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91.
A case of sparsely granulated growth hormone cell adenoma associated with lymphocytic hypophysitis. 总被引:1,自引:0,他引:1
Lymphocytic hypophysitis is in itself rare and usually occurs in the postpartum period or the last trimester of pregnancy. It has not been described in combination with a pituitary tumor. A twenty-two year old woman, who had never been pregnant, presented with a history of nine months amenorrhea and spontaneous galactorrhea. She was not taking any medication and had never used oral contraceptives. Physical examination was unremarkable except that whitish fluid could be expressed from both breasts. Her visual fields were normal. Her serum PRL levels was high at 105.7 micrograms/l and increased to 138.4 micrograms/l at 60 minutes in a triple bolus test. GH values were normal and there was no evidence of overproduction of other pituitary hormones. CT scan showed an intrasellar mass with suprasellar extension. A tumor was selectively removed transsphenoidally. Morphologic examination revealed a clinically silent sparsely granulated growth hormone cell adenoma with lymphocytic infiltration of the adjacent pituitary tissue. Postoperatively her menstrual periods resumed and she conceived despite a slightly elevated PRL level. Three months after an uneventful pregnancy and full term delivery her PRL level was 69.9 micrograms/l and increased to 102.2 micrograms/l at 60 min. Basal GH and cortisol levels were normal. She remains well without replacement fourteen months after delivery. This case is of interest because it is the first reported simultaneous occurrence of a pituitary adenoma and lymphocytic hypophysitis and also because the hypophysitis preceded her first pregnancy. 相似文献
92.
Platelet-melanoma cell interaction is mediated by the glycoprotein IIb- IIIa complex 总被引:3,自引:0,他引:3
A human malignant melanoma cell line (M3Dau) was observed by electron microscopy to interact directly with human platelets and induced platelet aggregation. Fab fragments of a monoclonal antibody MoAb (LYP18), directed against the platelet glycoprotein (GP) IIb-IIIa complex, inhibited platelet-melanoma interactions and platelet-platelet aggregation. M3Dau melanoma cells bind LYP 18 and synthesize IIb-IIIa- like GPs. When the melanoma cells were preincubated with LYP 18, tumor- platelet interaction did not occur, suggesting that the interaction may be mediated by the IIb-IIIa-like GPs present on the melanoma cell surface. Glanzmann's thrombasthenic platelets, lacking GPIIb and IIIa, did not interact with melanoma cells, indicating that the platelet GPIIb-IIIa complex is also necessary for the platelet-melanoma cell interaction. This work demonstrates the importance of the IIb-IIIa-like GPs, present on M3Dau melanoma cells, in mediating tumor-platelet interactions. 相似文献
93.
Metabolic activity of phagocytosing granulocytes in chronic granulocytic leukemia: ultrastructural observation of a degranulation defect 总被引:4,自引:0,他引:4
Cramer E; Auclair C; Hakim J; Feliu E; Boucherot J; Troube H; Bernard JF; Bergogne E; Boivin P 《Blood》1977,50(1):93-106
The functional capacities of granulocytes in patients with chronic granulocytic leukemia are still a subject of controversy, probably due to the heterogeneity of the abnormalities observed from patient to patient. For a better definition of these abnormalities, 14 patients with untreated chronic granulocytic leukemia were studied. The patients were divided into three groups on the basis of the functional activities of their phagocytosing granulocytes. In four patients (group I), the granulocytes were normal in respect to particle ingestion, nitroblue tetrazolium (NBT)-stimulated reduction, cyanide-insensitive oxygen (O2) consumption, superoxide anion (O2-)-stimulated production, hydrogen peroxide (H2O2) production, and iodination. They also had a normal myeloperoxidase (MPO) content. In four patients (group III), the granulocytes were significantly defective in all of these activities. In the six remaining patients (group II), all the initial metabolic steps of the phagocytosing granulocytes (ingestion, NBT reduction, O2 consumption, O2-production, H2O2 production) were normal, as were the MPO content of the granulocytes, while iodination was strikingly decreased. These metabolic features suggested a degranulation defect which was observed ultrastructurally in the only patient studied among these six. The phagocytosing granulocytes of this patient did not degranulate and no deposits of MPO activity were seen in the phagosomes. 相似文献
94.
Betty Liu Rory K. J. Murphy Deanna Mercer Lawrence Tychsen Matthew D. Smyth 《Child's nervous system》2014,30(7):1197-1200
Purpose
Diagnosing idiopathic intracranial hypertension (IIH), or pseudotumor cerebri, can be challenging in children. Diagnosis is based on lumbar puncture, opening pressures, and appearance of the optic disk. Misdiagnosis of papilledema, a typical finding, may lead to unnecessary treatments and procedures. We report 52 children over a 6-year period to better identify the true incidence of pseudopapilledema and other factors that may confound the diagnosis of IIH.Methods
A retrospective chart review approved by the Institutional Review Board was performed. Fifty-two children under the age of 21 referred to us based on suspected IIH or papilledema from 2007 to 2013 are included in this study. Patients were assessed by a pediatric ophthalmologist and a neurosurgeon.Results
Fifty-two children were initially diagnosed with IIH and/or papilledema; 26 diagnoses were revised to pseudopapilledema after pediatric ophthalmological review. Out of those 26 patients with pseudopapilledema, 14 had undergone lumbar punctures, 19 had MRIs, 9 had CTs, and 12 were taking medications—these medications were discontinued upon revision of the diagnoses. The difference in the CSF opening pressure between children diagnosed with true IIH (32.7 cm H2O) and children diagnosed with pseudopapilledema (24.7 cm H2O) was statistically significant.Conclusions
IIH diagnosis is heavily reliant on the appearance of the optic disk. Pediatric ophthalmological assessment is essential to carefully examine the optic disk and prevent further unnecessary investigation and treatments. Close communication between pediatricians, ophthalmologists, and neurosurgeons can avoid invasive procedures for children who do have pseudopapilledema, and not IIH or associated papilledema. 相似文献95.
