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91.
Sphingolipids, glycosylphosphatidylinositol (GPI)-anchored proteins, and certain signaling molecules segregate from bulk membrane lipids into lateral domains termed lipid rafts, which are often isolated based on their insolubility in cold nonionic detergents. During immunohistological studies of gangliosides, major sphingolipids of the brain, we found that cold Triton X-100 solubility is bidirectional, leading to histological redistribution from gray to white matter. When brain sections were treated with > or =0.25% Triton X-100 at 4 degrees C, ganglioside GD1a, which is normally enriched in gray matter and depleted in white matter, redistributed into white matter tracts. Incubation of brain sections from knockout mice lacking GD1a with wild-type sections in the presence of cold Triton X-100 resulted in GD1a redistribution from wild-type gray matter to knockout white matter. GM1, which is normally enriched in white matter, remained in white matter after cold detergent treatment and did not migrate to knockout mouse brain sections. However, when gray matter gangliosides were enzymatically converted into GM1 in situ, the newly formed GM1 transmigrated to knockout mouse brain sections in the presence of cold detergent. When purified GD1a was added to knockout mouse brain sections in the presence of cold Triton X-100, it preferentially incorporated into white matter tracts. These data demonstrate that brain white matter is a sink for gangliosides, which redistribute from gray matter in the presence of low concentrations of cold Triton X-100. A GPI-anchored protein, Thy-1, also transmigrated from wild-type to Thy-1 knockout mouse brain sections in the presence of detergent at 4 degrees C, although less efficiently than did gangliosides. These data raise technical challenges for using nonionic detergents in certain histological protocols and for isolation of lipid rafts from brain tissue.  相似文献   
92.
The activity of large dorsomedial protocerebral A2' neurosecretory neurons were investigated in late pupae of Tenebrio molitor L, which were exposed to a static magnetic field of 320 mT. Experimental groups were C: the control group which was kept at 5 meters from the magnet; CMF: pupae which were reared in control conditions and sacrificed on the eighth day of pupal stage (parents were kept in a magnetic field); and MF: pupae kept in a permanent magnetic field for eight days. Our results indicate the effects of a static magnetic field on the cytological characteristics and activity of large A2' neurosecretory neurons of Tenebrio molitor pupae.  相似文献   
93.
Aging of the population is a growing problem in all developed societies. The older people need more health and social services, and their life quality in there is getting more and more important. The study aimed at determining the characteristics of non-verbal communication of the older people living in old people's homes (OPH). The sample consisted of 267 residents of the OPH, aged 65-96 years, and 267 caregivers from randomly selected twenty-seven OPH. Three types of non-verbal communication were observed and analysed using univariate and multivariate statistical methods. In face expressions and head movements about 75% older people looked at the eyes of their caregivers, and about 60% were looking around, while laughing or pressing the lips together was rarely noticed. The differences between genders were not statistically significant while statistically significant differences among different age groups was observed in dropping the eyes (p = 0.004) and smiling (0.008). In hand gestures and trunk movements, majority of older people most often moved forwards and clenched fingers, while most rarely they stroked and caressed their caregivers. The differences between genders were statistically significant in leaning on the table (p = 0.001), and changing the position on the chair (0.013). Statistically significant differences among age groups were registered in leaning forwards (p = 0.006) and pointing to the others (p = 0.036). In different modes of speaking and paralinguistic signs almost 75% older people spoke normally, about 70% kept silent, while they rarely quarrelled. The differences between genders were not statistically significant while statistically significant differences among age groups was observed in persuasive speaking (p = 0.007). The present study showed that older people in OPH in Slovenia communicated significantly less frequently with hand gestures and trunk movements than with face expressions and head movements or different modes of speaking and paralinguistic signs. The caregivers should be aware of this and pay a lot of attention to these two groups of non-verbal expressions. Their importance should be constantly emphasized during the educational process of all kinds of health-care professionals as well.  相似文献   
94.
