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101.
In this study, we evaluated the presence of human papillomavirus (HPV) DNA in organs of the female upper genital tract, using nine hysterectomy and salpingo-oophorectomy specimens affected by HPV-positive invasive cervical carcinomas, to establish if cervical HPV infection can spread to upper tracts of the female genital system. HPV DNA was evaluated by polymerase chain reaction (PCR) in all cervical carcinomas as well as in all tracts of the genital system. Then, these data were compared with the results obtained from PCR study of five other hysterectomy and salpingo-oophorectomy specimens (control cases). The criteria used for selection of the control cases were informed consent of the patients for research at the time of surgery, absence of neoplasms, absence of any anatomic lesion caused by HPV in cervix, and external genitalia. All selected cases were squamous cervical carcinomas. PCR analysis revealed HPV DNA in all cases of cervical carcinoma. The HPV DNA was detected as weak positivity on PCR analysis in other organs of the genital system. However, the distribution of HPV DNA varied in the various cases and in the different tracts of the same hysterectomy and salpingo-oophorectomy specimen. We believe that the HPV DNA, detected as a weakly positive signal, in the upper genital tract of patients who have a cervical squamous carcinoma could be a reflection of a latent HPV infection, as well as a sign of the existence of micrometastases containing HPV DNA, which cannot be detected by conventional histologic techniques.  相似文献   
102.
BACKGROUND: Rofleponide palmitate is an esterified glucocorticosteroid pro-drug with a promising pre-clinical profile designed to deliver topical airway treatment for allergic rhinitis and asthma in a novel manner. Thus, the rofleponide palmitate pro-drug is designed to provide topical exposure of the mucosa to the inactive lipophilic drug, which would be locally metabolized to the more hydrophilic and readily cleared drug rofleponide. OBJECTIVE: To examine whether rofleponide palmitate affects nasal symptoms and peak inspiratory flow (PIF) in a pollen-season model of allergic rhinitis and to compare any such effects with those of another glucocorticosteroid (i.e., budesonide). METHODS: During the pollen-free season, 40 patients with strictly seasonal allergic rhinitis received topical nasal spray treatment with an aqueous solution of rofleponide palmitate 400 microg and an aqueous solution of budesonide 128 microg once daily for 10 days in a double-blind, placebo-controlled, and crossover study. After 3 days of drug treatment, individualized allergen challenges were given once daily for 7 days while the treatment continued. The washout periods between each of the challenge series were 2 weeks. Nasal symptoms and PIF were recorded in the morning and evening, as well as 10 and 20 min after each allergen challenge. The mean recordings obtained during the last 3 days of the allergen-challenge series, when symptoms were established and when the treatment had lasted for 8-10 days, were used in the analysis. RESULTS: Both active treatments reduced nasal symptoms and improved nasal PIF compared with placebo (P<0.01-0.001). There was no overall difference in efficacy between rofleponide palmitate 400 microg and budesonide 128 microg. CONCLUSIONS: Topical treatment with aqueous solutions of rofleponide palmitate attenuates nasal symptoms and improves nasal PIF in allergic rhinitis. The overall efficacy of 400 microg of rofleponide palmitate is similar to that of 128 microg of budesonide in the pollen-season model used in this study.  相似文献   
103.
目的 :为满足基因治疗的需要构建人白细胞介素 12 (hIL 12 )双亚基共表达质粒。方法 :先从人胚肾组织的逆转录产物中用PCR方法扩增出它的两个亚基P4 0 和P3 5的cDNA全长 ,分别克隆入真核表达载体pcDNA3.1(+/ )中构建单亚基质粒———P(+) /P4 0 和P( ) /P3 5,然后再将二者串联克隆入真核表达载体 pcDNA3.1(+)中得到P(+) /IL 12质粒。脂质体转染HepG2后 2 4,48hELISA检测细胞培养上清内hIL 12蛋白质表达。结果 :P(+) /IL 12质粒经酶切和测序证明两亚基连接方向正确 ,序列无突变 ;ELISA检测细胞上清结果证实可表达hIL 12蛋白质。结论 :成功构建P4 0 和P3 5双亚基真核共表达质粒———P(+) /IL 12 ,为模拟hIL 12生理表达方式 ,简化hIL 12基因治疗操作奠定了基础。  相似文献   
104.
