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91.
ObjectiveTo evaluate the diagnostic accuracy of measuring cervical length (CL) in combination with cervical and plasma nitric oxide metabolite (NOx) levels to identify women undergoing preterm labor (PTL) who will deliver preterm.MethodsA hospital-based prospective cohort study of 730 women undergoing spontaneous PTL between 24 and 33 weeks + 6 days of pregnancy was conducted. Measurement of cervical and plasma NOx levels and ultrasonographic assessment of CL were performed to find the best model to predict preterm delivery (PTD). Optimal cut-off values were calculated by receiver operating characteristic (ROC) curve analysis. Logistic regression analysis and rank correlation tests were also performed.ResultsCL of 15 mm or less, cervical NOx levels greater than 87.6 μmol/L, and plasma NOx levels greater than 123 μmol/L (P < 0.0001) were the only factors significantly associated with PTD within 7 days of sampling. This combined model provided high diagnostic accuracy (sensitivity 80.0%; specificity 99.2%). Both cervical and plasma NOx levels were negatively correlated with CL (r = ? 0.453, P < 0.0001 and r = ? 0.362, P < 0.0001, respectively).ConclusionCombined measurement of CL and levels of cervical and plasma NOx could help identify women undergoing symptomatic PTL who are at increased risk of PTD.  相似文献   
92.
OBJECTIVE: The aim of this study was to monitor the effect on viral DNA and RNA of early treatment with highly aggressive antiretroviral therapy (HAART), in comparison with zidovudine (ZDV) monotherapy or no treatment in subjects with primary HIV-1 infection (PHI). DESIGN AND METHODS: Of the 28 patients selected, four were untreated, four received ZDV alone, 10 received a triple combination (ZDV, lamivudine (3TC) and saquinavir (SQV)) and 10 received a quadruple combination (ZDV, 3TC, SQV and ritonavir (RTV)). Seroconversion was monitored by means of Western blot profile analysis. A quantitative polymerase chain reaction (PCR) assay in the HIV gag region was used to monitor viral DNA and the nucleic acid sequence based amplification (NASBA) system for viraemia (HIV-RNA). RESULTS: There was a certain level of heterogeneity in the baseline values of HIV-DNA and RNA. Early HAART led to a rapid recovery in the number of CD4 cells and the CD4/CD8 cell ratio and a reduction in HIV-RNA to undetectable levels, which was significantly greater than in the untreated patients or those treated with ZDV. Although a reduction in DNA levels was also observed in the HAART-treated subjects, this variation was not significant. CONCLUSIONS: The parameters of viral replication and CD4 cell recovery were only slightly better in the patients receiving ZDV monotherapy than in the untreated patients, thus confirming that the course of the infection is hardly affected by the monotherapy. The early introduction of HAART greatly reduces plasma viraemia and restores the number of CD4 cells for up to 1 year. HIV-DNA remains detectable, although at low levels, thus confirming that the early established reservoir of infected cells is little affected. Longer periods of observation and the introduction of complementary approaches, such as immunomodulatory therapies, will provide further information concerning the possibility of radically interfering with the natural evolution of the disease.  相似文献   
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Squamous cell carcinoma (SCC) of the lip is a relatively common malignancy of the head and neck region. Tumour thickness, grading and perineural invasion are significant prognostic indicators. However, there is still the need of new reliable biological markers able to predict the prognosis of the single cases with an unfavourable biological behaviour unpredictable by the classic clinical-pathological parameters. 32 cases of (SCC) of the lower lip were analysed for their clincopathologic features, and immunohistochemical expression of Fas/FasL in neoplastic cells and in inflammatory infiltrate. Moreover the density and phenotype of tumour-infiltrating lymphocytes (TIL) were analysed. The results were related with the follow-up of the patients ranging from 2 to 6 years. The cases with over-expression of Fas/FasL in neoplastic cells and Fas+ in T cells preferentially showed a more aggressive clinical behaviour (P<0.01). Moreover we found an alteration of the normal expression of CD4 and CD8 lymphocyte types in ten cases. This data suggest that the Fas/FasL pathway is involved in the close relation between neoplastic cells and T cells and so in the biological behaviour of these tumours.  相似文献   
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p63 belongs to a protein family that includes 2 structurally related proteins, p53 and p73. The aim of this study was to investigate the biologic role of p63 in oral tumorigenesis and its possible role as prognostic marker in oral cancer. Ninety-four cases of oral squamous cell carcinoma and 10 cases of normal mucosa were analyzed for p63 expression by immunohistochemistry. Normal oral mucosa showed a basal and parabasal expression of p63. Five (5.3%) cases of oral cancer showed less than 10% of positive tumor cells; in 33 (35.1%) cases the positive tumor cells comprised between 10% and less than 30%, in 36 (38.3%) cases the positive tumor cells comprised between 30% and less than 50%, and in 20 (21.3%) cases the positive tumor cells were more than 50%. There was also a statistically significant correlation between p63 expression and tumor differentiation: p63 expression was amplified in poorly differentiated tumors (P < .05). When analyzed for prognostic significance, patients with perineural infiltration had poorer survival rates than the group with no perineural infiltration (P < .05) and patients with increased p63 expression had poorer survival rates than the group with reduced p63 expression (P < .05). The statistical analysis showed no significant correlation between p63 expression, sex, age, tumor size, staging, recurrence, and metastasis. Cases with diffuse p63 expression were more aggressive and poorly differentiated and related to a poorer prognosis. These data suggest that p63 expression may be useful to identify cases of oral squamous cell carcinoma with more aggressive and invasive phenotype providing novel diagnostic and prognostic information on individual patient survival with oral cancers.  相似文献   
98.
