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51.
52.
Vitellogenesis in two spathebothriidean tapeworms, dixenous adult Cyathocephalus truncatus and monoxenous progenetic Diplocotyle olrikii, has been examined using transmission electron microscopy and cytochemical staining with periodic acid-thiosemicarbazide-silver proteinate for glycogen. Each vitelline follicle consists of vitellocytes at various stages of development and one irregularly shaped interstitial cell. Projections of the interstitial cell enclose the vitellocytes and extend as a cytoplasmic sheath on the follicular periphery. An outer thin fibrous layer (= extracellular lamina) covers the cytoplasmic sheath in C. truncatus, but lacks in D. olrikii. Maturing and mature vitellocytes contain vitelline material in the form of single small shell globules that gradually fuse and give rise to the large shell globule clusters. Morphology of shell globule clusters differs slightly in both species. In addition, single lamellar granules are present in the cytoplasm of vitellocytes of C. truncatus, but not in D. olrikii. Both electron lucent and electron dense lipid droplets are present in the vitellocytes of C. truncatus, whereas only electron dense lipids occur in D. olrikii. A single lipid droplet turns up occasionally in the nuclei of some of the vitellocytes of C. truncatus. The ultrastructural features of vitellogenesis in spathebothriideans resemble those reported previously in lower cestodes, especially in pseudophyllideans. 相似文献
53.
Tivis LJ Richardson MD Peddi E Arjmandi B 《Progress in neuro-psychopharmacology & biological psychiatry》2005,29(5):727-732
OBJECTIVE: The authors investigated saliva as a potentially reliable medium for estradiol (E2) measurements in postmenopausal women. The goal of this study was to determine whether or not saliva could be used in studies of postmenopausal women in place of serum samples. Specifically, the authors wondered whether or not saliva and serum E2, obtained simultaneously from samples collected from postmenopausal women, would correlate. DESIGN: Samples of saliva and serum were collected simultaneously from 43 postmenopausal women. 31 were regular users of estrogen therapy (ET), 12 used no ET. Pearson's correlation coefficients were conducted to determine the degree of relationship between saliva and serum samples among ET users and non-users. RESULTS: Among ET users saliva and serum E2 levels were significantly and positively correlated (r = 0.81, p < 0.0001). The two E2 values were not significantly correlated among ET non-users (r = 0.32, p < 0.31). CONCLUSIONS: These data suggest that saliva E2 may be a fairly robust predictor of serum E2, but only among postmenopausal women who use ET. 相似文献
54.
Amphiphysin autoimmunity: paraneoplastic accompaniments 总被引:2,自引:0,他引:2
Pittock SJ Lucchinetti CF Parisi JE Benarroch EE Mokri B Stephan CL Kim KK Kilimann MW Lennon VA 《Annals of neurology》2005,58(1):96-107
Amphiphysin-IgG was identified in 71 patients among 120,000 evaluated serologically for paraneoplastic autoantibodies. Clinical information was available for 63 patients. Cancer was detected in 50 (mostly limited), proven histologically in 46, and was imaged intrathoracically in 4 patients (lung, small-cell [27] and non-small cell [1]), breast [16] and melanoma [2]). Neurological accompaniments included (decreasing frequency): neuropathy, encephalopathy, myelopathy, stiff-man phenomena, and cerebellar syndrome. In a case examined neuropathologically, parenchymal T-lymphocyte infiltration (predominantly CD8(+)) was prominent in lower brainstem, spinal cord, and dorsal root ganglion. Coexisting paraneoplastic autoantibodies, identified in 74% of patients, predicted a common neoplasm and indicated other neuronal autoantigen targets that plausibly explained several neurological manifestations; for example, P/Q-type Ca(2+)-channel antibody with Lambert-Eaton syndrome (n = 5), anti-neuronal nuclear antibody type 1 with sensory neuronopathy (n = 7), K(+)-channel antibody with limbic encephalitis (n = 1) or neuromyotonia (n = 1), and collapsin response-mediator protein-5-IgG with optic neuritis (n = 3). Patients with isolated amphiphysin-IgG (n = 19) were more likely to be women (with breast cancer, p < 0.05) and to have myelopathy or stiff-man phenomena (p < 0.01). Overall, a minority of women (39%) and men (12%) had stiff-man phenomena. Only 10% of women (some with lung carcinoma) and 4% of men fulfilled diagnostic criteria for stiff-man syndrome. 相似文献
55.
Ahrens J Haeseler G Leuwer M Mohammadi B Krampfl K Dengler R Bufler J 《Anesthesia and analgesia》2004,99(1):91-96
The anesthetic propofol (2,6 diisopropylphenol) mediates some of its effects by activating inhibitory chloride currents in the lower brainstem and spinal cord. The effects comprise direct activation of gamma-aminobutyric acid-A and glycine receptors in the absence of the natural agonist, as well as potentiation of the effect of submaximal agonist concentrations. Replacement of propofol's isopropyl groups by di-tert-butyl groups yields a compound without in vivo anesthetic effects. We have studied the effects of propofol and 2,6 di-tert-butylphenol on chloride inward currents via rat alpha1beta glycine receptors heterologously expressed in human embryonic kidney cells. Propofol, but not 2,6 di-tert-butylphenol, directly activated glycine receptors; half-maximal current activation was observed with propofol 114 +/- 27 microM. Both compounds potentiated the effect of a submaximal glycine concentration (10 microM) to a maximum value of 136% +/- 71% (propofol) and 279% +/- 109% (2,6 di-tert-butylphenol) of the response to glycine 10 microM. The 50% effective concentration for this effect was 12.5 +/- 6.4 microM and 9.4 +/- 10.2 microM for propofol and 2,6 di-tert-butylphenol, respectively. Propofol and its nonanesthetic structural analog do not differ in their ability to coactivate the glycine receptor but differ in their ability to directly activate the receptor in the absence of the natural agonist. 相似文献
56.
