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Complex segregation analysis was applied to a sample of 107 Italian families with probands with obsessive compulsive disorder (OCD), using regressive logistic models to test for possible models of genetic transmission. We used two different phenotypic definitions of affection: 1) OCD; and 2) OCD plus Tourette's syndrome/chronic motor tics (CMT). Because of the potential relationship between OCD, Tourette's syndrome (TS), and other tic disorders, we considered these diagnoses to be determined by the same liability in subsequent steps of the analysis. For the 107 OCD families, the best fit was a dominant model of transmission (with a higher penetrance for females). When the phenotype boundaries were widened (OCD + CMT + TS), an unrestricted model of transmission became the best fit. We concluded that additional data are needed to support the hypothesis that Tourette's syndrome and OCD share a common etiology: on the basis of clinical and epidemiological considerations, the OCD phenotype probably presents a higher level of heterogeneity than the TS phenotype, and it could be regulated through different etiologic pathways.  相似文献   
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In older healthy men, aerobic exercise capacity is related to postischemic flow-mediated dilation of the brachial artery (FMD), but corresponding data in a younger population is not available. In addition, whether submaximal aerobic exercise performance also correlates with this kind of vasomotor reactivity is not known. Therefore, in 15 nonsmoking young healthy men [age 27 (5) years; body mass index: 24 (2) kg/m2; mean (SD)] with different levels of ordinary physical activity, but not performing upper-extremity training, we measured FMD at 1 min after reactive hyperemia, and pulmonary oxygen uptake (O2) at ventilatory anaerobic threshold (O2AT) and at peak effort (peak O2) during an incremental exercise on a treadmill. In our participants, FMD was 9.1 (3.4)%, O2AT was 40.72 (5.92) ml/kg per min, and peak O2 was 52.95 (8.13) ml/kg per min. Using bivariate Pearsons correlation, and in separate multivariate regression analyses, O2AT and peak VO2 showed a significant and reasonably good correlation with FMD (r=0.84, P<0.001 and r=0.77, P=0.001, respectively), independent of age, body mass index and serum total cholesterol (=0.77, P<0.001, R2 of the overall model=0.79 and =0.70, P<0.005, R2 of the overall model=0.69, respectively). Our data provide evidence suggesting that in young healthy men a higher submaximal and maximal aerobic exercise performance is associated with a greater FMD of peripheral conduit arteries.  相似文献   
14.
A radioimmunoassay (RIA) for human thyroxine-binding prealbumin (PA) is described. It employs highly purified PA, anti-human PA serum at 1:30,000 final dilution, normal bovine serum as a carrier, and polyethyleneglycol to precipitate the immune complexes. This assay is extremely sensitive (limit of detection less than 0.2 micrograms per dL or less than 3.6 X 10(-15) moles per tube), accurate (recovery = 98.7 +/- 9 percent, mean +/- S.D.) and reproducible (intra- and inter-assay coefficients of variation = 3.6 to 6.3 percent and 7.2 to 9.5 percent, respectively). There was a highly significant correlation when the RIA was compared with radical immunodiffusion or with PA maximal binding capacity for thyroxine (r = 0.944 and r = 0.724, respectively, p less than 0.001). Concentration of PA in sera from normal subjects (age range = 20 to 88 years) averaged 27.7 +/- 0.5 mg per dL (mean +/- S.E.M.), with significantly higher values in males than in females in all age groups with the exception of the older subjects (20 to 50 years: males = 26.5 to 37 mg per dL; females = 23.1 to 33.8 mg per dL). Levels of PA progressively declined after the fifth decade of life. Pregnancy, hyperthyroidism, chronic liver diseases, cystic fibrosis, cancer and other non-thyroidal illnesses were associated with decreased levels of serum PA. Untreated hypothyroidism and chronic renal diseases showed widely scattered values of PA. Inherited thyroxine-binding globulin (TBG) abnormalities and bisalbuminemia had no apparent effect on concentrations of serum PA.  相似文献   
15.
