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31.
Jerry  A.  Shields  Ralph  C.  Eagle  Jr  Carol  L  Shields  Brian  P.  Marr  李学民 《美国医学会眼科杂志(中文版)》2006,18(1):33-39
众所周知,视网膜星形细胞瘤常伴有结节性硬化的表现。视网膜星形细胞瘤一般是发生在视网膜神经纤维层的无蒂轻度隆起性病变。临床上可以是单侧发生,也可以是双侧发生。可以单个病灶,也可以多个病灶。可以是透明的,也可以是不透明的。可以有钙化,也可以没有钙化。视网膜星形细胞瘤相对固定的伴有眼内结节性硬化,很少表现为浸润性增长。在很少的情况下视网膜星形细胞瘤可以表现出浸润性增长,造成局部严重并发症。  相似文献   
32.
BACKGROUND: Common clinical forms of oral lichen planus (OLP) and oral lichenoid reactions (OLR) are erythematous (ERY) or reticular (RET). The purpose of this study was to find histopathological changes that differ between these forms. METHODS: Epithelial thickness, epithelial proliferation rate, apoptosis, and HLA-DR expression were compared among 10 reticular and 12 erythematous lesions, and 11 normal oral mucosa samples (NOM). RESULTS: The epithelium in ERY was thinner than in NOM, whereas RET showed values between ERY and NOM. Cell proliferation increased significantly in ERY as compared with RET and NOM, with no difference between RET and NOM. Relative numbers of epithelial cell nuclei displaying visible chromatin condensation were reduced in ERY form. CONCLUSIONS: The markedly increased cell proliferation in ERY supports the notion that this form displays a higher disease activity as compared to RET. It can therefore be important to study each disease form separately.  相似文献   
33.
BACKGROUND: A low level of response to alcohol has been associated with both the genetic constitution of the regulatory region (SLC6A4) of the human serotonin (5-hydroxytryptamine, 5-HT) transporter (5-HTT) and with future alcohol intake and an increased risk for alcoholism. To date, all studies of relevant polymorphisms have been carried out in populations in the United States. METHODS: Data were extracted from a subset (n = 243) of a cohort of children who have been observed since birth through evaluation of the family history of alcoholism and psychosocial risk influences. At age 16 years, the response to alcohol was assessed with the Self-Rating of the Effects of Alcohol (SRE) questionnaire, and the average amount of alcohol intake per month was assessed during the prior 6 months. Additional variables that were measured included the 5-HTT genotype, externalizing behavior, and sociodemographic variables, such as gender and age. RESULTS: The level of response to alcohol was significantly lower among carriers of two long alleles of the 5-HTT regulatory region compared with carriers of one or two short alleles (Mann-Whitney U = 5225.0, p = .005). In a multiple regression analysis, the level of response to alcohol and externalizing behavior but not psychosocial factors significantly predicted the average amount of alcohol intake per month. CONCLUSIONS: This study demonstrates that, independent of the assessed psychosocial variables, the 5-HTT genotype correlated with the level of response to alcohol and predicted alcohol intake among 16-year-old adolescents.  相似文献   
34.
PURPOSE: The advantages of a focometer (FOCOMETER) over other methods of refraction for use in developing countries are that it is lightweight, compact, relatively inexpensive, fairly quick, and easy to use with minimal training. This clinical trial compared the repeatability, validity, and ease of use of the focometer with an autorefractor. METHODS: The refractive status of the right eye of 80 participants was determined with an autorefractor (Canon RK3). Three measurements were also taken with the focometer. RESULTS: The spherical equivalent (M) of the focometer was 0.25 D more positive than the autorefractor (p < 0.001) and 84% of measurements were within 0.75 D of the autorefractor. The autorefractor detected astigmatism in 91% (73) of the eyes, whereas the focometer identified only 32% (26). The design of the clock target restricts cylinder axis accuracy to the nearest 15 degrees . There was evidence of a learning effect for the focometer: the second and third measurements were more repeatable in the untrained group. There were no differences between the mean (1.03 +/- 2.28) and third focometer (-1.05 +/- 2.32) measurements (p = 0.34). However, using the third focometer measurement, 94% of participants had visual acuities of at least 6/12(-2). CONCLUSIONS: This study highlighted the focometer's restricted power range, inaccuracy of astigmatism and axis determination, and dependence on subject understanding and compliance. Therefore, in most clinical settings, the focometer would not be adequate for quantifying refractive error, but the focometer spherical equivalent was within acceptable limits of the autorefractor, and the visual acuity with lenses determined by the focometer indicates its potential usefulness in public health settings, especially where only spherical ready-made spectacles are dispensed. There may be more cost-effective ways to determine refractive error in these circumstances. A potentially important enhancement in focometer methodology that improves its ease of use was identified: use only the third measurement for each eye.  相似文献   
35.
