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Experiments 1 and 2 address the controversy regarding the reliability of methamphetamine effects on interval timing. A temporal discrimination procedure was used, in which the rats were reinforced for pressing the left or the right levers after short and long signals, respectively. Methamphetamine (0.5 mg/kg sc) severely disrupted operant performance at 20-100 min after injection, which disabled the measurement of drug effects on temporal perception (Experiment 1). The same dose of methamphetamine shifted the psychometric function to the left at 100-180 min after injection, indicating an increase in subjective durations (Experiment 2). Although these results confirm the role of dopamine in interval timing, that a change in the speed of a neural clock mediates the methamphetamine-induced change in temporal perception is still a working hypothesis.  相似文献   
74.
Yavuz O  Cam M  Bukan N  Guven A  Silan F 《Acta histochemica》2003,105(3):261-266
The aim of the present study was the evaluation of possible protective effects of melatonin against beta-cell damage in streptozotocin-induced diabetes in rats. Malondialdehyde levels and glutathione peroxidase activity were measured in pancreatic homogenates. Pancreatic beta-cells were examined by immunohistochemical methods. Streptozotocin was injected intraperitoneally at a single dose of 60 mg/kg for induction of diabetes. Melatonin (200 microg/kg/day, ip) was injected for 3 days prior to administration of streptozotocin; these injections were continued until the end of the study (4 weeks). Streptozotocin induced a significant increase in malondialdehyde levels (p < 0.01) and a significant decrease in glutathione peroxidase activity (p < 0.05) in pancreatic tissue. Degeneration of islet cells and weak immunohistochemical staining of insulin was observed in diabetic rats. Treatment of diabetic rats with melatonin markedly reduced malondialdehyde production (p < 0.05) and increased glutathione peroxidase activity (p < 0.01) without affecting hyperglycemia. Increased staining of insulin and preservation of islet cells were apparent in the melatonin-treated diabetic rats. These data suggest that melatonin treatment has a therapeutic effect in diabetes by reduction of oxidative stress and preservation of pancreatic beta-cell integrity.  相似文献   
75.
BACKGROUND: The purpose of the present correlative immunohistochemical study was to assess the utility of cytokeratin (CK7 and CK20) expression in the diagnosis of short-segment Barrett esophagus, particularly its efficacy in differentiating Barrett mucosa from intestinal metaplasia of the gastric cardia and corpus. METHODS: Two groups of endoscopic biopsy specimens were examined, including 20 endoscopic biopsy specimens of short-segment Barrett esophagus (Group A) and equal number exhibiting Helicobacter pylori associated intestinal metaplasia of the gastric cardia and corpus (Group B). All were investigated by immunohistochemistry using the standard ABC method for CK7 and CK20 expression. Fisher's exact test was used for statistical analysis of Barrett CK7/20 and gastric CK7/20 patterns between the groups. RESULTS: The anticipated pattern of reactivity in Barrett mucosa (CK7: strong diffuse positivity in superficial and deep glands; CK20: positivity in surface epithelium and superficial glands) was seen in 2 cases of Group A specimens. The expected gastric pattern (CK7: patchy immunostaining with variable involvement of deep glands; CK20: patchy immunostaining of superficial and deep glands in incomplete intestinal metaplasia / absence of CK7 immunoreactivity with strong CK20 staining in superficial and deep glands in complete intestinal metaplasia) was seen in 8 cases of Group B specimens. The respective sensitivity and false-negativity values of CK7/20 staining for Barrett pattern in Group A were 10% and 90%, respectively. These values for gastric pattern in Group B were 40% and 60%, respectively. The specificity and false-positivity values of both patterns were same (100% and 0%, respectively). There was no statistically significant difference for Barrett pattern between the two groups (P = 0.487), while the observation of gastric pattern was significantly higher in Group B than in Group A (P = 0.02). CONCLUSIONS: We concluded that these hypothesized and recently applied diagnostic criteria involving CK7 and CK20 immunoreactivity are not reliable in distinguishing short-segment Barrett esophagus from intestinal metaplasia as seen in gastric cardia and corpus.  相似文献   
76.
Heterozygous variants in the arginine‐glutamic acid dipeptide repeats gene (RERE) have been shown to cause neurodevelopmental disorder with or without anomalies of the brain, eye, or heart (NEDBEH). Here, we report nine individuals with NEDBEH who carry partial deletions or deleterious sequence variants in RERE. These variants were found to be de novo in all cases in which parental samples were available. An analysis of data from individuals with NEDBEH suggests that point mutations affecting the Atrophin‐1 domain of RERE are associated with an increased risk of structural eye defects, congenital heart defects, renal anomalies, and sensorineural hearing loss when compared with loss‐of‐function variants that are likely to lead to haploinsufficiency. A high percentage of RERE pathogenic variants affect a histidine‐rich region in the Atrophin‐1 domain. We have also identified a recurrent two‐amino‐acid duplication in this region that is associated with the development of a CHARGE syndrome‐like phenotype. We conclude that mutations affecting RERE result in a spectrum of clinical phenotypes. Genotype–phenotype correlations exist and can be used to guide medical decision making. Consideration should also be given to screening for RERE variants in individuals who fulfill diagnostic criteria for CHARGE syndrome but do not carry pathogenic variants in CHD7.  相似文献   
77.

