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排序方式: 共有209条查询结果,搜索用时 62 毫秒
1.
We report a 24-year-old male with an unusual combination of two inherited neuromuscular disorders – Charcot-Marie-Tooth (CMT) disease type 1A and Duchenne muscular dystrophy (DMD). A phenotypic presentation of this patient included features of both these disorders. Nerve conduction studies revealed demyelinating peripheral neuropathy. Electromyography showed a profound myogenic pattern. The serum creatine kinase level was highly elevated. Muscle biopsy revealed a dystrophic picture with deficient dystrophin immunostaining. CMT1A duplication on chromosome 17p11.2 was found. The frame-shift mutation c.3609–3612delTAAAinsCTT (p.K1204LfsX11) was detected in the dystrophin gene by analysing mRNA isolated from the muscle tissue. The patient inherited both these mutations from his mother. The combination of CMT1A and DMD has not been reported as yet.  相似文献   
2.
BACKGROUND: Many patients with asthma or chronic obstructive pulmonary diseaseuse their medication inhalers incorrectly. General practitioners,pharmacists and other health care providers do not always havethe opportunity to instruct patients in correct inhaler technique. OBJECTIVE: To find out whether the inhaler technique and respiratory symptomsof patients can be improved after instruction by practice assistants. METHODS: Single blind, randomized intervention study in which 48 patientswho had been using a dry powder inhaler for at least one monthtook part. Their inhaler technique was videotaped on two visitswith a two-week interval between visits. The inhaler techniqueon the videos was subsequently scored by two experts on ninecriteria. At both visits the patients completed a questionnaireabout their respiratory symptoms. After the first video, 25patients were randomly chosen to receive instruction from oneof six practice assistants who had followed a one evening courseabout inhaler instruction, and who had been issued an instruction-set. RESULTS: The patients who received instruction had a significantly greaterreduction in number of mistakes at the second visit than thepatients who did not (P = 0.01). The instructed patients alsoreported less dyspnoea at the second visit (P = 0.03). No effectof instruction was found on wheezing, cough and sputum production. CONCLUSION: The inhaler technique of patients can be improved significantlyby the instruction of patients by trained practice assistants,possibly resulting in less dyspnoea. Keywords. Administration-inhalation, obstructive lung diseases, airways symptoms, patient-education, general practice.  相似文献   
3.
PURPOSE: The use of systemic corticosteroids for the management of acute exacerbation of chronic obstructive pulmonary disease (AECOPD) was studied. METHODS: Medical charts of patients admitted to the hospital between July 2002 and November 2003 with a primary diagnosis of AECOPD were retrospectively reviewed. The primary objective was to characterize the drug, dosage, route, frequency, and duration of systemic corticosteroids prescribed for the management of AECOPD. The secondary objective was to compare the mean length of stay (LOS) and 30-day relapse rate between patients who received lower and higher dosages of corticosteroids. RESULTS: One hundred forty-five admissions (123 patients) for AECOPD (mean +/- S.D. age, 65 +/- 11 years) were evaluated. Higher dosages of systemic corticosteroids (>80 mg of prednisone equivalent [PE] per day) were prescribed for 51% and i.v. therapy for 56% of admissions. The mean +/- S.D. total systemic corticosteroid exposure during hospitalization for all admissions was 759 +/- 971 mg of PE (mean +/- S.D. daily exposure = 134 +/- 111 mg of PE per day). The mean LOS was significantly longer for the higher-dosage group than for the lower-dosage group (6.1 versus 4.2 days, p = 0.0004). A tapered regimen was prescribed for 79% of discharges. Twenty-seven percent of the discharges with routine follow-up care had a relapse of disease within 30 days. CONCLUSION: This retrospective observational study confirmed a wide variability in the dosages of systemic corticosteroids for the inpatient management of AECOPD, including the use of higher dosages and tapered regimens. Prospective randomized studies are needed to determine the most effective regimen of systemic corticosteroids in patients with AECOPD.  相似文献   
4.
