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101.
Neurobehavioral and somatic effects of perinatal PCB exposure in rats   总被引:5,自引:0,他引:5  
Developing rats were exposed to PCBs via provision of diets containing 0.02 (no PCB added), 2.5, 26, or 269 ppm Aroclor 1254 to sperm-positive female rats from mating to weaning of their pups. Provision of the 269 ppm diet decreased the number of impregnated rats that delivered a litter and lowered pup birth weight, and most pups died within 7 days of birth. Pregnancy success, pup birth weight, and dam body weight and food intake were not altered in the 2.5 and 26 ppm conditions. Preweaning pup growth was reduced in the 26 ppm condition and slightly reduced in the 2.5 ppm condition. The ontogeny of negative geotaxis, auditory startle, and air righting was delayed in pups from the 26 ppm condition. Pups in the 2.5 ppm condition had slightly delayed development of auditory startle. PCB exposure did not affect the duration of forepaw suspension or age at eye opening. Maximal electroshock seizure tests on postweaning rats showed that perinatal PCB exposure decreased seizure severity of both the 2.5 and 26 ppm groups as indicated by increased durations of forelimb and hindlimb flexion and decreased duration of hindlimb extension. PCB exposure increased pup liver weights at birth and dam and pup liver weights at weaning. Spleen and thymus weights were lower in PCB-exposed pups, while brain weights were unaffected. Analytical determination of PCB levels in brain showed greater maternal transfer of PCBs during lactation than during gestation. Elevated PCB levels were detectable in brains of perinatally exposed adult rats. The results indicate that perinatal PCB exposure of rats alters neurobehavioral and somatic ontogeny.  相似文献   
102.

Introduction and hypothesis

The causal association between pelvic organ prolapse (POP) and overactive bladder (OAB) symptoms is supported by several theories. The aim of this study is to assess any changes in OAB symptoms among women with POP and OAB after successful pessary placement.

Methods

During the study period, all women with symptomatic POP stage II or greater and OAB symptoms were offered the solution of either a ring or a Gellhorn pessary. All patients were asked to complete a 3-day micturition/incontinence diary. Objective evaluation endpoints at baseline and at 6 weeks included: change in the mean number of micturitions/24 h, change in the mean volume voided per micturition/24 h, and change in the number of urinary incontinence episodes. Subjective evaluation of the urgency, frequency, and nocturia symptoms was carried out using the score change of the questions 3, 5, and 2 of the International Consultation on Incontinence Questionnaire for Evaluating Female Lower Urinary Tract Symptoms (ICIQ-FLUTS) respectively.

Results

Seventy-four women were included in the study. A statistically significant decrease (?28.3%; p < 0.001) of the mean number of micturitions/24 h with a significant increase (37%; p < 0.001) in the mean voided volume per micturition/24 h was observed. The total urine volume/24 h remained unchanged. The number of urinary incontinence episodes was significantly increased 6 weeks after pessary placement (p < 0.001). De novo stress urinary incontinence (SUI) was reported by 16.7% of the initially stress continent women.

Conclusions

Women with coexisting POP and OAB symptoms may experience a significant improvement in micturition frequency and in urgency and frequency symptoms after successful pessary fitting.
  相似文献   
103.
OBJECTIVES: The analytical performance of the TOSOH HLC-723G7 hemoglobin HPLC analyzer and the effect of the presence of HbS in the determination of HbA(2) using HPLC and manual column methods. DESIGN AND METHODS: The performance characteristics of the TOSOH HLC-723G7 analyzer in the determination of HbA(2) were compared to those of the HELENA Beta-Thal Quik column. The effect of HbS presence in the samples was quantified using the HELENA SAS-MX alkaline gel electrophoresis kit as the reference method. RESULTS: Within-run and between-run CVs for HbA(2) were better for the TOSOH HPLC analyzer than for the HELENA manual column method. The presence of HbS in the samples produces a strong positive bias in the %HbA(2) values when using both the HPLC and manual column methods, compared to the alkaline electrophoresis gel. CONCLUSION: Both the TOSOH HPLC and the manual column are reliable methods for %HbA(2) determination when no HbS is detectable in the samples. When HbS is present, the gel electrophoresis method gives more accurate results.  相似文献   
104.
The present study aimed to test whether neurocognitive deficits involved in decision making underlie subtypes of conduct-disorder (CD) differentiated on the basis of callous-unemotional (CU) traits. Eighty-five participants (M age = 10.94 years) were selected from a sample of 1200 children based on repeated assessment of CD and CU traits. Participants completed a multi-method battery of well-validated measures of risky decision making and associated constructs of selective attention and future orientation (Stroop, Stoplight, and Delay-Discounting Tasks). Findings indicated that impaired decision making, selective attention, and future orientation contribute to the antisocial presentations displayed by children with CD, irrespective of level of CU traits. Youth high on CU traits without CD showed less risky decision making, as indicated by their performance on the Stoplight laboratory task, than those high on both CD and CU traits, suggesting a potential protective factor against the development of antisocial behavior.  相似文献   
105.
AIM: To prospectively compare partially covered vs uncovered sphincterotome use on post-endoscopic biliary sphincterotomy (ES) hemorrhage and other complications. METHODS: All patients referred for therapeutic endoscopic retrograde cholangiopancreatography (ERCP) were randomly assigned to undergo ES either with a partially covered or an uncovered sphincterotome. Both patient and technical risk factors contributing to the development of post-ES bleeding were recorded and analyzed. The characteristics of blee...  相似文献   
106.
107.

