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991.
Intra-hepatic cholestasis of pregnancy in hepatitis C virus infection   总被引:3,自引:0,他引:3  
BACKGROUND: Aims of this study were to investigate whether hepatitis C virus infection influences the incidence and natural history of intrahepatic cholestasis of pregnancy (ICP) and whether ICP has different characteristics in hepatitis C virus (HCV) positive women from ICP in HCV negative women. METHODS: A prospective study for the prevalence of the HCV infection and for the incidence of ICP was carried out in the 5840 patients admitted to the Prenatal Department of Padua University, Italy, between January 1996 and January 1999. Testing was done for HCV by the enzyme linked immunosorbent assay (ELISA 3), recombinant immuno blot assay (RIBA 3) and polymerase chain reaction (PCR). The diagnosis of ICP was made on clinical grounds based on the occurence of pruritus with onset during pregnancy, persisting up to the time of delivery and disappearing after delivery, supported by demonstrating an elevation of both serum ALT and total serum bile acids. The Student's t-test, one way anova and chi-square tests were used for statistical analysis. RESULTS: During the study period, 56 of 5840 patients developed ICP (0.96%). Of these, 12 were also HCV-RNA positive. The rate of ICP was observed more commonly in HCV-RNA positive women than in HCV-RNA negative women (20.33% or 12/59 versus 0.78% or 44/5767, P = 0.001 CONCLUSIONS: Occurrence of ICP during the third trimester should be an indication to investigate the HCV status of the patient. Although the diagnosis of ICP is not confirmed by specific tests, we confirmed a higher risk of HCV infection in this condition. Therefore, occurence of ICP during the third trimester should be an indication to investigate the HCV status of the patient. Broader studies are necessary to assess the impact of infection on the perinatal outcome of ICP.  相似文献   
992.
The aim of this study was to evaluate the hypothesis that the association between nutritional status and gender of rat pups during the early postnatal period (lactation) induces changes in glucose homeostasis and blood pressure of the pups when becoming adults. The results indicate that undernourishment during lactation is associated with gender and affects glucose homeostasis and blood pressure of female adults. In our experiments, the blood glucose level at the end of a clamping was significantly different in the undernourished females (FU) compared with the female controls (FC) (FC: 11.2 +/- 0.9 mmol/l; FU: 26.9 +/- 2.1 mmol/l; p 相似文献   
993.
994.
OBJECTIVE: To identify the predictive factors (with emphasis on diagnostic delay) associated with the diagnosis of an advanced-clinical stage head and neck cancer. DESIGN: Cross-sectional study of patients with head and neck cancer originally recruited for a case-control study. SETTING: Three referral oncological centers in metropolitan areas in southern Brazil: S?o Paulo, Curitiba, and Goiania. PATIENTS: The study population comprised 679 patients recently diagnosed as having a previously untreated head and neck squamous cell carcinoma. MAIN OUTCOME MEASURE: Diagnosis of advanced disease (clinical stage III-IV) head and neck cancer. RESULTS: Patients with laryngeal and hypopharyngeal cancers were more likely to be diagnosed as having advanced disease than those with lip, oral, and oropharyngeal cancers (88.0% vs 74.6%) (P<.001). Patient delay was inversely associated with clinical stage at diagnosis in patients with the same cancers, while professional delay was directly associated with a higher risk of advanced clinical stage at diagnosis (P =.001 and P =.006, respectively). In the analysis of laryngeal and hypopharyngeal cancer, both patient and professional delays were associated with advanced disease, with patient delay being a stronger predictive factor than professional delay. CONCLUSIONS: Clinical stage at diagnosis was associated with sociodemographic characteristics, patient delay, and professional delay. Our results indicate that continued educational programs for the population and health care professionals regarding the identification of early symptoms of head and neck cancers are warranted.  相似文献   
995.