Molecular genetic characterization of XRCC4 function   总被引:2,自引:0,他引:2  
XRCC4 is a generally expressed protein of 334 amino acids that is involved in the repair of DNA double-strand breaks and in V(D)J recombination, but its function is unknown. In this study, we have used a mutational approach and the yeast two-hybrid method to perform an initial characterization of this protein. We show that the XRCC4 protein is located in the nucleus. We also demonstrate that several potential phosphorylation sites are not required for XRCC4 function in a transient V(D)J recombination assay. In addition, we show that XRCC4 forms a homodimer in vivo with the homodimerization domain being located within amino acids 115-204. Finally, we define a core domain of XRCC4 that functions in V(D)J recombination and comprises amino acids 18-204. Potential functions of XRCC4 are discussed.   相似文献   
5.
The relationship between fecundability and month of birth was investigated in a cohort of 1526 women who married between 1802 and 1929, using only women whose first marriage occurred before the age of 35 years. On the basis of their time to pregnancy (TTP, calculated as time between wedding and first birth minus gestational length), women were categorized into two groups: fecunds (TTP up to 12 months or prenuptial conceptions, n = 1348) and subfecunds (TTP >18 months, n = 118). By use of logistic regression, cosinor functions with a period of 1 year or 6 months and variable shift and amplitude were fitted through the monthly odds of subfecunds versus fecunds. The best fitting curve was unimodal, with a zenith in September (P = 0.13 for H0: no differences). Exclusion of childless women (n = 36, minimum follow-up 5 years) from the subfecunds led to a similar curve (P < 0.01), while childless women, as compared with fecunds, showed a birth distribution that was best represented with a bimodal curve with zeniths in January and July (P = 0.06). This study provides evidence for the existence of differences in fecundability by month of birth. The cause of this relationship is unclear, but may lie in a melatonin-dependent circannual variability of the quality of the oocyte.   相似文献   
6.
BACKGROUND: Neuromuscular weakness in paediatric patients with sepsis and multiple organ dysfunction is increasingly reported. However, many aspects of neuromuscular involvement in critically ill children are not completely understood. As more patients survive the critical illness, an understanding of the long-term outcomes of this condition is needed. AIMS: To describe clinical and electrophysiological features and evaluate the long-term outcomes in critically ill paediatric patients with neuromuscular complications. METHODS: A case series of five critically ill children was observed prospectively for a 1-month period. Selected clinical and laboratory parameters were evaluated. Electrophysiological studies were performed during the first week and then 1 month later in order to detect signs of critical illness polyneuromyopathy (CIPM). Patients with neuromuscular involvement completed a 1-year follow-up. RESULTS: Electrophysiological abnormalities were detected in two patients. Flaccid quadriplegia was a clinical presentation. Both children had electromyographic evidence of chronic partial denervation at follow-up, findings indicative of a preceding axonal neuropathy. Marked but incomplete recovery within 1 year after the onset of the disease occured in both patients. With a mild residual functional handicap the health-related quality of life was not significantly impaired (Barthel Index > 80). CONCLUSIONS: In both our patients with CIPM, the long-term clinical outcome is markedly better than we expected when electromyography in the 1-year follow-up demonstrated a persistent severe chronic partial denervation. These findings can have important implications for the management and rehabilitation of paediatric intensive care survivors.  相似文献   
7.