We are presenting a case of isolated fulminant meningococcal sepsis with two and a half year old child. Initial symptoms were obscure and common to many medical conditions, but also previously described as symptoms of meningococcal sepsis. Unrecognizing the seriousness of the condition child died at home, within few hours after examination and discharge from the hospital. Autopsy and microbiological findings unquestionably proved that the child died from septic shock caused by fulminant meningococcal sepsis.  相似文献   
95.
The pathogenesis of recurrent urinary tract infections (UTIs) in preschool children with anatomically correct urinary tract (UT) is rather obscure. In girls, the bladder wall changes of cystitis cystica (CC) may be per se responsible for UTIs recurrence. During the 20-year period, 127 preschool children (125 girls; median age: 6.1 years) with CC, in whom UT anomalies were excluded, were diagnosed. The mean duration of UTIs symptoms prior to diagnosis was 3.31 +/- 2.51 years. Cystoscopical findings were labelled as mild, moderate and severe in 22.8%, 39.4% and 37.8% of patients, respectively. Following the confirmation of CC, long-term chemoprophylaxis with sulfamethoxazole-trimethoprim/nitrofurantoin was administered. A one year UTI-free period after chemoprophylaxis discontinuation was defined as therapeutic success. With 2.5 years median duration of regular chemoprophylaxis this goal was achieved in 58 children mainly with mild/ moderate CC. Thirty children from "improved/unchanged" group taking regular prophylaxis had significant reduction of UTIs ("improved"). Only 12 children belonging to the same group taking regular prophylaxis and all children with irregular prophylaxis had approximately the same number of UTIs as before treatment ("unchanged"). The "improved/unchanged" outcomes were predominantly found in children with severe form of CC. Although urodynamic disturbances detected in more than 50% of patients in whom urodynamics was performed were not found influential on the disease outcome, they could be responsible for its development. The results of our study suggest that regular and long-lasting chemoprophylaxis remains a basis for successful treatment for majority of patients with CC, even those with severe forms. If not treated properly with chemoprophylactic agents and without fair compliance in taking drugs, the disease is prone to recurrent UTIs.  相似文献   
96.
Patients who are already diagnosed with cutaneous melanoma are at increased risk of developing another primary melanoma. The occurrence of multiple primary melanoma is a rare phenomenon, varying in frequency, with an estimated incidence ranging from 0.2% to 8.6%. The authors are presenting data on the patients with multiple primary melanoma from the Croatian Referral Melanoma Centre. The clinical, histological and epidemiological characteristics of 36 (3.6%) patients, identified from 991 patients with histologically confirmed melanoma, are analyzed in this study. Twenty-eight of the patients (78%) had two primary melanomas, six had three melanomas (16.7%) and two (5,6%) had four melanomas. Diagnosis was established synchronously in 11 patients (30%) and, in the rest of the patients, time interval between the diagnosis of the first and second melanoma varied from 1 month to the longest interval of 16 years. However, the majority of subsequent melanomas were removed within 2 years of the initial operation. The mean Breslow's thickness of the first melanoma was significantly higher than the mean Breslow's thickness of the second primary melanoma. The proportion of in situ to invasive melanomas was greater for the second melanomas compared with the first melanomas. Therefore, we emphasize the importance of regular follow-up as well as the education in regular self--skin examinations in melanoma patients in order to detect subsequent primary melanomas in the early phase.  相似文献   
97.
