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51.
Increased amounts of brown adipose tissue have been reported to occur in association with several diseases. The objective of the present study was to determine whether brown adipose tissue accumulation is related to nutritional status. Histologic sections of periadrenal tissue prospectively obtained at consecutive autopsies from 366 adults were examined. The cases were separated into three groups: malnourished (101 autopsies), normotrophic (128 autopsies), and obese (137 autopsies), according to the Quetelet index. Of these patients, 89 had brown adipose tissue accumulation, 35 were malnourished, 32 were normotrophic, and 22 were obese. The results showed a correlation between brown adipose tissue and patient nutritional status and a higher brown adipose tissue accumulation in malnourished patients. Cardiovascular disease was the most common type of illness present in the cases with brown adipose tissue accumulation.  相似文献   
52.
PURPOSE: Postoperative variables such as pain, swelling, and trismus after surgery of the impacted lower third molars are the main concerns of dental clinicians and surgeons. Many authors claim that the use of a drain could help control these variables. The purpose of this study was to evaluate the effect of the use of a tube drain in impacted lower third molar surgery. MATERIALS AND METHODS: Fifty-three patients of both genders with bilateral impacted lower third molars comprised our comparative study. The patients were divided into 2 groups: in the first the suture procedure was accomplished using a drain, and in the second the suture procedure was accomplished without a drain. The postoperative pain, swelling, and trismus were evaluated at 24 hours, 72 hours, 7 days, and 15 days. RESULTS: In the group in which the drain was used, the control of the swelling variable was statistically significant at 24 and 72 hours (P <.001) in comparison with the group in which the drain was not used. However, pain and trismus were not statistically significant at the evaluation period. CONCLUSION: The use of the drain helps to control swelling. However, it had no effect on pain or trismus.  相似文献   
53.
In a catamnestic study an analysis of the clinical results as well as of the spermatograms are reported on 545 andrological patients with "atrophy" (that means reduced testis volume) or absence of one testis and a contralaterally normal developed testis. It can be demonstrated that there do not exist any differences concerning the size and consistency of the present testis and with regard to absence or lost of one testis (hemicastration). In case of testicular atrophy exists a more disadvantageous reproductive function. In case of tumor as a reason for hemicastration the teratoma shows better conditions for the quality of the spermatograms and for reproduction. Accordingly the histological findings of the testis after hemicastration/absence are not so large in the present remained testis. In cases of one-sided orchitis the spermatogram quality is better than in one-sided varicocele with atrophy at the same side.  相似文献   
54.
The promoter region of the human GSTP1 gene contains a polymorphic short tandem repeat (STR) locus consisting of pentanucleotide repeat units (ATAAA). In this work we report the existence of a total of 26 alleles in a Caucasian population. While differences in size (ranging from one to five base pairs) were responsible for the major variation, in five size-defined classes, two alternative sequences were found. Automatic fragment sizing and sequencing analysis revealed that this polymorphism is of a highly complex nature in contrast with previous reports. A genetic population study was carried out on a random sample from Portugal showing no deviation from Hardy-Weinberg equilibrium. Somatic instability studies were also performed on gastric and thyroid tumours using this STR: no instability was detected in thyroid tumour tissues when compared with their normal counterpart but in gastric tumour tissues microsatellite instability (MSI) was detected in 9.6% of the cases and loss of heterozygosity (LOH) also in 9.6% of the cases studied. The results obtained with GSTP1 in gastric cancer were compared with previously reported data on MSI using BAT-26 and several dinucleotide repeat markers.  相似文献   
55.
In this work we have quantified soluble class I histocompatibility antigens (s-HLA) and beta 2-microglobulin (beta 2 m) in sera of HIV+ or HIV- mothers at delivery and in cord blood sera of their newborn children. The results obtained for beta 2 m show that cord blood sera of newborn children have higher concentrations than their mothers, implying that most of the beta 2 m in the newborn is self-produced as described previously. s-HLA serum concentrations in the newborn children are significantly lower than in their mothers or in age-matched controls. Moreover, HIV+ mothers have significantly higher serum concentrations than HIV- mothers or an age-matched control group. These results suggest that s-HLA does not cross the placental barrier.  相似文献   
56.
