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41.
Diet and chronic atrophic gastritis: a case-control study   总被引:2,自引:0,他引:2  
A hospital-based case-control study of gastric cancer precursor lesions was conducted in a high-risk black population in southern Louisiana. Ninety-three subjects with biopsy-proved advanced chronic atrophic gastritis were compared to two control series: a gastroscopy clinic series and a general hospital-admission series. Dietary case-control differences indicated a protective effect associated with fruit and vegetable intake and with dietary vitamin C and a risk elevation associated with milk consumption. The protective effect associated with consumption of fruits, vegetables, and vitamin C is consistent with findings for gastric cancer and with the etiologic hypothesis of intragastric nitrosation. A twofold increased risk was associated with cigarette smoking. Gastric juice pH, NO3-, and NO2- were determined for subjects undergoing gastroscopy, and comparisons were made between this high-risk U.S. group and a Colombian population with a much greater magnitude of risk; the latter had higher NO3- and NO2- levels. An increase in pH was associated with increasing severity of gastric lesions. Levels of pH and NO2- concentration were significantly correlated (P less than .0005); however, in Louisiana the large difference in NO2- concentration associated with pH elevation is not associated with histopathologic severity. Divergent trends with severity of lesions for NO3- concentration were seen in the two populations.  相似文献   
42.
Visual-field areas to a I2e stimulus were measured planimetrically using an X-Y digitizer and a computer program. Sampling of normal subjects and patients suspected of having glaucoma was done at two points in time. Calculations of eye-wall stress were done using ultrasonic data and intra-ocular pressure (IOP) measurements from patient records. For those suspected of having glaucoma who developed chronic open-angle glaucoma (COAG), the time of transition was the second point in time. The visual field area was regressed against patient age at the two points in time. No difference in the regression slopes was found for the normal subjects and unchanged patients. The patients who did develop glaucoma were significantly different. The mean annual rate of visual-field change (rate of decay) was calculated and found to be 28.5 mm2/year for the normals, 153.5 mm2/year for the suspects, and 376.4 mm2/year for those patients who developed glaucoma. The rate of visual-field decay only correlated with patient age (P = 0.03) and eye-wall stress (P < 0.01) in the patients who developed glaucoma.  相似文献   
43.
Depression is under-detected, but is treatable and relapses can be prevented. Living with depression, whether acute or chronic, has consequences for quality of life, premature end of life, and productive life. Thoughtful and strategic quality improvement (QI) programs offer one avenue for improving the treatment of depression. Part I of this two-part series addresses improving the treatment of depression and employing disease management as a strategy to accomplish that aim. This article, part II, provides an overview of other QI initiatives that demonstrated treatment effectiveness for depression, including several used in managed care practice.Currently, the majority of QI programs for depression target adult patients; therefore, there are future challenges ahead as managed care attempts to address the needs of special populations, such as adolescents and older adults. Public education, professional education, and population-based interventions are also considerations as part of successful treatment. Although consumer-based interventions are typically more expensive, they may ultimately yield the best results for improving depression care for the consumer and payors based on available research. The success of a consumer-centric approach is highly reliant on the person’s engagement with QI programs, the treating clinician’s appreciation and support of such depression programs, and managed care’s response to solving quality problems using continuous monitoring, evaluation, feedback, system enhancements, and training. Models of collaboration between consumers and medical and behavioral health systems offer the most promising approaches to care improvements for patients with depression.  相似文献   
44.
Postoperative Cognitive Dysfunction in Middle-aged Patients   总被引:13,自引:0,他引:13  
Background: Postoperative cognitive dysfunction (POCD) after noncardiac surgery is strongly associated with increasing age in elderly patients; middle-aged patients (aged 40-60 yr) may be expected to have a lower incidence, although subjective complaints are frequent.

Methods: The authors compared the changes in neuropsychological test results at 1 week and 3 months in patients aged 40-60 yr, using a battery of neuropsychological tests, with those of age-matched control subjects using Z-score analysis. They assessed risk factors and associations of POCD with measures of subjective cognitive function, depression, and activities of daily living.

Results: At 7 days, cognitive dysfunction as defined was present in 19.2% (confidence interval [CI], 15.7-23.1) of the patients and in 4.0% (CI, 1.6-8.0) of control subjects (P < 0.001). After 3 months, the incidence was 6.2% (CI, 4.1-8.9) in patients and 4.1% (CI, 1.7-8.4) in control subjects (not significant). POCD at 7 days was associated with supplementary epidural analgesia and reported avoidance of alcohol consumption. At 3 months, 29% of patients had subjective symptoms of POCD, and this finding was associated with depression. Early POCD was associated with reports of lower activity scores at 3 months.  相似文献   