The loss of the corneal endothelial cells, especially in a first postoperative year, has been observed in patients who underwent penetrating keratoplasty (PK). The implantation of new generation of "iris claw" phakic IOL (Verisyse) in refractive cases has been shown to cause clinicaly insignificant endothelial cell loss. In our prospective case series we investigated the endothelial cell loss and clinical outcome in patients that either underwent PK and implantation of PCIOL or PK and implantation of Verisyse IOL. In the first group of 9 patients scheduled for PK, implantation of Verisyse was performed due to the absence of the posterior capsule support. 2 of these patients had angle supported ACIOL, 4 patients were aphakic and 3 had posttraumatic cataract with ruptured posterior capsule. The second group of 12 patients had standard "triple" procedure (PK + ECCE + PCIOL). BCVA of both groups of patients prior the operation was hand movement in 12 patients, light perception in 7 patients and 0.05 in 3 patients. The preoperative endothelial cell count of the donor grafts obtained from the eye bank was 2800 cells/mm2 on average. The follow up was 6-10 months. Six months after the operation all "Verysise" patients maintained transparent graft. Postoperative visual acuity improvement was recorded in 18 out of 21 eyes (85.7%). Best spectacle corrected visual acuity of > or = 0.3 was achived in 55.5% in the Verisyse group and in 50.0% of "triple procedure" group. The endothelial cell count and morphology were estimated on the specular microscope on a monthly basis. Mean endothelial cells loss in patients with PK and Verysise was 40 +/- 8% and in patients with "triple" procedure was 42 +/- 12% at 10 postoperative months. There was no significant difference in the endothelial cell loss and clinical outcome between the group of patients who had PK and Verysise as compared to those with implanted PCIOL.  相似文献   
98.
Skin cancer incidence in Croatia is steadily increasing in spite of public and governmental permanently measurements. It is clear that will soon become a major public health problem. The primary cause of skin cancer is believed to be a long exposure to solar ultraviolet (UV) radiation. The future designers of UV protective materials should be able to block totally the ultraviolet radiation. The aim of this paper is to present results of measurements concerning UV protecting ability of garments and sun-screening textiles using transmission spectrophotometer Cary 50 Solarscreen (Varian) according to AS/NZS 4399:1996; to show that standard clothing materials are not always adequate to prevent effect of UV radiation to the human skin; and to suggest the possibilities for its improvement for this purpose.  相似文献   
99.
Lentigo maligna melanoma (LMM) is a slowly growing tumor of elderly white population. It typically develops on chronically sun-exposed skin of the head and neck area which indicates that the cumulative exposure to the UV radiation has crucial role in the development of LMM. Precursor lesion is lentigo maligna (LM) which commonly presents as an irregular brownish pigmented macular lesion persisting for years. Women are affected more often as men by LMM, with the average age of over 60 years. The age of onset has dropped over the past years and this tumour is nowadays also diagnosed in 40-year-old individuals. However, the incidence rate increases with age and peaks in the seventh and eighth decades of life. The prognosis for invasive lentigo maligna melanoma does not differ from that for other histogenetic types of melanoma after controlling for tumour thickness. The diagnosis and treatment of LMM remain challenging. In this presentation, we review the epidemiology, clinical presentation, histopathology, and treatment of LMM.  相似文献   
100.
There is a well-established role for reactive oxygen and nitrogen species, chronic inflammation and immune response in the pathogenesis of breast cancer. Complex interactions between breast cancer cells and surrounding blood vessels are prerequisites for cancer growth and invasion. Reports in the literature concerning the systemic response to, and the effect of, common breast cancer therapy on NF-kappaB and antioxidative defence enzyme expression and activity under clinical conditions are scarce. We determined these parameters in whole blood cell lysate from 16 women with breast cancer before and after combined (cyclophosphamide, doxorubicin, 5-fluorouracil; CAF) therapy and compared the results with 16 healthy women. Significantly higher levels of NF-kappaB and Mn-SOD (both their protein level and their activity) were found in breast cancer patients before and after CAF therapy, in comparison with healthy women. In parallel measurements, no change in the level or activity of catalase (CAT) was detected. According to our findings, it appears that breast cancer creates conditions that increase the level of hydrogen peroxide in the circulating cells and that the applied CAF therapy fails to compensate, therefore creating systemic conditions that favour survival and invasion of breast cancer cells.  相似文献   
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