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1.

Background  

The ability of medical residents training at U.S. urban medical centers to diagnose and manage tuberculosis cases has important public health implications. We assessed medical resident knowledge about tuberculosis diagnosis and early management based on American Thoracic Society guidelines.  相似文献   
2.
Contraception during perimenopause.   总被引:4,自引:0,他引:4  
Perimenopause marks the transition from normal ovulation to anovulation and ultimately to permanent loss of ovarian function. Fecundity, the average monthly probability of conception, declines by half as early as the mid-forties, however women during the perimenopause still need effective contraception. Issues arising at this period such as menstrual cycle abnormalities, vasomotor instability, the need for osteoporosis and cardiovascular disease prevention, as well as the increased risk of gynecological cancer, should be taken into consideration before the initiation of a specific method of contraception. Various contraceptive options may be offered to perimenopausal women, including oral contraceptives, tubal ligation, intrauterine devices, barrier methods, hormonal injectables and implants. Recently, new methods of contraception have been introduced presenting high efficacy rates and minor side-effects, such as the monthly injectable system, the contraceptive vaginal ring and the transdermal contraceptive system. However, these new methods have to be further tested in perimenopausal women, and more definite data are required to confirm their advantages as effective contraceptive alternatives in this specific age group. The use of the various contraceptive methods during perimenopause holds special benefits and risks that should be carefully balanced, after a thorough consultation and according to each woman's contraceptive needs.  相似文献   
3.
We report a case of trisomy 2 mosaicism detected upon amniocentesis in a woman with advanced maternal age. A mos 47,XY,+2(4)/46,XY(21) karyotype was revealed using standard GTG banding. There were no pathological sonographic findings and the fetal size was normal for gestational age at 16th week. The use of serial high-resolution ultrasound examination of the fetus to detect major abnormalities was offered as an option to the parents who, however, decided for termination of the pregnancy. Fetal autopsy did not reveal any malformations. Trisomy 2 mosaicism is associated with variable phenotypic abnormalities without a specific pattern, intrauterine growth restriction, fetal demise or stillbirth. The rarity of trisomy-2 mosaicism in prenatal diagnosis, as well as the increased risk of an abnormal outcome makes the diagnostic approach and genetic counseling difficult.  相似文献   
4.
Fetal trophoblasts can be found in maternal circulation from an early stage of pregnancy and thus provide a potential source of DNA for non-invasive prenatal diagnosis. We have developed a two-step method for trophoblast isolation between the 8th and 12th week of pregnancy. Blood was sampled from 14 women undergoing termination of pregnancy or spontaneous abortion. Immunomagnetic beads precoated with HLA class I and II, and with anti-cytokeratin-18 monoclonal antibodies, were used to remove CD8+ and other maternal cells, and to select for fetal trophoblasts, respectively. Microsatellite analysis was performed on DNA extracted from the isolated, maternal, paternal and placental cells after PCR amplification. Recovery of the trophoblasts was confirmed in 13/14 cases (93%) by the identification of an identical microsatellite pattern for fetal and placental cells. Further evidence was the presence of heterozygous alleles of both maternal and paternal origin. The correct prediction of gender in all five male fetuses was an additional confirmation of trophoblast recovery. We conclude that trophoblasts can be effectively isolated from maternal blood in the first trimester, and by using polymorphic microsatellite markers to confirm sample purity, this method has potential future application in prenatal diagnosis.  相似文献   
5.
Data are presented from the Baltimore Young Men’s Survey, a cross-sectional, venue-based sample survey of risks associated with HIV and report of a prior HIV test, conducted between 1996 and 2000, and enrolling 843 young men who have sex with men (MSM) aged 15–29 years. HIV prevalence was 12.1% overall and racial disparities in HIV prevalence were pronounced (range, 2.9% among non-Hispanic whites to 27.1% among non-Hispanic blacks). Risks independently associated with being HIV-positive were: being between 26 and 29 years of age, being non-Hispanic black or of other/mixed race, having had 20 or more lifetime male sex partners, having been diagnosed with a sexually transmitted disease (STD), and not being currently enrolled in school. The majority of participants (78.9%) reported a prior HIV test. In multivariate analysis, being older, having had five or more lifetime male sex partners, having had anal intercourse with males, reporting an STD diagnosis, and reporting recent unprotected anal sex were associated with report of a prior HIV test. Prevention efforts must address high HIV prevalence among young non-Hispanic black MSM and must make testing and effective counseling for young MSM readily available.  相似文献   
6.
