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91.
Hematogones: a multiparameter analysis of bone marrow precursor cells   总被引:1,自引:1,他引:1  
Morphologically distinct lymphoid cells with homogeneous, condensed chromatin and scant cytoplasm can be observed in large numbers in the bone marrow of children with a variety of hematologic and nonhematologic disorders. In some patients, these cells may account for greater than 50% of the bone marrow cells, creating a picture that can be confused with acute lymphoblastic leukemia (ALL) or metastatic tumor. Although originally called hematogones (HGs), a variety of other names have been proposed for these unique cells. The clinical significance of expanded HGs has not been resolved, and the biologic features of these cells are incompletely described. In this study, we correlate the clinical, morphologic, cytochemical, flow cytometric, molecular, and cytogenetic properties of bone marrow samples from 12 children with substantial numbers of HGs (range 8% to 55% of bone marrow cells). Diagnoses in these patients included anemia, four; neutropenia, one; anemia and neutropenia, one; idiopathic thrombocytopenic purpura, two; retinoblastoma, two; Ewing's sarcoma, one; and germ cell tumor, one. Flow cytometric analyses of bone marrow cells demonstrated a spectrum extending from early B-cell precursors (CD10+, CD19+, TdT+, HLA-Dr+) to mature surface immunoglobulin-bearing B cells in these patients, corroborating our morphologic impression of HGs, intermediate forms, and mature lymphocytes. DNA content was normal, and no clonal abnormality was identified by either cytogenetic or immunoglobulin and T-cell receptor (TCR) gene rearrangement studies. Follow-up ranged from 3 months to 3 years. None of the patients has developed acute leukemia or bone marrow involvement by solid tumor. The possible role of HGs in immune recovery and hematopoiesis is presented.  相似文献   
92.
We have investigated the effect of type beta transforming growth factor (TGF-beta) on the differentiation of skeletal muscle myoblasts. TGF-beta potently (ID50 approximately 10 pM) prevents established cell lines and primary cultures of rat and chicken embryo myoblasts from fusing into multinucleated myotubes. Inhibition of morphological differentiation by TGF-beta correlates with inhibition of the expression of muscle-specific mRNAs and proteins, strong induction of extracellular matrix type I collagen and fibronectin, and a marked tendency of the treated myoblasts to aggregate into densely multilayered arrays or clusters. Myogenic differentiation can resume after removal of TGF-beta from the medium. Examination of the time of action of TGF-beta shows that myoblasts stochastically reach a point beyond which they become insensitive to the inhibitory action of TGF-beta. This resistance of committed myoblasts to the inhibitory action of TGF-beta is not associated with any measurable change in the number or affinity of TGF-beta receptors in those cells. The results indicate that TGF-beta is a potent inhibitor of myogenesis and may regulate muscle development in vivo.  相似文献   
93.

OBJECTIVE:

To describe services received by preschool children diagnosed with autism spectrum disorder (ASD) during the five-year period following their diagnosis.

METHOD:

An inception cohort of preschoolers diagnosed with ASD from Halifax (Nova Scotia), Montreal (Quebec), Hamilton (Ontario), Edmonton (Alberta) and Vancouver (British Columbia) were invited to participate. Parents/caregivers (n=414) described the services provided to their children at four time points: baseline (T1; within four months of diagnosis; mean age three years); six months later (T2); 12 months later (T3); and at school entry (T4). Data were first coded into 11 service types and subsequently combined into four broader categories (no services, behavioural, developmental and general) for analysis.

RESULTS:

More than 80% of children at T1, and almost 95% at T4 received some type of service, with a significant number receiving >1 type of service at each assessment point. At T1, the most common service was developmental (eg, speech-language therapy). Subsequently, the most common services were a combination of behavioural and developmental (eg, intensive therapy based on applied behaviour analysis and speech-language therapy). Service provision varied across provinces and over time.

