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91.
92.
OBJECTIVES: To determine the utility of single-stranded conformation polymorphism (SSCP) analysis for mutation screening in the BTK (Bruton's tyrosine kinase) gene, we investigated 56 X-linked agammaglobulinemia (XLA) families. To obtain genotype/ phenotype correlations, predicted protein aberrations were correlated with the clinical course of the disease. PATIENTS: This study included 56 patients with XLA, with or without a positive family history, who were diagnosed on the basis of their clinical features, low peripheral B-cell count, and low immunoglobulin levels. Ten patients with isolated hypogammaglobulinemia and 50 healthy males served as controls. METHODS: SSCP analysis was performed for the entire BTK gene, including the exon-intron boundaries and the promoter region. Structural implications of the missense mutations were investigated by molecular modeling, and the functional consequences of some mutations also were evaluated by in vitro kinase assays and Western blot analysis. RESULTS: We report the largest series of patients with XLA to date. All but 5 of the 56 index patients with XLA screened with SSCP analysis showed BTK gene abnormalities, and in 2 of the 5 SSCP-negative patients, no BTK protein was found by Western blot analysis. There were 51 mutations, including 37 novel ones, distributed across the entire gene. This report contains the first promoter mutation as well as 14 novel missense mutations with the first ones described for the Tec homology domain and the glycine-rich motif in the SH1 domain. Each index patient had a different mutation, except for four mutations, each in two unrelated individuals. This result supports the strong tendency for private mutations in this disease. No mutations were found in the controls. CONCLUSIONS: Our results demonstrate that molecular genetic testing by SSCP analysis provides an accurate tool for the definitive diagnosis of XLA and the discrimination of borderline cases, such as certain hypogammaglobulinemia or common variable immunodeficiency patients with overlapping clinical features. Genotype/ phenotype correlations are not currently possible, making prediction of the clinical course based on molecular genetic data infeasible.  相似文献   
93.
Changes in kinematics as a function of lifting weight and frequency was investigated in sagittal symmetric repetitive lifting. For every lift cycle (lowering and lifting) the motion range between the upright position (0 degrees ) and the maximum angular displacement of the thigh and lower-trunk body segments was recorded. Ten subjects performed five repetitive lifting bouts with different weight/frequency combinations, using both stoop and squat lifting techniques. In total, 6384 lifts were analysed. The lifting weight or frequency did not influence the motion ranges in stoop lifting. In squat lifting the weight lifted did not appear to have any influence on the motion ranges, while the thigh motion range was significantly smaller at lifting frequency of 20 lifts min(-1) than at a frequency of 10. A significant gradual decrease in the thigh motion range and corresponding increase in the lower-trunk motion range were seen for a majority of the subjects during squat lifting at frequency 20. These changes suggest that quadriceps muscle strength is the limiting factor in repetitive squat lifting. Also the variation in motion ranges was greater in squat lifting than in stoop lifting. RELEVANCE: Forestry work involves frequent lifting. However, compliance in using squat lifting technique, which is recommended for safe lifting, is sometimes poor. Fatigue may be one of the determinants for changes in kinematics and choice of technique in lifting tasks.  相似文献   
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Aim: The suckling neonates and infants are reliant primarily on the mother for optimal supply of docosahexaenoic acid (DHA). The richest source of preformed DHA is cold‐water oily fish. Although there is paucity of data, existing evidence suggest women with restricted access to these foods have low or marginal DHA status. The aim of the study was to investigate milk fatty acids of Sudanese mothers whose traditional diet is high in carbohydrate and low in fat and gain some insight into the provision of DHA to the suckling offspring. Methods: Colostrum (n = 26), transitional (n = 20) and mature (n = 14) milk samples were obtained from Northern Sudanese women (NSW) recruited prior to delivery from Ibrahim Malik and Khartoum Teaching Hospitals. Results: The arachidonic acid content of the colostrum (0.87 ± 0.28%) and transitional (0.89 ± 0.29%) and mature (0.48 ± 0.12%) milk of the NSW were broadly comparable with published international values. In contrast, the DHA level (colostrum 0.13 ± 0.07%, transitional 0.13 ± 0.06% and mature milk 0.06 ± 0.05%) was very low. Conclusion: The study reveals breast milk of NSW, whose traditional diet is almost devoid of fish and fish products, is unlikely to provide sufficient DHA to support optimal postnatal neuro‐visual development.  相似文献   
96.
Seven patients with refractory lymphomas underwent marrow reconstitution with peripheral blood stem cells (PBSCs) harvested by large-volume leukapheresis (LVL). PBSCs were collected from all patients more than 1 month after the last cycle of chemotherapy, and no patient received growth factors. The median number of LVL procedures performed per patient was 4.5, with a mean volume of 24.5 L of blood processed per procedure to obtain 7 x 10(8) mononuclear cells per kg. Autologous PBSCs and platelets were frozen at a controlled rate in plasma and 10-percent dimethyl sulfoxide and stored in the vapor phase of liquid nitrogen. This group of patients was compared to a control group (n = 18) who received medullary marrow (MM) transplants for the same diagnoses under the same protocols during the same period. Posttransplant days to white cell engraftment (PBSC = 17, MM = 15.5) were no different. Days to platelet independence were significantly longer in the LVL PBSC group (PBSC = 33, MM = 16; p < 0.05). This pattern of engraftment is typical of patients treated in this manner. Although Day 0 platelet counts (PBSC = 75.5 x 10(9)/L, MM = 85 x 10(9)/L) and total single-donor unit platelet use (PBSC = 8, MM = 9) were no different, Day 1 platelet counts (PBSC = 128 x 10(9)/L, MM = 61.5 x 10(9)/L; p < 0.05) and Day 14 platelet use (PBSC = 5, MM = 8; p < 0.05) were significantly different, because of the transfusion of cryopreserved autologous platelets with PBSCs on Day 0.  相似文献   
97.
Decreases in glial cell density and in GFAP mRNA in the anterior cingulate cortex have been reported in schizophrenia, bipolar disorder and major depressive disorder. Our study examines astrocyte and oligodendrocyte density in the white and grey matter of the subgenual cingulate cortex, and at the midline of the genu of the corpus callosum, in schizophrenia, bipolar disorder, depression and normal control cases. Serial coronal sections were stained with H and E for anatomical guidance, cresyl haematoxylin for oligodendrocyte identification and GFAP immunohistochemistry for astrocyte identification. Oligodendrocyte and astrocyte density was measured using systematic anatomical distinctions and randomised counting methods. A significant decrease in astrocyte density was observed in schizophrenia compared with normal controls in the cingulate grey matter, cingulate white matter and the midline of the corpus callosum (p = 0.025). Bipolar disorder and depression cases showed no significant changes in astrocyte density. Oligodendrocytes did not show any changes between diagnostic groups. In subgenual cingulate cortex, the ratio of oligodendrocytes to astrocytes was decreased between the controls and the three disease groups, suggesting a specific glial cell type specific change in schizophrenia.  相似文献   
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Background

