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61.
This study aimed to evaluate stallion sperm survival after 24 h of cooled storage in the presence of seminal plasma (SP) derived from the sperm‐rich fractions (SRF) or sperm‐poor fractions(SPF) of the ejaculate, without SP, or in the presence of SP from other stallions. Ejaculates were collected from four stallions using an automated phantom, which separated the semen into five cups. Centrifuged and washed spermatozoa from cup 2 (SRF) were mixed with skim milk extender to a concentration of 100 × 106 sperm/ml and then 1:1 (v/v) with SP from the stallion's own or another stallions’ second (SP‐SRF) or last cup (SP‐SPF). Skim milk extender (K) and skim milk extender supplemented with modified Tyrode's medium (KMT) were used as control treatments. After a 24‐h storage period in a transport container, spermatozoa were evaluated for motion characteristics and plasma membrane integrity by calcein acetoxymethyl (AM)/propidium iodide staining. The percentage of spermatozoa with intact plasma membranes after storage was lower in SP‐SRF than in SP‐SPF, and the highest in K (P < 0.05). Progressive motility (PMOT) was lower for sperm stored in SP‐SRF than for sperm stored in SP‐SPF (P < 0.05), but there was no significant difference in total motility (TMOT). Sperm stored in KMT (P < 0.05) registered the highest TMOT and PMOT percentages. Osmolarity was significantly higher and pH lower in K than in KMT or SP. Treatment with SP‐SPF from three stallions benefited the PMOT of sperm from one stallion. These preliminary findings suggest that SP from SRFs may be more harmful during storage than SP from SPFs. Removal of SP improves sperm survival in KMT extender, and exchanging SP between stallions seems to influence sperm survival.  相似文献   
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Population-based studies report that children with epilepsy have relatively better prognosis than those with an onset at infancy, though studies about this period are limited. We aimed to evaluate the etiology in infant epilepsy less than 2 years of age and foreseeable risk factors for anti-epileptic drug resistance. We evaluated the patients who were presented to the division of pediatric neurology in our university hospital with seizures when they were between 1 and 24 months of age and diagnosed as epilepsy. Two hundred and twenty-nine patients (110 male and 119 female) who were diagnosed between the ages of 1–24 months were included in the study. The etiologies were structural (n = 55;24%), genetic (n = 29;12.7%), metabolic (n = 27;11.7%), and infectious (n = 8;3.5%), and it was unknown in 110 patients (48%). One-hundred and forty (61%) patients met the criteria for drug-resistant epilepsy (DRE). Multivariate logistic regression analysis showed that developmental delay at onset (OR 3.9, 95% CI 1.22, 12.47, p = 0.021), multifocal epileptiform discharges (OR 2.8, 95% CI 1.1, 7.44, p = 0.031), and history of status epilepticus (OR 32.9, 95% CI 3.8, 285.35, p = 0.001) were strong predictive factors for DRE. The epilepsy in children under 2 years of age is highly resistant to the anti-epileptic drugs, which could be related to the history of status epilepticus, developmental delay at onset, and multifocal epileptiform discharges.  相似文献   
64.
Background Typical hypomimia develops in almost all Parkinson’s disease (PD) patients. We observed the presence of hemihypomimia (HH) in some of our PD patients. Objective To discern the presence of hemihypomimia, to compare clinical features of these patients with the patients without HH and then to evaluate HH prospectively. Methods Among 353 patients with PD followed-up between September 2003 and December 2004, 204 patients in stage 2 of Hoehn-Yahr were evaluated and hemihypomimia was observed in 13 PD patients (6.4%). Two groups were compared with respect to the age of onset of the first PD symptom, duration of PD and the body side affected predominantly. In addition, persistence of HH was prospectively evaluated in 11 of 13 patients with HH up to two-year-follow up period. Results Hemihypomimia was interestingly on the right side of the face in all patients. Of these 13 HH patients, all but one had predominantly right-sided PD symptomatology. In the comparison of HH patients with the remaining group (n = 191), patients with HH had significantly earlier onset of PD symptoms (mean: 53.9 vs 58.5 years), and shorter PD duration (mean: 4.0 vs 6.2 years) (p < 0.01). Up to two-year-follow up, hemihypomimia, which was not changed by several triggered emotional facial expressions, clinically persisted. Conclusion Our observations suggest that hemihypomimia is a rare phenomenon in PD, especially in PD patients having early-onset and shorter PD duration which may persist for several years in concordance with typical asymmetrical involvement of the limbs. HH developed in the right side, prominently on the lower part of the face. Understanding the underlying mechanism(s) about how hemihypomimia appears, and why it dominantly affects the right side of the face deserves further assessment. Received in revised form: 23 April 2006  相似文献   
65.
Abstract   Acute isolated neurological syndromes, such as optic neuropathy or transverse myelopathy, may cause diagnostic problems since they can be the first presentations of a number of diseases such as multiple sclerosis (MS) and collageneous tissue disorders. In the present study, particular systemic lupus erythematosus (SLE) and primary Sjogren syndrome (pSS) patients, who were followed up with the initial diagnosis of possible MS with no evidence of collagen tissue disorders for several years, are described. Five patients with the final diagnosis of SLE and five pSS patients are evaluated with their neurologic, systemic and radiologic findings. Over several years, all developed some systemic symptoms like arthritis, arthralgia, headache, dry mouth and eyes unexpected in MS. During the regular and close follow-up laboratory evaluations of vasculitic markers revealed positivity, leading to the final definite diagnosis of SLE or pSS. Patients with atypical neurological presentation of MS, a relapsing remitting clinical profile, or lack of response to the regular MS treatment should be evaluated for the presence of a connective tissue disease. Various laboratory tests, such as cerebrospinal fluid findings, autoantibodies profile, markers, cranial and spinal magnetic resonance imaging, can be helpful for the differential diagnosis. Lack of response to the regular multiple sclerosis treatment, even increasing rate of relapses can force the clinician for the differential diagnosis. In particular cases an accurate diagnosis can only be made after close follow-up.  相似文献   
66.
Sex is a biological variable that contributes to individual variability in brain structure and behavior. Neuroimaging studies of population-based samples have identified normative differences in brain structure between males and females, many of which are exacerbated in psychiatric and neurological conditions. Still, sex differences in MRI outcomes are understudied, particularly in clinical samples with known sex differences in disease risk, prevalence, and expression of clinical symptoms. Here we review the existing literature on sex differences in adult brain structure in normative samples and in 14 distinct psychiatric and neurological disorders. We discuss commonalities and sources of variance in study designs, analysis procedures, disease subtype effects, and the impact of these factors on MRI interpretation. Lastly, we identify key problems in the neuroimaging literature on sex differences and offer potential recommendations to address current barriers and optimize rigor and reproducibility. In particular, we emphasize the importance of large-scale neuroimaging initiatives such as the Enhancing NeuroImaging Genetics through Meta-Analyses consortium, the UK Biobank, Human Connectome Project, and others to provide unprecedented power to evaluate sex-specific phenotypes in major brain diseases.  相似文献   
67.