Interest in estimating HIV-1 incidence using specimens obtained as part of cross-sectional surveys has led to the development of new methods to detect recent HIV-1 infection through the testing of a single anti-HIV-positive specimen. These assays are based on quantitative and qualitative differences in anti-HIV-1 antibodies between recent and long-standing infections. An ongoing vaccine preparedness study enrolled female sex workers in the Dominican Republic. Specimens from women found to be HIV positive at baseline were tested for recent HIV-1 infection using the detuned assay, avidity index, and BED-CEIA assay. An unweighted kappa statistic in pairwise comparisons was used to estimate the correlation of recent HIV-1 infection detection by the three methods. Nineteen (3.9%) of 482 women were positive for HIV-1 infection. The incidence of HIV infection was 1.4% [95% confidence interval (CI): 0.2, 5.3], 0.9%(95% CI: 0.1, 4.4), and 1.0%(95% CI: 0.1, 4.4) using detuned assay, avidity index, and BED-CEIA techniques, respectively. The overall agreement between both detuned assay and avidity index and detuned assay and BED-CEIA was 94%(kappa = 0.8, 95% CI; 0.3, 1.0). The correlation was highest between BED-CEIA and avidity index methods (100%; kappa = 1.0). All three methods performed similarly in detecting recent HIV-1 infection in this region dominated by clade B HIV-1 infection. Although incidence estimates were slightly higher using the detuned assay method, they were not significantly different. These assays may be of value in both clinical research and practice. The utility of individual assays for recent infection detection will depend upon operating characteristics, HIV-1 subtype limitations, and selection of appropriate assay cutoff values.  相似文献   
7.
Molecular genotyping has been used to characterize Toxoplasma gondii strains into the three clonal lineages known as types I, II, and III. To characterize T. gondii strains from Greece and Cyprus, polymerase chain reaction-restriction fragment length polymorphism analysis on the GRA6 gene was performed directly on 20 clinical samples from 18 humans (11 pregnant women, six patients with lymphadenopathy, and one patient positive for human immunodeficiency virus) and two rats. Characterization of T. gondii types was performed after digestion of amplified products with Mse I. The 20 strains were characterized as type II (20%) and type III (80%). Of these strains, 19 originated from the island of Crete (4 strains type II and 15 strains type III), and 1 from the island of Cyprus (type III). Although both type II and type III strains were found, type III was the most prevalent in Crete.  相似文献   
8.
9.
OBJECTIVE: To present the clinical application of the multispectral imaging colposcopic system (MIS colposcopy). METHODS: MIS colposcopy was performed on 123 enrolled women. After a 3% acetic acid application, sequential images were captured, analyzed, and stored automatically. Directed biopsies were taken from distinct marked acetic acid-responsive tissue areas indicated on the monitor, while a real-time assessment of the curves of intensity of the backscattered light (IBSL) vs. time was performed. Blind biopsies were taken from non-acetowhitening areas. Histological findings were correlated with MIS colposcopy results and compared with conventional colposcopy and Pap test results. RESULTS: Acetic acid-tissue interaction resulted in temporal and spatial alterations to the light scattering properties of the abnormal tissue that was analyzed. The shape of IBSL curve and the "relaxation time" (the time it takes for IBSL to decay to 1/e of its peak value) changed in accordance with the underlying lesion. More severe CIN lesions lead to higher maximum IBSL; longer durations of acetowhitening lead to increasingly delayed exponential decay of IBSL curve. To compare with histological examination, MIS colposcopy had a 1.7% false-diagnostic rate, while PAP test and conventional colposcopy had 24.4% and 22% false-diagnostic rates, respectively. A triple exponential function created a "pseudocolor" image that comprised the grade map of the lesion, and this is frequently representative of the duration/degree of the induced alterations. CONCLUSION: Improved diagnostic information can be gained by recording the optical information in a narrow spectral range with high spatial resolution. MIS colposcopy can be used in the diagnosis of uterine cervix pathological conditions and in the differentiation between CIN lesions.  相似文献   
10.
We report a case of the 3C (cranio-cerebello-cardiac) syndrome, also known as Ritscher-Schinzel syndrome, a rare autosomal recessive disorder characterized by craniofacial, cerebellar, and cardiac anomalies. In addition to features previously reported the child had Wormian bones of the skull, intra-abdominal testes, and posterior embryotoxon that have not previously been reported as part of the 3C syndrome.  相似文献   
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