Impact of non-pharmacological innovations on cancer cure rates is difficult to assess. It remains unclear, whether outcome improves with 2- [18-F]-fluoro-2-deoxyglucose-positron emission tomography and integrated computer tomography (PET/CT) and intensity-modulated radiotherapy (IMRT) for curative treatment of advanced pharyngeal carcinoma.

Patients and methods

Forty five patients with stage IVA oro- or hypopharyngeal carcinoma were staged with an integrated PET/CT and treated with definitive chemoradiation with IMRT from 2002 until 2005. To estimate the impact of PET/CT with IMRT on outcome, a case-control analysis on all patients with PET/CT and IMRT was done after matching with eighty six patients treated between 1991 and 2001 without PET/CT and 3D-conformal radiotherapy with respect to gender, age, stage, grade, and tumor location with a ratio of 1:2. Median follow-up was eighteen months (range, 6–49 months) for the PET/CT-IMRT group and twenty eight months (range, 1–168 months) for the controls.

Results

PET/CT and treatment with IMRT improved cure rates compared to patients without PET/CT and IMRT. Overall survival of patients with PET/CT and IMRT was 97% and 91% at 1 and 2 years respectively, compared to 74% and 54% for patients without PET/CT or IMRT (p = 0.002). The event-free survival rate of PET/CT-IMRT group was 90% and 80% at 1 and 2 years respectively, compared to 72% and 56% in the control group (p = 0.005).

Conclusion

PET/CT in combination with IMRT and chemotherapy for pharyngeal carcinoma improve oncological therapy of pharyngeal carcinomas. Long-term follow-up is needed to confirm these findings.  相似文献   
100.
The prognostic importance of patient pretreatment clinical and laboratory features was investigated in a group of 303 patients with Philadelphia chromosome-positive benign-phase chronic myelogenous leukemia. Intensive chemotherapy was given to 97 patients, and 78 underwent an early elective splenectomy. The overall median survival time, dated from hospital admission, was 39 months. Patient characteristics associated with shortened survival were age 60 years or older, black race, the presence of hepatomegaly, splenomegaly, symptoms, weight loss, and poor performance status. Adverse blood and bone marrow parameters were anemia, thrombocytosis or thrombocytopenia, a high proportion of peripheral blasts plus promyelocytes or of basophils, a high proportion of marrow blasts or basophils, decreased marrow megakaryocytes, and cytogenetic abnormalities in addition to the Philadelphia chromosome. Several of these factors were interrelated. A multivariate regression analysis demonstrated that the combination blood basophilia, race, additional cytogenetic abnormalities, age and marrow basophilia had the strongest predictive relationship to survival time. This resulted in a model segregating patients into low-, intermediate-, and high-risk groups, with median survivals of 53, 39, and 25 months, respectively. Another model was derived that did not include the marrow features and identified splenomegaly and platelet counts as adding to the prognosis prediction by blood basophilia, race, and age. Evaluation of the effect of therapy, after adjusting for differences in prognostic characteristics, showed that intensive chemotherapy was associated with survival prolongation among patients at intermediate and high risk of death. We conclude that a combination of pretreatment factors identifies different risk subcategories in patients with chronic myelogenous leukemia and is helpful in assessing overall prognosis and treatment effect.  相似文献   
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