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951.
952.
Rapid orthodontic extrusion is indicated for cases involving biological space invasion of the periodontal ligament in which the surgical increase of the clinical crown can compromise esthetics or the support of the adjacent teeth. This article presents the case report of a tooth with radicular perforation 1.0 mm below the bone crest. A procedure to restore the biological distances was necessary. Rapid orthodontic extrusion of the affected tooth, with anchorage in the adjacent osseointegrated implants, was selected. 相似文献
953.
The polymerase chain reaction (PCR) has been the most promising test for HIV-1 early diagnosis in infants suspected of perinatal transmission. The first and second reactions of the amplification in 41 infants (under 18 months old) suspected of HIV-1 perinatal infection, were standardized and carried out in the present study. The first and the second PCR were carried out with the sets of primers JA4-JA7, JA9-JA12, JA13-JA16, and JA17-JA20 for the first reaction of amplification (outer primers) and JA5-JA6, JA10-JA11, JA14-JA15, and JA18-JA19 for the second reaction of amplification (inner primers), resulting in amplification of 131, 341, 172, and 129 pb, respectively. From 41 patients analysed, 12 patients presented positive to HIV-1 infection by PCR. The gag, env (region 1), and pol regions presented a greater sensitivity. The first and the second reactions of the amplification were performed with the same concentration of MgCl2 for all sets of primers. The results agree with several studies that affirm that the PCR is the indicated method for HIV-1 early diagnosis in infants suspected of perinatal infection. 相似文献
954.
Galão AO Pinheiro da Costa BE d'Avila DO Poli de Figueiredo CE 《American journal of obstetrics and gynecology》2004,191(2):572-575
OBJECTIVE: This study was undertaken to evaluate erythrocyte membrane transport of L-arginine in pregnancy and immediately postpartum. STUDY DESIGN: The study comprised 103 women with normal pregnancy, initially evaluated at the second trimester (II), followed into the third trimester (III), and immediately postpartum (PP). Total erythrocyte L-arginine uptake was measured with (14)C-L-arginine, at 37 degrees C, for 3 minutes. The maximal transport capacity (V(max)) and half-saturation constant (K(m)) were obtained with the use of Michaelis-Menten kinetics. Results are expressed as mean+/-SD. Analysis of variance, followed by Tukey test, was used in statistical analysis (alpha< or =.05). RESULTS: V(max) (micromol/L cells per hour) progressively increased at each consecutive time period: 779+/-283, 946+/-289, and 1349+/-390, at II, III, and PP, respectively (P<.001). Similarly, K(m) (micromol/L) values increased from 56+/-20 at time II, to 62+/-18 at time III, and 69+/-24 at PP (P<.001). CONCLUSION: Total erythrocyte L-arginine uptake (V(max) and K(m)) increases progressively along normal pregnancy, with a further increase immediately postpartum. 相似文献
955.
Angiotensin-converting enzyme gene polymorphism in preeclampsia and normal pregnancy 总被引:5,自引:0,他引:5
Galão AO de Souza LH da Costa BE Scheibe RM Poli de Figueiredo CE 《American journal of obstetrics and gynecology》2004,191(3):821-824
OBJECTIVE: The purpose of this study was to evaluate the angiotensin-converting enzyme gene polymorphism in pregnant women with and without preeclampsia. STUDY DESIGN: Preeclampsia was defined as hypertension and pathologic proteinuria in pregnant women after gestational week 20. Genomic DNA was isolated from leukocytes. The insertion-deletion polymorphism in intron 16 of the angiotensin-converting enzyme gene was detected in DNA samples with the use of the polymerase chain reaction. Chi-squared and Student t tests were used for statistical analysis. RESULTS: In preeclampsia (n=51 women) angiotensin-converting enzyme genotypes were deletion-D (DD) in 16 women (31%), insertion-I (II) in 12 women (24%), and insertion-deletion in 23 women (45%); in the control group (n=71), the angiotensin-converting enzyme genotypes were DD in 21 women (30%), II in 17 women (24%), and insertion-deletion in 33 women (46%). Angiotensin-converting enzyme genotype distribution and allelic frequencies were not different between groups. CONCLUSION: No difference in the angiotensin-converting enzyme genotype distribution was found between preeclampsia and normal pregnancy. The results showed no association between angiotensin-converting enzyme polymorphism and the development of preeclampsia. 相似文献
956.
da Costa BP Steibel JP Antonello IC Guimarães JA Poli de Figueiredo CE 《American journal of obstetrics and gynecology》2004,190(2):468-471
OBJECTIVE: Uptake of L-arginine by the cell via amino acid transporter systems is the first step for nitric oxide (NO) production. The current study aimed to assess the total L-arginine uptake in erythrocytes of normal pregnant and preeclamptic women. STUDY DESIGN: Twenty-one normal pregnant and 21 preeclamptic women were studied. To measure total L-arginine uptake in erythrocytes, carbon 14 was used as a marker and Michaelis-Menten kinetic parameters (V(max) and K(m)) were evaluated. RESULTS: In preeclamptic women, there was a significant increase (P<.004) in the mean maximal capacity of transport in erythrocytes (V(max)=982.69 micromol/L cells/h+/-433.51) in comparison with normal pregnant women (V(max)=584.73 micromol/L cells/h+/-422.33). No significant difference was detected in the half-saturation constant (P=0.978). CONCLUSION: The transport kinetics of the NO precursor, L-arginine, is altered in erythrocytes of preeclamptic women. It is possible that abnormal L-arginine uptake may contribute to the pathophysiologic mechanisms of preeclampsia syndrome. 相似文献
957.
