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991.
992.
BACKGROUND: Hippocampal volumes obtained from a group of medication-free, remitted subjects with recurrent major depressive disorder (MDD) were compared against corresponding measures from healthy controls. METHODS: Thirty-one subjects with recurrent MDD in full remission, and 57 healthy controls underwent high resolution magnetic resonance imaging (MRI) on a GE 3T scanner. Eight patients with MDD were medication-naive, and twenty-three MDD patients were off antidepressant medications for a mean of 30 months at the time of the MRI study. RESULTS: Patients showed smaller total and posterior hippocampal volume relative to controls. Anterior hippocampal volume did not differ between patients and controls. CONCLUSIONS: Recurrent depression is associated with smaller hippocampal volume which is most prominent in the posterior hippocampus. Smaller hippocampal volume appears to be a trait characteristic for MDD.  相似文献   
993.

Introduction

Soft tissue deposits is tumorous islands apart from lymph nodes and occasionally diagnosed in neck dissection specimens. Their importance has begun to be recognized, however, their value has not been investigated in laryngeal cancer as a single tumor site.

Objective

To investigate the prognostic value of soft tissue deposits in patients with laryngeal carcinoma.

Methods

Medical records of 194 patients with laryngeal carcinoma who were treated primarily by surgery and neck dissection were reviewed. Prognostic significance of soft tissue deposits was assessed along with other clinical and pathological findings. Recurrence rates, overall and disease-specific survival rates were examined.

Results

The incidence of soft tissue deposits was found to be 7.2% in laryngeal carcinoma. N stage was more advanced in patients who had soft tissue deposits. Regional recurrence rate was higher and disease specific and overall survivals rates were significantly lower in patients with soft tissue deposits in univariate analysis. However, in multivariate analysis, soft tissue deposits were not found as an independent risk factor.

Conclusion

In laryngeal carcinoma, soft tissue deposits was diagnosed in patients with more advanced neck disease and their significance was lesser than other factors including extranodal extension.  相似文献   
994.
995.
Injury mechanisms activated by the hemodynamic adaptations to nephron loss are considered to represent a final common pathway that underlies the progressive nature of chronic renal disease. In this article, we review experimental evidence that the induction of cell adhesion molecule, cytokine and profibrotic growth factor gene expression and the resultant renal infiltration by inflammatory cells, especially macrophages, are important components of these common pathway mechanisms. Interventions aimed at inhibiting these mechanisms may offer new treatments for slowing or arresting the progression of chronic renal disease.  相似文献   
996.
Summary The oncoprotein encoded by mutantras genes is initially synthesized as a cytoplasmic precursor which requires posttranslational processing to attain biological activity; farnesylation of the cysteine residue present in the CaaX motif located at the carboxy-terminus of all Ras proteins is the critical modification. Once farnesylated and further modified, the mature Ras protein is inserted into the cell's plasma membrane where it participates in the signal transduction pathways that control cell growth and differentiation. The farnesylation reaction that modifies Ras and other cellular proteins having an appropriate CaaX motif is catalyzed by a housekeeping enzyme termed farnesyl-protein transferase (FPTase). Inhibitors of this enzyme have been prepared by several laboratories in an effort to identify compounds that would block Ras-induced cell transformation and thereby function as Ras-specific anticancer agents. A variety of natural products and synthetic organic compounds were found to block farnesylation of Ras proteinsin vitro. Some of these compounds exhibit antiproliferative activity in cell culture, block the morphological alterations associated with Ras-transformation, and can block the growth of Ras-transformed cell lines in tumor colony-forming assays. By contrast, these compounds do not affect the growth or morphology of cells transformed by the Raf or Mos oncoproteins, which do not require farnesylation to achieve biological activity. The efficacy and lack of toxicity observed with FPTase inhibitors in an animal tumor model suggest that specific FPTase inhibitors may be useful for the treatment of some types of cancer.Presented at the symposium "New Approaches in the Therapy of Breast Cancer", Georgetown University Medical Center, Washington DC, October 1994, generously supported by an education grant from Bristol-Myers Squibb.  相似文献   
997.
998.
Primary hyperparathyroidism (PHPT) has been considered a cause of insulin resistance (IR) and impaired glucose metabolism. However, there are conflicting results related with the recovery of insulin resistance in patients with PHPT following curative parathyroidectomy. Our aim is to evaluate the effects of curative parathyroidectomy on IR in patients with PHPT. This is a prospective interventional study. Twenty-one consecutive patients with symptomatic PHPT were included into the study. All patients underwent parathyroidectomy. Fasting serum glucose, calcium, phosphorous, parathormone, plasma insulin, and vitamin D levels were measured both at baseline and 2 months after parathyroidectomy. Insulin resistance was calculated by homeostasis of model assessment-insulin resistance (HOMA-IR). Two months after curative parathyroidectomy, serum levels of calcium (p?=?0.001), PTH (p?<?0.001), insulin (p?=?0.003), and HOMA-IR (p?=?0.003) decreased, while phosphorous levels increased (p?=?0.001). During this period, no changes were observed at vitamin D and glucose levels. We concluded that curative parathyroidectomy decreases HOMA-IR index in patients with PHPT. Studies with larger population and longer follow-up period are required to confirm our results.  相似文献   
999.
With important social and economic consequences, spinal cord injuries (SCIs) still exist among major health problems. Although many therapeutic agents and methods investigated for the treatment of acute SCI, only high dose methylprednisolone (MP) is being used currently in practice. Due to the serious side effects, high dose systemic MP administration after SCI is a critical issue that is mostly considered controversial. In our study, it is aimed to develop a nanoparticle-gel combined drug delivery system for localization of MP on trauma site and eliminating dose-dependent side effects by lowering the administered dose. For this purpose, methyl prednisolone sodium succinate (MPSS) loaded polycaprolactone based nanoparticles were developed and embedded in an implantable fibrin gel. The effects of MPSS delivery system are evaluated on an acute SCI rat model, by quantification the levels of three inflammatory cytokines (interleukin-1β, interleukin-6 and caspase-3) and assessment of the damage on ultrastructural level by transmission electron microscopy. Developed NP-gel system showed very similar results with systemic high dose of MPSS. It is believed that developed system may be used as a tool for the safe and effective localized delivery of several other therapeutic molecules on injured spinal cord cases.  相似文献   
1000.
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