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21.
22.
A naive, sexually matureD. melanogaster male tested with a young, sexually immature male will perform vigorous courtship, but the mature male will perform much less courtship if he is subsequently tested with a second young male. This phenomenon is called experience-dependent courtship modification (EDCM). We have shown that exposure to either or both of the two courtship-stimulating pheromones that immature males synthesize is sufficient to induce EDCM. 相似文献
23.
24.
Pulmonary permeability edema in a large animal model of nonpulmonary sepsis. A morphologic study.
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I. Craig D. Judges A. Gnidec M. Lefcoe N. Paterson R. Finley W. Sibbald 《The American journal of pathology》1987,128(2):241-251
Morphologic studies were undertaken in a sheep model of pulmonary permeability edema (PPE) induced by cecal ligation and perforation. Biopsies taken every 24 hours through 96 hours following induction of sepsis showed, at 24 hours, interstitial edema accompanied by widespread aggregation of polymorphonuclear leukocytes. This was confirmed by electron microscopy, which also demonstrated endothelial cell swelling, platelet aggregation, and fibrin deposition. By 48 hours, a "thromboangiitis" had developed that persisted through 96 hours. In vitro pulmonary angiograms done at 60 and 96 hours showed multiple filling defects; it was possible to demonstrate that these defects corresponded to the "thromboangiitis." These thrombotic lesions, which were not the result of embolization from indwelling lines, closely resembled vascular changes described in the adult respiratory distress syndrome. It is believed that this is the first time that such lesions have been described in a model of PPE resulting from nonpulmonary sepsis. 相似文献
25.
Kivihya-Ndugga LE Otieno G Muthami LN Gachihi G Gathua S 《African journal of health sciences》1994,1(3):122-125
Tuberculosis is one of the most frequent opportunistic infections in HIV-infected patients in developing countries. In some instances, manifestations of pulmonary tuberculosis precede all other HIV related signs and symptoms because of the high virulence of M. tuberculosis. In order to characterise the interaction between these two pathogens, clinical and immunological parameters in pulmonary tuberculosis patients with and without HIV infection were compared. Amongst newly diagnosed pulmonary tuberculosis patients the association of some of these changes with the clinical outcome were evaluated. Of these, 44% were co-infected with HIV. Pulmonary tuberculosis patients with HIV-1 presented more frequently with lymphadenopathy and diarrhoea than those without HIV-1. Peripheral blood CD4+ counts were significantly lower in patients with pulmonary tuberculosis with HIV-1 than those with pulmonary tuberculosis alone, P= 0.0292. Low CD4+ lymphocyte counts, lymphadenopathy and BCG scar absence could serve as indicators of HIV-1 infection in pulmonary tuberculosis (PTB) patients. 相似文献
26.
27.
Montalto G Giannitrapani L Soresi M Virruso L Martino DD Gambino R Carroccio A Cervello M 《Inflammation》2001,25(2):101-108
E-selectin, an adhesion molecule of the selectin family, is involved in leukocyte adhesion to the endothelium and in the cellular immunological reactions. Expression of this molecule, in fact, is physiologically absent, but it becomes evident on sinusoidal lining cells during inflammatory liver disease. The aim of this study was to evaluate the behavior of E-selectin in chronic hepatitis C (CH-C) patients with persistently normal transaminase in comparison to patients with CH-C and elevated transaminase, and its changes during alpha-interferon therapy. Immunohistochemical localization of E-selectin was also performed on liver tissue specimens of both groups. Fifty-eight subjects were divided into 3 groups: group A included 18 patients with CH-C and persistently normal transaminase; group B 20 patients with CH-C and persistently elevated transaminase levels and group C included 20 healthy subjects, representing the control group. The first two groups were treated with r-IFN at a dose of 6 MU 3 times a week for 3 months and followed-up with 3 MU 3 times a week for another 3 months. Serum baseline values of E-selectin in groups A and B were significantly higher than those in group C (P < 0.04), but there was no difference between groups A and B. Furthermore, there was a trend toward higher E-selectin values as histological severity increased (r = 0.69; P < 0.0001). Post-treatment E-selectin serum values showed a moderate decrease in both groups, but only among responder patients; while E-selectin levels were unchanged in non responders. Immunohistochemical localization showed no staining for E-selectin in normal liver specimens, while there was a quite similar staining for E-selectin in the two groups of patients. In conclusion, this study shows that serum E-selectin levels in patients with CH-C and persistently normal transaminase are higher than in controls and they are associated with severity of liver disease. Liver of these patients express E-selectin molecules, suggesting an activation of the immune system almost identical to that of patients with CH-C and elevated transaminase. In both groups only responder patients showed a moderate decrease below baseline serum values. 相似文献
28.
