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991.
Migot-Nabias F Deloron P Ringwald P Dubois B Mayombo J Minh TN Fievet N Millet P Luty A 《Transactions of the Royal Society of Tropical Medicine and Hygiene》2000,94(5):557-562
Two populations of schoolchildren from Gabon and Cameroon were tested in 1995 for their immunological reactivity to synthetic peptides (LSA-Rep, LSA-J and LSA-CTL) from Plasmodium falciparum liver stage antigen-1 (LSA-1). The prevalence and levels of both cellular (lymphocyte proliferation, tumour necrosis factor alpha (TNF alpha), interferon gamma (IFN gamma), and interleukin-10 (IL-10)) and humoral (immunoglobulin G) responses were determined. Protection from clinical malaria, determined after a prospective 1 year study in both sites, was associated with elevated proliferative responses to LSA-Rep and LSA-CTL in the Gabonese children, as well as with higher antibody levels to both schizont extract and LSA-Rep. The prevalence of peptide-stimulated TNF-alpha secretion was higher in the Cameroonian group, but higher levels of antibodies to LSA-Rep and LSA-J were found in the Gabonese children. The immunological differences observed between children in the 2 study sites are discussed in the context of both epidemiological and individual host factors. 相似文献
992.
Three patients demonstrated transient neonatal hypothyroidism, presumably secondary to maternally derived thyrotropin (TSH)-blocking antibodies. Although transient, this disorder might not have been benign in the first child, who exhibited significant developmental delay. A thyroid scan was not helpful in making this diagnosis. Although uncommon, this disorder should be suspected in infants with a maternal history of autoimmune thyroid disease, multiple siblings with congenital hypothyroidism, or a clinical course characterized by continually suppressed TSH levels, despite low doses of levothyroxine sodium replacement. Measurement of TSH-blocking antibodies may be used in the diagnosis of transient neonatal hypothyroidism at birth and is becoming more readily available from reference laboratories. Once diagnosed, the patient may then be prepared for monitored withdrawal of levothyroxine replacement therapy at 2 to 3 years of age and will not be committed to lifelong replacement therapy. 相似文献
993.
Modulation of prolactin responses to gonadotropin releasing hormone by acute testosterone infusions in normal women 总被引:1,自引:0,他引:1
The administration of gonadotropin releasing hormone (GnRH) has been shown to stimulate prolactin (PRL), suggesting its role as an inducer of PRL release. This study addresses whether testosterone may modulate the release of PRL with GnRH during the early follicular phase when this stimulatory effect is not usually observed. Chromatographically pure testosterone was administered intravenously to 13 women in 2 doses (100 micrograms and 1000 micrograms) over a 6-hour period. GnRH (100 micrograms) was administered as a bolus 2 hours before and 4 hours after beginning testosterone. In addition, 3 women received testosterone twice, 3 months apart, with testolactone pretreatment on the second occasion. Serum testosterone rose in all patients and achieved maximum steady-state levels by 120 minutes. Serum estradiol (E2) was increased in subjects receiving the larger dose of testosterone but was unchanged with the lower dose and with the addition of testolactone. PRL did not increase significantly after GnRH before testosterone infusion but showed a significant increase after testosterone as well as after testosterone with testolactone. This effect did not appear to be dose-related. 相似文献
994.
995.
We report a retrospective review of peptic ulcer disease (PUD) in children seen at Children's Hospital of Michigan, over 10 years (1971-1980). Of the 61 included, 31 had primary ulcers and 30 had stress ulcers. The diagnosis was made by either barium meal or endoscopy, at surgery, or at autopsy. Stress ulcers were commoner in children less than 4 years of age and were precipitated by various conditions leading to shock. The majority of these patients required surgery for perforation or bleeding. Primary ulcers were more common in children older than 4 years. The most common presenting symptoms in this group were abdominal pain and gastrointestinal bleeding. The majority of patients with primary PUD received medical therapy in the form of antacids and/or cimetidine. In one-third of these patients, surgery was necessary for complications such as intractable pain, perforation, or massive recurrent hemorrhage. 相似文献
996.
Retrobulbar haemorrhage is an uncommon but well-documented complication of retrobulbar anaesthetic blocks in ocular surgery. Peribulbar anaesthesia has been advocated to be equally effective but safer. The incidence of retrobulbar haemorrhage with peribulbar blocks is very low. We report a case in which a peribulbar anaesthetic for cataract surgery resulted in sight-threatening retrobulbar haemorrhage within the medial rectus muscle and required an anterior orbitotomy and direct decompression of the muscle. The surgery was successful. This case illustrates a potentially serious complication of peribulbar anaesthesia, with the successful outcome achieved by rapid definitive diagnosis and intervention. 相似文献
997.
Objectives. To describe the impact of prostate-specific antigen (PSA) screening on the health-related quality of life (HRQOL) and anxiety of men with a family history of prostate cancer.Methods. We asked 334 brothers or sons of men with prostate cancer who agreed to undergo PSA testing to fill out HRQOL questionnaires. The questionnaires were the RAND SF-36 (generic HRQOL) and State-Trait Anxiety Inventory (anxiety-specific). Participants completed the questionnaires at the time of screening, while waiting for the results, and after receiving normal results. Sociodemographic and HRQOL variables were entered into a logistic regression model to identify factors associated with the deterioration of HRQOL, defined as a decrease of at least one standard error of measurement. Only men with normal PSA results were considered.Results. Among 334 candidates, 273 underwent PSA measurement and 220 candidates with a PSA of 4 ng/mL or less returned completed questionnaires. Of these, in 20% their anxiety moderately deteriorated and in 20% their HRQOL minimally deteriorated during the screening process. Factors associated with HRQOL deterioration included age between 50 and 60 years, having more than two relatives with prostate cancer, an anxious personality, a high level of education, and having no children presently living at home.Conclusions. Screening with normal PSA results is accompanied by a minimally to moderate deterioration of HRQOL in some subjects. The identification of such individuals before screening provides opportunities to improve their HRQOL during the screening process. 相似文献
998.
