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1.
The relationship was studied between preschool and current respiratory symptoms and cough receptor sensitivity in children. Forty six white children aged 7 years were investigated. They were divided into three groups: (i) healthy children; (ii) children with a history of idiopathic cough; and (iii) children with a history of wheezing. Cough receptor sensitivity was assessed by the inhalation of serially increasing concentrations of nebulised citric acid. The concentration which first induced a cough was the cough threshold and was taken as a measure of cough receptor sensitivity. The cough threshold was unrelated to respiratory symptoms, bronchial responsiveness, parental smoking, and atopic status. A wide variation in cough threshold was seen. Although these results suggest that idiopathic cough is unrelated to cough receptor sensitivity as assessed by the citric acid cough threshold, it is unclear whether threshold measurements are an accurate reflection of receptor sensitivity.  相似文献   
2.
Solid and papillary epithelial neoplasms of the pancreas: CT findings   总被引:1,自引:0,他引:1  
Choi  BI; Kim  KW; Han  MC; Kim  YI; Kim  CW 《Radiology》1988,166(2):413-416
Five female patients and one male patient with solid and papillary epithelial neoplasms of the pancreas were examined with computed tomography (CT). The mean age of the patients was 27 years (range, 13-46 years). All cases showed well-encapsulated, round or lobulated masses consisting of both cystic and solid areas. Cystic portions showed CT numbers that suggested hemorrhagic necrosis. There were no internal septations within the masses. In three tumors located in the head of the pancreas, dilatation of the biliary tree was absent or minimal, although the masses were large. Two tumors contained calcifications. One tumor demonstrated metastatic deposits in liver and lymph nodes. Metastatic masses appeared similar to the primary pancreatic mass. Solid and papillary neoplasm of the pancreas should be the primary diagnostic consideration when characteristic CT findings are detected in a young female patient.  相似文献   
3.
Acute porphyria is rare in orientals. We describe a Chinese woman with recurrent generalised tonic-clonic seizures and abdominal pain. Genomic DNA studies identified a heterozygous base substitution from guanine to adenine at nucleotide position 503, resulting in substitution of arginine by histidine at position 168 of the protein (R168H). This genetic abnormality is similar to the mutation reported in Caucasians with variegate porphyria. To the best of our knowledge, this is the first report in the English literature a Chinese patient with variegate porphyria with an identifiable mutation. A brief review of porphyria is presented.  相似文献   
4.
The influence of reported paternal attitudes on the decision to breast-feed   总被引:1,自引:0,他引:1  
Objective: To identify factors that influence a woman's decision to breast-feed.
Methodology: Five hundred and fifty-six women were recruited from the maternity wards of two Perth hospitals. Data were collected from a self-administered questionnaire completed by participants prior to discharge. Logistic regression analysis was used to determine factors influencing the initiation of breast-feeding.
Results: At discharge from hospital 83.8% of women were breast-feeding, including 6% who were giving complementary formula feeds. After controlling for potentially confounding demographic and biomedical factors, the father's reported preference for breast-feeding was found to be the most important factor influencing a woman's decision to breast-feed (OR 10.18).
Conclusion: Fathers participate in and influence the choice of infant feeding method and should be included in breast-feeding discussions.  相似文献   
5.
