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1.
Pedro Moral Elisabetta Marini Esther Estebanup Giuseppa Elisa Mameli Valeria Succa Giuseppe Vona 《American journal of human biology》2002,14(1):21-28
Four communities from Guahibo of Venezuela were analyzed for the genetic variants of nine erythrocyte enzymes and five serum proteins. Of the 14 loci determined, four were monomorphic. Significant frequency differentiation among communities, was present for ESD and TF markers. In general, Guahibo allele frequencies are in the variation ranges described for South American groups. The analysis indicates a relatively higher affinity of Guahibos with other Venezuelan groups within an irregular pattern of genetic distances that are likely related to the complex demographic history of the South American groups. Genetic diversity estimates reveal a moderate degree of genetic structure between the four Guahibo communities. This intra‐tribal variability in Guahibo appears to be lower than in Venezuelan Piaroa but higher than in other Amerindians and could be attributed to a combined effect of low population size and relative isolation of communities. At a continental level, the distribution of genetic diversity is consistent with preferential population movements along the eastern and western coastal areas. Am. J. Hum. Biol. 14:21–28, 2002. © 2002 Wiley‐Liss, Inc. 相似文献
2.
A W Dombrowski G F Bills G Sabnis L R Koupal R Meyer J G Ondeyka R A Giacobbe R L Monaghan R B Lingham 《The Journal of antibiotics》1992,45(5):671-678
A novel cytochalasin, L-696,474, (18-dehydroxy cytochalasin H) that inhibits HIV-1 protease was discovered in fermentations of a bark-inhabiting Ascomycete, Hypoxylon fragiforme. The product was first identified from extracts of an agar medium. Fermentation studies on a number of media indicated that the product can be made on several solid and liquid media. Optimum production was obtained from growth in a complex medium composed of glycerol, glucose, citrate, Ardamine, soybean meal, tomato paste, and inorganic salts. Other Hypoxylon spp., related species of Xylariales, and other fungi known to produce cytochalasins, were also surveyed for their ability to make L-696,474. Only one other Hypoxylon fragiforme isolate was found to make this novel cytochalasin; none of the other cultures surveyed made L-696,474 or any other compounds which inhibit HIV-1 protease. 相似文献
3.
OBJECTIVE: To compare the accuracy of ovarian volume, antral follicle count and age in predicting menopausal status in healthy women. METHODS: The cross-sectional study was set in the Gynecology Division at the Leonor Mendes de Barros Maternity Hospital, S?o Paulo, Brazil. The subjects of this study were premenopausal (n = 121) and postmenopausal (n = 71) healthy women aged between 40 and 55 years. They were submitted to a medical interview and transvaginal ultrasound examination. The ovarian volume (cm3), antral follicle count and chronological age were recorded in both groups and the accuracies of these parameters in predicting menopausal status were compared. RESULTS: Premenopausal women presented larger ovaries than postmenopausal women (p < 0.01). Premenopausal women had a higher number of antral follicles than postmenopausal women (p < 0.01). The receiver operating characteristic curves showed that ovarian volume, age and antral follicle count had similar sensitivities and specificities in predicting menopausal status. The best cut-off points were observed when ovarian volume was <4 cm3, age was > or =48 years and antral follicle count was < or = two follicles. CONCLUSIONS: Ovarian volume, antral follicle count and chronological age are all individually predictive of menopausal status, with similar accuracies. 相似文献
4.
Pasquale Spataro Angela Di Pietro Maria Elena Scoglio Giuseppa Visalli Cristina Chirico Isa Picerno 《Renal failure》2013,35(5):441-448
Introduction. Recently, the identification of the SEN virus as a possible etiological agent of parental transmission hepatitis led to the study of the prevalence of such pathogen agents, particularly SENV-H, in our population. This paper compares the rate prevalence in high-risk subjects, such as dialysis patients, and low-risk subjects, such as blood donors. Material and Methods. The study was carried out on SEN virus DNA extracted from serum of dialysis patients and blood donors, and the presence of viral genomes was performed by the nested PCR method. Results. The results showed a higher prevalence in male blood donors, supporting the hypothesis of an epidemiological role for sexual and also parental transmission, as is clearly demonstrated by the high prevalence in dialysis patients. The result reduced the importance of the possible etiological role of the SEN virus due to the high percentage of positivity in healthy population, and it induces one to consider poorly significant the pathogenicity of such viral agents. Conclusion. For this instance, the authors, in agreement with the phylogenically related TT virus, described SEN viruses as absolutely not pathogens and considered them as “simple guests.” 相似文献
5.
Giacobbe Chiara Raimo Simona Cropano Maria Santangelo Gabriella 《Brain imaging and behavior》2022,16(5):2353-2374
Brain Imaging and Behavior - The neural correlates of action language processing are still debated within embodied cognition research and little is known about the flexible involvement of... 相似文献
6.
Grassi N Cipolla C Torcivia A Mandala S Graceffa G Bottino A Latteri F 《World journal of gastroenterology : WJG》2008,14(8):1302-1304
Gastrointestinal stromal tumour (GIST) is a rare tumour of the gastrointestinal tract which does not generally originate in the rectum. The authors describe a case of a 70-year-old man who underwent an anterior resection of the rectum for a low-risk GIST. The patient was not given adjuvant chemotherapy with imatinib and is still disease-free 30 mo after surgery. The authors conclude that although rectal GIST is extremely uncommon, it should be included in differential diagnosis when a tumour in the rectum is detected. Biopsy of the tumour is essential, since this makes it possible to reach a sure preoperative diagnosis based on the immunohistological features of the CDl17 and CD34. Although complete surgical resection with negative tumour margins is the principal curative procedure for primary and nonmetastatic tumours, further studies are still needed for the determination of the most effective treatment strategy for patients with rectal GIST. 相似文献
7.