45.
Summary PANC02 is a ductal adenocarcinoma of the pancreas that is resistant to every known class of clinically active antitumor agent. To study the mechanism(s) underlying the intrinsic drug resistance of this tumor, a mammary adenocarcinoma (CA-755) that also grows in C57/BL mice and is known to be drugsensitive was used for comparison. PANC02 resistance and CA-755 sensitivity to several antitumor agents and to X-ray therapy was confirmed in mice, and PANC02 also demonstrated relative resistance in tissue culture. Relative to Chinese hamster ovary (CHO) and CA-755 cells, PANC02 did not appear to show a higher rate of mutation to drug resistance in culture as based on the 6-thioguanine resistance marker. Although P-glycoprotein characteristic of the multidrug resistance (MDR) phenomenon could be demonstrated at the mRNA level using a sensitive RNAse protection assay, the level of expression found was several orders of magnitude lower than that observed in phenotypic MDR cell lines. Furthermore, quinidine failed to increase the sensitivity of PANC02 cells to Adriamycin under conditions that clearly potentiated the toxicity of the drug to a CHO cell line exhibiting classic MDR traits. The heterogeneity in the distribution of drugs was inferred as being significantly greater in PANC02 versus CA-755 cells in vivo as based on measurements of within-animal, within-tumor variance in the distribution of the marker compounds inulin and antipyrine. Although it may not be the only mechanism involved, this greater intratumor heterogeneity in drug distribution could theoretically play a major role in the intrinsic drug resistance of PANC02 in vivo.Supported by grant CH-458 from the American Cancer Society, by grant CA-28034 from the National Cancer Institute, and in part by Cancer Center Core Support grant, NIH-NCI-CA-16672. Animals were maintained in facilities approved by the American Association for Accreditation of Laboratory Animal Care and in accordance with current United States Department of Agriculture, Department of Health and Human Services, and National Institutes of Health regulations and standards  相似文献   
46.
47.
Early gastric cancer. 21-year experience.   总被引:7,自引:1,他引:6       下载免费PDF全文
W L Bringaze  rd  C W Chappuis  P Correa    I Cohn  Jr 《Annals of surgery》1986,204(2):103-107
From 1963 through 1983, 327 patients underwent resection for gastric adenocarcinoma at Charity Hospital in New Orleans. Fifteen lesions (4.6%) were early gastric carcinoma (limited to the mucosa or submucosa regardless of nodal metastases). These lesions were in eight men and seven women (14 blacks and 1 white), with a mean age of 65.3 years (range: 52-80 years). Upper gastrointestinal series were obtained in 13 (6 suspicious, 2 inconclusive, and 5 normal). By comparison, endoscopy on 11 patients provided a tissue diagnosis in ten patients (90.9%). Surgical procedures ranged from total gastrectomy to a local excision, and every specimen was free of lymph node metastases. Macroscopically, there were six Type I, four Type IIb, and Type IIc, three Type III, and one with two separate lesions (IIa and IIb); microscopically, ten were intramucosal and five had submucosal invasion. Five-year survival calculated by the actuarial method was 64.2% (observed) and 100% (adjusted). This compares with 18.8% (observed) for all 327 patients. Six of the patients with early gastric cancer are alive (range: 16-219 months). The nine patients who died had no evidence of recurrent disease at the time of death. Surgical resection of early gastric carcinoma in the United States offers an excellent prognosis similar to the Japanese experience. Increased detection of gastric carcinoma in its curable stages may be achieved through early endoscopic investigation of symptomatic patients.  相似文献   
48.
The purpose of this study was to analyze the clinical aspects in 130 patients presenting periodic lateralized epileptiform discharges (PLEDs) in their EEG and to compare these results with those found in the literature. Etiology, neurologic deficit, seizure occurrence, and evolution were studied in each patient by historical review. The recordings were obtained on 8- or 16-channel EEGs with electrode placement according to the International 10-20 System. Recordings containing PLEDs were selected. PLEDs were defined as repetitive periodic, focal, or hemispheric epileptiform discharges (spikes, spike and waves, polyspikes, sharp waves) usually recurring every 1 to 2 seconds. The statistical study was carried out via the chi(2) test using the computer program SPSS. The main etiology found in this group of patients was stroke (61 of 130 patients). Other processes found were brain infections, tumors, hematomas, and several other entities grouped together as miscellaneous (anoxic encephalopathy, subarachnoid hemorrhage, craniocerebral trauma, Creutzfeldt-Jacob disease, migraine, multiple sclerosis, and aminophylline intoxication). Half of these patients (65 of 130) developed seizures, mostly partial motor seizures. No significant relation between etiology and seizures was found (chi(2) = 2.81, P = 0.4222). Seizures recurred in 14 of 130 patients during a follow-up of 14.5 months. PLEDs were not recorded in any EEG at the time of seizure recurrence. PLEDs constitute a distinctive but uncommon EEG phenomenon of repetitive, periodic, and stereotyped lateralized complexes. In agreement with the literature, PLEDs were associated with an acute process and occurred early during the course of the illness in all patients studied and were usually associated with structural lesions, with stroke being the main etiology. Traditionally, seizures occur with PLEDs but it is also accepted that they can exist in patients who never develop epileptic activity, either clinically or electrically, as demonstrated in 50% of the patients studied. No significant association between seizures and any etiology could be found. It was not demonstrated that the occurrence of seizures may influence the outcome in any way.  相似文献   
49.
The pulmonary effects of closure of a patent ductus arteriosus (PDA) were investigated in 11 premature infants with severe respiratory distress syndrome. Successful closure of a PDA did not improve the short-term severity of pulmonary disease (24 and 48 h after treatment) as judged by the arterial/alveolar oxygen tension ratio or the amount of ventilatory support. Also, pulmonary mechanics measured 24 h before, 24 and 48 h after treatment, were not statistically different.Conclusion Infants with severe respiratory disease requiring high ventilation pressure and high oxygen concentration, where structural changes in the lungs are already established, will rarely show short-term improvement in pulmonary disease as a result of closure of a PDA. The overall clinical condition may, however, improve as a result of reduced cardiovascular strain. Earlier treatment of a PDA could reduce the ventilation period and the possible risk of developing chronic lung disease.  相似文献   
50.
CHIP (325 mg/M2), a second generation cisplatin derivative, was administered intravenously every 3 weeks to 85 pediatric patients with recurrent sarcomas (19), osteosarcomas (20), neuroblastoma (23), germ cell tumors (10), and other malignant tumors (7). Thirty-eight of them had been previously exposed to cisplatin. Partial remissions were only observed in 3 of 23 (13% SE=7%) patients having neuroblastoma. Severe thrombocytopenia (65%) and neutropenia (35%) were the dose limiting factors.  相似文献   
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