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51.
Contact dermatitis in patients with leg ulcers   总被引:3,自引:2,他引:1  
100 patients with leg ulcers were patch tested against a standard battery of allergens. The readings were carried out daily from the 2nd to the 7th days. 55 patients showed positive reactions to one or more allergens. 32% of positive reactions developed for the first time after 48 h and 11% after 72 h. No single day or combination of two days gave 100% positive results. A single reading on the 4th day gave the highest number of positive reactions at 92%. The prevalence of positive patch tests was significantly higher in patients with surrounding eczema, and in patients with positive patch tests the ulcer duration was significantly longer than in those with negative patch tests. The total number of positive results in individuals increased linearly with the duration of the ulcer. Of allergens to which the ulcer was exposed, the occurrence of multiple sensitivity was significantly greater than predicted from the prevalence of individual sensitivities. However, there was no association between medicaments and metal sensitivity. This, together with the absence of an exponential rise in the number of allergens with the duration of ulcer, does not support the theory of systemic ampliative allergy.  相似文献   
52.
To study the phenotypic specificity of S-100 beta and insulin-like growth factor II (IGF-II) for developing monoamine neurons, serotonin (5-HT) neurons from the embryonic day 14 (E14) rostral raphe or dopamine (TH) neurons from the substantia nigra/ventral tegmental area were cultured for 3 days in vitro (3 DIV) in the presence of these factors. Neuronotrophic effects were analyzed by computer-assisted morphometry of 5-HT and TH-immunoreactive neurons. S-100 beta and IGF-II differentially regulated the growth of 5-HT and TH neurons but did not affect their survival. S-100 beta significantly increased several parameters of neurite outgrowth by 5-HT neurons but inhibited the spatial extent (field area) of TH neurites. IGF-II promoted growth of cell bodies of both phenotype, but only stimulated neurite outgrowth by TH neurons. S-100 beta and IGF-II differentially affected the number of GFAP immunoreactive cells from raphe and substantia nigra, but these effects did not correlate with the specificity of neuronotrophic effects. S-100 beta and IGF-II immunoreactivities were expressed in glial cultures derived from the same brain regions, raising the possibility that these factors have autocrine effects on glia as well as paracrine actions on neurons. The results of this study suggest that specificity of neurotrophic factors for particular embryonic neurons may be correlated with their neurotransmitter phenotype.  相似文献   
53.
目的 探讨神经生长因子 (NGF)对小脑皮质神经细胞凋亡的影响 ,为临床治疗小脑变性疾病提供新的措施。方法 以原代培养的新生SD乳鼠小脑皮质细胞建立谷氨酸诱导的神经细胞凋亡模型。为观察NGF对受损细胞的保护作用 ,应用MTT法测定细胞的存活率和细胞代谢情况 ;利用光学显微镜技术观察细胞凋亡的形态学改变。结果 Glu (5 0 0 μmol/L)作用 5min可诱导小脑神经细胞凋亡。MTT法计数结果显示 ,NGF高剂量治疗组细胞存活率显著高于模型组 (P <0 0 1) ,光学显微镜观察发现受损细胞的形态学变化也得到明显改善。结论 外源性NGF能够减轻大鼠小脑皮质神经细胞凋亡。  相似文献   
54.
Generation and survival of midbrain dopaminergic (DA) neurons were investigated using tyrosine hydroxylase (TH) immunocytochemistry combined with tritiated thymidine autoradiography at appropriate anatomical levels throughout the anteroposterior (A/P) axes of the substantia nigra pars compacta (SNc) and the ventral tegmental area (VTA). The wild-type (+/+) and homozygous weaver (wv/wv) mice used here were the offspring of pregnant dams injected with the radioactive precursor when the mesencephalic neurons were being produced (gestational days 11-15). Data reveal that, at postnatal day 90, depletion of TH-stained cells in the wv/wv presented an A/P pattern of increasing severity and, therefore, the DA cells located in posterior parts of the SNc or the VTA appear to be more vulnerable than the settled anterior neurons. When the time of neuron origin is inferred for each level of these cell groups, it is found that the neurogenesis span is similar for both experimental groups, although significant deficits in the frequency of wv/wv late-generated neurons were observed in any level considered. On the other hand, it has been found that TH-positive neurons were settled along the extent of the SNc and the VTA following precise and differential neurogenetic gradients. Thus, the acute rostrocaudal increase in the proportion of late-generated neurons detected in both+/+DA-cell groups is disturbed in the weaver homozygotes due to the indicated A/P depletion.  相似文献   
55.
