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991.
992.
The authors examined the motor effects of 2 weeks of paroxetine, a serotonin reuptake inhibitor (SSRI), and placebo on responses to 2-hour levodopa infusions in 14 subjects with Parkinson disease. Paroxetine did not affect tapping scores or dyskinesia. Baseline walking speed (preinfusion) increased on paroxetine, often associated with an increased subjective perception of worsened balance. 相似文献
993.
994.
Exposure to violence and parenting as mediators between poverty and psychological symptoms in urban African American adolescents 总被引:1,自引:0,他引:1
Grant KE McCormick A Poindexter L Simpkins T Janda CM Thomas KJ Campbell A Carleton R Taylor J 《Journal of adolescence》2005,28(4):507-521
The present study builds on past research that has found support for a conceptual model in which poverty is linked with adolescent psychological symptoms through economic stressors and impaired parenting. The present study examined this model in a sample of urban African American mothers and their adolescent children. In addition, an alternative hypothesis was examined: that exposure to community violence mediates the relation between poverty and psychological symptoms in urban youth. Limited support was found for a model in which poverty is linked with internalizing symptoms through exposure to community violence and with externalizing symptoms through economic stressors and inconsistent discipline. Interpretations, limitations, and directions for future research are outlined. 相似文献
995.
This article describes findings from review of tobacco industry documents regarding promotion of tobacco to the military, and efforts to influence Department of Defense policies regarding the use and sale of tobacco products. The documents reveal that the industry has targeted the military for decades for reasons including: (1) the volume of worldwide military personnel; (2) the opportunity to attract young men who fit a specific socioeconomic and cultural profile; (3) potential carryover of profits to civilian markets; and (4) the unusual price structure of commissaries and exchanges. The industry used distinctive promotion methods such as in-store merchandising, sponsorships, and even brand development to target the military, both in the United States and abroad during times of conflict. Legislative activity to protect tobacco promotion to this vulnerable population was carried out in response to smoking policy changes proposed by the Department of Defense. The tobacco industry has contributed to the high prevalence of smoking in the military and among veterans. 相似文献
996.
Radiofrequency ablation of hepatocellular carcinoma: treatment success as defined by histologic examination of the explanted liver 总被引:20,自引:0,他引:20
Lu DS Yu NC Raman SS Limanond P Lassman C Murray K Tong MJ Amado RG Busuttil RW 《Radiology》2005,234(3):954-960
PURPOSE: To retrospectively evaluate the effectiveness of radiofrequency (RF) ablation of hepatocellular carcinoma (HCC) by using histologic examination of the explanted liver. MATERIALS AND METHODS: The study was approved by the medical center Institutional Review Board, with waiver of informed consent. Forty-seven HCC nodules in 24 patients (18 men, six women; age range, 33-71 years; mean age, 56 years) were treated with single or double RF ablation sessions prior to liver transplantation. Histologic data from hematoxylin-eosin staining of explanted liver specimens were retrospectively reviewed to determine treatment success, which was defined as the absence of residual or recurrent viable carcinoma cells at treatment site. Tumor size and the presence of large (> or =3 mm) abutting vessels that were observed during imaging were tested as potential predictors of treatment success or failure (Fisher exact test). In patients who underwent postablation computed tomographic (CT) or magnetic resonance (MR) imaging within 3 months prior to transplantation (21 patients with 44 tumors), imaging results were analyzed for sensitivity and specificity of residual or recurrent tumor by using histologic data as the reference standard. RESULTS: Thirty-five (74%) of 47 ablated tumors, including 29 (83%) of 35 tumors less than 3 cm, were found to be successfully treated on the basis of histologic findings after a mean interval of 7.5 months between RF ablation and transplantation. Nodules that were successfully treated had mean maximal diameter of 2.0 cm, and nodules that were unsuccessfully treated had mean maximal diameter of 3.1 cm (P=.014). Seven (47%) of 15 perivascular lesions were successfully treated whereas 28 (88%) of 32 nonperivascular lesions were successfully treated (P <.01). Imaging correlation showed 100% (33 of 33) specificity and 36% (four of 11) sensitivity of postablation CT and MR imaging for the depiction of residual or recurrent tumor. CONCLUSION: Histologic evidence directly validates RF ablation as an effective treatment of small (<3 cm) HCC. 相似文献
997.
