude mice was also inhibited by i.p. injection of megestrol acetate (10 mg/kg/day). The tumor volumes of the megestrol acetate-treated group regressed to 59% of controls by week 6 and to 41% of controls by week 13. Apoptosis following G(1) arrest was observed in megestrol acetate-treated cells and may be a mechanism through which megestrol acetate inhibits HepG2 cells. Megestrol acetate was also demonstrated to have a beneficial effect on the weight gain of tumor-bearing nude mice, and the mean weight of the megestrol acetate-treated animals was higher than that of controls from week 4 of the treatment period, and the differences were statistically significant in week 5 and 6 (P < 0.05, compared with controls). No significant survival advantage was, however, demonstrated in the treatment group. CONCLUSIONS: This study showed that megestrol acetate inhibited the growth of HepG2 cells grown in vitro and in vivo. These data provide useful information for clinical study of megestrol acetate for the treatment of HCC.  相似文献   
90.
Twenty-five patients with osteolytic metastases had computed tomography (CT) scans before and 3 months after palliative radiotherapy. The median % density change following single 8 Gy, 20 Gy/5#, 30 Gy/10# were: 128 (range 98–255), 141 (79–342), and 145 (65–235), respectively. It is feasible to evaluate remineralization of osteolytic lesions with palliative radiotherapy.  相似文献   
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