Chondrosarcoma of the larynx: a clinicopathologic study of 111 cases with a review of the literature
Chondrosarcomas of the larynx are rare tumors accounting for about 0.5% of all laryngeal primary tumors. A total of 111 laryngeal chondrosarcoma cases, diagnosed between 1970 and 1997, were retrieved from the Otorhinolaryngic-Head & Neck Tumor Registry of the Armed Forces Institute of Pathology. There was a 3.6:1 male/female ratio of patients 25-91 years of age (mean, 64.4 years). Patients presented most frequently with hoarseness (n = 72 patients) present for a mean of 28.2 months. The majority of tumors involved the cricoid cartilage (n = 77) with a mean size of 3.5 cm. All tumors were invasive and malignant by radiology and/or histology (into bone within the ossified laryngeal cartilages in 52 tumors). Most tumors were low-grade lesions: grade 1 (n = 51), grade 2 (n = 54); there were six grade 3 tumors. An associated benign chondroma with (n = 41 tumors) or without ischemia (n = 24 tumors) was noted. All patients had surgery and five had radiation therapy. Wide excision or voice-sparing surgery was used in 73 patients, whereas 37 patients had a laryngectomy. Recurrences occurred in 20 (18%) patients, 10 of whom underwent salvage laryngectomy. At the last follow-up, 102 patients had no evidence of disease (alive or dead, mean 11.2 years) and five patients had evidence of disease (alive, one patient, 6.5 years; dead, four patients, mean 6.4 years). The six patients with high-grade chondrosarcoma were all without disease at the last follow-up (mean, 15.1 years). There was no difference in clinical outcome based on grade (p = 0.210), location (p = 0.078), or treatment (p = 0.607) but was worse for patients with a myxoid-type chondrosarcoma (p = 0.044). Primary laryngeal chondrosarcomas are typically low- to moderate-grade lesions involving the cricoid cartilage, frequently associated with a chondroma. They usually portend an excellent overall long-term prognosis with initial conservative voice-sparing surgery. 相似文献
999.
1000.
Sapp H Ithamukkala S Brien TP Ayata G Shaz B Dorfman DM Wang HH Antonioli DA Farraye FA Odze RD 《The American journal of surgical pathology》2002,26(11):1484-1492
Lymphocytic colitis (LC) and collagenous colitis (CC) are diseases characterized by the presence of marked intraepithelial lymphocytosis. Both of these disorders affect primarily the colon. However, involvement of the distal small intestine has not been systematically studied. The purpose of this study was to evaluate the type and degree of intraepithelial lymphocytosis in the terminal ileum of patients with LC or CC. Terminal ileal mucosal biopsies from 22 patients with LC (male/female ratio 0.22, mean age 47 years) and 23 with CC (male/female ratio 0.43, mean age 54 years) were evaluated for the number of intraepithelial lymphocytes (IEL) per 100 epithelial cells (EC) both in the villi and crypts. The results were compared with 30 patients with inflammatory bowel disease (16 with Crohn's disease [CD], 14 with ulcerative colitis [UC]) and 24 patients (male/female ratio 0.33, mean age 44 years) without colonic pathology as normal controls. None of the patients had celiac sprue. Paired terminal ileum and colonic mucosal biopsies from 6 patients with LC, 4 with CC, 5 with CD, 5 with UC, and 10 normal controls were also immunohistochemically stained with monoclonal antibodies to CD3, CD8, CD20, and a class II MHC antigen (LN3-HLA-DR). In the villi the IEL count/100 EC was 11.8 +/- 1.8 in LC and 10.3 +/- 1.9 in CC (p = 0.3). These values were both significantly higher than in CD (2.8 +/- 0.4, p <0.001), UC (3.1 +/- 0.4, p <0.001), or normal controls (2.2 +/- 0.2, p <0.001). In the crypts the IEL count was 3.8 +/- 0.5 in LC and 3.2 +/- 0.5 in CC (p = 0.3). These values were also significantly higher than in CD (2.3 +/- 0.4, p = 0.02), UC (2.1 +/- 0.3, p = 0.02), or normal controls (1.5 +/- 0.2, p <0.001). The presence of >5 IELs/100 EC in terminal ileum biopsies was highly specific for LC and CC (specificity 98%, sensitivity 73% and 56% for LC and CC, respectively). The IEL phenotype was similar in all groups of patients and in the ileum and colon of individual patients. Intraepithelial lymphocytes were CD3+, CD8+, CD20-, and LN3-HLA-DR-, indicative of a suppressor T-cell phenotype. Intraepithelial lymphocytosis occurs in the terminal ileum in patients with LC or CC and may be helpful in diagnosing these conditions and distinguishing LC or CC from CD or UC in diagnostically difficult cases. The results suggest that the terminal ileum may be involved by a similar pathogenic process as the colon in LC and CC. 相似文献