Glycoproteins present in human follicular fluid that inhibit the zona- binding capacity of spermatozoa 总被引:1,自引:0,他引:1
Previous studies have suggested that human follicular fluid contains
factors that reduce the zona-binding capacity of spermatozoa. The present
study provides further evidence of the existence of such factors. Using the
hemizona binding assay (HZA), we have shown that the inhibitory effect of
human follicular fluid on the zona-binding capacity of spermatozoa is
concentration-dependent, an inhibitory effect being detected when the
concentration of human follicular fluid was > or = 10%. A 1%
concentration of human follicular fluid did not possess this inhibitory
activity. Heating human follicular fluid at 56 degrees C for 30 min did not
affect its inhibitory properties; treatment with proteinase-K abolished
such inhibition. Human follicular fluid was fractionated sequentially by
concanavalin-A affinity chromatography, Mono Q ion-exchange chromatography
and Superose-12 gel filtration. The zona binding inhibitory activity
resided in the fraction which bound to the lectin and Mono Q column and
contained molecules with native molecular weights of 32 and 192 kDa. Sodium
dodecyl sulphate-polyacrylamide gel electrophoresis analysis suggested that
the 192 kDa glycoprotein was a tetramer, while the 32 kDa glycoprotein
remained as a single molecular species under denaturing conditions. We
conclude that two glycoproteins were responsible for the zona binding
inhibitory activity of human follicular fluid. The physiological role of
these factors remains unclear.
相似文献
29.
Molecular genetic analysis of familial early-onset Alzheimer's disease linked to chromosome 14q24.3 总被引:4,自引:2,他引:4
Cruts Marc; Backhovens Hubert; Wang Sheng-Yue; Van Gassen Geert; Theuns Jessie; De Jonghe Chris; Wehnert Anita; De Voecht Joke; De Winter Goedele; Cras Patrick; Bruyland Marc; Datson Nicole; Weissenbach Jean; Dunnen Johan T.den; Martin Jean-Jaques; Hendriks Lydia; Van Broeckhoven Christine 《Human molecular genetics》1995,4(12):2363-2371
Genetic linkage studies have indicated that chromosome 14q24.3harbours a major locus for early-onset (onset age <65 years)Alzheimer's disease (AD3). Positional cloning efforts have identifieda novel gene S182 or presenilin 1 as the AD3 gene. We have mappedS182 in the AD3 candidate region between D14S277 and D14S284defined by genetic linkage studies in the two chromosome 14linked, early-onset AD families AD/A and AD/B. We have shownthat S182 is expressed in lymphoblasts and have determined thecomplete cDNA in both brain and lymphoblasts by RT-PCR sequencing.S182 is alternatively spliced in both brain and lymphoblastswithin a putative phosphorylation site located 5' in the codingregion. We identified two novel mutations, Ile143Thr and Gly384Alalocated in, respectively, the second transmembrane domain andin the sixth hydrophilic loop of the putative transmembranestructure of S182. As families AD/A and AD/B have a very similarAD phenotype our observation of two mutations in functionallydifferent domains suggest that onset age and severity of ADmay not be very helpful predictors of the location of putativeS182 mutations. 相似文献
30.
Two unusual benign lesions of the neck masquerading as malignancy on fine-needle aspiration cytology
Kristy E. Dundas Maria P. Wong Kenneth C. Suen James L. Finley 《Diagnostic cytopathology》1995,12(3):272-278
Two cases of unusual benign tumors of the neck are described, both of which were initially misdiagnosed on cytology as carcinomas. Fine-needle aspiration findings in each case demonstrated a pleomorphic population of cells including bizarre multi-nucleated giant cells, the latter raising the false impression of malignancy. However, on review the cytological appearances of the tumors, a pleomorphic lipoma and a carotid body tumor, were characteristic. the correct diagnosis in each case would have been made or suggested if the pathologist had been familiar with the cytologic features characteristic of the lesion and the differential diagnosis of the head and neck tumors. in addition, the point is made that adequate clinical information is essential for the pathologist if all relevant conditions are not to be missed in the differential diagnosis. 相似文献