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11.
The clinical history and histological features of seven cases of granulomatous mastitis are presented. The lesion occurs in young parous women as a tender extra-areolar breast lump. Histologically, non-caseating discrete granulomas are present, confined to breast lobules with, in three cases, coalescence of the granulomas and microabscess formation. Pathogenesis of the changes is discussed. It is thought that granulomatous mastitis is an entity morphologically distinct from duct ectasia/plasma cell mastitis and the commoner forms of granulomatous breast diseases. 相似文献
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In vitro activation of natural killer-like cytotoxicity by specifically in vivo primed T-helper lymphocytes in the rat. 总被引:1,自引:0,他引:1 下载免费PDF全文
The interaction between the rat non-cytotoxic T lymphocyte subset, which is marked by the W3/25 monoclonal antibody, and natural killer cells was investigated. Specifically in vivo primed lymph node cells were restimulated in vitro with the priming antigen and co-cultured with a source of natural killer cells and their precursors. Cytotoxic activity, generated during a 4 day incubation period, was assessed by lysis of a rat natural killer cell-sensitive tumour target cell line, y3Ag123. This cytotoxic activity was more fully described as natural killer cell cytotoxicity on the basis of target cell specificity, using a range of natural killer cell-susceptible and -resistant targets. The W3/25-positive T cell, separated from the in vivo primed lymph node cells by nylon wool column elution, antibody labelling and sorting on the fluorescence-activated cell sorter, was shown to be necessary to stimulate the generation of this activity. W3/25-negative cells were not active in this respect. The activation was shown to be mediated via lymphokine(s), probably interleukin-2, present in concanavalin A-induced lymphocyte culture supernatants. These supernatants could be used to substitute for in vivo primed, restimulated W3/25-positive lymph node cells in activating natural killer cell cytotoxicity from normal spleen cells. Nylon wool column-eluted spleen cells, activated in vitro with conditioned medium were separated into OX8-positive and OX8-negative subsets using the fluorescence-activated cell sorter. The distribution of cytotoxic activity related to that of freshly derived rat natural killer cells. 相似文献
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BACKGROUND. Research suggests that patients are more satisfied with patient-centred consultations than with doctor-centred consultations and that some health measures are positively influenced by this type of consultation. Research on the factors that influence the patient centredness of the consultation is sparse but suggests that women doctors are more patient centred than men doctors. AIM. A study was designed, first, to confirm or reject the suggestion that women general practitioners are more patient centred than men general practitioners and, secondly, to determine some of the factors that might influence the patient centredness of a general practitioner. METHOD. The audiotaped consultations of 41 general practitioners were analysed using an instrument designed to measure patient centredness. The general practitioners were selected from a group of volunteers to represent both sexes as well as a wide range of age and experience. RESULTS. The results of the analysis showed that women general practitioners, particularly trainers, had higher patient-centredness scores than men general practitioners. This behaviour is characterized by an increased frequency of open questions and greater attention to patient offers (anything of potential significance that a patient brings to the general practitioner consultation). Additionally, the combination of sexes in a consultation seemed to have an effect on the interaction, with woman general practitioner/female patient dyads (pairings) having the highest median patient-centredness score, woman general practitioner/male patient and man general practitioner/male patient dyads scoring the same as each other and man general practitioner/female patient dyads having the lowest median scores. CONCLUSION. The results suggest that women general practitioners, in this sample, were more patient centred than men general practitioners. The results also suggest that inherent inequalities exist, with female patients receiving a more patient-centred service from general practitioners of their own sex than from general practitioners of the opposite sex. Male patients, on the other hand, seemed to fare equally well, irrespective of the sex of their general practitioner. Training is required to address these inequalities and to improve the level of patient centredness in the consultation. 相似文献
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Billette J; Janse MJ; van Capelle FJ; Anderson RH; Touboul P; Durrer D 《The American journal of physiology》1976,231(4):1129-1139
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The medial superior temporal area of extrastriate cortex (MST) contains signals selective for nonuniform patterns of motion often termed "optic flow." The presence of such tuning, however, does not necessarily imply involvement in perception. To quantify the relationship between these selective neuronal signals and the perception of optic flow, we designed a discrimination task that allowed us to simultaneously record neuronal and behavioral sensitivities to near-threshold optic flow stimuli tailored to MST cells' preferences. In this two-alternative forced-choice task, we controlled the salience of globally opposite patterns (e.g., expansion and contraction) by varying the coherence of the motion. Using these stimuli, we could both relate the sensitivity of neuronal signals in MST to the animal's behavioral sensitivity and also measure trial-by-trial correlation between neuronal signals and behavioral choices. Neurons in MST showed a wide range of sensitivities to these complex motion stimuli. Many neurons had sensitivities equal or superior to the monkey's threshold. On the other hand, trial-by-trial correlation between neuronal discharge and choice ("choice probability") was weak or nonexistent in our data. Together, these results lead us to conclude that MST contains sufficient information for threshold judgments of optic flow; however, the role of MST activity in optic flow discriminations may be less direct than in other visual motion tasks previously described by other laboratories. 相似文献
19.
An improved colorimetric PCR-based method for detection and differentiation of Entamoeba histolytica and Entamoeba dispar in feces. 下载免费PDF全文
D Britten S M Wilson R McNerney A H Moody P L Chiodini J P Ackers 《Journal of clinical microbiology》1997,35(5):1108-1111
The epidemiological implications of the recent separation of "Entamoeba histolytica" into two separate species, pathogenic E. histolytica sensu stricto and commensal E. dispar, will not become apparent without methods of distinguishing between them which are applicable to large numbers of specimens. We have modified a PCR-based method to produce such a technique which may be completed in 1 day while still identifying 10(-1) E. histolytica and 1 to 10 E. dispar trophozoites per g of feces when present separately and 10 E. histolytica and 100 E. dispar trophozoites per g in the presence of 10(6) trophozoites per g of the other species. Applied to fecal specimens from 18 patients from which E. histolytica or E. dispar had been grown and identified to the species level by hexokinase isoenzyme analysis, the method in every case yielded the correct result. Positive and negative results are easily distinguished by eye, and we are now applying this technique to a large-scale epidemiological study of amebiasis in the eastern Mediterranean region. 相似文献
20.
Breast cancer detection: one versus two views 总被引:2,自引:0,他引:2
Mammographic examinations of 169 patients with 172 biopsy-proved carcinomas, and of 194 healthy subjects, were interpreted independently and retrospectively by three experienced mammographers, initially as single-view oblique examinations and 6 months later as two-view oblique-cephalocaudal examinations. For the single-view examinations of the cancer patients, 67% of the cancers were correctly recommended for biopsy, additional views were requested for 23%, and a "negative" interpretation was made for 10%. For the single-view examinations of healthy subjects, biopsy was recommended for 7% and additional views were recommended for 32%. For the two-view examinations of women with cancer, 80% of the cancers were correctly recommended for biopsy, additional views were requested for 4%, and a "negative" interpretation was made for 16%. For two-view examinations of healthy subjects, biopsy was recommended for 7% and additional views were requested for only 5%. The authors conclude that single-view screening should not be performed, because it would lead to an excessive number of "call-back" examinations of healthy patients, producing additional cost and anxiety that would outweigh any theoretical benefit. 相似文献