Purposes

In this study, we sought to establish the value of a new molecule, urocortin (Ucn), in the diagnosis of endometrioma and compare with Ca-125 to identify superiority of urocortin.

Methods

Of the patients operated on at our hospital with the initial diagnosis of adnexal mass, 88 patients whose pathology results were endometrioma and benign ovarian cyst were included in the study. As a result of the pathological examination, the patients were assessed in two groups. Group 1 consisted of 42 cases of endometrioma and Group 2 included 46 cases of benign ovarian cyst (control group). The serum Ucn and CA 125 levels of patients were measured from the blood samples drawn prior to the operation.

Results

While the serum Ucn level was 4.8?±?1.00?ng/ml in the endometrioma group, it was 4.5?±?1.03?ng/ml in the control group (P?=?0.21). The difference was statistically not meaningful. On the other hand, mean serum Ca-125 level was 43.8?U/l (11.7?C251) in the endometrioma group, it was 16.5?U/l (4.3?C121.1) in the control group. The difference was statistically meaningful (P?=?0.001). When the cut-off point for Serum Ca-125 level was taken as 21.38, sensitivity and specificity levels were found to be 88.1 and 63%. When the cut-off point for Ucn was taken as 4.16, sensitivity was 76.2%, and specificity 45.7%.

Conclusion

Ucn was not found to be efficient in distinguishing endometrioma from other benign ovarian cysts or to be superior to CA125 in the diagnosis of endometrioma.  相似文献   
78.

Objective

The finding that ischemia-modified albumin (IMA) is increased in pre-eclamptic pregnancy suggests a role for IMA as a potential biomarker for abnormal placental development related to miscarriage. This study was undertaken to evaluate IMA levels in women with recurrent pregnancy loss (RPL).

Study design

This case-control study was performed between March 2008 and September 2009, at the Department of Obstetrics and Gynecology of Meram School of Medicine. Serum IMA and albumin concentrations were assessed in 43 women with a history of two or more unexplained first trimester miscarriages (group 1), and 42 healthy pregnant women (group 2) in the first trimester. IMA, adjusted IMA and albumin concentrations were compared between the groups. Statistical analysis was performed using Student's t-test and Mann-Whitney U test.

Results

IMA and adjusted IMA levels were significantly higher in women with RPL (1.11 + 0.08 and 1.09 + 0.09, respectively) compared to women in group 2 (0.88 + 0.10 and 0.88 + 0.11, respectively). Albumin levels in group 1 were significantly lower compared with group 2. There was a negative correlation between IMAand albumin levels in each group.

Conclusion

Maternal IMA levels appear to be elevated in women with early RPL. This finding may suggest that an abnormally high hypoxic intrauterine environment may be associated with abnormal placental development that contributes to early miscarriage.  相似文献   
79.
ObjectivesTo describe the clinical characteristics of the pregnant women who were hospitalized in a tertiary referral hospital with pandemic influenza H1N1 2009 virus infection and neonatal outcomes from October 2009 to December 2009 during which the pandemic influenza cases peaked in Turkey.Materials and MethodsTwenty-five pregnant women who were hospitalized with influenza-like illness and who had laboratory confirmation for pandemic influenza H1N1 virus infection were evaluated prospectively.ResultsOf the 25 patients, 4 (16%) were in the first trimester, 8 (32%) were in the second trimester, and 13 (52%) were in the third trimester. The median time from the onset of symptoms to the initiation of antiviral therapy was 1 day (range 1–9 days). Nineteen (76%) patients received oseltamivir treatment. It took 1.6 days on the average for the fever defervescence after the initiation of treatment or hospitalization. Of the 14 patients who underwent chest radiography, three had findings consistent with pneumonia. The mean duration of hospitalization was 4.8 days. Four women (16%) were admitted to an intensive care unit, but there were no maternal or neonatal deaths in this series. At the time of their H1N1 hospitalization, seven women delivered by cesarean at 33–40 weeks gestation, two vaginally at 38 weeks gestation, and two had an abortion at 10 weeks and 16 weeks of gestation, respectively. None of the infants had any evidence of influenza infection.ConclusionPregnant women are at increased risk for complications from pandemic influenza H1N1 virus infection. Timely medical attention with early recourse to antiviral therapy is associated with a better outcome in H1N1-affected pregnant women.  相似文献   
80.
Morphology of the lumbar spinal canal in normal adult Turks   总被引:2,自引:0,他引:2  
Pathological changes can occur in the diameters of the lumbar spinal canal. Therefore, assessing the canal size an important diagnostic procedure. Two hundred plain anterioposterior radiographs of the lumbar spine were examined. The sample consisted of 100 males and 100 females. The transverse diameter of the bony spinal canal (interpedicular distance), which was measured as the minimum distance between the medial surfaces of the pedicles of a given vertebra, was measured. In addition, the transverse diameter of the vertebral body, which was measured as the minimum distance across the waist of the vertebra, was measured. The distances were measured to the nearest one tenth of a millimetere using a Vernier caliper. At all levels (L1 - L5) the transverse diameters of the lumbar spinal canal were approximately 1 - 1.5 mm higher in males than in females. The intersegmental differences increased proximodistally, in both sexes. The ratio of the transverse diameter canal to the width of the vertebra ranged from 0.55 to 0.60 mm in both sexes. The distribution of the different lumbar canal types were 47% A, 42% B, 11% C. Additionally, subtypes were determined and classified.  相似文献   
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