DISCUSSION:

Although most preschool children with ASD residing in urban centres were able to access specialized services shortly after diagnosis, marked variation in services across provinces remains a concern.  相似文献   
94.
Theodorsson  B; Hedner  U; Nilsson  IM; Kisiel  W 《Blood》1983,61(5):973-981
A method for specific removal of large amounts of factor IX:C alloantibodies by a resin to which highly purified factor IX was linked (factor IX CH-Sepharose) is described. Factor IX was isolated from human plasma by a three-step procedure, including barium citrate adsorption and elution, DEAE-Sepharose CL-6B chromatography, and dextran sulfate agarose chromatography. Approximately 100 mg factor IX was obtained from 60 liters of plasma. The preparation was about 95% pure as judged by SDS-PAA gel electrophoresis. Its specific coagulant activity was 160 U/mg (IX) and its factor IX clotting antigen (IX:Ag) 500-600 U/mg. Essentially quantitative coupling of the factor IX preparation to activated CH-Sepharose 4B was obtained (4 mg factor IX/ml gel; 2300-3000 U/IX:Ag/ml). This resin bound 1500-2000 U factor IX inhibitor/ml gel and could be re-used at least 5 times without any loss in binding capacity. The binding capacity was dependent on the flow rate. No signs of activation of the coagulation, fibrinolytic, or complement system were observed in vitro. Using this factor IX resin, factor IX alloantibodies were isolated and found to consist of two portions, one minor bound to the resin only in the presence of Ca2+ and another major portion Ca2+ independent. The specific inhibitory activity/milligram IgG of the Ca2+-dependent alloantibodies was about 5 times higher in the presence of Ca2+. It is concluded that 25 ml of the factor IX resin described can remove about 40,000 factor IX inhibitor units (comparable to 120,000 Bethesda U) in one run, provided the flow rate does not exceed 20 ml/hr. By using such a technique for removal of antibodies it seems feasible to convert hemophilia-B patients complicated with inhibitors against factor IX into ordinary hemophilia- B patients for treatment at an emergency or in association with major surgery.  相似文献   
95.
Summary. Patients with moderate and severe haemophilia are evaluated on a regular basis at their haemophilia centres but patients with mild haemophilia are seen less often because of fewer problems related to their disease. The needs of patients with milder forms of haemophilia, however, are often underestimated, both by the patient and staff at healthcare facilities. This study evaluated the knowledge of disease and adherence to treatment among patients with severe, moderate and mild haemophilia. This was a prospective multicentre study performed in Haemophilia Centres in Scandinavia. A total of 413 (67%) of 612 patients aged >25 years with mild, moderate and severe haemophilia completed a self‐administered questionnaire. The mean age of the respondents was 49.7 years (range 25–87 years). Of the 413 respondents, 150 had a mild, 86 had a moderate and 177 had a severe form of haemophilia. A total of 22 (5%) patients did not know the severity of their disease, and 230 (56%) patients knew the effect of factor concentrate in the blood. Of the 413 respondents, 53 (13%) of the cohort never treated a haemorrhage. Patients with mild haemophilia, P ≤ 0.001, were the least likely to treat a haemorrhage. The relative number of patients who were afraid of virus transmission by factor concentrate was about similar in the three groups, 27% of those with severe haemophilia, 26% with moderate and 24% with mild haemophilia. This study shows that the amount of knowledge among haemophilia patients about their disease and treatment is somewhat limited, and demonstrates the importance of continually providing information about haemophilia and treatment, especially to patients with a mild form of the disease.  相似文献   
96.
97.
Objectives The aim of this study was to test the efficacy of latanoprost in eyelash alopecia areata (AA). Design This study is a 2‐year prospective, non‐blinded, non‐randomized, bilateral eyelash alopecia controlled study. Setting The setting of this study was Trichology Unit, Virgen Macarena University Hospital, Seville, Spain. Patients We conducted a survey of 54 subjects with AA universalis treated with the protocol of the Trichology Unit of our Department. Control group comprised 10 subjects who received injections of 0.5 mg/cm2 of triamcinolone acetonide (TAC) in their eyebrows and 1 mg/cm2 of TAC injections in affected scalp. The treatment group included 44 subjects who received the same treatment as the control group in scalp and eyebrows but they also applied a drop of latanoprost 0.005% (50 μg/mL) ophthalmic solution in their eyelid margins every night. Subjects were reviewed every 3 months for 2 years. Results Forty subjects finished the study and four subjects were lost to follow‐up. In the treatment arm of this study, the course was well tolerated and uncomplicated. Both investigators and patients evaluated the regrowth. The results we obtained were: complete regrowth in 17.5%, moderate regrowth in 27.5%, slight regrowth in 30% and without response in 25%. Moderate and total regrowth constituted a cosmetically acceptable response. The therapy was continuous and the response remained without any side effects. No patients had cosmetically acceptable eyelash regrowth in the control group. Conclusions Latanoprost may be an effective drug in the treatment of eyelash AA because it induces acceptable responses (total and moderate) in 45% of the patients. A formal, blinded prospective unilateral controlled study will permit further understanding about this promising therapeutic agent for eyelash AA.  相似文献   
