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P. Kalina K. E. Drehobl K. Black R. Woldenberg M. Sapan 《Postgraduate medical journal》1995,71(836):378-379
A woman with an eight-year history of polycythemia vera presented with numbness and weakness of both legs. A large spinal haematoma was revealed on magnetic resonance imaging which was treated clinically and which subsequently resolved. 相似文献
4.
A suspected diagnosis of retinoblastoma can almost always be supported by intraocular calcification detected by computerized tomography. We report two patients with diffuse unilateral opacification of the ocular media who failed to demonstrate calcification on a CT scan. 相似文献
5.
Surfactant protein D enhances phagocytosis and killing of unencapsulated phase variants of Klebsiella pneumoniae 总被引:4,自引:0,他引:4 下载免费PDF全文
Ofek I Mesika A Kalina M Keisari Y Podschun R Sahly H Chang D McGregor D Crouch E 《Infection and immunity》2001,69(1):24-33
Pulmonary surfactant protein D (SP-D) is a collagenous C-type lectin (collectin) that is secreted into the alveoli and distal airways of the lung. We have studied the interactions of SP-D and alveolar macrophages with Klebsiella pneumoniae, a common cause of nosocomial pneumonia. SP-D does not agglutinate encapsulated K. pneumoniae but selectively agglutinates spontaneous, unencapsulated phase variants, such as Klebsiella strain K50-3OF, through interactions with their lipopolysaccharides (LPS). These effects are calcium dependent and inhibited with maltose but not lactose, consistent with involvement of the SP-D carbohydrate recognition domain. Precoating of K50-3OF with SP-D enhances the phagocytosis and killing of these organisms by rat alveolar macrophages in cell culture and stimulates the production of nitric oxide by the NR-8383 rat alveolar macrophage cell line. SP-D similarly enhances the NO response to K50-3OF LPS adsorbed to Latex beads under conditions where soluble LPS or SP-D, or soluble complexes of SP-D and LPS, do not stimulate NO production. Our studies demonstrate that interactions of SP-D with exposed arrays of Klebsiella LPS on a particulate surface can enhance the host defense activities of alveolar macrophages and suggest that activation of macrophages by SP-D requires binding to microorganisms or other particulate ligands. Because unencapsulated phase variants are likely to be responsible for the initial stages of tissue invasion and infection, we speculate that SP-D-mediated agglutination and/or opsonization of K. pneumoniae is an important defense mechanism for this respiratory pathogen in otherwise healthy individuals. 相似文献
6.
Garaczi E Széll M Jánossy T Koreck A Pivarcsi A Buzás E Pos Z Falus A Dobozy A Kemény L 《International immunology》2004,16(12):1781-1788
Histamine plays an important role in the regulation of various immunological functions. To evaluate the role of histamine in contact hypersensitivity, contact dermatitis was induced with dinitrofluorobenzene (DNFB) in histidine decarboxylase knockout (HDC-/-) histamine-deficient and wild-type mice. The DNFB-induced increase of the ear thickness was significantly higher in HDC-/- mice than in wild-type mice. Using flow cytometry, significantly lower percentages of CD4+ Th and CD8+ Tc cells, and significantly higher percentages of CD45R+ B cells were observed in the regional lymph nodes in HDC-/- mice than in wild-type mice. In the ear specimens of both groups, the majority of the infiltrating cells were neutrophils and macrophages at 24 and 48 h after challenge. Using immunohistochemistry, we observed significantly more CD45+ leukocytes in HDC-/- mice than in wild-type mice. The expression of Th1 (IL-2, IFN-gamma, TNF-alpha) and Th2 (IL-4) mRNAs was examined by quantitative real time RT-PCR in the ear samples. The levels of Th1 cytokine mRNAs both at 24 and 48 h after challenge and IL-4 mRNA at 48 h showed a significantly higher increase in HDC-/- mice than in wild-type mice. These results suggest that histamine plays a negative immunoregulatory role in DNFB-induced contact hypersensitivity. 相似文献
7.
