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1.
Gangliocytic paragangliomas are rare tumors that almost exclusively occur within the second portion of the duodenum. Although these tumors generally have a benign clinical course, they have the potential to recur or metastasize to regional lymph nodes. The case report presented here describes a 57-year-old female patient with melena, progressive asthenia, anemia, and a mass in the second-third portion of the duodenum that was treated by local excision. The patient was diagnosed with a friable bleeding tumor. The histologic analysis showed that the tumor was a 4 cm gangliocytic paraganglioma without a malignant cell pattern. In the absence of local invasion or distant metastasis, endoscopic resection represents a feasible, curative therapy. Although endoscopic polypectomy is currently considered the treatment of choice, it is not recommended if the size of the tumor is > 3 cm and/or there is active or recent bleeding. Patients diagnosed with a gangliocytic paraganglioma should be closely followed-up for possible local recurrence.  相似文献   
2.
OBJECTIVE: Alveolar distraction is a relatively novel procedure by which alveolar bone and underlying mucosa are regenerated. The low predictability of other vertical or horizontal bone regeneration methods has increased interest in this promising technique. This article was designed to review published clinical and experimental results on alveolar distraction, including basic research in other disciplines (maxillofacial and orthopedic distraction) related to or with influence on alveolar distraction. STUDY DESIGN: A review of the international literature was performed to summarize results of clinical and experimental studies on alveolar distraction and on distraction at other anatomical sites that contribute important findings on tissue biology, molecular mechanisms, and other factors that influence and participate in the alveolar distraction process. RESULTS: Research into alveolar distraction has addressed the latency phase, distraction phase, and consolidation phase, yielding highly variable results. Little experimental research has been carried out on this procedure, and most publications are clinical studies with a short follow-up period. Published studies have reported a high rate of complications, attributable to our current lack of understanding of the process. CONCLUSIONS: Definitive conclusions on alveolar distraction are hampered by the lack of clinical and experimental studies to date. Greater knowledge of the factors that influence the distraction process will lead to a more predictable and efficacious distraction technique and a better distractor design.  相似文献   
3.
L Grau 《Women & health》1988,14(3-4):75-91
Currently it is estimated that up to 25 percent of the elderly manifest symptoms of mental disorder. The recognition of the seriousness of the problem has lead to a growing body of research in the field of geriatric mental health. This paper presents an overview of early gerontological studies of life satisfaction and morale of older persons and of the two most prevalent mental health problems of the aged, depression and dementia. Mental health service delivery and utilization issues are also considered.  相似文献   
4.
The atomic rearrangement cascade that follows the electron-capture decay process in low-Z radionuclides involves X-rays which have high photoelectric interaction probabilities. When the K-shell binding energy of the ionized atom (e.g., hydrogen) is significantly lower than the energy of the X-ray photon, the detector response to a photon-equivalent energy electron and the whole photoionization process are very similar. This is not the case when the scintillator cocktail contains larger atoms (e.g., oxygen and phosphorus in Ultima Gold). For larger Z atoms, the reduced energy of the whole photoionization process is less than the reduced energy of the interacting photon due to the nonlinear effects of ionization quenching. This paper shows the convenience of including a more detailed simulation of the photoionization process in the atomic rearrangement detection model for electron-capture nuclides such as (55)Fe, (51)Cr and (54)Mn. The need for more elaborate atomic rearrangement models is a consequence of the analysis of (125)I data.  相似文献   
5.
Background Cold ischemia time and the presence of postoperative hepatic arterial thrombosis have been associated with biliary complications (BC) after liver transplantation. An ABO-incompatible blood group has also been suggested as a factor for predisposal towards BC. However, the influence of Rh nonidentity has not been studied previously. Materials Three hundred fifty six liver transplants were performed from 1995 to 2000 at our hospital. BC incidence and risk factors were studied in 345 patients. Results Seventy patients (20%) presented BC after liver transplantation. Bile leakage (24/45%) and stenotic anastomosis (21/30%) were the most frequent complications. Presence of BC in Rh-nonidentical graft–host cases (23/76, 30%) was higher than in Rh-identical grafts (47/269, 17%) (P = 0.01). BC was also more frequent in grafts with arterial thrombosis (9/25, 36% vs 60/319, 19%; P = 0.03) and grafts with cold ischemia time longer than 430 min (26/174, 15% vs 44/171, 26%; P = 0.01). Multivariate logistic regression confirmed that Rh graft–host nonidentical blood groups [RR = 2(1.1–3.6); P = 0.02], arterial thrombosis [RR = 2.6(1.1–6.4); P = 0.02] and cold ischemia time longer than 430 min [RR = 1.8(1–3.2); P = 0.02] were risk factors for presenting BC. Conclusion Liver transplantation using Rh graft–host nonidentical blood groups leads to a greater incidence of BC.  相似文献   
6.