PURPOSE: The causes, prevention, and treatment of osteoporosis in specific populations are discussed. SUMMARY: Osteoporosis and osteopenia affect 44 million women and men ages 50 years or older. Fractures are the most devastating consequence of this disease and significantly affect quality of life, activities of daily living, survival, and health care costs. Most osteoporosis research has focused on postmenopausal women, but several other populations are at risk for osteoporosis, such as patients taking certain medications that affect bone health and those with various health conditions that cause bone loss, including anorexia nervosa, hyperthyroidism, organ transplantation, chronic obstructive pulmonary disease, and inflammatory bowel disease. Glucocorticoids are the most common secondary cause of osteoporosis. Other medications that have been implicated as secondary causes include anticonvulsants, heparin, warfarin, and methotrexate. Preventing osteoporosis may be even more important in adolescence than after menopause. CONCLUSION: Osteoporosis needs to be recognized, monitored, and appropriately treated in patients taking medications that affect bone health and in patients with conditions that increase the risk of osteoporosis.  相似文献   
8.

Background  

The incidence of depressive symptoms increases during adolescence, from 10.0% to 24.5% at age 11 to 15, respectively. Experiencing elevated levels of depressive symptoms increases the risk of a depressive disorder in adulthood. A universal school-based depression prevention program Op Volle Kracht (OVK) was developed, based on the Penn Resiliency Program, aimed at preventing the increase of depressive symptoms during adolescence and enhancing positive development. In this study the effectiveness of OVK will be tested and possible mediators of program effects will be focus of study as well.  相似文献   
9.
Tarella  C; Ruscetti  FW; Poiesz  BJ; Woods  A; Gallo  RC 《Blood》1982,59(6):1330-1336
Some laboratory results and clinical situations suggest that human T cells may be important in the regulation of growth of hematopoietic cells. Since the discovery of T-cell growth factor (TCGF), systems are now available for the long-term specific in vitro propagation of mature normal or neoplastic human T cells, providing an opportunity to study the influence of T cells on hematopoiesis. Recently, 24 cell lines from patients with cutaneous T-cell lymphoma (CTCL) and T-cell acute lymphoblastic leukemia (T-ALL) were grown with TCGF and then assessed for release of humoral factors that affect hematopoiesis. Conditioned media (CM) from these cell lines were tested for erythroid burst- promoting activity (BPA) and granulocyte colony-stimulating activity (CSA). BPA was detected in CM from 3/6 cultures of T-ALL patients and 4/6 CTCL cultures. CSA was found in the CM from 6/8 cultures of T-ALL patients, 7/12 CTCL cultures, and 3/4 CTCL cell lines that become independent of exogenous TCGF for growth. The CSA from several of the neoplastic T-cell cultures stimulated high levels of eosinophil colonies, a possible source of the eosinophilia seen in these patients. The ability of continuously proliferating human T lymphocytes, which retain functional specificity and responsiveness to normal humoral regulation, to produce factors that directly or indirectly stimulate myeloid and erythroid colony formation lends further credence to the role of T lymphocytes in regulating hematopoiesis.  相似文献   
10.
Eastment  CE; Ruscetti  FW 《Blood》1982,60(4):999-1006
In long-term hamster bone marrow cultures, proliferation and differentiation of hemopoietic stem cells occurs for several months without need for hydrocortisone or adherent stromal elements, which are requirements for bone marrow growth in all other species studied. Only the most primitive erythroid progenitors (BFU-E) are produced in the cultures. Following treatment of the cells with erythropoietin, these progenitor cells undergo differentiation into mature hemoglobinized red blood cells. Concomitant addition of erythropoietin (Epo) and prostaglandin-E1 (PGE1) results in the production of large numbers of maturing red blood cells. In cultures stimulated with Epo and PGE1, as many as 70% of the cells are benzidine-positive, while Epo alone stimulated as many as 45% of the cells to become erythroid. Epo and PGE1 do not have any apparent deleterious effect on the continuous hemopoiesis occurring in these cultures. Under identical conditions, syngeneic adherent cell cultures do not produce any erythroid elements. The development of mature red blood cells from primitive erythroid precursors occurs in the presence of Epo alone and without any apparent need for adherent stromal elements. These cultures provide a useful in vitro model for dissecting the positive and negative signals that regulate erythropoiesis.  相似文献   
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