BACKGROUND: Hymenoptera venom hypersensitivity is an epidemiologically important problem. The only effective treatment in the management of venom-allergic patients with a history of generalized reactions to insect sting is specific immunotherapy. OBJECTIVE: To demonstrate safety and effectiveness of a modified ultrarush desensitization protocol in venom-allergic patients. METHODS: Fifty-seven patients with Hymenoptera venom allergy underwent a specific 1-day ultrarush desensitization by the subcutaneous route, reaching the cumulative dose of 101.1 microg in 2.5 hours. The maintenance dose (100 microg) was administered after 15 days and thereafter once a month. Patients were followed up for a year. Antihistamines were withheld for 15 days before and during desensitization to not underestimate the incidence of adverse effects. RESULTS: All patients but I completed the ultrarush desensitization. (This patient discontinued the treatment because of a hypertensive crisis not related to the desensitization.) The treatment caused a rapid variation of immunological parameters (IgE, IgG4) since the 15th day. After the desensitization, skin prick test results became negative in 15 patients (27%, decrease of 3.5 log), whereas they decreased in 14 patients (25%, decrease of 1 log). Sixty-four percent showed no adverse effects. Only 7% had a mild systemic reaction. CONCLUSIONS: Ultrarush desensitization is an effective and safe therapy in the management of patients with Hymenoptera venom allergy. In fact, it provides a faster tolerance, without significant differences regarding incidence of severe adverse effects, compared with traditional and rush protocols. It can be adopted for all patients, even children and teenagers.  相似文献   
16.
The growth rate of a tumor cell population depends on two major factors: the percentage of proliferating cells (cell growth fraction) and the rapidity of their duplication (cell proliferation rate). The authors evaluated the prognostic and predictive value of both kinetics parameters in a large series of breast cancer patients (n=504). The cell growth fraction was determined by MIB-1 immunostaining, the cell proliferation rate by AgNOR analysis. Ki-67 LI (labeling index) and AgNOR area were significantly associated with histotype, histologic grade, tumor size, estrogen/progesterone receptor status, patient age, and lymph node involvement (P<0.005). In the entire series of patients, both kinetics variables were significantly and independently associated with the clinical outcome, but their prognostic relevance was quite different when node-negative and node-positive patients were considered separately. Although in node-positive patients Ki-67 LI and AgNOR area were the unique independent predictors of disease-free and overall survival, they were excluded by the multivariate Cox model in node-negative patients, where only tumor size and estrogen receptor status retained a significant P-value. These results show that in breast carcinoma the cell growth fraction and the cell proliferation rate have a different prognostic impact with respect to the lymph node status and are major determinants of clinical outcome in node-positive patients only. Within this subgroup, the rapidity of cell proliferation as assessed by AgNOR analysis also served as a sensitive predictor of the response to adjuvant treatments.  相似文献   
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Bilateral congenital absence of the vas deferens (CAVD) is aform of male sterility (found in otherwise normal men) of unknownaetiology. Because males with cystic fibrosis (CF) almost invariablyhave CAVD as well, we investigated the hypothesis that men withisolated CAVD might share a common genetic background with maleswith CF. Genetic testing for CF was carried out in three generationsof subjects: 44 patients with CAVD and their wives, 24 of theirparents, and 13 of their offspring generated by microsurgicalepididymal sperm aspiration (MESA) and in-vitro fertilization(IVF). DNA extracted from peripheral lymphocytes was amplifiedby the polymerase chain reaction (PCR) and then analysed for12 mutations in the cystic fibrosis transmembrane conductanceregulatory (CFTR) gene. Among 44 patients tested with CAVD,26 (59%) were positive for at least one CF mutation, while thecarrier frequency for CF mutations in the general populationis only 4%. Four patients were found to be compound heterozygotes,three with genotypes Delta F-508/R117H, one with R553X/R117H.Among 24 parents tested, 15 (seven fathers, eight mothers) hadsons with CAVD who were positive for CF mutations. Of these,nine (four fathers and five mothers) were found to be carriersfor CF mutations. These four fathers, although carriers of CFmutations, were obviously fertile. Of the 13 offspring tested,six (three boys and three girls) had CF positive fathers. Ofthese, three (two girls and one boy) were found to be carriersfor CF mutations. These MESA/IVF children are the first offpsringto whom men with CAVD have been able to transmit CF mutations.All of the MESA/IVF male offspring (like their grandfathers)had a normal vas deferens bilaterally, including one carrierfor Delta F-508. This study revealed, by genetic testing ofotherwise normal men with sterility caused by CAVD, a new populationof patients with a variant form of CF and highlighted the possibilitythat carrier frequency for CF is higher than previously thought.Compound heterozygosity for CF mutations and not carrier conditionis associated with isolated CAVD. It is concluded that geneticcounselling and screening for CF should be offered to couplesundergoing sperm aspiration and IVF procedures when CAVD isa factor in their infertility.  相似文献   
19.