Hope A Hjelle J Aanderud L Aakvaag A 《Aviation, space, and environmental medicine》2005,76(7):655-660
BACKGROUND: Bodyweight (BW) losses up to 5 kg have been observed during diving with the open hot-water suit (HWS). The objective of these dives was to study the hormonal, hematological, and renal effects of dehydration during shallow HWS diving. METHODS: In series 1, four divers dove for 3.5 h each day for 7 d. In series 2, 12 divers dove to 6-8 msw for 1, 2, and 4 h. Blood and urine samples, BW measurements, oral temperature, and thermal stress indices were collected. RESULTS: Average deltaBW (+/- SD) for the 28 dives in series 1 was 1.5 +/- 0.8 kg, and the largest BW reductions were 3.2 and 3.0 kg, corresponding to 3.7 and 4.7% of BW. Changes in thermal stress, hemoglobin, hematocrit, aldosterone, and electrolyte excretion correlated with BW reduction. In series 2, average BW reductions were 0.46 +/- 0.27, 0.96 +/- 0.38, and 1.55 +/- 0.59 kg during 1-, 2-, and 4-h dives. BW reduction correlated significantly with thermal stress (p < 0.01). Aldosterone increased after 1 and 2 h and plasma renin activity was unchanged. Atrial natriuretic peptide increased in all dives (p < 0.01) and arginine vasopressin increased in the 4-h dives (p < 0.05). The 7.2% decrease in plasma volume, the increases in hemoglobin, hematocrit and serum proteins, and an unchanged plasma osmolality indicate an isotonic dehydration after the 4-h dives. CONCLUSIONS: BW loss during HWS diving is mainly caused by sweating. Dives of 4 h produce an isotonic dehydration and a break for fluid intake is, therefore, recommended. 相似文献
998.
PURPOSE: Approximately 5 to 10% of parathyroid adenomas are located within the thin, fibrous capsule of the thyroid gland. These subcapsular adenomas can complicate minimally invasive parathyroidectomy. The small incision used in this procedure limits the view of the surgical bed. Palpation is less sensitive when the adenoma is covered by the thyroid capsule. If a subcapsular parathyroid adenoma can be identified on preoperative parathyroid scintigraphy, nuclear medicine physicians can recommend exploration of the thyroid capsule early, leading to an easier, more efficient operation. The objective of this observational study was to identify the scintigraphic appearance of subcapsular parathyroid adenomas. MATERIALS AND METHODS: A total of 109 patients with primary hyperparathyroidism underwent preoperative dual-phase Tc-99m sestamibi parathyroid scintigraphy at our tertiary care center from October 2002 to March 2004. Tc-99m pertechnetate was used as a supplemental technique when deemed necessary for optimal interpretation. Retrospective chart review identified 16 surgically proved subcapsular parathyroid adenomas. Parathyroid scintigraphy was reviewed. RESULTS: Subcapsular parathyroid adenomas tend to conform to the expected shape of the thyroid gland. In this small series, subcapsular parathyroid adenomas followed 1 of 3 patterns on lateral images: (1) focal convex distortion of the posterior wall of the thyroid, (2) polar lentiform configuration, and (3) compression of the posterior thyroid parenchyma. CONCLUSION: Subcapsular parathyroid adenomas often have a distinct appearance on scintigraphy. Preoperative identification of this type of parathyroid adenoma can direct a subcapsular surgical approach, optimizing the efficiency of the minimally invasive parathyroidectomy. 相似文献
999.
García-Ojeda PA Hardy S Kozlowski S Stein KE Feavers IM 《Infection and immunity》2004,72(6):3451-3460
Antibody (Ab) responses to polysaccharides (PS), such as Neisseria meningitidis group C PS (MCPS), are characterized as being thymus independent and are restricted with regard to clonotype and isotype expression. PS conjugated to proteins, e.g., MCPS coupled with tetanus toxoid or the diphtheria toxin derivative CRM197, elicit thymus-dependent responses. The present study developed a surface plasmon resonance approach to evaluate Ab responses to MCPS conjugate vaccines, including either O-acetylated (OAc+) or de-O-acetylated (OAc-) forms of the PS. The results were generally consistent with those obtained by enzyme-linked immunosorbent assay and showed that sera from mice immunized with conjugate vaccines contain Abs that bind more effectively to OAc+ and OAc- MCPS than sera from mice immunized with fixed bacteria. The data suggest a critical shared or overlapping epitope recognized by all the conjugate vaccine immune sera and strategies for assessing polyclonal Ab avidity. 相似文献
1000.