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1.
Low molecular weight heparins are widely used in the prophylaxis and treatment of thrombotic disorders. The effect of low molecular weight heparins on coagulation was examined ultrastructurally in an animal model. A test and a control group was formed, each consisting of five rabbits. Nadroparine (225 Institute of Chaoy Unit/kg twice daily) was applied to the test group for 10 days. The control group received 1 ml saline solution subcutaneously. Blood and vascular tissue samples collected at the end of the 10th day were evaluated under a JEM 100 B electron microscope. Platelet degranulation and agglutination was observed in the control group. Fibrin materials were detected in the cytoplasms and surroundings of degranulated platelets. Erythrocyte accumulation was remarkable on the vascular endothelium with intact coagulation periods. In the test group, outer membranes of platelets, hyalomere, and granular structures in the granulomeres were detected to be nearly intact. There were rare erythrocytes in the large vascular lumens. The aggregation phase had occurred but no agglutination was detected. Nadroparine seems to preserve consistency of lipoprotein membranes of platelets and granular structures containing enzymes, which contribute to the coagulation mechanisms.  相似文献   
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In living donor liver transplantation (LDLT), obtaining the precise volume of the graft is very important to decrease volume-related postoperative complications, especially in cases with suspected small-for size grafts. We used stereology based on the Cavalieri method (CM), a new method to measure liver graft volume, and compared the results with those obtained through intraoperative measurement (IOM) and through multidetector computed tomography (MDCT) measurement. Liver volumes estimated using the 3 methods were well-correlated with each other (r(2) = 0.94 and P < 0.001 for IOM and CM; r(2) = 0.91 and P < 0.001 for IOM and MDCT, and r(2) = 0.95 and P < 0.001 for CM and MDCT); however, they were different from each other (in descending order, 908 +/- 124 cm(2), 861 +/- 121 cm(2), and 777 +/- 168 cm(2) for MDCT, CM, and IOM, respectively). Although MDCT and CM overestimated the volumes, the results of CM were almost similar to those obtained via IOM. In conclusion, our results suggest that CM measured the liver graft volume more reliably. Thus, its use, particularly in cases with suspected small-for-size graft, may prove useful.  相似文献   
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We investigated the neurobiological basis of variation in sensitization between three aplysiid species: Aplysia californica , Phyllaplysia taylori and Dolabrifera dolabrifera . We tested two different forms of sensitization induced by a noxious tail shock: local sensitization, expressed near the site of shock, and general sensitization, tested at remote sites. Aplysia showed both local and general sensitization, whereas Phyllaplysia demonstrated only local sensitization, and Dolabrifera lacked both forms of learning. We then investigated a neurobiological correlate of sensitization, heterosynaptic modulation of sensory neuron excitability by tail-nerve stimulation. We found (1) an increase in sensory neuron (SN) excitability after both ipsilateral and contralateral nerve stimulation in Aplysia , (2) a smaller and shorter-lasting increase in Phyllaplysia , and (3) no effect in Dolabrifera . Because sensitization in Aplysia is strongly correlated with serotonergic (5-HT) neuromodulation, we hypothesized that the observed interspecific variation in sensitization and SN neuromodulation might be correlated with variation in the anatomy and/or functional response of the serotonergic system. However, using immunohistochemistry, we found that all three species showed a similar pattern of 5-HT innervation. Furthermore, they also showed comparable 5-HT release evoked by tail-nerve shock, as measured with chronoamperometry. These observations indicate that interspecific variation in learning is correlated with differences in SN heterosynaptic plasticity within a backgound of evolutionary conservation in the 5-HT neuromodulatory pathway. We thus hypothesize that evolutionary changes in learning phenotype do not involve modifications of the 5-HT pathway per se , but rather, changes in the response of SNs to the activation of this or other neuromodulatory pathways upon noxious stimulation.  相似文献   
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We present a new case of Pilomatrix Carcinoma after having review the 22 cases previously published. The tumor arisen in a 74 years old male, in the left preauricular region. The lesion was excised with wide margins. A year after there is not any evidence of recurrence or metastases.  相似文献   
9.

Background

Intimate partner violence (IPV) against women is a global public health problem, yet data on IPV against Native American women are extremely limited. We conducted a cross-sectional study of Native American women to determine prevalence of lifetime and past-year IPV and partner injury; examine IPV in relation to pregnancy; and assess demographic and socioeconomic correlates of past-year IPV.

Methods

Participants were recruited from a tribally-operated clinic serving low-income pregnant and childbearing women in southwest Oklahoma. A self-administered survey was completed by 312 Native American women (96% response rate) attending the clinic from June through August 1997. Lifetime and past-year IPV were measured using modified 18-item Conflict Tactics Scales. A socioeconomic index was created based on partner's education, public assistance receipt, and poverty level.

Results

More than half (58.7%) of participants reported lifetime physical and/or sexual IPV; 39.1% experienced severe physical IPV; 12.2% reported partner-forced sexual activity; and 40.1% reported lifetime partner-perpetrated injuries. A total of 273 women had a spouse or boyfriend during the previous 12 months (although all participants were Native American, 59.0% of partners were non-Native). Among these women, past-year prevalence was 30.1% for physical and/or sexual IPV; 15.8% for severe physical IPV; 3.3% for forced partner-perpetrated sexual activity; and 16.4% for intimate partner injury. Reported IPV prevalence during pregnancy was 9.3%. Pregnancy was not associated with past-year IPV (odds ratio = 0.9). Past-year IPV prevalence was 42.8% among women scoring low on the socioeconomic index, compared with 10.1% among the reference group. After adjusting for age, relationship status, and household size, low socioeconomic index remained strongly associated with past-year IPV (odds ratio = 5.0; 95% confidence interval: 2.4, 10.7).

Conclusions

Native American women in our sample experienced exceptionally high rates of lifetime and past-year IPV. Additionally, within this low-income sample, there was strong evidence of socioeconomic variability in IPV. Further research should determine prevalence of IPV against Native American women from diverse tribes and regions, and examine pathways through which socioeconomic disadvantage may increase their IPV risk.
  相似文献   
10.
Rhizomelic chondrodysplasia punctata is a human autosomal recessive disorder characterized by skeletal, eye and brain abnormalities. The disorder is caused by mutations in the PEX7 gene, which encodes the receptor for a class of peroxisomal matrix enzymes. We describe the generation and characterization of a Pex7 mouse knockout (Pex7(-/-)). Pex7(-/-) mice are born severely hypotonic and have a growth impairment. Mortality in Pex7(-/-) mice is highest in the perinatal period although some Pex7(-/-) mice survived beyond 18 months. Biochemically Pex7(-/-) mice display the abnormalities related to a Pex7 deficiency, i.e. a severe depletion of plasmalogens, impaired alpha-oxidation of phytanic acid and impaired beta-oxidation of very-long-chain fatty acids. In the intermediate zone of the developing cerebral cortex Pex7(-/-) mice have an increase in neuronal density. In vivo neuronal birthdating revealed that Pex7(-/-) mice have a delay in neuronal migration. Analysis of bone ossification in newborn Pex7(-/-) mice revealed a defect in ossification of distal bone elements of the limbs as well as parts of the skull and vertebrae. These findings demonstrate that Pex7 knockout mice provide an important model to study the role of peroxisomal functioning in the pathogenesis of the human disorder.  相似文献   
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