Invasion of human immunodeficiency virus (HIV) into the central and peripheral nervous system produces a wide range of neurological symptoms, which continue to persist even with adequate therapeutic suppression of the systemic viremia. The development of therapies designed to prevent the neurological complications of HIV require a detailed understanding of the mechanisms of virus penetration into the nervous system, infection, and subsequent neuropathogenesis. These processes, however, are difficult to study in humans. The identification of animal lentiviruses similar to HIV has provided useful models of HIV infection that have greatly facilitated these efforts. This review summarizes contributions made from in vitro and in vivo studies on the infectious and pathological interactions of feline immunodeficiency virus (FIV) with the nervous system. In vivo studies on FIV have provided insights into the natural progression of CNS disease as well as the contribution of various risk factors. In vitro studies have contributed to our understanding of immune cell trafficking, CNS infection and neuropathogenesis. Together, these studies have made unique contributions to our understanding of (1) lentiviral interactions at the blood–cerebrospinal fluid (CSF) barrier within the choroid plexus, (2) early FIV invasion and pathogenesis in the brain, and (3) lentiviral effects on intracellular calcium deregulation and neuronal dysfunction. The ability to combine in vitro and in vivo studies on FIV offers enormous potential to explore neuropathogenic mechanisms and generate information necessary for the development of effective therapeutic interventions.  相似文献   
105.
106.
This study investigated the effects of neurokinin A (NKA) on cholinergic neural responses in human bronchus. NKA (0.1 nM) did not alter the contractile response to submaximal electrical field stimulation. However, K+ channel blockade with 4-aminopyridine (4-AP) (0.1 mM) potentiated the response to electrical field stimulation (to 182 ± 25% of control, n = 4, P < 0.05) and subsequent addition of NKA in the presence of 4-AP produced further potentiation (to 123 ± 6% of the response to 4-AP n = 4, P < 0.05). Neither 4-AP (0.01 or 0.1 mM) nor NKA in the presence of 4-AP potentiated the actions of exogenous acetylcholine but in these experiments 4-AP itself produced a marked direct contractile response. Thus NKA in the presence of K+ channel blockade potentiates cholinergic neural response in human bronchus and this occurs at a prejunctional site.  相似文献   
107.
Abstract Substance P is a neuropeptide which is present in peripheral C nerve endings and released from them. Free nerve endings of C nerve are present in human epidermis. The effects of substance P on the transmembrane signaling system of pig epidermal sheets were previously reported. In these studies, a small amount of cells other than keratinocytes contaminated the epidermal sheets and the species difference from human was also noticed. Therefore we investigated the effects of substance P on cultured normal human epidermal keratinocytes. Alteration of intracellular free calcium (Ca2+) in single living keratinocytes was studied using an inverted fluorescence microscope and Ca2+ -sensitive dye, Fura 2-AM. Treatment of normal human epidermal kertinocytes with substance P resulted in an increase in inositol 1,4,5-trisphosphate and in intracellular Ca2+. Substance P inhibited DNA synthesis of the keratinocytes in a dose-dependent manner. These results are consistent with the view that substance P stimulates phosphatidylinositol-4,5-bisphosphate hydrolysis of human keratinocytes, resulting in inositol 1,4,5-trisphosphate-Ca2+ signal.  相似文献   
108.
Movement-related neuromagnetic fields from eight healthy human subjects were investigated in a Bereitschaftspotential paradigm. The three conditions studied were right-sided mouth, index finger and foot movement. The neuromagnetic field patterns corresponding to the motor field and the movement-evoked field I were analysed using a moving dipole model. For both components a somatotopic organization was found: the estimated dipole locations for the mouth were more lateral and those for the foot more medial than the estimated dipole positions for the index finger movement. With regard to possible clinical applications, e.g. non-invasive mapping of the sensorimotor cortex and studies of plasticity of the motor function, the present results suggest that the investigation of movement-evoked field I for the index finger condition is most likely to yield further results.  相似文献   
109.
The use of a visual aid to check anaesthetic machines   总被引:1,自引:0,他引:1  
J. GROVES  N. EDWARDS  B. CARR 《Anaesthesia》1994,49(2):122-125
  相似文献   
110.
We present the new computerized Human Brain Atlas (HBA) for anatomical and functional mapping studies of the human brain. The HBA is based on many high-resolution magnetic resonance images of normal subjects and provides continuous updating of the mean shape and position of anatomical structures of the human brain. The structures are transformable by linear and nonlinear global and local transformations applied anywhere in 3-D pictures to fit the anatomical structures of individual brains, which, by reformatting, are transformed into a high-resolution standard anatomical format. The power of the HBA to reduce anatomical variations was evaluated on a randomized selection of anatomical landmarks in brains of 27 young normal male volunteers who were different from those on whom the standard brain was selected. The HBA, even when based only on standard brain surface and central structures, reduced interindividual anatomical variance to the level of the variance in structure position between the right and left hemisphere in individual brains. © 1994 Wiley-Liss, Inc.  相似文献   
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