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991.
We report two cases of Serratia marcescens infection at the sites of spinal fractures and emphasise the fact that neurological deterioration soon after spinal fracture may be due to acute vertebral osteomyelitis.  相似文献   
992.
L J DeGroot  E L Kaplan 《Surgery》1991,110(6):936-9; discussion 939-40
The role of elective completion thyroidectomy after lobectomy for differentiated thyroid cancers remains controversial. The potential benefit of tumor removal by the second procedure is considered by some to be overbalanced by a prohibitive operative morbidity rate. During a 20-year period at the University of Chicago Medical Center, 26 patients underwent completion thyroidectomy within a 6-month period of the original thyroid operation. This group represents 8% of the 326 patients who underwent surgery during that time for differentiated thyroid cancer (269 papillary and 57 follicular). Of the 26 patients, 18 had papillary and eight had follicular cancers. The average size was 2.5 cm, with 24 of 26 being greater than 1 cm in diameter. At the first operation, 81% of tumors were intrathyroidal. Eight percent had lymph node metastases and 12% manifested local invasion. Tumor was found in eight (31%) of 26 of the reoperative specimens. The incidence of tumor did not vary by histologic type but did differ according to the extent of the original operation. Cancer was found in 50% (three of six) of those who had undergone previous partial lobectomy, in 33% (five of 15) of those after a total lobectomy, and in none of five who had undergone a prior bilateral (although incomplete) thyroid resection. One permanent recurrent nerve injury occurred at the first operation. No additional recurrent nerve injuries or hypoparathyroidism occurred as a result of the second operation. Finally, no disease characteristic of the initial tumor (e.g., size, clinical class, tumor capsular invasion, multifocality, thyroiditis, or extrathyroidal tumor invasiveness) predicted the presence or absence of tumor on the second side. We conclude that completion thyroidectomy is appropriate for patients with lesions 1 cm or greater who have undergone lobectomy or less at the original operation, because 40% of such patients would be expected to have residual cancer. With care, this operation can be performed with minimal morbidity.  相似文献   
993.
CD-1 mice were treated with caffeine-sodium benzoate solution (caffeine doses: 0, 5, 15 or 30 mg/kg i.p.) to determine plasma and brain concentrations, effects on benzodiazepine receptor binding based on specific uptake of a high affinity ligand, and locomotor activity. There was a linear relationship between caffeine dose and mean brain or plasma concentrations, but concentrations varied considerably at any given dose. There were also linear relationships between plasma and brain concentrations of caffeine and each metabolite, with caffeine itself having the greatest brain:plasma uptake ratio. Benzodiazepine receptor binding was determined based on uptake of the benzodiazepine receptor ligand [3H]Ro15-1788, 3 microCi i.v. given 40 min after caffeine (30 mg/kg). Nonspecific binding was measured in animals pretreated with saturating doses of clonazepam. Specific uptake (measured by subtracting nonspecific from total [3H] Ro15-1788 uptake) increased significantly with caffeine as opposed to vehicle treatment in the cortex, hippocampus and hypothalamus. Brain caffeine concentrations associated with enhanced uptake were between 11 to 17 micrograms/g. Total locomotor activity and activity at 60 min, measured by an infrared sensor system, increased progressively with brain caffeine concentrations when comparing the following groups: 0, 2 to 9 micrograms/g of brain and 9 to 20 micrograms/g. Animals with brain concentrations exceeding 20 micrograms/g showed a decline in both measures but activity was significantly greater than placebo. In conclusion, brain caffeine concentrations between 9 to 20 micrograms/g are associated with increases in specific ligand uptake and motor activity.  相似文献   
994.