Eldar-Geva T Margalioth EJ Gal M Ben-Chetrit A Algur N Zylber-Haran E Brooks B Huerta M Spitz IM 《Human reproduction (Oxford, England)》2005,20(7):1814-1819
BACKGROUND: Anti-Mullerian hormone (AMH) is expressed in pre- and small-antral follicles. High serum levels are found in women with polycystic ovaries (PCO), accordant with their increased content of small follicles. To evaluate the relationship between AMH, folliculogenesis and hyperandrogenism, we compared serum AMH levels between women with PCO with and without hyperandrogenism and normal controls during controlled ovarian hyperstimulation (COH). METHODS: Nineteen women with PCO and hyperandrogenism (group A), 10 women with PCO but no hyperandrogenism (group B) and 23 ovulatory women with normal ovarian morphology (group C, controls) underwent COH with the long protocol. Serum levels of AMH, estradiol, androstenedione and follicular tracking were determined before gonadotropins treatment (day 0) and every 2-4 days up to the day of HCG administration. RESULTS: AMH levels declined gradually throughout COH in the three groups, but remained higher in groups A and B compared with the controls. Significantly higher levels were found in group A compared with group B, despite comparable numbers of small follicles. Multiple regression analysis revealed that both the number of small follicles and serum androgens were correlated to AMH. CONCLUSIONS: Women with PCO have higher serum AMH levels during COH than controls. Hyperandrogenism is associated with an additional increase in AMH. It is conceivable that hyperandrogenism may reflect more severe disruption of folliculogenesis in women with PCO or may affect AMH secretion. 相似文献
8.
The anterior or rostrolateral prefrontal cortex (RLPFC) is frequently recruited during complex cognitive tasks across a wide range of domains, including reasoning, long-term memory retrieval, and working memory. The authors report an event-related functional MRI study, indicating that the RLPFC is specifically involved in the evaluation of internally generated information--or information that cannot be readily perceived from the external environment but has to be inferred or self-generated. The findings are consistent with a hierarchical model of lateral prefrontal organization, with RLPFC contributing only at the highest orders of cognitive transformations. This characterization of RLPFC function may help explain seemingly disparate findings across multiple cognitive domains and could provide a unified account of this region's contribution to human cognition. 相似文献
9.
Archives of Sexual Behavior - Adolescence is a critical time in the U.S. for religious development in that many young people eschew their religious identity as they enter adulthood. In general,... 相似文献
10.
P53 overexpression as an indicator of overall survival and response to treatment in osteosarcomas 总被引:5,自引:0,他引:5
Pápai Z Féja CN Hanna EN Sztán M Oláh E Szendrôi M 《Pathology oncology research : POR》1997,3(1):15-19
The p53 gene located at chromosome 17pl3 is found to be altered (allelic loss or other mutation) in multiple human cancers,
including osteosarcomas. The mutated gene produces a protein with a prolonged half-life thus rendering it detectable by conventional
immunohistochemistry. We examined the correlation between p53 expression and clinical prognosis as well as response to therapy.
Twentyone patients with previously untreated and histologically verified highly malignant osteosarcoma were used for this
study. Biopsy material taken both prior to the start of COSS 91 protocol and at the time of surgery (ten weeks later) was
examined for alterations in p53 protein expression and drug resistance. Two patients who had strong (+++) p53 protein expression
and three others who became positive during the chemotherapy had significantly worse prognosis (all of them died within one
year) than those who showed no p53 expression both at biopsy and after chemotherapy (all 11 patients are alive, average follow-up
time: 3.5 years). All patients who showed any kind of positive p53 protein expression on initial biopsy were non-respon-ders
to chemotherapy. In contrast, 69% (9 out of 13) of those who exhibited no p53 expression on initial biopsy were responders
or intermediate responders to chemotherapy. We concluded that p53 expression may be a useful prognostic factor in osteosarcomas.
The direct correlation between p53 positive expression and resistance to therapy can help in identifying patients who are
in need of a more vigorous or different chemotherapeutical protocol. 相似文献