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61.
Paul  CC; Baumann  MA 《Blood》1990,75(1):54-58
Spontaneous outgrowth of immortalized Epstein-Barr virus (EBV) infected B-cell clones will occur from cultures of peripheral blood mononuclear cells (PBMNCs) of some persons with a history of EBV infection. We determined that outgrowth of such clones may be reproducibly modulated by supplementation of cultures with the hematopoietic growth factors GM- CSF and interleukin-3 (IL-3). Continuous supplementation of cultures with GM-CSF facilitates emergence of immortalized B-cell clones, whereas supplementation with IL-3 completely prevents their emergence. The effect of GM-CSF may be direct, at least in part, as the proliferation of pure clones of EBV-transformed B lymphocytes was augmented in response to GM-CSF. An indirect mechanism appears to be responsible for the inhibition of transformed B-cell outgrowth in response to IL-3, as IL-3 had no inhibitory effect on proliferation of pure transformed B-cell clones and IL-3-mediated inhibition could be eliminated by antibody neutralization of gamma-interferon (gamma-IFN) or tumor necrosis factor-alpha (TNF-alpha) early in culture. The mechanisms of these effects deserve further study and may have clinical relevance to use of hematopoietic growth factors for support of bone marrow (BM) function in immunocompromised patients.  相似文献   
62.
Chronic neutrophilic airway inflammation is an important feature of cystic fibrosis (CF). Noninvasive inflammatory markers may be useful in monitoring CF. Leukotriene B4 (LTB4) and interleukin (IL)-6 are inflammatory mediators that are increased in chronic neutrophilic inflammation. The aim of this study was to assess whether LTB4 and IL-6 were increased in exhaled breath condensate of CF patients and whether they could be used to monitor inflammation. Twenty patients with CF (13 males, age of 28 +/- 9 years) were recruited together with 15 age-matched healthy subjects (8 males, age 35 +/- 7 years). LTB4 and IL-6 levels were markedly elevated in patients with acute exacerbations (28.8 +/- 4.3 and 8.7 +/- 0.4 pg/ml) compared with control subjects (6.8 +/- 0.7 and 2.6 +/- 0.1 pg/ml, p < 0.0001). We also observed a decrease of exhaled LTB4 and IL-6 concentrations after antibiotic treatment in six patients who were followed until clinically stable (31.1 +/- 4.4 and 9.5 +/- 0.4 pg/ml vs. 18.8 +/- 0.8 and 6.4 +/- 0.2 pg/ml, respectively) and an increase in 15 CF patients infected with Pseudomonas aeruginosa (34.3 +/- 5.0 and 9.3 +/- 0.3 pg/m) compared with those infected with other bacteria (18.3 +/- 0.7 and 6.9 +/- 0.5 pg/ml). These findings suggest that LTB4 and IL-6 levels are increased in exhaled breath condensate of patients with CF during exacerbation and could be used to monitor airway inflammation in these patients.  相似文献   
63.
(1) Background: Breastfeeding duration may be reduced in women with type 2 diabetes. Delayed secretory activation (SA) is associated with poorer breastfeeding outcomes; however, no prior studies have examined SA in women with type 2 diabetes. This pilot study aimed to assess SA in women with type 2 diabetes by assessing breastmilk constituents. Secondary aims were to assess breastfeeding rates postpartum, and contributory factors. (2) Methods: A prospective cohort of pregnant women with type 2 diabetes (n = 18) and two control groups with age- and parity-matched nondiabetic pregnant women (body mass index (BMI)) matched (n = 18) or normal-range BMI (n = 18)) were recruited. Breastmilk constituents (citrate, lactose, protein, and fat) were measured twice daily for 5 days postpartum and compared between groups. Associations between peripartum variables, breastmilk constituents, and breastfeeding at 4 months postpartum were explored. (3) Results: Women with type 2 diabetes had a slower increase in breastmilk citrate concentration postpartum, indicative of delayed SA, compared to both control groups. Higher predelivery insulin doses in women with type 2 diabetes were associated with increasing time to SA. Both women with type 2 diabetes and BMI-matched controls were less likely to fully breastfeed at 4 months, compared with normal-BMI controls. (4) Conclusion: SA is delayed in women with type 2 diabetes when compared to BMI-matched and normal-BMI women. Women with type 2 diabetes are less likely to fully breastfeed, at hospital discharge and by 4 months postpartum, compared to women with normal-BMI.  相似文献   
64.
Immature avulsed teeth are not usually treated with pulp revascularization because of the possibility of complications. However, this therapy has shown success in the treatment of immature teeth with periapical lesions. This report describes the case of an immature replanted tooth that was successfully treated by pulp revascularization. An 8‐year‐old boy suffered avulsion on his maxillary left lateral incisor. The tooth showed incomplete root development and was replanted after 30 minutes. After diagnosis, revascularization therapy was performed by irrigating the root canal and applying a calcium hydroxide paste and 2% chlorhexidine gel for 21 days. In the second session, the intracanal dressing was removed and a blood clot was stimulated up to the cervical third of the root canal. Mineral trioxide aggregate was placed as a cervical barrier at the entrance of the root canal and the crown was restored. During the follow‐up period, periapical repair, apical closure and calcification in the apical 4 mm of the root canal was observed. An avulsed immature tooth replanted after a brief extra‐alveolar period and maintained in a viable storage medium may be treated with revascularization.  相似文献   
65.