Researchers have demonstrated that certain types of pain coping are correlated with less pain severity and disability and that there are differences between Caucasians and African-American pain patients in their use of specific coping strategies. However, the extent to which racial group differences exist in the associations between pain coping strategies and pain severity, interference, and disability is unclear. Furthermore, the role of education in these associations is uncertain. We recruited a diverse community sample of individuals with chronic pain and their spouses to examine this issue (N = 105). Participants completed the Coping Strategies Questionnaire, Multidimensional Pain Inventory, and Sickness Impact Profile. Results showed that African-American participants reported significantly more pain severity, interference, and disability and reported using diverting attention and prayer and hoping pain-coping strategies significantly more often than Caucasian participants; however, only the racial group difference in prayer and hoping remained when controlling for education. We also examined whether race and education interacted with coping strategies in relating to pain and disability. Significant three-way interactions were found for physical and psychosocial disability, suggesting that educational level should be included in analyses exploring racial group differences. The results suggest the need for pain treatments that take into account the educational and cultural context of pain. PERSPECTIVE: This article demonstrates that demographic variables such as race and education should be considered together when evaluating the effectiveness of coping with pain. The findings have the potential to enhance research and clinical practice with diverse groups.  相似文献   
7.
Reports of a dramatic decrease in tumor recurrence and regression of muscle invasive disease with oral bacillus Calmette-Guerin prompted us to conduct a randomized prospective comparison of oral bacillus Calmette-Guerin with the standard intravesical plus percutaneous therapy. Oral therapy consisted of 200 mg. Tice bacillus Calmette-Guerin 3 times each week. Intravesical and percutaneous Tice bacillus Calmette-Guerin at a dose of 50 mg. was given weekly for 6 weeks, at 8, 10 and 12 weeks, then at 6 months and every 6 months thereafter. Minimal side effects confirmed the safety of oral bacillus Calmette-Guerin. Tumor recurrence was documented in 21 of 33 oral bacillus Calmette-Guerin patients (64%) and 18 of 55 (33%) who received intravesical plus percutaneous therapy (p less than 0.002, chi-square test). We were unable to demonstrate any antitumor activity of oral bacillus Calmette-Guerin in this study.  相似文献   
8.
The treatment of neoplasia with interleukin-2 (IL-2) can be complicated by neurological deficits resembling transient Ischemic attack and stroke. We investigated whether interleukin-2 contributes to the natural course of cerebrovascular ischemia and particularly to the pathogenesis of infection-associated stroke. Plasma levels of interleukin-2 were below the level of detectability in almost all measurements. Patients with and without previous infection (n = 11, 805 ±445 U/ml vs n = 19, 824 ± 501 U/ml) did not have significantly higher levels of soluble interleukin-2 receptors than control subjects with (n = 14, 667 ± 229 U/ml) or without vascular risk factors (n = 17, 567 ± 176 U/ml). Receptor levels increased in patients during the first week after stroke (n = 15, 1157 ± 1013, p < 0.02). Levels of soluble T8 antigen (sT8) were higher in patients (n – 26, 320 ± 112 U/ml) than in healthy control subjects (n = 15, 246 ± 92 U/ml; p < 0.05) and sT8 levels increased during the first week after stroke (p < 0.05). These results reflect an immunological response to the cerebral infarct; they do not indicate a general role of the IL-2 system in the pathogenesis of ischemic stroke with or without previous infection.  相似文献   
9.
10.
Our study was designed to determine the population pharmacokinetic parameters of amikacin in intensive care unit patients and to develop a Bayesian method allowing individual estimation of pharmacokinetic parameters. A two-stage method was used for estimating the population characteristics of the pharmacokinetic parameters. Calculations of optimum doses and dosing intervals were based on individual parameters. Our results indicate that the Bayesian method is capable of estimating the individual pharmacokinetic parameters with no significant bias and good precision. Individualization of amikacin dosage was assessed 70 times in 52 patients. To determine the predictive performance of the method, observed peak and trough levels were compared with predicted values by computing precision, bias, and correlation. The amikacin dosing method was unbiased and showed a high correlation coefficient (r = 0.962) between measured and predicted drug serum concentrations. No significant differences were found between the predicted and observed peak (17.3 +/- 3.5 and 17.3 +/- 3.8 micrograms/ml, respectively) and trough (2.86 +/- 0.93 and 3.08 +/- 1.41 micrograms/ml, respectively) amikacin serum concentrations. Among the 52 patients, wide variations were observed in the pharmacokinetic parameters (Vd = 0.21-0.50 L/kg; t 1/2 = 1.1-22 h) and the daily doses (2.8-42 mg/kg/day).  相似文献   
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