Objective: To document the breastfeeding practices of Aboriginal mothers delivering in Perth. Design and methods: A cohort of mothers was followed from the time of delivery for six months to obtain details of infant feeding practices. Subjects: A total of 455 mothers delivered during the study period and were asked to participate. A total of 425 mothers completed the initial questionnaire. Setting: The study was undertaken in six public hospitals in Perth, Western Australia. Data analyses: The data were analysed using spss . Breastfeeding duration was calculated using Kaplan–Meier survival analysis. Main outcome measures: Breastfeeding initiation and duration. Results: The mean age of the Aboriginal mothers was 21.8 years (range 14–39 years, SD 5.32) and the average gestational age was 38.3 weeks. Almost 50% of the mothers in the study delivered by Caesarean section. At discharge from hospital 89.4% (CI 86.6–92.1) of mothers were breastfeeding, declining to 58.8% (CI 53.5–64.1) at six months. When compared with non‐Aboriginal mothers, the Aboriginal breastfeeding rates were higher than the non‐Aboriginal average breastfeeding rates, but lower than the highest socioeconomic group. Conclusions: The breastfeeding rates of Aboriginal mothers are higher than for other Australians. This is despite the low maternal age and level of education and the high rates of low‐birth‐weight infants and Caesarean section among this population. The World Health Organization recommendation for infant feeding is exclusive breastfeeding until six months, but less than one‐third of Aboriginal mothers achieved this recommendation.  相似文献   
36.
Clinical versus ultrasonographic evaluation of scrotal disorders   总被引:1,自引:0,他引:1  
Clinical and ultrasonographic examinations of scrotal disorders were compared in 166 patients in order to determine their ability to distinguish between those diseases requiring surgery and those requiring clinical follow-up only. Ultrasound examinations were efficient in discriminating between normal and pathological findings. Extra-testicular lesions were readily differentiated from testicular ones. Although both clinical and ultrasonographic examinations had high sensitivity (90%) in detecting testicular cancer, the number of false positive findings was smaller after ultrasound examination. This gave a predictive value of a positive test of 53% after ultrasound examination but only 33% after clinical examination. Ultrasound examination may, therefore, reduce the number of surgical explorations in the scrotum and should be performed in patients with suspected testicular pathology based on history and palpatory findings.  相似文献   
37.
Some 50% of human cancers are associated with mutations in the core domain of the tumor suppressor p53. Many mutations are thought just to destabilize the protein. To assess this and the possibility of rescue, we have set up a system to analyze the stability of the core domain and its mutants. The use of differential scanning calorimetry or spectroscopy to measure its melting temperature leads to irreversible denaturation and aggregation and so is useful as only a qualitative guide to stability. There are excellent two-state denaturation curves on the addition of urea that may be analyzed quantitatively. One Zn2+ ion remains tightly bound in the holo-form of p53 throughout the denaturation curve. The stability of wild type is 6.0 kcal (1 kcal = 4.18 kJ)/mol at 25°C and 9.8 kcal/mol at 10°C. The oncogenic mutants R175H, C242S, R248Q, R249S, and R273H are destabilized by 3.0, 2.9, 1.9, 1.9, and 0.4 kcal/mol, respectively. Under certain denaturing conditions, the wild-type domain forms an aggregate that is relatively highly fluorescent at 340 nm on excitation at 280 nm. The destabilized mutants give this fluorescence under milder denaturation conditions.  相似文献   
38.
OBJECTIVES: Specific information addressing the management of cerebrospinal fluid (CSF) fistulas that originate from within the sphenoid sinus remains scant. The objective of this study was to review the cause and management of CSF rhinorrhea arising from the sphenoid sinus. STUDY DESIGN AND SETTING: This is a retrospective chart review of 12 cases of CSF rhinorrhea arising from the sphenoid sinus that occurred in 11 patients. All patients were treated at a single institution between 1994 and 1999. RESULTS: All patients were managed surgically with sphenoid sinus fat obliteration using an endoscopic sublabial, transseptal approach. This approach was successful for all 12 cases, with median duration of follow-up of 18 months. CONCLUSIONS: Endoscopically assisted transseptal repair of CSF fistulas that originate within the sphenoid sinus offers an alternate approach to previously described methods of repair in this region. Advantages include wide access to the entire sphenoid sinus, improved access to laterally pneumatized regions within the sphenoid sinus, and rostral mucosal closure over the repair within the sinus.  相似文献   
39.
40.
蒿甲醚引起小鼠体内日本血吸虫和曼氏血吸虫皮层变化1肖树华,沈炳贵,JackHORNER2,BrianACATTO3(中国预防医学科学院寄生虫病研究所,世界卫生组织疟疾、血吸虫病和丝虫病合作中心,上海200025,中国;2DepartmentofCli...  相似文献   
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