BACKGROUND: Seborrhoeic dermatitis (SD) is a common dermatosis in human immunodeficiency virus (HIV)-positive patients, many of whom do not respond satisfactorily to conventional topical treatments such as corticosteroids and antifungals. OBJECTIVE: A pilot study to investigate the efficacy and tolerability of pimecrolimus cream 1% in HIV-positive patients with facial SD. METHODS: In a single-centre study, 21 HIV-infected patients with mild to severe SD were treated twice daily with pimecrolimus cream 1% for 14 days. Thereafter, treatment was discontinued and patients followed up for 5 weeks. Skin involvement at baseline and on days 7, 14, 21, 35 and 49 was assessed using a four-point clinical score and digital photography. MAIN OUTCOME MEASURES: Efficacy and safety of pimecrolimus cream 1% treatment and incidence of relapse in the follow-up phase. Results Marked improvement was seen in clinical parameters at day 7, with >or= 90% patients clear of symptoms at day 14. Relapse was observed at day 35 but signs were milder than at baseline. All patients responded to therapy, despite their immunological status. Pimecrolimus did not alter CD4(+) and CD8(+) T-cell counts or viral load during the treatment period. CONCLUSION: Pimecrolimus cream represents a new, effective therapeutic option for facial SD in HIV patients.  相似文献   
56.
We present a case of lung cancer that showed false positive accumulation in an 18F fluorodeoxyglucose positron emission tomography (FDG-PET) scan following induction chemotherapy for suspected metastasis and progression of malignancy. A 66-year-old man was diagnosed with squamous cell carcinoma in the lung, classified as clinical stage IIIA (T2N2M0), and underwent induction chemotherapy. An FDG-PET scan prior to chemotherapy demonstrated accumulation only in the tumor, whereas following treatment it revealed a strong accumulation not only in the tumor, but also in the supraclavicular lymph nodes, which indicated lymph node metastasis. The patient underwent a biopsy of the right supraclavicular lymph node and mediastinoscopy, after which all dissected lymph nodes showed sarcoid reactions and no tumor cells were found pathologically. We concluded that when evaluating the effect of induction chemotherapy for malignancy, a sarcoid reaction might lead to the false positive accumulation of FDG.  相似文献   
57.
58.
Objective   This randomized control trial examined the effects of a short-term, interaction-focused and attachment-based video-feedback intervention (VIPP: video-feedback intervention to promote positive parenting).
Design   VIPP effect on mothers' sensitive responsiveness and infant–mother attachment security was evaluated in a sample ( n  = 54) of low sensitive, non-clinical, middle class Lithuanian mothers.
Methods   Maternal sensitivity was assessed in a free play session with the Ainsworth's sensitivity scale, and attachment security was observed using the Attachment Q sort for home observations.
Results   We found that the intervention mothers indeed significantly improved their sensitive responsiveness through participation in our VIPP. The effect size was large according to Cohen's criteria, d  = 0.78. VIPP enhanced maternal sensitive responsiveness even when maternal age, educational level, depression, daily hassles, efficacy, infant gender, and infant negative and positive affect were controlled for. However, attachment security in the VIPP infants was not enhanced after the intervention, compared with the control infants, and the infants did not seem to be differentially susceptible to the increase in maternal sensitivity dependent on their temperamental reactivity.
Conclusion   We suggest that a relatively brief and low-cost programme can provide effective support for mothers who lack sensitivity in the interactions with their infants.  相似文献   
59.
分析了92例胸膜活检资料,认为其阳性率与下述因素有关:疾病种类、病例选择、活检器械、取材方法及技术、重复检查、临床医师与病理医师的配合。  相似文献   
60.
阻塞性睡眠呼吸暂停综合征的临床研究   总被引:4,自引:0,他引:4  
强调对阻塞性睡眠呼吸暂停综合征的认识,以达到对该病的早期诊与治疗。方法应用Autoset诊疗系统及鼻持续正压通气治疗仪,对66例OSAS患者进行确诊及序贯治疗。  相似文献   
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