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991.
To assess the racial differences in survival of children with acute lymphocytic leukemia, we analyzed data for 1,675 white and 126 black children, diagnosed from 1955 to 1969. Blacks had a significantly shorter median survival and lower one-year and three-year survival rates than whites. There was substantial variation in racial differences by age. In addition, much of the variation between races seemed to be due to socioeconimic factors rather than strictly racial ones. Identification of the specific factors responsible for the poorer survival of children from lower social classes is sorely needed.  相似文献   
992.
Hertzberg  BS; Bowie  JD; King  LR; Webster  GD 《Radiology》1987,165(3):853-856
Sonographic evaluation of the urinary tract after bladder augmentation and replacement procedures often reveals unexpected findings that result from incorporation of bowel into the urinary bladder wall. Familiarity with such findings is important to avoid misinterpreting them as abnormalities. The authors reviewed the sonograms of 47 patients. The most common findings were thick or irregularly shaped bladder walls (96%), pseudomasses within the bladder lumen (89%), and fine debris or linear strands (47%). Pseudomasses were potentially the most confusing; they are usually attributable to normal bowel folds, intraluminal mucus collections, or segments of bowel that have been intussuscepted into the bladder to prevent reflux.  相似文献   
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Many states prohibit patients from appointing their physicians as health care proxies, fearing paternalism and conflict of interest. But the potential for conflict is not unique to physicians, and patients may have compelling reasons to prefer that their doctor make decisions on their behalf. Managing potential conflicts serves patients better than denying them the right to choose who will make health care decisions for them when they are no longer competent.  相似文献   
996.
Substantial neuronal loss in the superior frontal gyrus in patients who have died of AIDS have been reported previously. This investigation examined the distribution of neuronal loss in three other neocortical areas and, alteration in neuronal volume in four neocortical areas. This was carried out using two stereological probes, the "disector" and the "nucleator". These recently developed methods provide estimations, regardless of size and shape, in real three-dimensional space, and are more efficient than conventional quantitation. The study was performed on 12 HIV infected individuals and nine controls. The HIV group had no neuropathological evidence of opportunistic infections or neoplasms, five had HIV encephalitis and the remaining seven had only minimal pathology. There was significant neuronal loss of 30% (p = 0.018) in the calcarine cortex (primary visual area), and loss of 18% in the superior parietal lobule which just failed to reach significance. This loss was not related to the presence of HIV encephalitis. The mean neuronal volume was increased in the occipital area by 29% (p = 0.028) and the frequency of large neurons (over 2000 microns 3) doubled in the frontal (p < 0.05) and parietal (p < 0.02) areas. The results confirm the hypothesis that HIV infection is associated with neuronal injury and death, and suggest that increase in neuronal size may be a feature of the cytopathology of this condition.  相似文献   
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The Occupational Safety and Health Administration (OSHA) is in the process of developing a health standard to protect workers by reducing occupational exposure to hepatitis B virus, human immunodeficiency virus, and other bloodborne pathogens. This article reviews the history of the standard, the steps involved in OSHA standard development, and--most specifically--how the dental professional can participate in this process.  相似文献   
999.

Purpose

To elucidate the impact of renal parenchymal loss and the ischemic reperfusion injury (RI) on the renal function after laparoscopic partial nephrectomy (LPN) under warm ischemia (WI).

Methods

Thirty-five patients with a single polar renal mass ≤4 cm and normal contralateral kidney underwent LPN. Transperitoneal LPN with WI using en bloc hilar occlusion was performed. The total differential renal function (T-DRF) using 99mTc-dimercaptosuccinic acid was evaluated preoperatively and postoperatively over a period of 1 year. A special region of interest (ROI) was selected on the non-tumorous pole of the involved kidney, and was compared with the same ROI in the contralateral kidney. The latter comparison was defined as partial differential renal function (P-DRF). Any postoperative decline in the P-DRF of the operated kidney was attributed to the RI. Subtraction of the P-DRF decline from the T-DRF decline was attributed to the parenchymal loss caused by the resection of the tumor and suturing of the normal parenchyma.

Results

The mean WI time was 22 min, and the mean weight of resected specimen was 18 g. The mean postoperative eGFR declined to 87 ml/min/1.73 m2 from its baseline mean value of 97 ml/min/1.73 m2 (p value = 0.075). Mean postoperative T-DRF and P-DRF of the operated kidney declined by 7 and 3 %, respectively.

Conclusions

After LPN of small renal mass, decline in renal function is primarily attributed to parenchymal loss caused by tumor resection and suturing of the normal parenchyma rather than the RI.
  相似文献   
1000.
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