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991.
DNA flow cytometry was performed on fine needle aspirates from the testes of 40 oligozoospermic or azoospermic men under investigation for infertility. The DNA distributions from men with increased FSH serum levels were all abnormal. The values were below the level of detection (or very low) with respect to both haploid (1c) and tetraploid (4c) cells, indicating reduced proportions of spermatids and primary spermatocytes. This confirms that increased FSH serum levels are indicative of severely damaged spermatogone-sis. The findings of both normal and abnormal testicular DNA distributions in the large group of oligozoospermic men indicate that the presented method may be of importance for evaluating prognosis, and for selection of men for further investigation and therapy. Many azoospermic men showed normal testicular DNA distribution patterns, suggesting the value of DNA flow cytometry for selection of such cases for surgical treatment (epididymovasos-tomia). 相似文献
992.
Longitudinal melanonychia with spreading pigmentation in Laugier-Hunziker syndrome: a report of two cases 总被引:2,自引:0,他引:2
We present two cases of Laugier-Hunziker syndrome with longitudinal melanonychia and Hutchinson's sign, associated with essential melanotic pigmentation of the mouth and lips. 相似文献
993.
A case-control study on the correlation between levels of polychlorinated biphenyls (PCB) and p,p′ -DDE in adipose tissue of deceased cancer and noncancer patients is reported and related to potential confounders such as weight, height, occupation, and residence of deceased individuals, etc. Although taking into account the above-mentioned confounders, a significant association remained between the concentrations of PCB and DDE in the subcutaneous adipose fat and cancer. 相似文献
994.
Diagnosis of oligospermiogenesis was made in 76 infertile subjects submitted to testicular biopsy. Histological examinations demonstrated a reduction in mature spermatids (Sc. Sd.-Clermont classification) in the tubular sections. Comparison of histological data with findings from seminal fluid analyses in these subjects revealed: a) a pathological seminal fluid pattern in all cases of oligospermiogenesis, b) these patients may show either an azoospermic or oligozoospermic seminal fluid pattern; statistical analyses confirmed an almost equal distribution of the two conditions.
Bei 76 andrologischen Patienten wurden die Diagnose einer Oligospermatogenesis mittels der Hodenbiopsie gestellt. Die histologische Untersuchung ergab eine Reduzierung der reifen Spermatiden in den Tubuli seminiferi. Ein Vergleich der histologischen Befunde mit den Ergebnissen der Samenanalysen dieser Patienten zeigte bei allen Fällen von Oligospermatogenesis pathologische! permawerte und gleichfalls entweder eine Azoospermie oder eine Oligozoospermie im Sperma; die statistische Analyse ergab eine gleichmäßige Verteilung dieser beiden Voraussetzungen. 相似文献
Zusammenfassung
Bei 76 andrologischen Patienten wurden die Diagnose einer Oligospermatogenesis mittels der Hodenbiopsie gestellt. Die histologische Untersuchung ergab eine Reduzierung der reifen Spermatiden in den Tubuli seminiferi. Ein Vergleich der histologischen Befunde mit den Ergebnissen der Samenanalysen dieser Patienten zeigte bei allen Fällen von Oligospermatogenesis pathologische! permawerte und gleichfalls entweder eine Azoospermie oder eine Oligozoospermie im Sperma; die statistische Analyse ergab eine gleichmäßige Verteilung dieser beiden Voraussetzungen. 相似文献
995.
In a prospective analysis of the diagnostic value of immunophenotyping in acute leukemias (ALs), all patients admitted to a pediatric and a haematological department suspected of AL were examined consecutively with a selected panel of monoclonal antibodies (Mabs) against leucocyte differentiation antigens during an 8-month period. A total of 189 samples obtained from blood, bone marrow, spinal fluid and lymph nodes in 120 cases were all analysed blindly. The results were correlated with a routine morphological/cytochemical evaluation. Differing results were obtained in seven out of 38 cases in which the immunologically defined diagnosis was acute myeloid leukemia (AML), and in one out of 21 cases with the primary diagnosis acute lymphoid leukemia (ALL). Immunological phenotyping disclosed two cases of hybrid leukemia, one case of biphenotypic and one case of bilineal leukemia. No evidence of malignancy was found in 36 cases, 30 cases of blood and bone marrow and six cases of spinal fluids, in every case in accordance with the pathological examination. These results demonstrate that a first-line immunological evaluation of bone marrow, blood and spinal fluid from patients suspected of AL is highly capable of discriminating between different malignant and nonmalignant haematological diseases and also between various types of leukemias. The immunological methods do, however, require a sufficient amount of material which was a limiting factor in 14 out of 120 examinations, mainly from patients treated with several cycles of cytostatics. It is concluded that immunophenotyping can be used as a first-line diagnostic tool in malignant haematological diseases. 相似文献
996.