OBJECTIVE: To determine the factors that contribute to the pathogenesis of isolated systolic hypertension in children. METHODS: School-based measurement was performed of blood pressure (BP), heart rate, weight, and height in 2460 students (49% Hispanic, 31% black, 13% white) 12 to 16 years of age in 8 urban public schools. An independent group of 71 untreated children underwent 24-hour ambulatory BP monitoring (ABPM) to confirm clinic hypertension and assess circadian BP patterns. RESULTS: Hypertension and obesity were found in 17% and 23% of students, respectively. Among hypertensive students, 88% (363/413) had isolated systolic hypertension. Hypertension was more prevalent in obese than nonobese students (33% vs 11%, P <.0001). Obese hypertensive students had higher resting heart rate than nonobese normotensive patients (85.9 vs 79.6 beats/min, P <.001). Among patients who underwent ABPM, isolated systolic hypertension was found in 51% (36/71) by clinic BP and in 62% (18/29) with confirmed hypertension by ABPM. Blood pressure variability during daytime and sleep periods was higher in obese than nonobese patients for systolic BP (P <.01) and diastolic BP (P <.05). CONCLUSIONS: The findings of increased heart rate and BP variability in obese children with isolated systolic hypertension suggest that sympathetic nervous system hyperactivity may contribute to its pathogenesis.  相似文献   
996.
Purpose : The emotional changes provoked by the use of assisted reproduction techniques (ART) may trigger important psychological reactions. The objective of the present study was to develop a psychological evaluation test (PET–ART) in order to identify the occurrence of psychological problems and to facilitate their treatment. Methods : A total of 128 women were submitted to PET–ART of the Center for Human Reproduction, Sinhá Junqueira Maternity Foundation, after application of IVF/ICSI program at least once. The causes of infertility were male-related in 45% of cases, female-related in 48%, and both male- and female-related in 7%. Infertility was primary in 79% of cases and secondary in 21%. The mean age of the women was 34.5 ± 5.2 years and the mean age of the men was 37.9 ± 6.8 years. The PET–ART was evaluated using a questionnaire with 15 questions selected in order to detect emotional reactions caused by infertility. The responses were assigned four grades with respect to intensity (1 = mild intensity; 2 = medium intensity; 3 = high intensity; and 4 = maximum or unbearable intensity). The sum of the responses corresponded to PET–ART score ranging from 15 to 60 points. The reliability of the questionnaire was evaluated by the alpha coefficient of Cronbach. Results : The PET–ART identified five questions receiving 50% or more responses of the high/maximum intensity type (sum of the percentages of responses with a score of 3 and 4). The questions were the following: 1—The waiting time before being submitted to a pregnancy test (82.8% of the patients); 2—A negative result of the pregnancy test (77.3% of the patients); 3—The degree of anxiety in a new attempt to obtain pregnancy (76.5% of the patients); 4—Finding the money necessary for the repetition of the IVF/ICSI techniques (66.4% of the patients); 5—The possibility of collecting few eggs, or of forming or not an embryo in the laboratory is an expectation that makes me anxious (57.8% of the patients). The mean PET–ART was 33 ± 6. The alpha coefficient of Cronbach was 0.757. Conclusions : The PET–ART was an efficient tool for the identification of women with emotional changes provoked by the application of ART and for the planning of their treatment. However, a general psychological approach was developed for each emotional factor regardless of PET–ART.  相似文献   
997.
Denaturing high performance liquid chromatography (DHPLC) in combination with dye-terminator sequencing was used to survey 516 random genomic sequence tagged sites (STSs) for biallelic polymorphisms in 24 representatives of the major ethnic groups residing in the United States. Of the 301 polymorphic STSs (58.3%), 172 contained a single simple sequence polymorphism (SSP), while 78, 35, and 16 contained 2, 3, and 4-6 SSPs, respectively. Of the 541 SSPs identified, 342 (63%), 152 (28%), and 47 (9%) were transitions, transversions, and insertions or deletions, respectively. Only 21% of the STSs contained SSPs with a minor-allele frequency >20%. The nucleotide diversity estimate for random genomic sequences theta = 8.23 x 10(-4) was on average 50% higher than that for intragenic non-coding regions of the human genome ( theta = 5.52 x 10(-4). The discrepancy in Tajima's D statistic between 22 autosomal genes (D=-1.304+/-0.622, mean+/-SD) and random STSs (D=-0.27) suggests that, in the absence of significant mutation rate heterogeneity, the more negative values for genes are a consequence of directional selection rather than population growth.  相似文献   
998.