The Dunning H rat prostate tumor (R3327H) is a widely used experimental model of human prostatic adenocarcinoma (CaP). The Dunning H tumor has been characterized as androgen-sensitive, androgen-receptor (AR) positive, prostate-specific antigen and prostatic acid phosphatase (PAP) positive. To date, the tumor has been maintained by serial passage in vivo because of the lack of an in vitro cell line that retains the characteristics of the in vivo tumor. The objective of the present study was to establish a propagable cell line from R3327H adenocarcinoma that maintained androgen sensitivity and expression of AR, PSA and PAP. Tissue harvested from an in vivo R3327H tumor was dissociated with collagenase and placed into Richter's improved media (with supplements). A cytokeratin-positive epithelial cell line (HUNC- E) and a vimentin-positive stromal cell line (HUNC-S) were generated from the primary culture, subcultured continuously for >300 days, and passaged >50 times. Survival of the HUNC-E cell line in vitro depended on several media supplements, including nicotinamide, insulin, transferrin, selenium and epidermal growth factor (EGF). HUNC-E cells expressed AR and produced PSA and PAP throughout the culture period, as confirmed by immunocytochemistry and Western blot analyses. Addition of 14 nM testosterone (T) or dihydrotestosterone (DHT) to HUNC-E cells, stimulated DNA synthesis as well as anchorage-independent growth and PSA production, which demonstrated the androgen-sensitive nature of the cells in vitro. When HUNC-E and HUNC-S cells were combined in a 3:1 ratio and introduced subcutaneously into syngeneic male hosts, tumors formed in 2/3 animals with an average latency of 7 months. RT-PCR and immunocytochemical characterization of the HUNC cell lines revealed that the cells expressed several growth factors and their cognate receptors, including HGF, TGF-alpha and the TGF-betas, indicating the establishment of potential autocrine loops in the neoplastic cells. The HUNC-E and HUNC-S CaP cell lines, which retain the characteristics of the epithelial and stromal components of the in vivo R3327H tumor, will allow a more thorough and informative molecular and biological analysis of prostatic adenocarcinoma.   相似文献   
6.
银杏叶提取物改善反复脑缺血再灌注小鼠血液流变学的作用   总被引:34,自引:0,他引:34  
目的:研究银杏叶提取物(EGB)改善反复脑缺血再灌注小鼠血液流这的作用。方法:采用反复脑缺血再注模型鼠,应用毛细管微量热沉法和毛细管微量法分别检测血纤维蛋白原含量和红细胞压积数值,并将结果输入全自动血液流变仪得出血浆粘度、血液粘度、血细胞聚集系数,血栓形成系数及微循环滞留时间(MST)。结果:EBG25 ̄100mg/kg均可不同程度地降低Fib、HCT、降低ηb、ηp、ηh,缩小VAL及TWEL,  相似文献   
7.
Nakamura  H; Said  JW; Miller  CW; Koeffler  HP 《Blood》1993,82(3):920-926
p53 mutations are found in a variety of neoplasia. B-immunoblastic lymphoma (BIBL) is a rapidly progressive, aggressive lymphoma. As patients with acquired immunodeficiency syndrome (AIDS) live longer, BIBL is becoming an increasing problem. We asked three questions in our study. What is the frequency of p53 mutations in BIBL? Is it more frequent in patients with AIDS? Can immunohistochemical staining of lymph nodes for expression of p53 substitute for mutational analysis of p53 to detect lymphomas with mutated p53? Exons 5, 6, 7, 8 of the p53 gene (hot-spots for mutations) were amplified and examined for mutations by single-strand conformation polymorphism (SSCP) analysis. Altered migration was observed in 7 of 52 BIBL samples. Of these, 4 of 25 were from individuals infected with human immunodeficiency virus (HIV) and 3 of 27 were not infected with HIV. Direct sequencing of amplified material confirmed the presence of mutations in exons 5, 7, 8 of p53. A total of 26 BIBL as well as other lymphoma/leukemia samples, stained strongly by immunohistochemistry with three antibodies directed against human p53. Five of 6 BIBL samples with p53 mutations stained strongly for p53, but 20 lymphoma samples with no detectable p53 mutations also stained strongly for p53. Of note, however, 10 hyperplastic, nonmalignant lymph nodes from individuals either infected or not infected with HIV had negligible staining for p53 protein. In conclusion, p53 mutations occur in about 14% BIBL samples; the frequency of p53 mutations in BIBL in individuals with and without AIDS was similar. Positive p53 immunohistochemistry did not correlate with detectable p53 mutations in the same tissue, but positive immunohistochemical staining for p53 was only found in neoplastic lymph nodes. This latter finding provides a strong warning that p53 immunochemistry with available reagents cannot be used to determine which tumors have mutations of p53.  相似文献   
8.
