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161.
The release of metoclopramide hydrochloride (a water-soluble cationic drug) and diclofenac sodium (a sparingly soluble anionic drug) from pellets coated with ethylcellulose from an aqueous ethylcellulose dispersion (Surelease) at different coating loads was investigated. The release rates of each drug decreased as the coating load of Surelease increased. However, despite its lower water solubility, diclofenac sodium was released slightly faster than metoclopramide hydrochloride at equivalent coating loads. Changes in the release rates after curing were more pronounced for metoclopramide hydrochloride and the release rates of diclofenac sodium were lower than those of metoclopramide hydrochloride after curing. Differences between the release behaviour of the two drugs were probably due to an interaction between the cationic metoclopramide and the anionic ammonium oleate present in the Surelease. The slower release of metoclopramide hydrochloride may be due to an in situ formation of a poorly soluble complex of the drug and the ammonium oleate. This complex, because of its large molecular size, may diffuse more slowly through the film, causing a reduction in the release rate of metoclopramide hydrochloride. This interaction may also account for the differences in release characteristics of the drugs after curing. During curing the surfactant, due to its unstable nature in heat, may be converted to its constituent components. The interaction of drug with the surfactant was reduced as the residue of the ammonium oleate decreased during curing. However, a relatively low volume flow rate of air, and therefore, slower removal of ammonia in the modified side-vented Manesty Accela-cota 10 may also have affected the coating process of the pellets.  相似文献   
162.
Production of monoclonal antibodies to HLA-G, a nonpolymorphic antigen of non-classical HLA class I, is of basic and clinical importance. In the present study, monoclonal antibodies were prepared which recognize different membrane bound and soluble isoforms of HLA-G, following immunization of BALB/c mice with a synthetic peptide. Use of this peptide (23 residues), which is present in the alpha1 domain of HLA-G, was previously demonstrated to provide antibodies useful for recognition of HLA-G isoforms in human placenta. Antibody-producing hybridomas were screened by an indirect one-step ELISA method. A clone designated 5E6H7, secreted antibodies useful in immunostaining studies involving both surface HLA-G of placental tissues and soluble forms of this antigen in human sera. In addition, unreactivity of this antibody with human lymphocytes and sections of normal human skin was observed by immunofluorescence microscopy, thus demonstrating its specificity for HLA-G.  相似文献   
163.
SUMMARY:   We present four adult cases of acute renal failure associated with hypothyroidism. All patients presented with symptoms suggestive of moderate to severe hypothyroidism, such as cold intolerance, constipation, muscle weakness, and lower extremity oedema. Initial serum creatinine levels ranged between 115 and 203 µmol/L (1.3 and 2.3 mg/dL), with creatinine clearances (CrCl) ranging between 0.58 and 0.97 mL/s (34.5 and 58 mL/min). After 6–12 weeks of treatment with levothyroxin, serum creatinine levels decreased to the range of 80 and 124 µmol/L (0.9 and 1.4 mg/dL) and CrCl increased to 0.74–1.64 mL/s (44–98 mL/min). One patient had proteinuria of 800 mg/day, which decreased to the normal range (<200 mg/day) after levothyroxin treatment. One patient developed acute gouty arthritis before normalization of thyroid-stimulating hormone (TSH), which was successfully managed with prednisone therapy. All of our patients had increased creatine kinase (CK), ranging between 1000 and 2360 U/L (normal range, 22–165 U/L), which normalized after 6 weeks of levothyroxin treatment.  相似文献   
164.
The generation of new knowledge through research can contribute significantly to the improvement of services for individuals with intellectual and developmental disabilities. This study extends a previous study by Sigafoos, Roberts, and Couzens [Aust. N.Z. J. Dev. Disabil. 17 (1991) 331] by examining research productivity in intellectual and developmental disability in Australian journals for 1990-1999. Institutions that published research articles on intellectual and developmental disabilities in Australian journals in the 1990s were identified by noting the affiliations of authors. The most productive institutions were primarily universities in Australia and the United States of America. Publication trends in the decade of the 1990s are compared with trends of the previous decade (1980-1990).  相似文献   
165.
The objective of this study was to test the reliability and validity of the Iranian version of the European Organization for Research and Treatment of Cancer (EORTC) Quality of Life Questionnaire (QLQ-C30). The English-language version of the questionnaire was translated into Persian (Iranian language), and its final form was approved by the EORTC Study Group on Quality of Life before it was used in this study. The questionnaire was administered at two time points to a consecutive sample of 168 newly diagnosed breast cancer patients, and almost all of them (99%) found the questions easy to understand and acceptable. Crohnbach's alpha coefficient for multi-item scales (to test reliability) ranged from 0.48 to 0.95 at baseline and from 0.52 to 0.98 at follow-up administration of the questionnaire. Validity was checked using two methods: inter-scale correlation and known-groups comparison. Almost all inter-scale correlations were statistically significant in the expected direction. Known-groups comparison analysis showed that all functioning and symptom scales discriminated between subgroups of patients differing in clinical status as defined by their performance status and disease stage. In general, the findings of this study indicate that the Iranian version of the EORTC QLQ-C30 is a reliable and valid measure of quality of life in cancer patients and can be used in clinical trials and studies of outcome research in oncology.  相似文献   
166.
167.
Background:  Hair counts were studied in scalp biopsy specimens of androgenetic alopecia (AGA) in male and female patients. We also assessed the normal value of hair count in scalp biopsy specimen from Iranians and compared with published data.
Methods:  Thirty subjects with clinically normal scalps, 25 male and 28 female patients with AGA were studied. Vertical and horizontal sections of 4-mm punch biopsy specimens were examined at various levels from the papillary dermis to the subcutis. Hair counts of total, terminal, vellus, anagen and telogen hairs were obtained by ocular micrometer.
Results:  Hair counts were not significantly different from published data in American Whites but significantly higher in Iranians compared with Koreans (p < 0.001). There was no significant difference between male and female patients with AGA. Perifollicular inflammation was lower in both the normal subjects and the patients compared with other studies.
Conclusion:  In AGA patients, total and vellus hairs were lower and terminal to vellus (T:V) ratio was higher than the results of previous studies in Whites (p < 00.1). T:V ratio of control group was significantly higher in this study compared with previous published data. Perhaps the higher ratio than the reported data could means the onset of miniaturization.  相似文献   
168.
Tamoxifen is the most common antiestrogen used in the treatment of estrogen-positive breast cancer but its adverse effects and also resistance to this drug are serious challenges in the treatment of breast cancer. Characterization of mechanisms responsible for these adverse effects can lead to design of more efficient therapeutic strategies for the treatment of breast cancer. Here, we used a cellular model to evaluate the effects of autocrine expression of human growth hormone on responses of cells to tamoxifen. Our results imply for the first time that autocrine expression of growth hormone in human breast adenocarcinoma cell line, MCF-7, results in increase in cell proliferative capacity of cells even in the presence of tamoxifen. This effect may be due to up-regulation of G-coupled estrogen receptor, GPR30, which is activated by tamoxifen.  相似文献   
169.

Background  

Intense and long-standing problems in burn centers in Tehran have led nurses to burnout. This phenomenon has provoked serious responses and has put the nurses, patients and the organization under pressure. The challenge for managers and nurse executives is to understand the factors which would reduce or increase the nurses' responses to burnout and develop delivery systems that promote positive adaptation and facilitate quality care. This study, as a part of more extensive research, aims to explore and describe the nurses' perceptions of the factors affecting their responses to burnout.  相似文献   
170.
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