In the early eighties, in the US the advantages (reduced costs, no hospitalisation trauma in children, no immobilization syndrome in elderly, reduction of nosocomial and acquired infections by multi-resistant organisms) of OPAT were identified and suitable therapeutic programs were established. Following the US experience, other countries set up their own OPAT programs which vary considerably from country to country because of different ways in which infections are managed in different parts of the world and because of different reimbursement systems. In order to understand the ways of managing OPAT and its results, a National OPAT Registry was set up in 1999 in Italy belonging to a wider International OPAT database, which collects data also from USA, Canada, Spain, Uruguay and Argentina. Up to now 396 patients and as many antibiotic courses have been included in the National Registry by eight different centres. The analysis of data permits to get information about the criteria of patient's selection, treatment (route of administration, site of care, choice of antibiotic, dosage and duration), outcomes and possible side-effects. Italian results offer a quite peculiar picture of OPAT in this country when comparing data with those of other countries. In contrast with other countries where soft tissue infections and osteomyelitis are the most frequent diagnoses for including patients in OPAT programmes, in Italy pneumonia and bronchitis are the top two amenable infections. Ceftriaxone, Teicoplanin and Amikacin are absolutely the top three antibiotics selected for OPAT in Italy which confirm that a single daily dose regimen represents a great advantage in terms of compliance. Finally, a large percentage of antibiotic courses (50%) are carried out by using the i.m. administration route, which is very unusual in other countries. OPAT Registry is still ongoing and it will give us more detailed information in the future about the management of infections in the outpatient setting, but it already permits to define an actual picture of OPAT in our country and/or to compare and correlate data and information from different countries.  相似文献   
999.
1000.
Twenty-four Mediterranean fin whales were tracked in open sea with a method based on the assessment of the animal differential position in respect of the observer's absolute position aboard a vessel, with the concomitant recording of the respiratory activity. Short distance video recording was also performed in two whales, permitting the simultaneous determination of single breath expiratory (TE) and inspiratory (TI) durations. In the 24 whales swimming at an average velocity of 1.39 (0.47) m·s–1 [mean (SD), range: 0.62–2.44 m·s–1], 2068 breaths organized in 477 respiratory cycles were observed. Each cycle entailed a prolonged apnoea dive phase [225 (91) s, Tdive) followed by a period near the surface [62 (28) s, surfacing], during which a series of breaths [4.6 (1.8)] was performed at short intervals. On the basis of track length and swimming velocity, two groups of animals were devised differing for convolution of the course (p<0.001), extension of ranging territory (p<0.01) and horizontal swimming velocity (p<0.05), which may represent two distinct behaviours. A possibly general mechanism of control of breathing in cetaceans was found, consistent with a model of constant tidal volume and variable respiratory frequency. Coherently with this model, TE was independent of TI or Tdive, in line with a passive expiration, while TI appeared to be negatively correlated with Tdive (p<0.05), otherwise suggesting, similarly with terrestrial mammals, a significant role of hypercapnic stimulation. The estimated O2 consumption of about 150 l·min–1 is in line with the general allometric regression for mammals and corresponds to an energetic expenditure of 85–95 kJ·kg–1·day–1.Partially presented as a poster at The World Marine Mammal Science Conference and 12th Annual Conference of the European Cetacean Society, Monaco (Montecarlo), 20–24 January 1998.Angelo Colombini provided technical assistance.  相似文献   
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