Drancourt M Bodaghi B Lepidi H Le Hoang P Raoult D 《Journal of clinical microbiology》2004,42(4):1822-1825
Bartonella henselae uveitis was diagnosed in a 40-year-old woman with underlying HLA-B27 uveitis on the basis of immunodetection and molecular detection of the organism, a Marseilles genogroup and a CAL-1 genotype strain, in the vitreous fluid. This case illustrates that B. henselae should be included in the differential diagnosis of uveitis and the usefulness of immunodetection for rapid and specific diagnosis. 相似文献
57.
Clinical characteristics of acute HSV-2 retinal necrosis 总被引:2,自引:0,他引:2
Tran TH Stanescu D Caspers-Velu L Rozenberg F Liesnard C Gaudric A Lehoang P Bodaghi B 《American journal of ophthalmology》2004,137(5):872-879
PURPOSE: To report the clinical features and evaluate the visual outcome of eleven cases of herpes simplex virus-2 (HSV-2) related acute retinal necrosis syndrome (ARN). DESIGN: Retrospective interventional case series. METHODS: Twelve eyes of eleven patients from two European centers, diagnosed with HSV-2 related acute retinal necrosis syndrome were retrospectively reviewed. Herpes simplex virus-2 DNA was detected by polymerase chain reaction in intraocular fluids (aqueous and/or vitreous). Findings at initial examination, clinical evolution with antiviral therapy, complications and final visual acuity were evaluated. RESULTS: Herpes simplex virus-2 DNA was detected in all cases. No sample was positive for more than one virus. The mean age of disease in the first eye was 36 years (ranged from 10 to 57 years). Five patients were women and six were men. All patients were immunocompetent. Previous medical history included neonatal herpes (n = 1), previous ARN (n = 3), trauma (n = 1) and systemic corticosteroid administration before occurrence of ARN (n = 3). Preexisting pigmented chorioretinal scars were found in three cases. Patients were treated with high dose intravenous acyclovir or foscarnet +/- intravitreal ganciclovir +/- interferon. The mean follow-up was 14.5 months (from 5 to 22 months). At the end of the follow-up period, five eyes (41.7%) showed improvement of visual acuity of two or more lines. Final visual acuity was 20/60 or better in four eyes (33.3%), 20/400 or better in four eyes (33.3%) and less than 20/400 in four eyes. CONCLUSION: History of neonatal herpes, triggering events such as neurosurgery, periocular trauma, high-dose corticosteroids, and chorioretinal scars suggest that HSV-2 retinitis reflects reactivation of HSV-2 infection. 相似文献
58.
Endobronchial presentation of Hodgkin lymphoma is exceedingly rare and can be confused clinically with pulmonary small cell carcinoma. Because of the dramatic implications in treatment and prognosis, endobronchial Hodgkin lymphoma, despite its uncommon occurrence, should be considered in the differential of small cell carcinoma and necrotizing vasculitides with pulmonary involvement, especially in a relatively young patient with cough, hemoptysis, atelectasis, and hilar or mediastinal lymphadenopathy. The use of photodynamic laser therapy or stent placement for palliative treatment of life-threatening airway obstruction may be required prior to or as an initial adjunct to tumor-specific therapy. 相似文献
59.
60.
DNA adduct formation and oxidative stress in colon and liver of Big Blue rats after dietary exposure to diesel particles 总被引:7,自引:0,他引:7
Dybdahl M Risom L Møller P Autrup H Wallin H Vogel U Bornholdt J Daneshvar B Dragsted LO Weimann A Poulsen HE Loft S 《Carcinogenesis》2003,24(11):1759-1766
Exposure to diesel exhaust particles (DEP) via the gastrointestinal route may impose risk of cancer in the colon and liver. We investigated the effects of DEP given in the diet to Big Blue rats by quantifying a panel of markers of DNA damage and repair, mutation, oxidative damage to proteins and lipids, and antioxidative defence mechanisms in colon mucosa cells, liver tissue and the blood compartment. Seven groups of rats were fed a diet with 0, 0.2, 0.8, 2, 8, 20 or 80 mg DEP/kg feed for 21 days. DEP induced a significant increase in DNA strand breaks in colon and liver. There was no effect on oxidative DNA damage (8-oxodG) in colon or liver DNA or in the urine. However, the mRNA expression of OGG1, encoding an enzyme involved in repair of 8-oxodG, was increased by DEP in both liver and colon. DNA adduct levels measured by 32P-post-labelling were elevated in colon and liver, and the expression of ERCC1 gene was affected in liver, but not in colon. In addition to these effects, DEP exposure induced apoptosis in liver. There was no significant change in mutation frequency in colon or liver. The levels of oxidative protein modifications (oxidized arginine and proline residues) were increased in liver accompanied by enhanced vitamin C levels. In plasma, we found no significant effects on oxidative damage to proteins and lipids, antioxidant enzymes or vitamin C levels. Our data indicate that gastrointestinal exposure to DEP induces DNA adducts and oxidative stress resulting in DNA strand breaks, enhanced repair capacity of oxidative base damage, apoptosis and protein oxidation in colon mucosa cells and liver. 相似文献