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51.
To date, human adenoviruses are classified into 53 types (types 1–51 and types 53 and 54), which have been grouped into six species named A through F, and the recently identified type 52 has been proposed as member of a new species, G. Type classification is based on type-specific epitopes within loop 1 (L1) and loop 2 (L2) of the hexon protein, which contain seven hypervariable regions that are responsible for type specificity. In this paper, we present the characterization of an adenovirus strain isolated from a male AIDS patient in Cordoba, Argentina. This strain was found to be a member of species D by genomic Sma I restriction analysis. Sequencing of the L1 and L2 regions of the hexon gene and immunological characterization by virus neutralization revealed this hexon to be unique and distinct from the previously identified hexons of types within species D. A seroepidemiologic study in the human population of Cordoba showed that this strain was not endemic in the local human population.  相似文献   
52.
53.
BACKGROUND: Many patients with advanced non-small-cell lung cancer (NSCLC) do not tolerate cisplatin-based regimens because of its nonhemathological toxicity. PATIENTS AND METHODS: We evaluated the response rate safety of new platinum analogue regimens, randomizing 147 patients with nonoperable IIIB/IV NSCLC to (i) carboplatin (area under the curve = 5 mg min/ml) on day 1 plus gemcitabine (GEM) (1000 mg/m(2)) on days 1 and 8 for six cycles; (ii) same regimen for three cycles followed by docetaxel (Taxotere) (40 mg/m(2)) on days 1 and 8 plus GEM (1250 mg/m(2)) on days 1 and 8 for three cycles; (iii) oxaliplatin (130 mg/m(2)) on day 1 plus GEM (1250 mg/m(2)) on days 1 and 8 for six cycles. RESULTS: Intention-to-treat objective response rates were 25%, 25% and 30.6% in arms A, B and C, respectively. Median survival was 11.9, 9.2 and 11.3 months in arms A, B and C, respectively. Grade 3/4 neutropenia/anemia occurred in 29%/12.5%, 10%/16.5% and 8%/6% of arms A, B and C, respectively; grade 3/4 thrombocytopenia in 20.5%, 16.5% and 6%; grade 1/2 neurological toxicity in 43% of arm C. CONCLUSIONS: Oxaliplatin/GEM (arm C) had similar activity to carboplatin/GEM (arm A), but milder hematological toxicity and may be worth testing in a phase III study against carboplatin/GEM in patients not suitable for cisplatin. The sequential regimen gave no additional benefit.  相似文献   
54.
The purpose of this study was to examine the effect of glass fibre reinforcement on the dimensional changes and water sorption of a heat-polymerising denture acrylic polymer and a microwave-polymerising denture acrylic polymer. Fifteen specimens from each group were prepared with 2% by weight (18 mg) E-glass fibre and 15 without glass fibre. The dimensional change measurements were made at three different stages on the 60 specimens. The water sorption calculations were made on specimens immersed in distilled water at 37 degrees C +/- 1 degree C for 0, 1 and 7 days. Glass fibre reinforcement and processing method do not affect the dimensional change of test specimens, but as the time increased the dimensional change decreased. The glass fibre reinforcement decreased water sorption, but the two processing methods failed to show a significant difference.  相似文献   
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56.
PURPOSE: We assessed how varicocelectomy alters semen quality in a large cohort of infertile men and determined whether it can change patient candidacy for assisted reproductive technology procedures. MATERIALS AND METHODS: A cohort of 540 infertile men with clinical palpable varicocele underwent microsurgical varicocelectomy and were followed more than 1 and 2 years postoperatively for alterations in semen quality and conception, respectively. Preoperatively and postoperatively the total motile sperm count was calculated in all semen analyses. Based on total motile sperm count values patients were divided into 4 groups according to the type of assisted reproductive technology for which they qualified, including 0 to 1.5 million or less (intracytoplasmic sperm injection candidates), 1.5 to 5 million or less (in vitro fertilization candidates), 5 to less than 20 million (intrauterine insemination candidates) and 20 million or greater sperm (spontaneous pregnancy candidates). Preoperative and postoperative semen quality was compared among individuals in these cohorts to determine the shifts in assisted reproductive technology care that are possible after varicolectomy. RESULTS: Mean patient age was 29.5 years (range 18 to 58). Microsurgical varicocelectomy was bilateral in 393 patients (73%), on the left side in 146 (27%) and on the right side in 1 (0.2%). A positive response to varicocelectomy, defined as a greater than 50% increase in total motile sperm count, was observed in 271 patients (50%). An overall spontaneous pregnancy rate of 36.6% was achieved after varicocelectomy with a mean time to conception of 7 months (range 1 to 19). Of preoperative in vitro fertilization and intracytoplasmic sperm injection candidates 31% became intrauterine insemination or spontaneous pregnancy candidates after varicolectomy. Of intrauterine insemination candidates 42% gained the potential for spontaneous pregnancy. CONCLUSIONS: Varicocelectomy has significant potential not only to obviate the need for assisted reproductive technology, but also to down stage or shift the level of assisted reproductive technology needed to bypass male factor infertility.  相似文献   
57.