Branca M Costa S Mariani L Sesti F Agarossi A di Carlo A Galati M Benedetto A Ciotti M Giorgi C Criscuolo A Valieri M Favalli C Paba P Santini D Piccione E Alderisio M De Nuzzo M di Bonito L Syrjänen K 《European journal of gynaecological oncology》2004,25(6):689-698
OBJECTIVES: In women with HIV-associated immunosuppression, HPV infections have an increased risk of progression to high-grade cervical intraepithelial neoplasia (CIN). With the HAART-induced prolonged survival and more protracted clinical course of AIDS, progression of CIN to cervical cancer (CC) has become a clinically relevant issue, and the mechanisms responsible for HIV-HPV interactions need further elucidation. The study design and analysis of the baseline data of our new project are presented. MATERIAL AND METHODS: This project is a combination of a prospective cohort study of HIV- and HIV+ women, and a retrospective analysis of CIN lesions and cervical cancer. Up to the present, 244 women have been enrolled (17 HIV+) and subjected to epidemiological interview, colposcopic examination, sampling for HPV testing and typing (PCR, InnoLiPA), and HPV serology. The retrospective series of biopsies were analysed for 13 biomarkers (monitoring key molecular events) using immunohistochemistry and tested for HPV by PCR and TaqMan. RESULTS: HIV- and HIV+ women differ in their exposure status to many of the key epidemiological risk factors of cervical cancer, the most significant ones being number of sexual partners (p = 0.0001), age at onset of sexual activity (p = 0.002), and contraception (yes-no) (p = 0.009). The differences in the baseline clinical observations are less dramatic; HIV-positive women had more frequent HSIL PAP tests (p = 0.040), CIN2 or higher in cervical biopsy (p = 0.049), and external genital warts (p = 0.019). The factors predicting intermediate endpoint markers of cervical cancer, i.e., HSIL PAP smear, ATZ2 in colposcopy, and high-grade CIN in biopsy were analysed in univariate and multivariate regression models. All factors significant in univariate analysis were entered in the multivariate model; HIV-status and Pap smear history maintained their independent predictive power of the HSIL Pap test. The most powerful predictor of ATZ2 colposcopy was HSIL in Pap test. Only the HSIL Pap test and ATZ2 colposcopy remained significant independent predictors of high-grade CIN (p = 0.0001 and p = 0.008, respectively) in the multivariate model. CONCLUSIONS: The three intermediate endpoint markers are closely interrelated, but predicted in part by different covariantes in the causal pathway to cervical cancer. To elucidate whether the increased risk of HIV-positive women to high-grade CIN is due a) to their different exposure status to the risk factors, b) to the direct effects of HIV, or c) to molecular interactions between HIV and HPV, we need to complete these analyses separately in HIV+ and HIV- women. 相似文献
958.
Sales AM Sabroza PC da Costa Nery JA Duppre NC Sarno EN 《International journal of leprosy and other mycobacterial diseases : official organ of the International Leprosy Association》2004,72(3):320-323
A comparative study was made of the initial and final bacterial indices (BIs) of 213 MB leprosy patients who had been administered 12-dose (Group 1/128 patients) and 24-dose (Group 2/85 patients) World Health Organization multi-drug therapy to measure the effectiveness of both treatment regimens. All patients were evaluated at the beginning of treatment, at 12 months, and again after 24 months had elapsed. Decline in BI values and average BIs at 24 months were found to be similar for both groups. Moreover, no statistical difference between the two treatment regimens was found in the frequency rate of reaction. 相似文献
959.
Ratto GB Costa R Vassallo G Alloisio A Maineri P Bruzzi P 《The Annals of thoracic surgery》2004,78(1):234-237
Background
We retrospectively reviewed our 12-year experience in the surgical treatment of non-small cell lung cancer invading the left atrium. End points of the study were overall survival and factors potentially affecting survival.Methods
Nineteen consecutive patients with lung cancer invading the left atrium underwent surgery. Three patients with N2 disease underwent induction chemotherapy. Patients with either incomplete resections or pN2 disease received postoperative chemoradiotherapy.Results
Five-year survival was 14%, and the median survival time was 25 months. These figures refer to a very homogeneous group of patients with respect to the extent of atrial infiltration. Patients with N2 disease tended to have a worse outcome than patients with N0 or N1 disease (p = 0.06). The 3 patients with N2 disease who underwent induction chemotherapy were alive and disease-free at 30, 15, and 11 months from surgery. Survival was not affected by histology, type of surgery, or completeness of resection. Three patients with residual cancer in the atrial resection margin underwent postoperative chemoradiotherapy and are alive at 25, 17, and 15 months after surgery.Conclusions
In spite of the poor survival rates we report, the present experience suggests that more-favorable results could be expected by the routine preoperative use of positron emission tomographic scan staging, a more-extensive assessment of atrial invasion, the application of induction chemotherapy in patients with N2 disease, and postoperative chemoradiotherapy in patients with tumors abutting the atrial resection margin. 相似文献960.