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31.
32.
Insulin receptors on leukemia and lymphoma cells   总被引:1,自引:0,他引:1  
Chen  PM; Kwan  SH; Hwang  TS; Chiang  BN; Chou  CK 《Blood》1983,62(2):251-255
Tumor cells obtained from leukemia and lymphoma patients were investigated for specific insulin receptors. Using radioactive 125I- labeled insulin, specific insulin binding sites were demonstrated on most acute lymphocytic leukemia (ALL) and acute myelocytic leukemia (AML) cells, including acute promyelocytic leukemia (APL), chronic myelocytic leukemia (CML), and acute monocytic leukemia (AMoL) cells. Insulin receptors were not found on chronic lymphocytic leukemia (CLL) and malignant lymphoma (ML) cells. Specific insulin binding sites were also found on monocytes and thymocytes after treatment with phytohemagglutinin (PHA-P), but not on inactivated tonsil cells, peripheral blood lymphocytes, or thymocytes. There was no inverse correlation between the content of insulin receptors and the basal level of circulating insulin. These data suggest that the insulin receptor may be a new marker of acute leukemia and chronic myelocytic leukemia.  相似文献   
33.
34.
Glanzmann thrombasthenia (GT) is an autosomal recessive platelet function disorder characterized by mucocutaneous bleeding as the most common clinical phenotype. Patients with GT have normal platelet counts, platelet morphology but reduced platelet aggregation in response to various agonists. Homozygosity or compound heterozygosity for variants in the ITGA2B/ITGB3 genes is the genetic basis for GT. Establishing a molecular diagnosis is definitive and is important for predictive testing. Using multi-gene panels is an accurate, faster, and cost-effective mode as compared to Sanger sequencing in large genes. We used a targeted resequencing based approach to identify pathogenic variants in eight cases in seven families. These variants were validated using Sanger sequencing in patients as well as family members and were predicted probably pathogenic using in-silico prediction tools. The variants include three missense (3/7 = 43%) (ITGA2B:c.1028 T > C, ITGA2B:c.1186G > A, ITGB3:c.1388G > C), two deletions (ITGA2B:c.559delG, ITGA2B:c.3092delT), one duplication (ITGA2B:c.1424_1427dupAGGT) and nonsense variant (ITGA2B:c.2578C > T, p.Gln860Ter). Except for one case which was compound heterozygous, the rest of the cases were homozygous. We found two novel variants that are reported for the first time in GT. The targeted resequencing based approach revealed varied genetic variants in North Indian patients, including two novels ones. The high yield of our panel indicates its suitability for usage in larger cohorts for the genetic diagnosis of GT patients. This approach is cost-effective and less cumbersome as compared to Sanger sequencing for these large size genes with multiple exons. The information so obtained is helpful in prenatal testing, carrier analysis, and genetic counseling.  相似文献   
35.
When normal volunteers or patients with type I von Willebrand disease (VWD) are given desmopressin (DDAVP), a set of larger-than-normal (supranormal) von Willebrand factor (VWF) multimers, similar to those present in VWF-containing cells such as platelets megakaryocytes and endothelial cells, appear transiently in postinfusion plasma. In two kindreds with mild lifelong bleeding symptoms transmitted as an autosomal dominant trait, all ten symptomatic members (but none of the five asymptomatic members) had a supranormal multimeric structure for plasma VWF, apparently identical to that seen for postdesmopressin normal plasma. Plasma factor VIII coagulant activity (VIII:C), VWF antigen (VWF:Ag), ristocetin-induced platelet agglutination, and ristocetin cofactor (RiCof) activity were low. Platelet VWF:Ag and RiCof levels (tested for three patients only) were normal. Bleeding times were normal or slightly prolonged. The patients' platelet multimeric structure was the same as that for normal platelets. After desmopressin infusion the plasma VWF multimeric structure remained supranormal as for preinfusion plasma, with VIII:C VWF:Ag and RiCof increasing markedly over baseline values and disappearing at a normal rate. Examination of the VWF subunit composition from three of these patients indicated that proteolytic processing of their VWF did not differ from normal. This study describes the first variant of VWD with a supranormal multimeric structure.  相似文献   
36.

Introduction

The acute surgical model has been trialled in several institutions with mixed results. The aim of this study was to determine whether the acute surgical model provides better outcomes for patients with acute biliary presentation, compared with the traditional emergency surgery model of care.

Methods

A retrospective review was carried out of patients who were admitted for management of acute biliary presentation, before and after the establishment of an acute surgical unit (ASU). Outcomes measured were time to operation, operating time, after-hours operation (6pm – 8am), length of stay and surgical complications.

Results

A total of 342 patients presented with acute biliary symptoms and were managed operatively. The median time to operation was significantly reduced in the ASU group (32.4 vs 25.4 hours, p=0.047), as were the proportion of operations performed after hours (19.5% vs 2.5%, p<0.001) and the median length of stay (4 vs 3 days, p<0.001). The median operating time, rate of conversion to open cholecystectomy and wound infection rates remained similar.