Luca Masotti Grazia Panigada Giancarlo Landini Filippo Pieralli Francesco Corradi Salvatore Lenti Rino Migliacci Stefano Arrigucci Anna Frullini Maria Chiara Bertieri Stefano Tatini Alberto Fortini Irene Cascinelli Nicola Mumoli Stefano Giuntoli Alessandro De Palma Veronica De Crescenzo Michele Piacentini Giancarlo Tintori Alba Dainelli Giuseppa Levantino Plinio Fabiani Filippo Risaliti Roberta Mastriforti Michele Voglino Valentina Carli Simone Meini 《Journal of thrombosis and thrombolysis》2016,41(4):606-612
Prognostic stratification of acute pulmonary embolism (PE) remains a challenge in clinical practice. Simplified PESI (sPESI) score is a practical validated score aimed to stratify 30-day mortality risk in acute PE. Whether prognostic value of sPESI score differs according to sex has not been previously investigated. Therefore the aim of our study was to provide information about it. Data records of 452 patients, 180 males (39.8 %) and 272 females (60.2 %) discharged for acute PE from Internal Medicine wards of Tuscany (Italy) were analysed. sPESI was retrospectively calculated. Variables enclosed in sPESI score, all cause in-hospital mortality and overall bleedings were compared between sexes. Moreover, predictive ability of sPESI score as prognosticator of all cause in-hospital mortality was tested and compared between sexes. sPESI score 0 (low risk) was found in 17.7 % of males and 13.6 % of females (p = 0.2323). We didn’t find significant difference in sPESI scoring distribution. Age ≥80 years (51.4 vs. 33.8 %, p = 0.0003) and heart rate ≥110 bpm (23.5 vs. 14.4 %, p = 0.0219) were found significantly more prevalent in females, whereas active cancer (23.8 vs. 39.4 %, p = 0.0004) and cardio-respiratory diseases (19.8 vs. 27.7 %, p = 0.0416) were in males. All cause in-hospital mortality was 0 % in both genders for sPESI score 0, whereas it was 5.4 % in females and 13.6 % in males with sPESI score 1–2 (p = 0.0208) and 22 % in females and 19.3 % in males with sPESI score ≥3 (p = 0.7776). Overall bleedings were significantly more frequent in females compared with males (4.77 vs. 0.55 %, p = 0.0189). In females overall bleedings ranged from 2.7 % in sPESI score 0 to 6 % in sPESI score ≥3. Predictive ability of sPESI score as prognosticator of all cause in-hospital mortality was higher in females compared to males (AUC 0.72 vs. 0.67, respectively). In real life different co-morbidity burdens in females compared to males. Females seems to be at lower risk of all cause in-hospital mortality for sPESI score ≤2 but at higher risk of bleeding, irrespective from sPESI scoring. Predictive ability of sPESI score seems better in females. 相似文献
8.
9.
Visalli G Bertuccio MP Currò M Pellicanò G Sturniolo G Carnevali A Spataro P Ientile R Picerno I Cavallari V Piedimonte G 《AIDS research and human retroviruses》2012,28(9):1110-1118
Regressive morphological lesions, found in peripheral lymphocytes from HIV(+) patients, clearly conflict with normal cycle progression and with the execution of basic housekeeping and immune functions. With these lesions, circulating lymphocytes are destined to spontaneous and energy-independent cell lysis. By means of confocal microscopy and morphometry, we have quantified the rate of circulating T cells that are probably destined to emocatheresis in vivo. This rate includes lymphocytes in which nucleolin fragments have been scattered out of the nuclear region as a result of prelethal alterations in the nuclear membrane permeability. In terms of bioenergetics, these cells show evident anomalies in the energy production machinery that make them unable to carry out ATP-requiring functions. The extent of damaged cell fraction in peripheral blood reflects the frequency with which T lymphocytes leave lymphoid tissue to be cleared in hemocatheretic processes. 相似文献
10.
Mucins in the gastrointestinal tract of Rhinolophus ferrumequinum were investigated by histochemistry and lectin histochemistry to evaluate morphofunctional variations of different regions and their possible physiological and evolutionary implications. Histochemical methods included periodic acid-Schiff (PAS), Alcian blue (AB) at pH 2.5 and 1.0 and high-iron-diamine AB pH 2.5. Binding of lectins Con A, DBA, WGA, LTA, LFA, PNA and SBA; LFA, PNA and SBA with prior sialidase treatment; and paradoxical Con A were evaluated. The oesophagus lacked glands. The stomach was divided into a short cardias, a wide fundus and a brief pylorus. The surface muciparous cells secreted sulpho- and sialomucins with N-acetylgalactosamine (GalNAc) residues, N-acetyllactosamine and (beta1,4 N-acetylglucosamine)(n) chains. Towards the pylorus, N-acetylgalactosamine residues disappeared and acidity decreased. Cardiac glands, neck cells in the fundic glands, pyloric and duodenal Brunner's glands all shared neutral, stable class-III mucins, mainly with N-acetylgalactosamine sequences. The intestine was divided into a duodenum, a jejuno-ileum and a short rectum. The goblet cells produced sulpho- and sialomucins with sialylated N-acetylgalactosamine sequences, (beta1,4 N-acetylglucosamine)(n) and N-acetyllactosamine, whose sialylation increased towards the rectum. The main features of the mucins are probably associated with the requirements of fast absorption and food passage and in protection against mechanical and pathogenic injuries. 相似文献