The detection of HIV-1 proviral DMA in children born to seropositive mothers was studied using the polymerase chain reaction with either a radioactive electrophoretic method or a novel procedure that employs colorimetric microwell visualization. Peripheral blood mononuclear cell lysates from 18 HIV-1 infected children and 28 uninfected subjects were assayed for a 142 bp fragment of DNA from the gag region of HIV-1 using the primer pair SK145-431. Detection of amplified DNA was carried out by hybridization with a radiolabeled SK102 probe, or with a tagged SK102 probe permitting colorimetric detection. The radioactive detection procedure demonstrated 100% specificity and correlated with the serological results. The assay was more sensitive than the p24 antigen test, but two false negative results were obtained. One was from a sample taken at 2 weeks, an age at which unde-tectable provirus levels were reported in almost all HIV-1 infected newborns. The second was probably due to a low copy number of proviral DNA, as positive results were obtained in all other (6) samples from this child. Comparative analysis in a limited number of specimens of radioactive and colorimetric detection following PCR revealed 100% specificity and comparable sensitivity with 4 discordant results. The results show that PCR is the best method for early diagnosis of HIV-1 infection in pediatric subjects. The study also demonstrated the value of a colorimetric detection method for PCR products. This colorimetric microwell plate procedure may prove a useful technique in routine diagnosis of HIV-1 infection in children. © 1994 Wiley-Liss, Inc.  相似文献   
99.
Periodontitis is the commonest bacterial disease of humans and is the major cause of adult tooth loss. About half of the oral microflora is unculturable; and 16S rRNA PCR, cloning, and sequencing techniques have demonstrated the high level of species richness of the oral microflora. In the present study, a PCR primer set specific for the genera Porphyromonas and Tannerella was designed and used to analyze the bacterial populations in subgingival plaque samples from inflamed shallow and deep sites in subjects with periodontitis and shallow sites in age- and sex-matched controls. A total of 308 clones were sequenced and found to belong to one of six Porphyromonas or Tannerella species or phylotypes, one of which, Porphyromonas P3, was novel. Tannerella forsythensis was found in significantly higher proportions in patients than in controls. Porphyromonas catoniae and Tannerella phylotype BU063 appeared to be associated with shallow sites. Targeted culture-independent molecular ecology studies have a valuable role to play in the identification of bacterial targets for further investigations of the pathogenesis of bacterial infections.  相似文献   
100.
In the present work we show that during the degenerative process occurring after the cryo-elimination of the tench peripheral growing zone many non-neuronal cell types in addition to the resident microglial cells, appear within the affected areas. Some of them are normally found in the retina, such as the retinal pigmented epithelium cells and others originate from extra-retinal tissues. We identified these as granular leukocytes and macrophages. The microglial cells and macrophages, those resident in the sub-retinal space, and the invasive ones, act as phagocytes. The analysis of the injured retina following lesion shows that the invasive macrophages, arising from the scleral extra-retinal tissues, penetrate the neural retina, and migrate from the scleral to the vitreal portion. In contrast those coming from the vitreal extra-retinal tissues migrate in the opposite direction. Moreover, the retinal pigmented epithelium cells present remarkable modifications in their morphology and distribution and enter the neural retina, where they disrupt the surrounding tissue. We have also observed that this cryo-lesion causes an inflammation mediated by a type of granular leukocyte, denominated heterophils which penetrate the neural retina and probably come from the blood supply. Our results suggest that, during the first days after the lesion, the participation of diverse non-neuronal cells removing cell debris from the damaged zone should create a favourable environment allowing the regeneration of the neural retina.  相似文献   
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