98.
In 1992–94 we screened 6315 students for coeliac disease (CD) by testing antigliadin antibodies (AGA) as the first-level investigation. We found 28 biopsy-proven coeliac patients who were invited to start the gluten-free diet (GFD). The aim of this study was a clinical and laboratory follow-up in these screening–detected coeliac adolescents. Patients were 17 females and 11 males with a mean age at diagnosis of 12.8 ± 1 years (range 11–14). Mean follow-up duration time was 23 ± 7 months (range 9–37). Twenty-three of the 28 screening-detected coeliac patients came to the control visit, 3 refused the follow-up and 2 subjects were not found. Twelve patients (52.2%) stated that they never ate any gluten-containing food, while 11 of them (47.8%) reported occasional transgressions to the diet. GFD acceptance was reported as good ( n = 6), moderate ( n = 11) or low ( n = 6). After starting the GFD, signs of improvement were seen in most patients, such as weight gain, increased height velocity and increased feeling of well-being. AGA (both IgG and IgA classes) and antiendomysium antibodies (AEA) were normal in 19 subjects, 2 cases had IgG-AG A and AEA positivity, 1 patient showed abnormal AGA and AEA levels, while isolated IgA-AGA positivity persisted in 1 case. This study shows that even silent CD cases can clinically benefit from the GFD. The consequences of occasional transgressions to the GFD remain unclear.  相似文献   
99.
Fifteen patients with infantile bone and joint infections were studied immunologically and clinically, 3 at the time of illness and 12 later. Abnormality of immunoglobulins, or complement, or phagocytes was found in 9 patients; 6 were within normal limits for the tests undertaken. Immunodeficiency is probably responsible for the subdued clinical signs of infection and for delayed diagnosis in some patients. It was also related to the extent of femoral head damage in infective arthritis of the hip and to the incidence of wound infection in late elective surgery.  相似文献   
100.
Thukral C  Cheifetz A  Peppercorn MA 《Drugs》2006,66(16):2059-2065
Infliximab, the chimeric monoclonal antibody directed against tumour necrosis factor (TNF)-alpha, has profoundly changed therapy for Crohn's disease (CD). However, for ulcerative colitis (UC), before the publication of ACT 1 and ACT 2 (Active Ulcerative Colitis Trials 1 and 2), there were only a few open-label and controlled trials that evaluated the role of infliximab in the treatment of UC. Results from these earlier studies were equivocal and ambiguous. However, the ACT 1 and ACT 2 trials were large, randomised and placebo-controlled, and have shown that infliximab is significantly more efficacious than placebo in treating both corticosteroid-responsive and -refractory moderate to severe UC. Data from these two studies showed that in patients with moderate to severe UC, treatment with infliximab (5 and 10 mg/kg), compared with placebo, led to significantly higher rates of clinical response, clinical remission and mucosal healing. However, a significant proportion of patients who were receiving oral corticosteroids at the start of the trials, remained on corticosteroids despite infliximab therapy. Additionally, the safety profile of the drug was found to be similar to what has been reported in clinical studies of infliximab in patients with CD.On the basis of currently available data, we use infliximab as a remission-inducing agent in patients who have moderate to severe UC and are either refractory to or intolerant of mesalazine (5-ASA) products and immunomodulators. Moreover, infliximab seems to be a reasonable therapeutic modality for remission maintenance in those patients with UC in whom mesalazine products and immunomodulators have failed. Although data are limited, infliximab may be considered as a remission-inducing agent in patients with moderate to severe UC which is refractory to oral corticosteroids. However, the role of infliximab in the treatment of UC patients who are dependent on oral corticosteroids is still unclear and, therefore, should be considered only in patients who cannot be successfully transitioned to or are intolerant of oral immunomodulators. Furthermore, infliximab may be an alternative to ciclosporin (cyclosporin) in hospitalised patients with severe to moderately severe but not fulminant UC who do not respond to intravenous corticosteroids. At present, there is insufficient evidence to advocate using infliximab as a first-line agent for UC patients with mild or moderate to severe disease. Future randomised, controlled trials with clearly defined patient populations should further help to clarify the definitive role of infliximab in the therapeutic scheme for UC.  相似文献   
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