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81.
We describe three patients who had typical features of hairy cell leukemia (HCL) and multiple myeloma (MM) at the same time. In two, both diagnoses were made within a short period of time, and in the third, HCL had been present for 2 yr before the appearance of a paraprotein, bone lesions, and plasma-cell infiltrates established the diagnosis of MM. Although this association has not been previously reported, cases of HCL with osteolytic lesions or a paraprotein band have been described. The cases described may represent clinical manifestations of closely related disorders arising from divergent differentiation from a common B-cell precursor rather than a chance association.  相似文献   
82.
Freeman  SD; Kelm  S; Barber  EK; Crocker  PR 《Blood》1995,85(8):2005-2012
CD33 is a member of the Ig superfamily that is restricted to cells of the myelomonocytic lineage but whose functions and binding properties are unknown. It shares sequence similarity with sialoadhesin, CD22, and the myelin-associated glycoprotein, which constitute the Sialoadhesin family of sialic acid-dependent cell adhesion molecules. In the present study, we show that CD33 is a fourth member of this family. As a model for sialic acid-dependent binding, human erythrocytes were derivatized with N-acetylneuraminic acid (NeuAc) in different linkages. A recombinant soluble form of CD33, Fc-CD33, bound red blood cells with a specificity similar to that of sialoadhesin, preferring NeuAc alpha 2,3Gal in N- and O-glycans over NeuAc alpha 2,6Gal in N-glycans. Fc- CD33 also bound selectively to the myeloid cell lines HL-60 and U937. However, CD33 was unable to mediate cell binding after transient expression in COS cells, despite high levels of surface expression. Pretreatment of the CD33-transfected cells with sialidase rendered them capable of mediating sialic acid-dependent binding. These results show that CD33 can function as a sialic acid-dependent cell adhesion molecule and that binding can be modulated by endogenous sialoglycoconjugates when CD33 is expressed in a plasma membrane.  相似文献   
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Eighty-nine biliary strictures in 73 patients who had undergone percutaneous balloon dilatation were reviewed to determine long-term patency rates and clinical management problems. The majority of dilatations were performed in patients with anastomotic strictures (n = 44), iatrogenic strictures (n = 28), and strictures associated with sclerosing cholangitis (n = 17). Patency rates after 36 months or more were 67%, 76%, and 42%, respectively. Complications, mostly minor, occurred in less than 7% of patients. Of patients with significant biliary obstruction, 15% had little or no intrahepatic biliary duct dilatation demonstrated by cross-sectional imaging and/or direct cholangiography. No definite conclusions could be drawn about the utility of long-term internal/external stenting.  相似文献   
88.
Aim: To investigate mothers’ perceptions of breastfeeding and influences from their social network. Methods: A cross‐sectional survey was carried out in Mangochi district, Malawi where questionnaire data from 157 rural and 192 semi‐urban mother–infant pairs were obtained. Results: The proportion of mothers who thought that exclusive breastfeeding should last for 6 months and those who reported to have actually exclusively breastfed were 40.1% and 7.5% respectively. Of those who reported practising exclusive breastfeeding for 6 months, 77.5% stated that exclusive breastfeeding should last for 6 months. This opinion was independently associated with giving birth in a Baby‐Friendly facility, OR = 5.22; 95% CI (1.92–14.16). Among the mothers who thought that exclusive breastfeeding should last for less than 6 months, 43.9% reported having been influenced in their opinion by health workers. Infant crying was the most common (62.4%) reason for stopping exclusive breastfeeding. Conclusion: The findings illustrate the positive impact health workers can have, as well as the need to raise awareness of the benefits of exclusive breastfeeding among both health workers and mothers. Furthermore, continued counselling of mothers on how to deal with stressful infant behaviour such as crying may assist to prolong exclusive breastfeeding.  相似文献   
89.
In a prospective survey of infants born in a single maternity unit, asymptomatic faecal colonisation by Clostridium difficile occurred in 31 (47%) of 66 babies who provided a faecal sample during week one of life and at age 14 and 28 days, and in 46 (30.7%) of the total of 150 babies for whom at least one faecal sample was obtained during the month of study. There was no evidence for acquisition of the organism from the mother during delivery and colonisation was unrelated to the means of delivery, infant sex, means of feeding, duration of hospital stay, or antibiotic treatment. New colonisation occurred throughout the month of the study and further evidence for environmental acquisition was obtained by the finding of a similar strain of C difficile in 7 babies from one ward together with positive environmental cultures. Colonisation was frequently transient and occasionally intermittent; most infants kept the same strain during their period of carriage. Twenty two (47.8%) babies colonised by C difficile had low titres of cytopathic faecal toxin but none had symptomatic diarrhoea or features of necrotizing enterocolitis. The in vitro toxigenic potential of 57 toxigenic isolates from 36 babies was low and 12 babies carried non-toxigenic strains. Transient colonisation by C difficile in early life is almost certainly more common than is generally recognized and the neonate provides an important reservoir of potential infection.  相似文献   
90.
Jolles  PR; Shin  MS; Jones  WP 《Radiology》1986,159(3):647-651
A retrospective morphologic study of 80 cases was undertaken to determine factors affecting detectability of computed tomographically (CT) proved aortopulmonary (AP) window lesions on conventional posteroanterior (PA) and lateral chest radiographs. Criteria used for determining abnormality were: solitary lymph node enlargement over 1.5 cm or three or more 1-cm nodes and obvious large masses or vascular anomalies. CT scans and corresponding PA and lateral radiographs were analyzed for lesion detectability, size, and location. In 49% of cases there was no detectable lesion in the AP window on radiographs; a definite AP window lesion was seen in 41%, and 10% were equivocal. Major contributing factors to low detectability of AP window lesions on radiographs include size and, more important, location of the lesion. An additional 45 cases of CT-proved normal AP windows were retrospectively reviewed to determine the false-positive rate of PA and lateral radiographs in detection of AP window lesions: 43 (96%) were classified as negative, the remaining two (4%) as equivocal. Although the AP window is a small space, it is the site of many pathologic conditions; the study results indicate that CT may be an essential procedure for its evaluation.  相似文献   
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