Hodgkin disease: CT of the thymus   总被引:2,自引:0,他引:2  
Heron  CW; Husband  JE; Williams  MP 《Radiology》1988,167(3):647-651
The computed tomography (CT) scans in two groups of patients with Hodgkin disease were reviewed to determine the frequency of thymic enlargement. In 50 CT scans from 50 patients with evidence of thoracic disease on CT scans who were examined for primary staging, the thymus was enlarged in 15 of 50 (30%). Fifty CT scans were obtained from 44 patients at the time of 50 separate episodes of known or suspected relapse. Relapse occurred in the mediastinum in 12 episodes, lung parenchyma in five, and both sites in one. Thymic enlargement thought to be due to involvement by disease was present in seven of 18 (38%). Mediastinal disease was associated with thymic enlargement in all but one patient in whom a thymic cyst developed after radiation therapy. Differentiation of thymic enlargement from enlarged superior mediastinal lymph nodes was easily made in all but two patients. Thymic enlargement in the absence of lymph node enlargement may indicate a different disease, since isolated Hodgkin disease of the thymus is uncommon. Primary thymic tumor should be considered initially, whereas after treatment, rebound hyperplasia of the thymus may be the cause of enlargement.  相似文献   
9.
Simon  SI; Rochon  YP; Lynam  EB; Smith  CW; Anderson  DC; Sklar  LA 《Blood》1993,82(4):1097-1106
We have recently found that antibodies to L-selectin, the homing receptor on neutrophils, are as effective as those to beta 2-integrin at blocking formyl peptide-stimulated aggregation. Therefore, we investigated the requirements for expression of L-selectin and beta 2- integrin on adjacent cells during aggregation. Fluorescence flow cytometry allowed characterization of aggregates on the basis of size and color, as well as antibody binding to these two adhesive molecules. Formyl peptide-stimulated aggregate formation was measured for individual populations fluorescently labeled red (LDS-751) or green (CD44-FITC), and interpopulation red-green cell conjugates. Blocking either the beta 2-integrin or L-selectin adhesive epitope with monoclonal antibody on individual cell populations resulted in an approximately 50% reduction in two-color aggregation as compared with that in unblocked samples. Shedding the L-selectin on a cell population by preincubation with complexes of lipopolysaccharide and its plasma membrane binding protein also decreased aggregation to a control population by approximately 50%. We examined the aggregation of neutrophils from patients genetically deficient in beta 2-integrin and clinically leukocyte adhesion deficient (LAD). LAD adhesion to normal neutrophils was dependent on the expression of L-selectin on LAD cells and beta 2-integrin on normal cells. Thus, the minimum requirement for adhesion between two mixed populations of neutrophils was that one population expressed the beta 2-integrin and the other expressed the L- selectin adhesive epitope.  相似文献   
10.
The advent of whole‐exome next‐generation sequencing (WES) has been pivotal for the molecular characterization of Mendelian disease; however, the clinical applicability of WES has remained relatively unexplored. We describe our exploration of WES as a diagnostic tool in a 3½‐year old female patient with a 2‐year history of episodic muscle weakness and paroxysmal dystonia who presented following a previous extensive but unrevealing diagnostic work‐up. WES was performed on the proband and her two parents. Parental exome data was used to filter potential de novo genomic events in the proband and suspected variants were confirmed using di‐deoxy sequencing. WES revealed a de novo non‐synonymous mutation in exon 21 of the calcium channel gene CACNA1S that has been previously reported in a single patient as a rare cause of atypical hypokalemic periodic paralysis. This was unexpected, as the proband's original differential diagnosis had included hypokalemic periodic paralysis, but clinical and laboratory features were equivocal, and standard clinical molecular testing for hypokalemic periodic paralysis and related disorders was negative. This report highlights the potential diagnostic utility of WES in clinical practice, with implications for the approach to similar diagnostic dilemmas in the future.  相似文献   
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