A new immunochromatographic rapid test (Rapid Check HIV 1 and 2; Núcleo de Doen?as Infecciosas) for the detection of antibodies to human immunodeficiency virus type 1 and type 2 in human samples (whole blood, serum, and plasma) was evaluated and compared to the commercially available Determine (Abbott Laboratories). When whole-blood samples were evaluated, the specificity and sensitivity of both tests were 100%. However, when plasma samples were used, sensitivity for the Rapid Check HIV 1&2 and the Determine tests were 100 and 98.58%, respectively. The observed specificity for plasma samples was 98.94% for the Rapid Check HIV 1&2 and 96.97% for the Determine test. The results presented here are encouraging and support the adoption of both tests as an alternative to enzyme-lined immunosorbent assay and/or Western blots in regions where laboratorial infrastructure is not available or for use in the management of occupational accidents for healthcare workers.  相似文献   
57.
Accurate diagnosis of oral hairy leukoplakia (OHL) is important because it may be an early indicator of undiagnosed HIV infection; moreover, it may be a prognostic indicator. Our purpose was to investigate the histopathologic features of subclinical OHL and to evaluate and support the rationale of detecting subclinical OHL with cytopathology. The Epstein-Barr virus (EBV) was detected by immunohistochemistry and in situ hybridization in 4 cases of macroscopically normal lateral borders of tongue mucosa from 8 AIDS necropsies and in none of 8 controls. The histopathologic features were specific when based on nuclear changes: Cowdry type A inclusion, ground glass, and nuclear beading. Smears were obtained from 50 patients with AIDS, without OHL, from the scraping of lateral borders of the tongue. Numerous clusters of the cells were associated with Candida organisms (30% of cases). Nuclear changes were observed in 12 patients (24%) on both sides of the tongue. We describe the histopathologic features of subclinical OHL, and our observations suggest that cytopathology can detect OHL in the subclinical phase.  相似文献   
58.
The human wild-type (wt) p53.264-272 peptide is a universal tumor antigen and recognized by HLA-A*0201 (A2.1)-restricted CTL. Generation of this epitope by constitutive 20S proteasomes is prevented by a p53 R to H hotspot mutation at the C-terminal flanking residue 273. We report on the impact of the interferon-gamma (IFN-gamma)-inducible proteasomal activator PA28 (11S regulator) and the immunoproteasome on the in vitro and cellular processing of wt and mutant (mut) p53 substrates. We found that production of the antigenic 264-272 peptide from wt p53 by constitutive as well as immunoproteasomes is accelerated and amplified by the PA28 activator. PA28 and (immuno)proteasomes were not capable to reconvert the resistance of epitope release from mut p53. Maximum and accelerated antigen production in vitro and on the cellular level required the IFN-gamma-inducible interaction of immunoproteasomes and PA28. We conclude that efficient processing of p53.264272 from wt p53 is governed by the proteasome/PA28 complex. These studies have important implications for p53-specific cancer immunotherapy and demonstrate that the effects of the immunoproteasome and PA28 are influenced by the individual epitope and its flanking sequence context.  相似文献   
59.
Mitochondrial DNA (mtDNA) large deletions and mtDNA mutations have been demonstrated in various types of human cancer. The relationship between the occurrence of such alterations and the nuclear microsatellite instability (MSI) status of the neoplastic cells remains controversial. In an attempt to clarify the situation in gastric carcinoma, we studied, by PCR/SSCP and sequencing, five mitochondrial genes and two D-loop regions in 32 gastric carcinomas that had been previously screened for MSI and mitochondrial common deletion. MtDNA alterations were detected in 26 carcinomas (81%). All the mtDNA mutations, which occurred mainly in the D-loop and ND1 and ND5 genes, were transitions. D-loop alterations (insertions and/or deletions) were not significantly associated with mutations in the coding regions. There was a trend towards an inverse relationship between the occurrence of mitochondrial common deletion and mtDNA mutations. No significant relationship was observed between MSI status and mtDNA mutations, whereas the mitochondrial common deletion appeared to be almost exclusively restricted to MSI-negative tumors. The latter finding--almost no gastric carcinoma with MSI-positive phenotype has large deletions of mtDNA--needs to be confirmed in a larger series and in tumors from other organs.  相似文献   
60.
Immunoglobulin levels were measured in serum samples from 36 patients with different clinical forms of chronic Chagas' disease. Increased IgA levels were observed in 50% of the patients in the chronic digestive group and there was a significant correlation with the severity of the disease. IgG and IgM levels were within the normal range. Anti-ssDNA antibodies and EVI (endothelium, vessels and interstitium) antibodies were found in some patients with different clinical forms of the disease.  相似文献   
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