Inside the lactating breast: the latest anatomy research   总被引:1,自引:0,他引:1  
Although it is well recognized that a thorough understanding of the anatomy of an organ is essential to enable assessment of any abnormalities in that organ, there has been little investigation of the anatomy of the normal lactating breast since Sir Astley Cooper performed detailed dissections of the anatomy of the breast more than 160 years ago. Many mothers recognize that breast milk provides the ultimate nutrition and protection for the infant; however, a significant proportion of women experience difficulties breastfeeding, some of which lead to weaning the infant. Recently, a small number of studies have focused on the gross anatomy of the breast, and have found that the ductal system is comprised of fewer numbers of main ducts than previously thought. In addition, the ducts are compressible and do not contain large amounts of milk, the amount of fatty tissue in the breast is variable, and a proportion is situated within the glandular tissue. These findings add to our understanding of both the physiology and pathology of the lactating breast.  相似文献   
66.
目的探讨腹腔镜外科技术在胃肠道肿瘤手术中的应用。方法经电视腹腔镜行胃肠道肿瘤手术18例,其中右半结肠切除术4例,横结肠癌根治术3例,乙状结肠癌根治术5例,乙状结肠癌姑息切除术并肝转移癌电凝固化1例,胃癌术后复发转移行探查活检1例,胃巨大恶性淋巴瘤行探查活检1例,晚期回肠癌行小肠侧侧吻合术1例,乙状结肠腺瘤切除术2例。结果均获成功,无中转开腹,手术时间平均165.0分钟。术后平均31.2小时胃肠功能恢复,无并发症发生,术后平均住院8.2天。13例切除肿瘤的结肠癌术后随访2月~30月,仅1例横结肠癌术后23月出现肺转移。结论腹腔镜胃肠肿瘤手术损伤小、恢复快、胃肠干扰小、术后疼痛轻,值得进一步探索开展。  相似文献   
67.
Renal vein thrombosis can occur as a complication of nephrotic syndrome. We present the case of a young man with nephrotic syndrome caused by minimal change disease who developed acute inferior vena cava and left renal vein thrombosis. He was treated initially with intravenous heparin. Because of the persistence of severe left flank pain and gross hematuria, local infusion of recombinant tissue plasminogen activator was tried, with resolution of thrombi and subsidence of symptoms. Functional preservation of the involved kidney is good, as indicated by Tc-99m DMSA scan (involved kidney, 47.4%; uninvolved kidney, 52.6%). Anticoagulation is usually recommended as the treatment of choice in renal vein thrombosis. We believe that in cases with critical presentations, such as bilateral involvement, extension into inferior vena cava, acute renal failure, pulmonary embolism or severe flank pain, thrombolytic therapy should be considered as a second-line treatment if good response is not obtained with heparin.  相似文献   
68.
69.
The late Paul Garrod, in whose honour this lecture is named, was 'the right man at the right time'. He seized the opportunities offered by the dawning of the chemotherapeutic era with vigour and enthusiasm and was a formidable link between the traditional laboratory-based bacteriologist and the more clinically orientated 'modern' medical microbiologist. Professor Garrod was a founder member of the British Society for Antimicrobial Chemotherapy and I had the privilege of meeting him on many occasions. He would have relished the many challenges facing today's microbiologists, infectious disease physicians and public health experts. These will have major implications for antimicrobial chemotherapy in the twenty-first century. The emergence and prevalence of infectious diseases, and the necessity for discovering therapies to treat them, are influenced by many factors. In this lecture I will discuss four which could have a major influence on infectious diseases in the twenty-first century-global warming, biological warfare/terrorism, the dissemination of infections, including those caused by resistant pathogens, by travellers and certain untreatable zoonotic diseases.  相似文献   
70.
Effect of lung-volume-reduction surgery in patients with severe emphysema   总被引:17,自引:0,他引:17  
BACKGROUND: Although many patients with severe emphysema have undergone lung-volume-reduction surgery, the benefits are uncertain. We conducted a randomized, controlled trial of the surgery in patients with emphysema. Patients with isolated bullae were excluded because such patients are known to improve after bullectomy. METHODS: Potentially eligible patients were given intensive medical treatment and completed a smoking-cessation program and a six-week outpatient rehabilitation program before random assignment to surgery or continued medical treatment. After 15 patients had been randomized, the entry criteria were modified to exclude patients with a carbon monoxide gas-transfer value less than 30 percent of the predicted value or a shuttle-walking distance of less than 150 m, because of the deaths of 5 such patients (3 treated surgically and 2 treated medically). RESULTS: Of the 174 subjects who were initially assessed, 24 were randomly assigned to continued medical treatment and 24 to surgery. At base line in both groups, the median forced expiratory volume in one second (FEV1) was 0.75 liter, and the median shuttle-walking distance was 215 m. Five patients in the surgical group (21 percent) and three patients in the medical group (12 percent) died (P=0.43). After six months, the median FEV1 had increased by 70 ml in the surgical group and decreased by 80 ml in the medical group (P=0.02). The median shuttle-walking distance increased by 50 m in the surgical group and decreased by 20 m in the medical group (P=0.02). There were similar changes on a quality-of-life scale and similar changes at 12 months of follow-up. Five of the 19 surviving patients in the surgical group had no benefit from the treatment. CONCLUSIONS: In selected patients with severe emphysema, lung-volume-reduction surgery can improve FEV1, walking distance, and quality of life. Whether it reduces mortality is uncertain.  相似文献   
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