A functional analysis of tumor-infiltrating lymphocytes (TILs) from renal cell carcinoma (RCC) and malignant melanoma was performed. TILs were expanded in recombinant interleukin-2 (50 U/ml) in Iscoves medium. Phenotypic and functional (cytolytic vs regulatory) analyses were carried out with the fresh and expanded TIL populations after 4 weeks in culture. Only one TIL population from an RCC case (out of six cases studied) was CD8+ and demonstrated MHC class I-restricted tumor-specific cytotoxicity against the autologous RCC target. TIL populations from the other five cases became predominantly CD4+ and they neither killed the respective autologous tumor cells nor killed the NK-sensitive target K-562 cells. When studied for other functions, two CD4+ TIL populations were found to suppress the lymphokine-activated killer cell response by peripheral blood lymphocytes (PBL) in coculture. Of these two, a TIL population from an RCC case (MJ TIL) was used to study the cellular and molecular mechanisms of suppression. The MJ TIL synthesized a supernatant factor that blocked activation of resting PBL as measured by the induction of high-affinity IL-2 receptor (IL-2R) when stimulated by phytohemagglutinin but did not down-regulate the fully expressed IL-2R on activated T cells. The suppression of high-affinity IL-2R induction on T cells did not result from tumor necrosis factor-alpha and beta or from transforming growth factor-beta as these cytokines were not detected in the cell-free supernatant from the MJ TIL culture. The supernatant factor also suppressed IL-2-mediated enhancement of cytotoxicity by natural killer (NK) cells without demonstrating direct toxic effect on the NK cells. Thus, when TIL are used for adoptive immunocytotherapy, it may be useful to fully characterize them functionally, in vitro.  相似文献   
20.
Titanium (Ti) endosseous dental screws with different surfaces (smooth titanium--STi, titanium plasma-sprayed-TPS, alumina oxide sandblasted and acid-etched--Al-SLA, zirconium oxide sandblasted and acid etched--Zr-SLA) were implanted in femura and tibiae of sheep to investigate the biological evolution of the peri-implant tissues and detachment of Ti debris from the implant surfaces in early healing. Implants were not loaded. Sections of the screws and the peri-implant tissues obtained by sawing and grinding were analysed by light microscopy immediately after implantation (time 0) and after 14 days. All samples showed new bone trabeculae and vascularised medullary spaces in those areas where gaps between the implants and host bone were visible. In contrast, no osteogenesis was induced in the areas where the implants were initially positioned in close contact with the host bone. Chips of the pre-existing bone inducing new peri-implant neo-osteogenesis were surrounded by new bone trabeculae. The threads of some screws appeared to be deformed where the host bone showed fractures. Ti granules of 3-60 microm were detectable only in the peri-implant tissues of TPS implants both immediately after surgery and after 14 days, thus suggesting that this phenomenon may be related to the friction of the TPS coating during surgical insertion.  相似文献   
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