Abstract: Hemolytic uremic syndrome (HUS) can be seen as a result of disseminated cancer, as a consequence of chemotherapy, or in association with bone marrow transplantation (BMT). Further distinction can be made when the clinical presentation is that of an acute, fulminant course with rapidly progressive renal failure or that of a sub‐acute form with a slow progression of renal involvement. Each of the different etiologies (cancer, chemotherapy, or BMT) and each of the two basic clinical presentations has its own prognosis. There are no randomized, controlled studies to elucidate the role of therapeutic apheresis for cancer‐related HUS. Hemolytic uremic syndrome related to disseminated cancer is most often a terminal event and is not commonly treated with apheresis procedures, although there are anecdotal reports that plasma exchange may be beneficial. Chemotherapy and drug‐related HUS have a prognosis that is strongly dependent on the severity of the presentation, but even in the most severe cases may respond to either immunoadsorption or plasma exchange with fresh frozen plasma (FFP). Finally, BMT‐related HUS has a poor prognosis but may respond to immunoadsorption, plasma exchange, or a combination of the two.  相似文献   
995.
996.

Background  

Approximately 35% of PBC patients have progressive disease despite treatment with UDCA.  相似文献   
997.
AIM: To determine whether increased bilirubin production, reflected by blood carboxyhaemoglobin (COHb) values, is responsible for hyperbilirubinaemia in cases of Down's syndrome with no obvious cause for excessive jaundice. METHODS: Blood was sampled on the third day of life for COHb, total haemoglobin (tHb), and serum total bilirubin, from 19 consecutively born neonates with Down's syndrome (a subset of 34 term babies), who had developed hyperbilirubinaemia (serum bilirubin >/= 256 micromol), and from 32 term controls. COHb, measured by gas chromatography, was corrected for inspired CO (COHbc) and expressed as a percentage of tHb. RESULTS: Significantly more of the Down's syndrome subset developed hyperbilirubinaemia than the controls (10/19 (52%) vs 7/32 (22%), relative risk 2.4, 95% confidence intervals (CI) 1.10 to 5.26). Third day serum bilirubin values (mean (SD)) were higher in the Down's syndrome neonates than in controls (214 +- 63 micromol/l vs 172 +- 54 micromol/l, respectively, p=0.015). Mean (SD) COHbc values were significantly higher in the Down's syndrome neonates than in controls (0.92 +- 0. 24% vs 0.63 +- 0.17%; p<0.0001). However, Down's syndrome neonates who became hyperbilirubinaemic had similar COHbc values to those who did not (0.87 +- 0.26% and 0.95 +- 0.23%, respectively). These values contrast with those of the controls, in whom a significant increase in COHbc was associated with hyperbilirubinaemia (0.74 +- 0. 15% vs 0.60 +- 0.16%, respectively; p<0.05). tHb values were similar in both groups. CONCLUSIONS: Down's syndrome neonates had a greater risk of hyperbilirubinaemia, and higher COHbc values, than controls. However, excessive bilirubin production could not be exclusively responsible for the hyperbilirubinaemia. By inference, decreased bilirubin elimination probably plays a greater part in its pathogenesis than in controls. Down's syndrome neonates may have abnormal erythropoiesis, leading to increased haem turnover.  相似文献   
998.
999.
1000.
In order to identify changes in 31P nuclear magnetic resonance (NMR) spectra associated with multiple drug resistance (MDR), a number of wild type and drug-resistant cancer cell lines were studied. The resistant cells included cells selected with various drugs, mainly Adriamycin, as well as cells transfected with the human multidrug resistance gene (MDR1 gene), which encodes P-glycoprotein. In most cases, 31P NMR spectra were significantly different from those of parental, drug-sensitive lines. The spectra of resistant cells generally indicated increased levels of ATP and phosphocreatine in the cytoplasm. These changes are compatible with the increased glucose utilization rate previously described for resistant cells. Major changes were also observed in the levels of glycerophosphocholine and glycerophosphoethanolamine. Changes in cellular metabolism reflected by 31P NMR spectra depend on the drug used to select the cells for MDR. The direction of these changes was not consistent for all cell lines studied and could not be directly attributed to expression of P-glycoprotein, suggesting that the changes may be related to alterations in metabolism and membrane function associated with other mechanisms of MDR. The results demonstrate the suitability of 31P NMR for studies of biochemical changes associated with MDR. The toxicity of 2-deoxyglucose, a glucose antimetabolite, was investigated in addition to the NMR studies and was found to be consistently higher in multidrug-resistant cells than in the parental drug-sensitive lines. For MCF-7 breast cancer cells, where several sublines with different levels of resistance were available, the toxicity was highest for the most resistant lines.  相似文献   
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