Background

Numerous subsets of patients with chronic lymphocytic leukemia display similar immunoglobulin gene usage with almost identical complementarity determining region 3 sequences. Among IGHV4-34 cases, two such subsets with “stereotyped” B-cell receptors were recently identified, i.e. subset #4 (IGHV4-34/IGKV2-30) and subset #16 (IGHV4-34/IGKV3-20). Subset #4 patients appear to share biological and clinical features, e.g. young age at diagnosis and indolent disease, whereas little is known about subset #16 at a clinical level.

Design and Methods

We investigated the global gene expression pattern in sorted chronic lymphocytic leukemia cells from 25 subset/non-subset IGHV4-34 patients using Affymetrix gene expression arrays.

Results

Although generally few differences were found when comparing subset to non-subset 4/16 IGHV4-34 cases, distinct gene expression profiles were revealed for subset #4 versus subset #16. The differentially expressed genes, predominantly with lower expression in subset #4 patients, are involved in important cell regulatory pathways including cell-cycle control, proliferation and immune response, which may partly explain the low-proliferative disease observed in subset #4 patients.

Conclusions

Our novel data demonstrate distinct gene expression profiles among patients with stereotyped IGHV4-34 B-cell receptors, providing further evidence for biological differences in the pathogenesis of these subsets and underscoring the functional relevance of subset assignment based on B-cell receptor sequence features.  相似文献   
108.
Ischemia-reperfusion injury can be detrimental to the solitary kidney, especially when it is accompanied by ablation. To the authors' knowledge, the effects of partial nephrectomy with prolonged application of ischemia have never been described at the ultrastructural level. Therefore, the authors used an animal model and focused on putative structural effects in the glomerular basement membrane and the podocytes. They demonstrate the advantageous role of cold ischemia, even in up to 120 min. In contrast, more than 60 min of warm ischemia leads to catastrophic lesions in all the cellular structures, as is reflected by mortality due to acute renal failure.  相似文献   
109.
We tested 59 Greek patients with Behcet's Disease (BD) for serum anti-Saccharomyces cerevisiae antibodies. No increase of these antibodies was detected in the cases compared to 55 healthy unrelated blood donors from the same population. This finding is in contrast with the correlation between Saccharomyces cerevisiae antibodies and BD as reported in other populations. It seems that environmental factors may contribute to disease expression in different populations, producing different effects according to the individual's genetic predisposition. Saccharomyces cerevisiae antibodies do not seem to be of any significance in the Greek population.  相似文献   
110.
Objective: The aim of the present study was to evaluate the role of age on different types of liver surgery. Methodology: Between 2002 and 2007, 50 patients underwent a variety of liver surgical procedures due to primary or metastatic tumours. Of these, 24 were 70 years old or older, and 26 patients were younger than 70 years old at the time of the operation. Results: Among the patients included in the study, 22 underwent radiofrequency ablation. Another 11 underwent non‐anatomical liver resection. The remaining 17 patients underwent liver resection, with more than three segments resected. The type of procedure, duration of operation, estimated blood loss, and postoperative death and morbidity rates were not significantly different between the two groups. The mean survival of patients that underwent radiofrequency ablation or non‐anatomical resection was not significantly different between the two groups. However, in the patients in which liver resection was performed, mean survival was significantly greater in the younger group. Conclusions: These results indicate that hepatic resection is a safe and feasible procedure in elderly patients. The postoperative outcome in this age group is comparable of that of younger patients.  相似文献   
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