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91.
Background Factors prognostic for survival in patients with locally recurrent extremity soft tissue sarcomas (STS) are poorly defined, thus making it difficult to identify high-risk patients who may benefit from adjuvant therapy.Methods A total of 1421 patients underwent surgical treatment for primary extremity STS at a single institution between 1982 and 2002. Of these, 179 (13%) patients underwent complete surgical resection of an isolated local recurrence and were the subjects of this study. Clinicopathologic factors from both the primary tumor and the local recurrence were analyzed.Results The median interval to initial local recurrence was 16 months: 65% developed a local recurrence by 2 years and 90% by 4 years. Only four patients who presented with a low-grade primary tumor progressed to a high-grade local recurrence. Independent prognostic factors for disease-specific survival after local recurrence were a high histological grade (hazard ratio, 5.1; P = .0004), a large local recurrence tumor size (hazard ratio, 1.5; P = .0001), and a short local recurrence–free interval (hazard ratio, 1.6; P = .0001). Patients who developed a local recurrence >5 cm in 16 months (n = 44; 0 low grade) had a 4-year disease-specific survival of 18%, compared with 81% for patients who developed a local recurrence 5 cm in >16 months (n = 46; 11 low grade).Conclusions Histological grade, local recurrence size, and local recurrence–free interval are independently predictive of survival in patients with locally recurrent extremity STS. A large local recurrence that develops in a short interval indicates a biologically aggressive tumor with a high tumor-specific mortality. Patients who develop such recurrences are ideal subjects for systemic neoadjuvant therapy trials.  相似文献   
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93.
Phagocytosis by neutrophils and monocytes constitutes the main defense mechanism against bacterial challenges in periodontitis. Phagocytosis by neutrophils has already been evaluated, whereas phagocytic function of monocytes has hardly been addressed so far.

Objectives

The aim of this study was to assess phagocytosis by neutrophils and monocytes in periodontitis.

Material and Methods

The sample included 30 subjects with severe periodontitis and 27 control subjects without periodontal disease. The phagocytic index (PhI) was calculated as the mean number of adhered/ingested Saccharomyces cerevisiae per phagocytozing monocyte or neutrophil multiplied by the percentage of phagocytes involved in phagocytosis.

Results

A significant reduction in phagocyte functions was observed in individuals with periodontitis. The median of PhI of neutrophils using non-sensitized S. cerevisiae was 3 for the control group, and 1.5 for the periodontitis group (p=0.01, Mann-Whitney test). The median of PhI of monocytes with non-sensitized S. cerevisiae was 26.13 for the control group, and 13.23 for the periodontitis group (p=0.03, Mann Whitney test). The median of PhI of monocytes assessed with sensitized S. cerevisiae was 97.92 for the control group and 60.1 for the periodontitis group (p=0.005, t-test).