The Marfan syndrome is a genetic disorder of connective tissues resulting in ocular, cardiovascular, and musculoskeletal deformities. The authors reviewed 22 cases of Marfan syndrome. Forty-five percent (ten of 22) of the patients had acetabular protrusion, with one-half of these being unilateral and one-half bilateral. Scoliosis was associated with acetabular protrusion in 90% of cases (nine of ten). The authors conclude that acetabular protrusion is a common skeletal finding in the Marfan syndrome. 相似文献
997.
Inverse Monte Carlo (IMOC) is a unified reconstruction algorithm for single photon emission computed tomography (SPECT) that provides simultaneous compensation for attenuation and collimator divergence. IMOC was applied to the reconstruction of SPECT images of a brain phantom with iodine-123 and high-resolution collimation. Projection sets containing 80,000, 540,000, and 5.2 million counts were reconstructed. Comparison with filtered back-projection reconstructions showed that the IMOC reconstructions provided superior noise and resolution characteristics at all three photon densities. Results of this study indicate that IMOC may allow the use of high-resolution, low-sensitivity collimation for SPECT studies, which have traditionally provided photon yields too low for useful imaging. 相似文献
998.
Two hundred ninety patients with Hodgkin's disease pathologic stage (PS) I or II were treated in the prospective randomized trial of the Danish National Hodgkin Study (see Appendix) with radiotherapy +/- adjuvant combination chemotherapy. The initial tumor burden of each patient was assessed, combining tumor size of each involved region and number of regions involved. Multivariate analyses of prognostic factors including treatment, tumor burden, histologic subtype, pathologic stage, number of involved regions, mediastinal size, systemic symptoms, erythrocyte sedimentation rate (ESR), sex, and age were carried out. With regard to disease-free survival tumor burden was by far the most important prognostic factor for patients treated with adjuvant chemotherapy as well as for patients treated with radiotherapy alone. With regard to survival from Hodgkin's disease only tumor burden and age were independently significant. A combination of tumor burden, histologic subtype, and sex singled out patients with a high relapse rate both after radiotherapy only, and after radiotherapy plus chemotherapy. This combination also singled out patients destined to die from Hodgkin's disease more accurately than other prognostic factors. 相似文献
999.
T F Orntoft H Wolf H Clausen E Dabelsteen S Hakomori 《International journal of cancer. Journal international du cancer》1989,43(5):774-780
A complete panel of mouse monoclonal antibodies (MAbs) against Type-2 chain (GaI beta I-4GlcNAc-R) blood-group antigens (N-acetyl-lactosamine, Lex, H, Ley, A monofucosylated, Aley, repetitive A) was used in a detailed immunohistological study of the modulation of these carbohydrate antigens in transitional-cell carcinomas. The histological and cellular locations of these antigens were studied in 19 normal bladder biopsies and 53 transitional-cell carcinomas with as well as without neuraminidase treatment of tissue sections in order to uncover potential sialylated antigens. The antigen expression was correlated to individual A1A2BO, Lewis, and secretor status. Several alterations of blood group expression were found: (1) loss of A and H antigens with accumulation of Ley antigens; (2) loss of correlation between antigen expression and secretor status; (3) disruption of the orderly stratification of blood-group antigen expression in relation to cell layers; and (4) changes in subcellular location of antigen expression. The present data indicate that deletion of Type-2 chain ABH antigens in transitional-cell carcinomas is associated with alpha 1-3 fucosylation of the H antigen leading to accumulation of Ley antigens. 相似文献
1000.
Do endogenous retroviruses have etiological implications in inflammatory and degenerative nervous system diseases? 总被引:1,自引:0,他引:1
Vertebrates carry large numbers of endogenous retroviruses (ERVs) and related sequences in their genomes. These retroviral elements are inherited as Mendelian traits. Generally, ERVs are defective without the ability of being expressed as viral particles. However, ERV sequences often have a potential for expression of at least some proteins. So far, the possible biological significance of ERVs is not clear. Nonetheless, there are observations suggesting a connection between ERVs and various diseases. This is the case with murine lupus and a spinal cord disease of certain mouse strains. In the present review, we discuss possible mechanisms by which ERVs could contribute to the development of human degenerative and inflammatory nervous system diseases, including direct effects on nervous system cells and immune cells. Interactions between ERVs and infectious viruses are also discussed. Finally, we review a possible retroviral etiology of multiple sclerosis. 相似文献