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排序方式: 共有279条查询结果,搜索用时 248 毫秒
1.
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
2.
Measurement of heparin ex vivo is usually with reference to standard curve prepared with a "spiked" normal human plasma pool (NHP). When the calibration curve was prepared by addition of heparin to whole blood before plasma separation, although the linear relationship was maintained the slope was increased in comparison to the classical standard calibration curve. It is concluded that the preparation of the calibration curve by addition of heparin to NHP may give erroneously high heparin levels in treated patients' plasma, leading perhaps to inappropriate dosage. It was also observed that when heparin was added to blood of different haematocrit (prepared by addition of washed RBC to plasma) and plasma prepared, the subsequent APTT was decreased with the fall in haematocrit; suggesting that the laboratory monitoring of heparin treatment should take into account the patient's haematocrit. 相似文献
3.
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
4.
Is fecundability associated with month of birth? An analysis of 19th and early 20th century family reconstitution data from The Netherlands 总被引:1,自引:4,他引:1
Smits LJ; Van Poppel FW; Verduin JA; Jongbloet PH; Straatman H; Zielhuis GA 《Human reproduction (Oxford, England)》1997,12(11):2572-2578
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
5.
Timmann C Fuchs S Thoma C Lepping B Brattig NW Sievertsen J Thye T Müller-Myhsok B Horstmann RD 《Genes and immunity》2004,5(4):256-260
Since interleukin (IL)-10 is a key mediator of immunosuppression, and immunosuppression is considered an important element of helminth infection, we studied variants of the putative IL-10 gene promoter in 337 individuals from 130 families heavily exposed to infection by the tissue nematode Onchocerca volvulus. As shown by transmission disequilibrium tests, variants of the IL-10 promoter at positions -1082(G/A), -819(C/T), and -592(C/A) in the haplotype of ATA were significantly associated with high peripheral blood cell (PBC) proliferative responses to O. volvulus antigen (OvAg). No associations were observed using phytohemagglutinin-induced PBC proliferation or with qualitative or quantitative phenotypes of onchocerciasis or onchocerciasis-related skin disease. The findings are compatible with the hypothesis that the ATA haplotype causes a decrease in IL-10 production by OvAg-reactive type-1 regulatory T-lymphocytes, thereby alleviating the suppression of other T cells. To our knowledge, this is the first time that an influence of IL-10 promoter variants is shown on the adaptive immune response. 相似文献
6.
7.
Yuli R Tak Rinka MP Van Zundert Rowella CWM Kuijpers Boukje S Van Vlokhoven Hettie FW Rensink Rutger CME Engels 《BMC public health》2012,12(1):21
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8.
Factors that affect human hemopoiesis are produced by T-cell growth factor dependent and independent cultured T-cell leukemia-lymphoma cells 总被引:3,自引:0,他引:3
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
9.
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
10.
Thye Foo Choo Mohamad Amran Mohd Salleh Kuan Ying Kok Khamirul Amin Matori Suraya Abdul Rashid 《Materials》2020,13(22)
Grog is an additive material that plays important roles in ceramic making. It improves the fabrication process of green bodies as well as the physical properties of fired bodies. Few low-cost materials and wastes have found their application as grog in recent years, thus encouraging the replacement of commercial grogs with cost-saving materials. Coal fly ash, a combustion waste produced by coal-fired power plant, has the potential to be converted into grog owing to its small particle sizes and high content of silica and alumina. In this study, grog was derived from coal fly ash and mixed with kaolin clay to produce ceramics. Effects of the grog addition on the resultant ceramics were investigated. It was found that, to a certain extent, the grog addition reduced the firing shrinkage and increased the total porosity of the ceramics. The dimensional stability of the ceramics at a firing temperature of 1200 °C was also not noticeably affected by the grog. However, the grog addition in general had negative effects on the biaxial flexural strength and refractoriness of the ceramics. 相似文献