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991.
Hepatic resection for colorectal liver metastases   总被引:1,自引:0,他引:1  
Colorectal liver metastases are a frequent and lethal complication of cancer. Hepatic resection is an effective treatment for patients with colorectal liver metastases and can provide a 25 to 35 per cent 5-year survival rate. All potential resection candidates should undergo extensive preoperative testing to exclude extrahepatic metastases and local recurrence. Contraindications to resection are the presence of (1) positive portal/celiac lymph nodes, (2) extrahepatic discontiguous disease, and (3) four or more lesions. At surgery all patients should undergo a detailed examination of the lymph nodes (periportal, retroperitoneal, regional), peritoneal surfaces, and the liver. Every resection candidate should have an intraoperative ultrasound examination of the liver. This modality will identify the presence of small, nonpalpable lesions and define the tumor-vessel relationship. Many types of resections can be performed and are classified as anatomic or nonanatomic (segmental). Preference should be given to segmental resections, because these procedures reduce blood loss, shorten operating time, and lower morbidity and mortality. Unfortunately, not all patients undergoing resection will be cured of the disease; many will develop extrahepatic disease. Effective systemic chemotherapy is necessary to improve survival in patients with colorectal cancer.  相似文献   
992.
993.
Tetrachloro(d,l-trans)1,2-diaminocyclohexane platinum (IV) (tetraplatin), a new platinum analogue, showed greater therapeutic efficacy after i.p. administration than either cis-dichlorodiammineplatinum (II) (cisplatin) or cis-diammine-1,1-cyclobutanedicarboxylate platinum (II) (carboplatin) in mice bearing i.p. implanted L1210 leukemia. At an optimal dose of 5.7 mg/kg/injection given as a single dose on days 1, 5, and 9, tetraplatin increased the median life span over controls by more than 566% with 5 of 8 long-term (50-day) survivors. In contrast, cisplatin at the same optimal dose increased survival by 186% with 2 of 8 long-term survivors, and carboplatin at an optimal dose of 75.6 mg/kg/injection increased survival by only 120% with no long-term survivors. Tetraplatin also was more effective than cisplatin when treatment was delayed until days 3, 7, and 11 after i.p. implant. A combination of tetraplatin and Adriamycin in mice bearing i.p. implanted L1210 leukemia produced more long-term survivors over a wider range of doses than could be achieved with either drug alone. Tetraplatin at 5.7 mg/kg/injection and Adriamycin at 3 mg/kg/injection on days 1, 5, and 9 increased survival by more than 566% with 8 of 8 50-day survivors. Using the same treatment schedule, combinations of tetraplatin with either cisplatin, carboplatin, daunomycin, or 5-fluorouracil did not produce therapeutic efficacy greater than that seen with tetraplatin alone. The in vitro cellular uptake of platinum by L1210 cells at 37 degrees C was about 4-fold higher after exposure to tetraplatin compared to cisplatin following a 2-h incubation at the two concentrations examined (2.5 and 5 micrograms/ml). Comparative pharmacological studies were performed in rats at a single dose of 3 mg/kg i.v. The t1/2 beta for total platinum in plasma was 29.10 h (7.47 h for unbound platinum) after the administration of tetraplatin and 23.70 h (13.09 h for unbound platinum) after cisplatin. By 48 h the urinary excretion of platinum after tetraplatin and cisplatin was 30.1% and 41.4%, respectively. Tissue distribution of platinum was similar after either complex. Thus, tetraplatin has similar pharmacological properties to cisplatin and like cisplatin is a candidate for combination chemotherapy. However, tetraplatin may be superior to cisplatin in some therapeutic situations based on its greater efficacy against selected tumors.  相似文献   
994.
Value of pneumoperitoneum in the diagnosis of visceral perforation   总被引:4,自引:0,他引:4  
The presence or absence of pneumoperitoneum may not be as reliable an indicator of visceral perforation as commonly thought. Visceral perforation as commonly thought. Visceral perforation resulted in pneumoperitoneum in only 51 percent of patients in this study. Pneumoperitoneum occurred in 14 percent of patients in whom the extraalimentary intraperitoneal air had sources other than a perforated viscus. These patients' clinical findings were often indistinguishable from those of patients with a perforated viscus, and three patients underwent celiotomy unnecessarily. The routine use of the left lateral decubitus film to detect pneumoperitoneum and the judicious use of gastrointestinal contrast studies should be part of the optimal management of patients with suspected visceral perforation.  相似文献   
995.
To assess myocardial glucose metabolism and perfusion in 142 myocardial segments with defects seen at thallium-201 single photon emission computed tomography (SPECT), 27 studies with positron emission tomography (PET) utilizing nitrogen-13 ammonia and fluorine-18 deoxyglucose were performed in 26 patients. Myocardial infarction was defined on the basis of concordant reductions in segmental perfusion and glucose utilization; myocardial ischemia, on the basis of preservation of glucose utilization (metabolic viability) in segments with hypoperfusion at rest. Of the 142 segments analyzed, 101 had fixed defects, 31 had partially reversible defects, and ten had completely reversible defects. Preserved glucose utilization was identified in 47 (46.5%) of the segments with fixed defects and 20 (64.5%) of the segments with partially reversible defects. Of the ten segments with completely reversible defects, five (50%) were normal, and five (50%) exhibited ischemia at PET. Visual improvement in a persistent thallium defect at delayed imaging was not associated with residual glucose metabolic activity. Thus, PET can be used to detect glucose metabolic activity in a significant proportion of myocardial segments with fixed or partially redistributing defects seen at thallium SPECT, which suggests that the extent of tissue viability in patients with ischemic heart disease is underestimated at thallium scintigraphy.  相似文献   
996.
997.

