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81.
PCR analysis of the Y chromosome long arm in azoospermic patients: evidence for a second locus required for spermatogenesis 总被引:20,自引:2,他引:20
Kobayashi Kazuhiro; Mlzuno Kunihiko; Hida Akiko; Komakl Rie; Tomita Keiko; Matsushita Ikumi; Namlki Mikio; Iwamoto Teruaki; Tamura Shohzoh; Minowada Shlgeru; Nakahori Yutaka 《Human molecular genetics》1994,3(11):1965-1967
We analyzed DNA from 63 Japanese men with either azoospermiaor severe oligospermia whose Y chromosomes were cytogeneticallynormal. A total of 16 loci were examined: 15 loci on the longarm between DYS7E and DYZ1, and the YRRM1 locus, a candidategene for the azoospermic factor, AZF. One patient with a perlcentricinversion of the Y chromosome was also included. We detectedmicro-deletions in ten individuals. The YRRM1 gene was Involvedin only three of them. The remaining seven patients showed deletionbetween DYS7C and DYS239 in common, indicating the presenceof at least one additional gene, deletion of which causes azoospermia. 相似文献
82.
Junya Yoneda Ikuo Saiki Hideji Fujii Fuminori Abe Yutaka Kojima Ichiro Azuma 《Clinical & experimental metastasis》1992,10(1):49-59
We have investigated the effect of the immunomodulator ubenimex (hereafter referred to as bestatin) on the enzymatic degradation
of the extracellular matrix by human renal cell carcinoma SN12M cells during the invasive process. The invasion of SN12M cells
into reconstituted basement membrane (Matrigel) was inhibited by the presence of bestatin in a concentration-dependent manner.
However, bestatin did not have any effect on tumor cell adhesion and migration to the extracellular matrices which may be
involved in tumor cell invasion. Bestatin inhibited the degradation of type IV collagen by tumor cells, but not by tumor-conditioned
medium (TCM), in a concentration-dependent manner. We also found that bestatin inhibited hydrolysing activities towards substrates
of aminopeptidases in SN12M cells. Since bestatin was found to inhibit aminopeptidase activity, the inhibition of tumor invasion
by bestatin is likely to be associated with its action as an enzyme inhibitor. Bestatin only slightly inhibited tumor cell
plasmin activity, which can lead to the conversion of the latent collagenase to the active form, but this slight effect was
not significant. The zymography of TCM from SN12M cells showed that the treatment of tumor cells with bestatin resulted in
the disappearance of the 68 kDa type IV collagenase-enzyme level (active form) and slight reduction of the 72 kDa type IV
collagenase-enzyme level (latent form). These results indicated that bestatin may inhibit tumor cell invasion through a mechanism
involving its inhibitory action on aminopeptidases in tumor cells, suggesting that the aminopeptidase may partly be associated
with the conversion of a latent form of type IV procollagenase to an active form or the secretion of the collagenases from
tumor cells. 相似文献
83.
Hidekazu Shigematsu Yutaka Kobayashi Sumio Tateno Yoshiyuki Hiki Sadahito Kuwao 《Pathology international》1992,42(2):91-98
The correlation between glomerular immune deposition and histological alteration was studied in serial paraffin sections of kidney biopsy specimens from patients with IgA nephritis using the peroxidase antiperoxidase (PAP) method. IgA deposition was detected in preserved glomerular extracellular matrix or in newly formed interposed matrix along the capillary loops (mesangial interposition). On the other hand, deposition of IgA was scanty or absent in the distorted extracellular matrix where severe exudative inflammation or extracapillary escape of exudates was occurring segmentally. Ultrastructurally such extracellular matricial destruction was expressed as splitting or thinning of the lamina densa, as well as mesangial edema, reticulation or mesangiolysis of the axial matrix. Therefore it appears that at least two types of change in the extracellular matrix are induced by IgA immune complexes in IgA nephritis; immunogenic deposition and destruction. 相似文献
84.
