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991.
The parahippocampal gyrus, located at the medial temporal lobe, is a key structure in declarative memory processing. We have analyzed the general organization of the parahippocampal gyrus in the baboon, a nonhuman primate species relatively close to human. This region is rostrocaudally made up of the temporopolar, perirhinal, entorhinal (divided into seven subfields) and posterior parahippocampal (areas TH and TF) cortices. The basic analysis has been performed in three brains, serially sectioned and stained with thionin, myelin stain, acetylcholinesterase and parvalbumin, to determine cytoarchitectonic boundaries. Borders of all subfields were charted onto camera lucida drawings, and two-dimensional maps of the surface and topography of the parahippocampal gyrus were made. Finally, the limits of each parahippocampal area were then transposed on corresponding MR images (commonly used for in vivo PET or functional MRI activation studies) of two animals for precise identification. The general cytoarchitectonic features of the baboon parahippocampal gyrus are similar to macaques, but the size of temporopolar cortex and the laminar organization of perirhinal and posterior parahippocampal cortices resemble humans more than macaque species. In conclusion, the size and structure of the baboon parahippocampal cortex makes this species very appropriate for experimental studies on memory function.  相似文献   
992.
BACKGROUND: Studies have shown that racial and socioeconomic differences lead to inequality in access to health care. It is unknown whether insurance status and race affect the choice of surgical treatment for patients presenting with appendicitis. STUDY DESIGN: Patients with primary ICD-9 procedure codes for laparoscopic and open appendectomy were selected from the 1998, 1999, and 2000 Nationwide (US) Inpatient Samples. The primary predictor variables were insurance status (private, Medicare, Medicaid, other) and race (Caucasian, African American, Hispanic, other). Multiple logistic regression models were used to assess whether insurance status and race are associated with the choice of surgical procedure for patients presenting with appendicitis. RESULTS: Discharge abstracts of 145,546 patients were used for our analyses. There were 32,407 patients (22.3%) who underwent laparoscopic appendectomy and 113,139 patients (77.7%) who had open appendectomy. Although 24.2% of privately insured patients underwent laparoscopic appendectomy, only 16.9% of Medicare patients, 17.4% of Medicaid patients, and 19.6% of patients in the "other" insurance category were treated using the laparoscopic procedure (p < 0.001). Caucasian patients underwent laparoscopic surgery in 24.8%, African Americans in 18.6%, Hispanics in 19.6%, and other ethnicities in 18.8% of patients (p < 0.001). Compared with the Medicaid subset, and after adjusting for potential confounders such as age, gender, race, patient comorbidity, median ZIP code income, hospital location and teaching status, and presence of abscess or perforation, privately insured patients (odds ratio [OR] = 1.26, 95% [CI [1.20, 1.33], p < 0.001) and Medicare patients (OR = 1.17, 95% CI [1.05, 1.30], p = 0.004) were significantly more likely to undergo laparoscopic surgery. Caucasian patients (OR = 1.42, 95% CI [1.33, 1.51], p < 0.001) and Hispanics (OR = 1.12, 95% CI [1.04, 1.20], p = 0.002) were significantly more likely to have laparoscopic appendectomy, compared with African Americans, even after adjusting for the previously mentioned confounders and insurance status. CONCLUSIONS: Even after adjusting for potential confounders, insurance status and race are marked independent predictors of having laparoscopic surgery in patients treated for appendicitis in this sample.  相似文献   
993.
Sánchez-Ortiz RF  Pettaway CA 《Urologic oncology》2004,22(3):236-44; discussion 244-5
In patients with squamous carcinoma of the penis, the presence and extent of metastases involving the inguinal nodes are the most important factors predictive of survival. Favorable prognostic indicators of cure in surgically treated patients in whom metastases develop include: (1) minimal nodal disease, (2) unilateral involvement, (3) no evidence of extranodal extension of cancer, and (4) absence of pelvic nodal metastases. Prophylactic lymphadenectomy in select patients at high risk for metastasis seems reasonable in lieu of prospective randomized trials because novel procedures have significantly decreased the morbidity of surgical staging. Patients with poor prognostic indicators either before or after surgery should be considered for multimodal therapy.  相似文献   
994.
995.
We determined the prevalence of hepatitis C virus (HCV) in hemodialysis patients by antibody testing and HCV RNA determination by PCR. A total of 149 patients with kidney failure with replacement therapy were tested. The prevalence of anti-HCV was 6.7% (10 of 149 patients), and viremia was detectable in 8 of 149 (5%) patients. Three of 149 patients (2%) were anti-HCV negative with detectable HCV RNA.  相似文献   
996.
The objective of our study was to evaluate parameters influencing the germination of Aspergillus conidia. Inoculum concentration and age significantly influenced germination. Different incubation temperatures revealed significant differences among Aspergillus species. The internal human milieu provides the ideal conditions for the development of invasive disease by Aspergillus fumigatus but restricts invasion by Aspergillus flavus and Aspergillus niger.  相似文献   
997.
998.
Invasive fungal rhinosinusitis in immunocompromised patients   总被引:2,自引:0,他引:2  
INTRODUCTION: Invasive fungal rhinosinusitis (IFR) is one of the most important causes of morbidity and mortality in immunocompromised patients, principally those with cellular immunodeficiency, with mortality ranging from 50 to 80%. Prophylaxis and early diagnosis increase the chances of successful treatment. STUDY DESIGN: Clinical prospective randomized study. AIM: To present cases of IFR and to compare them with data reported in the literature. MATERIAL AND METHODS: Analysis of eleven cases of IFR confirmed by pathologist examination. RESULTS: Aspergillus was found to be the most prevalent pathogen. Symptoms ranged from high fever in most cases to nasal discharge, ulceration of the nasal mucosa, headache and periorbital edema. CONCLUSION: The combination of amphotericin B and endoscopic surgery, associated or not with Caldwell-Luc surgery, showed good results. The use of liposomal amphotericin B also presented a satisfactory outcome.  相似文献   
999.
1000.
OBJECTIVES: Analysis of the effect of edelfosine, ilmofosine and miltefosine on Leishmania amazonensis and of potential targets of these lysophospholipid analogues. METHODS: Quantification and ultrastructural analysis of the effect of lysophospholipid analogues on promastigote forms and on infected peritoneal macrophages, and flow cytometry analysis of treated promastigotes labelled with propidium iodide and rhodamine 123 (Rh123). RESULTS: The lysophospholipid analogues presented potent antiproliferative activity with IC50/3 days of 1.9-3.4 microM for promastigotes and 4.2-9.0 microM for intracellular amastigotes. Treatment with these analogues in Schneider medium for 1 day led to a dose-dependent decrease in Rh123 fluorescence, an effect more accentuated in edelfosine-treated parasites, suggesting interference with the potential of the mitochondrial membrane. In both forms of L. amazonensis, edelfosine induced extensive mitochondrial damage, multinucleation and, in promastigotes, also led to plasma membrane alterations, formation of autophagic structures and membranous arrangements inside the flagellar pocket. CONCLUSIONS: The alkylglycerophosphocholines edelfosine and ilmofosine were more active than the alkylphosphocholine miltefosine against promastigotes and intracellular amastigotes of L. amazonensis, and ultrastructural and flow cytometry data indicate the mitochondrion as a target of edelfosine.  相似文献   
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