Objective

We aimed to analyze the development of epilepsy in a patient group with periventricular leukomalacia followed at a tertiary pediatric neurology center.

Patients and methods

The study included 108 children aged between 2 and 8 years with radiologically proven periventricular leukomalacia who had been regularly observed at the Istanbul University, Istanbul Faculty of Medicine, Department of Pediatrics, Pediatric Neurology outpatient clinic between January 2006 and December 2011.

Results

Neonatal seizures were reported in 22 patients (20.3%), 14 of whom developed epilepsy. A significant correlation was found between neonatal seizures and prematurity and newborn asphyxia (p = 0.013 and p = 0.010, respectively). Epilepsy developed in 35 patients (32.4%), history of neonatal seizures and more severe loss of white matter, periventricular hyperintensity and corpus callosum involvement were found to be correlated with epilepsy (p = 0.001, p = 0.004, p = 0.016, and p = 0.004, respectively). The most common seizure pattern observed was generalized tonic clonic seizures (n = 13) and complex partial seizures (n = 11). Those with focal EEG findings had a significantly better neurodevelopmental and cognitive level than those with multifocal/generalized EEG findings (p = 0.024). Seizures continued with varying frequency in 14 epileptic patients (40%) despite antiepileptic treatment.

Conclusion

Almost a third of patients with periventricular leukomalacia develop epilepsy that can be intractable in substantial part. Neonatal seizures and severe MRI findings are important clues that can indicate the development of epilepsy in these patients.  相似文献   
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70.
Safiye G    ü    Meral Top  u    rkan Kü    ü  kali  Zuhal Ak    ren  Izzet Berkel  Figen Ersoy  Meral Gü  nay  I  il Saat  i 《Fetal and pediatric pathology》1995,15(2):309-319
The clinical features of three children with Griscelli syndrome and autopsy findings of two are presented. The patients were 5 years, 9 months, and 3 months old, respectively. Clinical features included partial albinism, hepatosplenomegaly, and various neurological symptoms. Light and electron microscopic studies of the skin were compatible with Griscelli syndrome. Postmortem examination of the viscera and central nervous system revealed lymphohistiocytic infiltration with erythrophagocytosis. Bilateral diffuse involvement of the central nervous system, cranial nerve, and spinal cord was detected in both cases.  相似文献   
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