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991.
Norethisterone enanthate (NET-En), an established intramuscular long-acting contraceptive agent, has previously been shown to be effective in inhibiting fertility in two rodent species even 4 days after oral ingestion. Pharmacokinetics of NET and NET-En were studied after oral and intramuscular doses in two animal species and a few women. The results suggest that the NET-En was absorbed within a day in all the species after oral dose. The estimates of relative bioavailability ranged from 13 to 51% in rabbits, monkeys, and women. The elimination half-life was 5–10 days. The presence of the active component, NET, in the circulation over the experimental period of 15 days suggests that NET-En could be useful as a long-acting oral pill. The suppression of progesterone levels during the luteal phase of menstrual cycle in women also supports this finding.  相似文献   
992.
Aims : Adenocarcinomas account for about 60% of metastatic cancers of unknown primary (CUP) site. In such a clinical CUP situation, histopathologists are challenged to differentiate renal cell carcinomas (RCC) from other adenocarcinomas with similar immunophenotypes, especially chemotherapeutically treatable mammary and ovarian carcinomas. Methods and results : Recently, we produced a monoclonal antibody (mAb), designated 138H11, against human gamma-glutamyltransferase (γGT), which stained over 98% primary clear cell and chromophilic RCC on frozen sections. The 138H11 epitope could not be stained using conventional techniques in most paraffin-embedded sections of the same origin, due to destruction by formalin fixation below the detection level. Here, we demonstrate that mAb 138H11 can specifically stain γGT in paraffin-embedded primary and metastatic RCC after enhancement with an ultrasensitive immunohistochemical method. We analysed a selected subgroup of adenocarcinomas with immunophenotypes which would not allow a differentiation from RCC in a CUP situation. We found a predominantly membranous expression of the 138H11 target antigen in 26/51 primary RCC and 15/34 metastatic RCC. In contrast, all 43/43 primary ovarian and bronchial carcinomas as well as 54/54 metastases of ovarian, mammary, bronchial and gastric carcinomas were negative for mAb 138H11. Conclusions : The data suggest that mAb 138H11 is useful for the immunohistochemical differentiation of RCC from other metastatic adenocarcinomas if the primary site of the tumour is not known.  相似文献   
993.
994.
The synaptonemal complex (SC) is involved in the pairing of chromosomes during meiosis. We found that antibodies raised against a protein component (P1) of the mouse synaptonemal complex, mouse SCP1, also identified the SC in human primary spermatocytes. Biopsies from 18 men presented with infertility were evaluated by light-field microscopy and grouped into five categories: normal spermatogenesis, Sertoli cell-only syndrome, meiotic disturbances, spermiogenic (i.e. differentiation) disturbances, and other combined disturbances. In all the normal subjects the SCP1 antibody distinctly stained the synaptonemal complexes of primary spermatocytes, whereas Sertoli cells, spermatogonia or spermatids were never stained. In three of the groups, which had germ cells but showed spermatogenic disturbances, the staining was similar to that seen in normal subjects. In sharp contrast to this, in sections from men with Sertoli cell-only syndrome no specific staining was seen. This study demonstrates that a SCP1-related protein is also conserved in the synaptonemal complex in meiotic cells from man. Further studies will reveal to what extent the absence or the non-functionality of SCP1 contributes to male infertility.   相似文献   
995.
 Soft tissue tumours represent a heterogeneous group of mesenchymal lesions, and their classification is the subject of continuous debate. Chromosome analysis, molecular cytogenetics and molecular assays may become increasingly useful in diagnosis, and this review summarises advances in the cytogenetic characterisation and classification of soft tissue tumours. Among the group of fibrous lesions, superficial fibromatosis exhibits trisomy 8. This genomic change is also observed in desmoid fibromatosis in association with trisomy 20. Trisomy 11 is the most frequently observed chromosomal aberration in congenital fibrosarcoma. Dermatofibrosarcoma protuberans and giant cell fibroblastoma share a translocation t(17;22), which supports the concept of the existence of a common differentiation pathway. Adipose tissue tumours is the group in which integration of genetics and pathology has been most fruitful. Ordinary lipomas cytogenetically show an abnormal karyotype in about half the cases. Genomic changes of the 11q13 region are observed in hibernoma. Lipoblastoma exhibits a specific 8q rearrangement in 8q11-q13. Loss of material from the region 16q13-qter and 13q deletions are observed in spindle cell/pleomorphic lipomas. The well-differentiated liposarcoma/atypical lipoma group is characterised karyotypically by the presence of one extra ring and/or extra giant chromosome marker. Myxoid and round cell liposarcoma share the same characteristic chromosome change: t(12;16)(q13;p11) in most cases. In the group of smooth muscle lesions most data are derived from uterine leiomyomas, which can be subclassified cytogenetically into seven different types. Half of all leiomyomas are chromosomally normal; the other half have one of six possible consistent chromosome changes. Alveolar rhabdomyosarcoma is characterised cytogenetically by two variant translocations t(2;13)(q35;q14) and t(1;13)(p36;q14). Among tenosynovial tumours, the localised type of giant cell tumour of tendon sheath exhibits two different karyotypic changes. One involves 1p11 in a translocation with chromosome 2 or with another chromosome. A second type involves 16q24. Synovial sarcoma is characterised cytogenetically by a translocation occurring between chromosome 18 and presumably two adjacent loci on the X chromosome. In neural tumours, abnormalities of chromosome 22 have been reported in benign schwannomas and perineuriomas. Malignant peripheral nerve sheath tumours exist in two main forms: sporadic and associated with the NF-1 syndrome. Karyotypes are very complex, but chromosomes 17q and 22q are very often involved. Clear cell sarcoma is characterised cytogenetically and molecularly by a translocation t(12;22)(q13;q12). The Ewing’s sarcoma/peripheral neuroectodermal tumour category shows a central karyotypic anomaly represented by the translocation t(11;22). The two variants t(21;22) and t(7;22) are found in some cases. Among cartilaginous lesion, the most frequently described anomaly is the t(9;22)(q22;q12) in extraskeletal myxoid chondrosarcoma. Intra-abdominal desmoplastic small round cell tumour is characterised by a t(11;22)(p13;q12). Received: 5 February 1997 / Accepted: 24 February 1997  相似文献   
996.
997.
We describe a novel human zinc finger cNDA, C2H2-171. This cDNA represents an mRNA which encodes a protein of 484 amino acids and a calculated molecular weight of 54 kD. Four zinc finger-like domains are found in the C-terminal end of the protein. At the N-terminus, C2H2-171 contains a POZ/tramtrack-like domain similar to that found in the tumor associated zinc finger proteins LAZ-3/BCL-6 and PLZ-F, as well as in non-zinc finger proteins. C2H2-171 RNA is preferentially expressed in the brain, and increases during the course of murine development, with maximal expression in the adult. C2H2-171 RNA is differentially expressed in brain regions, with the highest level of expression in the cerebellum. C2H2-171 RNA was expressed at high levels in primary cerebellar granule cell neurons compared to astrocytes. The gene encoding C2H2-171 is highly conserved in vertebrates, and maps to the terminus of human chromosome 1 (1q44-ter). This chromosomal location is associated with a number of cytogenetic aberrations including those involving brain developmental anomalies and tumorigenesis. These data suggest that C2H2-171 may play an important role in vertebrate brain development and function.  相似文献   
998.
999.
Opening the doors of perception in the irritable bowel syndrome   总被引:3,自引:1,他引:2       下载免费PDF全文
L. HOUGHTON  P WHORWELL 《Gut》1997,41(4):567-568
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1000.
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