Kono Y Horie M Takano M Otani H Xie LH Akao M Tsuji K Sasayama S 《Pflügers Archiv : European journal of physiology》2000,440(5):692-698
Functional ATP-sensitive K (KATP) channels have an octameric subunit structure with four pore-forming subunits (Kir6.x) and four sulfonylurea receptors (SURx). In the present study, the properties of the heteromeric KATP channel whose pore subunits are composed of Kir6.1 and Kir6.2 were examined using a heterologous expression system. In COS7 cells co-transfected with Kir6.1, Kir6.2 and SUR2A at a ratio of 1:1:2, KATP channels showed various unitary conductances between those of Kir6.1/SUR2A (33.6+/-4.2 pS) and Kir6.2/ SUR2A (67.1+/-1.6 pS). Kir6.1-6.2 tandem protein, constructed by fusing the C-terminus of Kir6.1 to the N-terminus of Kir6.2 with a ten glutamine linker sequence, also formed a channel with an intermediate conductance (58.9+/-1.5 pS). Kir6.2 and Kir6.1-6.2 showed similar sensitivity to ATP4-: half-maximal inhibition (IC50) was obtained at 14.1+/-12.8 microM and 17.6+/-9.6 microM, respectively. In the presence of Mg2+, Kir6. 1-6.2 was significantly less sensitive than Kir6.2 to MgATP (IC50=95.5+/-49.6 microM versus 18.9+/-5.0 microM). These results suggest that Kir6.1 and Kir6.2 are endowed with the potential to form a heteromeric KATP channel, which has a low sensitivity to MgATP. 相似文献
85.
A case Is presented of intermediate lymphocytic lymphoma seen In a 53 year old mate, which extensively Infiltrated systemic organs, Including the entire digestive tract from the esophagus to the rectum. Payer's patch Invasion was evident. Multiple Intestinal perforations caused death 5 months later. Surface marker studies suggested the marginal zone origin for this CD2CT B cell malignancy. 相似文献
86.
Yoshinori Marunaka Yutaka Shintani Eizo Sugimoto Naomi Niisato 《Pflügers Archiv : European journal of physiology》1996,432(3):571-573
The aim of the present study was to investigate the roles of tyrosine kinase (TK) in the insulin action on cell volume in fetal rat (20-day gestational age) type II pneumocyte. Insulin (100 nmol/l) increased cell volume, and this insulin (100 nmol/l) action was completely blocked by 50 μmol/l bumetanide (BMT) and 10 μmol/l amiloride (AML). This observation indicates that 100 nmol/l insulin activates BMT-sensitive Na+/K+/2Cl? cotransporter and AML-sensitive pathways. The stimulatory action of 100 nmol/l insulin on BMT-sensitive Na+/K+/2Cl? cotransporter was completely abolished by 10 μmol/l lavendustin A (LAV-A, an inhibitor of TK), however 100 nmol/l insulin could stimulate AML-sensitive pathways even in LAV-A (10 μmol/l)-treated cells. These observations indicate that the insulin (100 nmol/l) action on the BMT-sensitive Na+/K+/2Cl? cotransporter is mediated through TK-dependent pathways, while 100 nmol/l insulin requires a TK-independent pathway to show the stimulatory action on the AML-sensitive pathways. From these observations we conclude that TK-dependent and -independent pathways are involved in the insulin (100 nmol/l) signaling in fetal rat type II pneumocyte. 相似文献
87.