Conclusions

Implementation of an ASU can lead to objective differences in outcomes for patients who present with acute cholecystitis. In our study, the ASU significantly reduced time to operation, the number of operations performed after hours and length of stay.  相似文献   
37.
A patient with a lifelong bleeding disorder was diagnosed as having Type II von Willebrand disease. The larger multimers of von Willebrand factor were absent from her plasma but present in platelets. A high- resolution electrophoretic technique was used to study the complex structure of individual von Willebrand factor multimers. In normal plasma, each multimer could be resolved into five bands: a more intense central one and four less intense, two moving faster and two slower than the central band. In normal platelets, each multimer could also be resolved into five bands. The central one had a mobility similar to that in plasma, whereas the four satellite bands had a mobility that differed from that of the corresponding plasma bands. In the patient, platelet von Willebrand factor antigen content and ristocetin cofactor activity were normal, and von Willebrand factor showed the same structure of individual multimers as seen in normal platelets. On the other hand, plasma von Willebrand factor antigen and ristocetin cofactor activity were decreased, and the structure of individual von Willebrand factor multimers was different from that of normal plasma and similar to that seen in normal and patient's platelets. After infusion of 1-deamino-8-D-arginine vasopressin, the largest von Willebrand factor multimers, as well as new satellite bands with a mobility similar to those in normal plasma, appeared in the patient plasma, and the levels of von Willebrand factor antigen and ristocetin cofactor activity became normal. Yet no relevant change in the prolonged bleeding time was observed. This new variant of von Willebrand disease, therefore, is characterized by the presence of a dysfunctional von Willebrand factor molecule that exhibits unique structural abnormalities in plasma but appears to be normal in platelets. The designation of Type IIF is proposed for this type of von Willebrand disease in accordance with the terminology that has been previously used.  相似文献   
38.
The optimal method of reconstruction following mastectomy for breast cancer patients receiving radiation therapy (RT) is controversial. This study evaluated patient satisfaction and complication rates among patients who received implant‐based breast reconstruction. The specific treatment algorithm analyzed included patients receiving mastectomy and immediate temporary tissue expander (TE), followed by placement of a permanent breast implant (PI). If indicated, RT was delivered to the fully expanded TE. Records of 218 consecutive patients with 222 invasive (85%) or in situ (15%) breast lesions from the Salt Lake City region treated between 1998 and 2009 were retrospectively reviewed, 28% of whom received RT. Median RT dose was 50.4 Gy, and 41% received a scar boost at a median dose of 10 Gy. Kaplan–Meier analyses were performed to evaluate the cumulative incidence of surgical complications, including permanent PI removal. Risk factors associated with surgical events were analyzed. To evaluate cosmetic results and patient satisfaction, an anonymous survey was administered. Mean follow‐up was 44 months (range 6–144). Actuarial 5‐year PI removal rates for non‐RT and RT patients were 4% and 22%, respectively. On multivariate analysis (MVA), the only factor associated with PI removal was RT (p = 0.009). Surveys were returned describing the outcomes of 149 breasts. For the non‐RT and RT groups, those who rated their breast appearance as good or better were 63% versus 62%, respectively. Under 1/3 of each group was dissatisfied with their reconstruction. RT did not significantly affect patient satisfaction scores, but on MVA RT was the only factor associated with increased PI removal. This reconstruction technique may be considered an acceptable option even if RT is needed, but the increased complication risk with RT must be recognized.  相似文献   
39.

Background

Quality indicators for primary care focus predominantly on the public health model and organisational measures. Patient experience is an important dimension of quality. Accreditation for GP training practices requires demonstration of a series of attributes including patient-centred care.

Aim

The national GP Patient Survey (GPPS) was used to determine the characteristics of general practices scoring highly in responses relating to the professional skills and characteristics of doctors. Specifically, to determine whether active participation in postgraduate GP training was associated with more positive experiences of care.

Design and setting

Retrospective cross-sectional study in general practices in England.

Method

Data were obtained from the national QOF dataset for England, 2011/12 (8164 general practices); the GPPS in 2012 (2.7 million questionnaires in England; response rate 36%); general practice and demographic characteristics. Sensitivity analyses included local data validated by practice inspections. Outcome measures: multilevel regression models adjusted for clustering.

Results

GP training practice status (29% of practices) was a significant predictor of positive GPPS responses to all questions in the ‘doctor care’ (n = 6) and ‘overall satisfaction’ (n = 2) domains but not to any of the ‘nurse care’ or ‘out-of-hours’ domain questions. The findings were supported by the sensitivity analyses. Other positive determinants were: smaller practice and individual GP list sizes, more older patients, lower social deprivation and fewer ethnic minority patients.

Conclusion

Based on GPPS responses, doctors in GP training practices appeared to offer more patient-centred care with patients reporting more positively on attributes of doctors such as ‘listening’ or ‘care and concern’.  相似文献   
40.
The following abstracts won prizes at the 153rd East Midlands Surgical Society meeting held on 9 November 2012 at Leicester General Hospital. First prize was won by George et al. The paper by Ogunbiyi et al was placed second and the paper by Khanna et al was placed third.  相似文献   
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