Purpose

Hypopituitary patients have a reduced life expectancy owing to cardiovascular events. We investigated the prevalence of metabolic syndrome in hypopituitary patients for a follow-up period of at least 1 year in comparison with an age- and sex-matched nationwide control group.

Methods

A total of 515 patients with hypopituitarism who visited Seoul National University Hospital between January 2000 and December 2010 were included. Data for an age- and sex-matched control group were obtained from the Korean National Health and Nutrition Examination Surveys (KNHANES) (n = 1545). Metabolic syndrome was defined according to the modified National Cholesterol Education Program (NCEP-ATPIII).

Results

The prevalence of metabolic syndrome did not differ significantly between the hypopituitary and control groups for men (34.9 versus 30.3 %), but the risk of metabolic syndrome was higher in hypopituitary women than in controls (39.8 versus 28.5 %). In both sexes, the risks of central obesity and dyslipidemia were higher in the hypopituitary group than in the control group. Men had lower risks of hypertension and hyperglycemia in the hypopituitary group, which attenuated the risk of metabolic syndrome. Age greater than 40 years and obesity (BMI ≥25 kg/m2) contributed to a higher risk of metabolic syndrome.

Conclusions

The metabolic syndrome prevalence was higher in the hypopituitry group than in the control group in Korean women, and this was attributed to an increased risk of central obesity and dyslipidemia. Accordingly, early intervention to reduce metabolic syndrome needed in hypopituitary patients, i.e. women.
  相似文献   
998.
999.
1000.

Purpose

To compare information from self-report and electronic medical records for four common comorbidities (diabetes, hypertension, myocardial infarction, and other heart diseases).

Methods

We pooled data from two multiethnic studies (one case–control and one survivor cohort) enrolling 1,936 women diagnosed with breast cancer, who were members of Kaiser Permanente Northern California.

Results

Concordance varied by comorbidity; kappa values ranged from 0.50 for other heart diseases to 0.87 for diabetes. Sensitivities for comorbidities from self-report versus medical record were similar for racial/ethnic minorities and non-Hispanic Whites, and did not vary by age, neighborhood socioeconomic status, or education. Women with a longer history of comorbidity or who took medications for the comorbidity were more likely to report the condition. Hazard ratios for all-cause mortality were not consistently affected by source of comorbidity information; the hazard ratio was lower for diabetes, but higher for the other comorbidities when medical record versus self-report was used. Model fit was better when the medical record versus self-reported data were used.

Conclusions

Comorbidities are increasingly recognized to influence the survival of patients with breast or other cancers. Potential effects of misclassification of comorbidity status should be considered in the interpretation of research results.
  相似文献   
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