Enhanced polymer one-step staining (EPOS) is a novel, highly sensitive one-step immunostaining method. This simple and rapid technlque was applied to intra-operattve frozen diagnosis. The markers of choice were proliferating cell nuclear anmen (PCNA) and Ki-67 antigen. These cell prollferation markers were both identifiable in fresh frozen see tions of the human tonsil In approximately 7 min. The suitable staining sequences are as follows. Frozen sections prepared using 3-aminopropyitimethoxysilane-cpated glass slides are immediately fixed, without air drying, for 15s in a mixture of 50% formalin and 50% methanol for PCNA, and in 10% formalln for Ki-67 antigen. After a brief rinse in phosphate-buffered saline (PSS), sections are incubated with the EPOS antibody for 3 min, followed by PBS rinse for 1 min. The peroxidase activity is visualized in diaminobenzidine-H2 O2 solution containing 10mmol/L imidazole for 2 min. After a light rinse in tap water, the nuclei are briefly counterstained with 5% methyl green. When necessary, endogenous peroxi-dase blockage in 1% periodic acid solution for 1 min is added before the EPOS antibody incubation. This procedure is applicable to frozen sections of gastric cancers, malignant lymphomas, and brain, liver and peritoneal lesions in which differential diagnosis between benignancy and malignancy was required. 相似文献
88.
Ultrastructural,immunohistochemical and biochemical studies on amylase and ACTH producing lung cancer 总被引:1,自引:0,他引:1
Yutaka Yoshida Michio Mori Tomoko Sonoda Fumio Sakauchi Hiroyuki Sugawara Akira Suzuki 《Virchows Archiv : an international journal of pathology》1985,408(2-3):163-172
Summary Tumour tissue from a lung cancer patient who showed elevated serum amylase and adrenocorticotropin (ACTH) was studied ultrastructurally, immunohistochemically and biochemically. Histologically the tumour was a small cell carcinoma. On electron microscopic examination the tumour cells contained large zymogen-like granules within the cytoplasm. Furthermore, cells which possessed many small dense core granules of the endocrine type were also observed. It was of interest that the large zymogen-like granule-containing tumour cells had microvilli at the apical border, connected by desmosomes and forming lumina showing adenocarcinomatous differentiation. Electrophoretic analysis of the serum revealed that the major elevated amylase was of the salivary type with minor components. Immunostaining clearly demonstrated that most of the tumour cells possessed immunoreactive ACTH, whereas salivary amylase was only found in occasional clusters of the tumour cells. The results seem to indicate that the tumour showed both endocrine and exocrine characteristics - an amphicrine carcinoma, expressing amylase and ACTH simultaneously. 相似文献
89.
This report describes a 67-year-old male with inoperable gastric cancer accompanied by marked tissue and peripheral eosinophilia without evidence of allergic disorders or parasitic infestation. Autopsy revealed an advanced gastric cancer of scirrhous type with metastases to pancreas, bone marrow, ileum, lungs, and lymph nodes. Excessive numbers of mature eosinophils were present in univolved bone marrow, liver and spleen as well as among the signet ring cell component of the cancer in either primary or metastatic sites. The primary cancer also possessed a component of tubular adenocarcinoma which was associated with only a few eosinophils. Hence, we speculate that an eosinophil mobilizing (chemotactic and/or proliferating) factor (s) was produced by the signet ring cancer cells. 相似文献
90.
Katsuhiko Aoyama Kazuo Terashima Yutaka Imai Noriko Katsushima Yoshio Okuyama Katsuhisa Niikawa Takeo Mukada Katsuro Takahashi 《Pathology international》1984,34(2):375-388
The present paper deals with immunohistochemical and ultrastructural study of the lymph nodes of sinus histiocytosis with massive lymphadenopathy (Rosai and Dorfman, SHML) of a 12-year-old Japanese boy. This is the fourth case in Japan. Osseous manifestation was also found in the bilateral ulnae. With hallmarks of S-100 protein and interdigitating cytoplasmic extensions, the phagocytizing histiocytes proliferating in the sinuses were considered to be derived mostly from interdigitating cells in the paracortex or T cell dependent area, which have heretofore been regarded as nonphagocytizing. Furthermore, it is most interesting that lymphoid cells bearing thymic cortical cell-antigen (OKT 6) were increasingly recognized in the patient's peripheral blood. These results suggested that SHML is a specialized reactive histiocytosis analogous to histiocytosis X and histiocytic medullary reticulosis. 相似文献