Conclusion

The data demonstrated a reduction in the function of phagocytes, suggesting a decrease in immune defenses in periodontitis.  相似文献   
94.
The aim of this study was to determine the effect of the oral environment on the corrosion of dental alloys with different compositions, using electrochemical methods. The corrosion rates were obtained from the current-potential curves and electrochemical impedance spectroscopy (EIS). The effect of artificial saliva on the corrosion of dental alloys was dependent on alloy composition. Dissolution of the ions occurred in all tested dental alloys and the results were strongly dependent on the general alloy composition. Regarding the alloys containing nickel, the Ni-Cr and Ni-Cr-Ti alloys released 0.62 mg/L of Ni on average, while the Co-Cr dental alloy released ions between 0.01 and 0.03 mg/L of Co and Cr, respectively.The open-circuit potential stabilized at a higher level with lower deviation (standard deviation: Ni-Cr-6Ti = 32 mV/SCE and Co-Cr = 54 mV/SCE). The potenciodynamic curves of the dental alloys showed that the Ni-based dental alloy with >70 wt% of Ni had a similar curve and the Co-Cr dental alloy showed a low current density and hence a high resistance to corrosion compared with the Ni-based dental alloys. Some changes in microstructure were observed and this fact influenced the corrosion behavior for the alloys. The lower corrosion resistance also led to greater release of nickel ions to the medium. The quantity of Co ions released from the Co-Cr-Mo alloy was relatively small in the solutions. In addition, the quantity of Cr ions released into the artificial saliva from the Co-Cr alloy was lower than Cr release from the Ni-based dental alloys.  相似文献   
95.
OBJECTIVE: To evaluate the association between different components of smoking history and the clinical severity of psoriasis. DESIGN: A hospital-based cross-sectional study. SETTING: Inpatient wards of a hospital for skin diseases in Rome, Italy. PATIENTS: A total of 818 adults with psoriasis. MAIN OUTCOME MEASURE: The Psoriasis Area and Severity Index was used to assess the clinical severity of psoriasis between February 21, 2000, and February 19, 2002. RESULTS: After adjustment for potential confounders (sex, age, body mass index, psychological distress, family history of psoriasis, duration of psoriasis disease, and alcohol consumption), high intensity of smoking (>20 cigarettes daily) vs a lower level of consumption (< or =10 cigarettes daily) was associated with a more than 2-fold increased risk of clinically more severe psoriasis (odds ratio [OR], 2.2; 95% confidence interval [CI], 1.2-4.1). Cigarette-years, measured as the product of the intensity and duration (years) of smoking, significantly increased the risk of clinically more severe psoriasis after adjustment for confounding factors (OR,1.3; 95% CI, 1.0-1.6, for a 600-U increase in cigarette-years). Separate analyses for men and women showed that the effect of cigarette-years was stronger for women (OR, 1.8; 95% CI, 1.2-2.6, for a 400-U increase in cigarette-years) than for men (OR, 1.2; 95% CI, 0.9-1.6, for a 700-U increase in cigarette-years). CONCLUSION: Smoking is associated with the clinical severity of psoriasis and highlights the importance of smoking cessation in patients with psoriasis.  相似文献   
96.
Ocular non-Hodgkin's lymphoma is a rare condition that can involve the retina, the vitreous and the optic nerve. It can occur alone or can be associated with lymphoma of the central nervous system and a frequent manifestation is a posterior uveitis of difficult treatment. This kind of ocular tumor is difficult and a challenge to diagnosis. We describe a case of non-Hodgkin's intraocular B-cell lymphoma in a 47-year-old woman who had a posterior uveitis as the first manifestation. We emphasize the importance of a careful investigation and of the general clinical examination since this is the most common type in the eye. We expect to call the attention to this disease that many times appears in an unspecific form with unspecific symptoms.  相似文献   
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99.
Trichoblastomas (TBs) are benign skin tumors recapitulating the differentiation of hair follicles. Several pathologic variants have been described, including the rare pigmented TB. We report a deeply pigmented nodular tumor excised on the scalp of a 32-year-old African woman, which was clinically suggestive of blue nevus or melanoma. Histologically, the tumor presented features of TB, remarkable by virtue of heavy melanin deposits found within and around tumor nests. By immunohistochemistry, abundant dendritic melanocytes with features of hair follicle melanocytes (expression of S100 protein, tyrosinase, and, most importantly, gp100/HMB-45) were found within the tumor masses. By analogy with melanoacanthoma, a tumor consisting of a combined proliferation of epidermal keratinocytes and melanocytes, we called this tumor "melanotrichoblastoma" and view it as a peculiar variant of (pigmented) TB.  相似文献   
100.

Study Objectives:

Evaluation of modafinil effects on the inhibitory avoidance task (IA).

Design:

Rats were trained on a multiple trial IA task after receiving modafinil or vehicle injections. In experiment 1 they were trained with a weak protocol under baseline condition and in experiment 2, with a stronger protocol under sleep-deprivation condition.

Results:

In experiment 1 modafinil improved rats'' acquisition whereas the retention test remained unaffected. In Experiment 2 modafinil did not interfere with training performance, but the lower dose prevented the retention impairment in sleep-deprived animals.

Conclusions:

Modafinil is able to improve acquisition in normal rats and reverse the long-term memory impairment induced by sleep-deprivation.

Citation:

Moreira KM; Ferreira TL; Hipolide DC; Fornari RV; Tufik S; Oliveira MGM. Modafinil prevents inhibitory avoidance memory deficit induced by sleep deprivation in rats. SLEEP 2010;33(7):990-993.  相似文献   
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