Diffuse leiomyomatosis of the uterus: a case report with clonality analysis   总被引:5,自引:0,他引:5  
Diffuse uterine leiomyomatosis is a rare condition distinguished from the common uterine leiomyomata by involvement of the entire myometrium by innumerable, ill-defined, often small and confluent, histologically benign smooth-muscle nodules. Fourteen cases have been previously described in the literature. We report a case of diffuse leiomyomatosis in a 39-year-old woman. Several microscopic foci of the process were microdissected for clonality analysis. All samples showed a non-random X-chromosome inactivation pattern, and thus were consistent with a monoclonal neoplastic population of cells. However, in different foci of tumor, different X chromosomes were inactivated, supporting the independent origin of neoplastic clones and rejecting the possibility of a single clonal origin of all tumor cells. The results of the molecular analysis suggest that diffuse uterine leiomyomatosis may be an exuberant example of diffuse and uniform involvement of the entire myometrium by multiple leiomyomata. HUM PATHOL 31:1429-1432.  相似文献   
58.
59.
This study focused on clinical, hematological, and molecular aspects of sickle cell anemia pediatric patients from two different cites in Brazil. Seventy-one patients from S?o Paulo and Salvador, aged 3 to 18 years, were evaluated. Hematological analyses, betaS globin gene haplotypes, and alpha2 3.7kb-thalassemia were performed. Numbers of hospitalizations due to vaso-occlusive crises, infections, stroke, and cholelithiasis were investigated. S?o Paulo had more hospitalizations from vaso-occlusion, cholelithiasis, and stroke than Salvador. The Ben/CAR genotype predominated in both cities. Alpha2 3.7kb-thalassemia had a frequency of 28.2% in Salvador, mostly with Ben/CAR genotype (45.0%), while S?o Paulo had 22.5% with similar frequencies of the Ben/ CAR and CAR/CAR genotypes. Sickle cell anemia patients from S?o Paulo also had more episodes of stroke, which was observed among CAR/CAR, atypical, and BEN/CAR haplotypes. In Salvador stroke was only observed in the Ben/CAR genotype. Cholelithiasis had similar frequencies in the two cities. These data suggest a milder phenotype among patients in Salvador, possibly due to genetic, environmental, and socioeconomic factors. Further studies are needed to elucidate modulating factors and phenotype association.  相似文献   
60.
This work investigated the adsorption of autoantibodies such as anti-SS-A/Ro, anti-SS-B/La, anti-Sm, and anti-dsDNA on protein L-agarose gel. In order to determine better conditions for IgG adsorption on this matrix, some buffer systems were tested. Adsorption data were analyzed using the Langmuir and Langmuir-Freundlich isotherm models. The experimental isotherms were best described by the Langmuir-Freundlich model, which indicated negative and positive cooperativities for binding in the presence of PBS and HEPES buffers, respectively. The K(d) values for phosphate buffered saline solution (PBS) and hydroxyethylpiperazine ethanesulfonic acid (HEPES) were 2.8 x 10(-7) M and 3.2 x 10(-7) M, respectively, which indicate a high affinity between IgG and the immobilized protein L. The amount of protein adsorbed per amount of protein loaded was high for anti-Sm (44%) and anti-dsDNA (46%), but low for anti-SS-B/La (9%). The amount of albumin adsorbed was lower than 0.06 mg/mL, which may remove the need for a plasma replacement solution in clinical apheresis.  相似文献   
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