Louise C. McLoughlin Niall F. Davis Catherine M. Dowling Richard E. Power Ponusamy Mohan David P. Hickey Gordon P. Smyth Molly M.P. Eng Dilly M. Little 《Clinical transplantation》2014,28(3):307-313
Renal transplantation in recipients with an ileal conduit is uncommon and occasionally controversial as it has been associated with high morbidity and mortality rates. We report on 17 patients with an ileal conduit who received a deceased donor renal transplant at our institution between January 1986 and December 2012. We retrospectively reviewed their allograft and surgical outcome. There were four mortalities at five, five, 39, and 66 months post‐transplant. Sixteen of 17 grafts functioned immediately; one patient had primary non‐function secondary to vascular thrombosis. Thirteen of 17 (76.5%) grafts were functioning at a mean follow‐up period of 105 months. The mean serum creatinine at follow‐up was 111 μM (±38.62). Five patients had seven episodes of urosepsis requiring hospital admission, and five patients received treatment for renal stone disease. We conclude that given improvements in immunosuppression, surgical technique, infection treatment, and selection criteria, we believe that renal transplantation in the patient with an ileal conduit yields excellent graft survival, although there is a high morbidity rate in this cohort of patients in the long term. 相似文献
96.
A 73‐year‐old man presented with a 6‐month history of exertional headaches. Exercise tolerance test demonstrated progressive ischaemic changes concomitant with worsening headache. Cardiac cephalgia was diagnosed and his symptoms resolved after coronary artery bypass surgery. Cardiac cephalgia may occasionally present as exertional headache without chest symptoms. 相似文献
97.
Genome sequence determinations and analyses of novel circoviruses from goose and pigeon 总被引:12,自引:0,他引:12
The genomes of novel circoviruses from goose and pigeon, which were isolated using degenerate primer and inverse primer PCR methods, were cloned and sequenced. Comparative nucleotide (nt) sequence analyses showed that the goose circovirus (GCV) and pigeon circovirus (PiCV) possessed genomes which were 1821 and 2037 or 2036 nt, respectively, and which had features in common with the genomes of porcine circoviruses types 1 and 2 (PCV1, PCV2) and psittacine beak and feather disease virus (BFDV), such that they can now be assigned to the genus Circovirus of the family Circoviridae. Common features include the possession of (i) a potential stem-loop/nonanucleotide motif with which the initiation of rolling circle replication of the virus DNA is associated; (ii) two major ORFs, located on the virus (V1 ORF) and complementary (C1 ORF) strands, which encode the replication-associated protein (Rep) and capsid protein, respectively; (iii) high levels of amino acid identity (41.2--58.2%) shared with other circovirus Rep proteins; and (iv) direct/inverted repeat sequences within the putative intergenic region. On the basis of nt and amino acid sequence identities, GCV is substantially less closely related to BFDV than PiCV is to BFDV. 相似文献
98.
Naiara G. Bediaga Alexandra L. Garnham Gaetano Naselli Esther Bandala-Sanchez Natalie L. Stone Joanna Cobb Jessica E. Harbison John M. Wentworth Annette-G. Ziegler Jennifer J. Couper Gordon K. Smyth Leonard C. Harrison 《Diabetes》2022,71(3):566
Type 1 diabetes in children is heralded by a preclinical phase defined by circulating autoantibodies to pancreatic islet antigens. How islet autoimmunity is initiated and then progresses to clinical diabetes remains poorly understood. Only one study has reported gene expression in specific immune cells of children at risk associated with progression to islet autoimmunity. We analyzed gene expression with RNA sequencing in CD4+ and CD8+ T cells, natural killer (NK) cells, and B cells, and chromatin accessibility by assay for transposase-accessible chromatin sequencing (ATAC-seq) in CD4+ T cells, in five genetically at risk children with islet autoantibodies who progressed to diabetes over a median of 3 years (“progressors”) compared with five children matched for sex, age, and HLA-DR who had not progressed (“nonprogressors”). In progressors, differentially expressed genes (DEGs) were largely confined to CD4+ T cells and enriched for cytotoxicity-related genes/pathways. Several top-ranked DEGs were validated in a semi-independent cohort of 13 progressors and 11 nonprogressors. Flow cytometry confirmed that progression was associated with expansion of CD4+ cells with a cytotoxic phenotype. By ATAC-seq, progression was associated with reconfiguration of regulatory chromatin regions in CD4+ cells, some linked to differentially expressed cytotoxicity-related genes. Our findings suggest that cytotoxic CD4+ T cells play a role in promoting progression to type 1 diabetes. 相似文献
99.
100.
Analysis of eight groups of data collected at varying intervals during a period of seven years showed fluctuations in the sensitivity of tests to diagnose trichomoniasis in women. The best results were obtained from fresh, correctly prepared Diamond's medium, Feinberg-Whittington's medium, and modified Squires and McFadzean's medium (which showed 82% to 94% relative sensitivity). Poor results were identified consistently in commercially prepared Bushby medium from one source (40% relative sensitivity) and in a batch of commercially prepared Squires and McFadzean's medium from which chloramphenicol had been omitted (23% relative sensitivity). Examination of wet film, culture, and exfoliative cytology stained by Papanicolaou's method were shown to be indispensable for auditing the performance of each test and to maintain the quality of a diagnostic service. 相似文献