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991.
A case of primary gastric T-cell lymphoma, which was positive for granzyme B, is reported. The patient was a 47-year-old Japanese female who complained of a dull upper abdominal pain. Radiographic and endoscopic examinations revealed an ulcerative infiltrative lesion in her stomach. Following the confirmation of a high-grade malignant lymphoma, a distal gastrectomy with regional lymph nodal dissection was performed. The histology of the gastric lesion revealed a malignant lymphoma of the diffuse pleomorphic type without lymph nodal involvement. Immunohistochemistry revealed that the tumor cells were positive for LCA, CD3, TIA-1 and granzyme B, but were negative for CD4, CD8, CD56, CD30, L-26, EMA, TCR alpha/beta and TCR gamma/delta. Because the tumor cells showed T cell nature with cytotoxic activity proved by TIA-1 and granzyme B, and without evidence of further maturation of T cell, a malignant lymphoma originating from extrathymic-derived T cells was suggested.  相似文献   
992.
Bath application of the inhibitors of phospholipases, nordihydroguaiaretic acid (NDGA) and p-bromophenacyl bromide (BPB), to the rat hippocampal slices suppressed long-term potentiation (LTP) in Schaffer/commissural-CA1 pyramidal synapses. On the other hand, neither of the two inhibitors suppressed LTP in mossy fiber-CA3 pyramidal cell synapses. BPB did not suppress phosphatidylinositol-specific phospholipase C (PI-PLC) activity of the slices. These results suggested that the mechanisms of LTP were quite different in the CA1 and CA3 subfields of rat hippocampus: in CA1, the involvement of an arachidonate metabolism was strongly suggested, whereas in CA3, an arachidonic acid cascade may not be necessary for LTP.  相似文献   
993.
The genetic polymorphism of orosomucoid (ORM) and alpha-2-HS-glycoprotein (AHSG) were studied in Thai, Sri Lankan and Paraguayan populations using isoelectric focusing. Gene frequencies in these populations were compared with those in other populations. Four new ORM variants were detected:ORM1 * 15 in Thai,ORM1 * 16 in Paraguayan,ORM2 * 21 andORM2 * 22 in Sri Lankan.  相似文献   
994.
Besides the larger Cl channel with a single channel conductance of about 45 pS, a small channel was observed in the luminal membrane of the dogfish rectal gland [9]. In cell excised (inside out) patches with NaCl solution on both sides, the latter channel had a single channel conductance of 11±1 pS (n=21), and its current-voltage relationship was linear in the voltage range+90 to –90 mV. The open state probability increased moderately with negative clamp potentials. Ionic replacement studies revealed a high selectivity of Cl over gluconate, sulfate, and iodide, whereas bromide was permeable to some extent. Also the channel is impermeable for Na+. The Cl channel blocker 5-nitro-2-(3-phenylpropylamino)-benzoate did not affect this small conductance Cl channel. It can be concluded that the luminal membrane of stimulated rectal gland cells possesses two types of Cl channels, which differ markedly in their characteristics.Supported by Deutsche Forschungsgemeinschaft Gr 480/8 and by NSF and NIH grants to the MDIBL  相似文献   
995.
Infertile women without any inherent female infertility factorsand able to secrete normal cervical mucus were studied prospectivelyin relation to post-coital sperm—mucus penetration (PCT)and their partner's seminal analysis, excluding men with azoospermia.Time-specific cumulative conception rates calculated as forlife-table analysis were related to each measured seminal variableon routine analysis of 2–3 samples (volume, density, proportionwith progressive motility, and proportion with normal morphology);to various derivatives from combinations of these variables;to seminal findings after vital staining; and to the PCT results.The best seminal predictor of fertility was the motile normalsperm density (MNSD), the 18 month conception rates being 57.4%+ 4.6 (SE) and 30.2% + 5.9 (ratio 1.9, P < 0.001) above andbelow a derived threshold value of 4 x 106/ml. The PCT led torates of 55.6% ± 4.3 and 14.9% ± 5.1 (ratio 3.73,P < 0.001) for positive and negative results, respectively.The PCT also gave rise to a significantly distinct intermediatepoor-psitive sub-group (conception rate 30.6% ± 9.0).Seminal analysis (the MNSD) did not affect the conception rateassociated with a positive PCT but helped to discriminate furtherwith a negative PCT (conception rates 22.5% ± 8.7 withan MNSD above 4 x 106/ml versus 5.6% ± 4.8 below, P <0.05). The PCT was the single best predictor of fertility butseminal analysis (the MNSD) was of additional value after anegative PCT.  相似文献   
996.
Thirty-two women with polycystic ovary syndrome (PCOS) wereallocated to two antiandrogen treatment regimens; 28 women completedthe trial. Twenty women were treated with ethinyloestradioland cyproterone acetate (EO-CA) cyclically for 6 months andeight women were treated with the gonadotrophin releasing hormone(GnRH) analogue, goserelin for 6 months. Effects on hirsutism,insulin sensitivity (estimated by glucose clamp technique),blood lipids and hormones were measured. Women treated withEO-CA showed a reduction in hirsutism (P <0.05), and decreasedserum androgen concentrations (P <0.001) as well as reducedinsulin sensitivity (P <0.05). In women treated with goserelin,serum androgen concentrations also decreased (P <0.001),but there was no significant reduction of hirsutism. This group,however, showed an improved insulin sensitivity (P <0.05)despite an unchanged body mass index. Bone mineral density wasunaltered in both treatment groups. The reduction in androgenconcentrations caused by EO-CA was not paralleled by increasedinsulin sensitivity, most probably due to the effect of ethinyloestradiolper se. In contrast, the reduction in androgen concentrationsby goserelin was accompanied by an improved insulin sensitivity.  相似文献   
997.
新生乳牛淋巴器官的组织学和组织化学研究   总被引:1,自引:0,他引:1  
张登荣  茅亨 《解剖学报》1992,23(4):421-424
  相似文献   
998.
Single fibres of three different types, which had been characterized histochemically with regard to differences in myofibrillar adenosine triphosphatase (ATPase) activity and its pH stability, were microdissected from freeze dried preparations of the closer muscle in walking legs of the crab Eriphia spinifrons. Shortening velocities were determined in slack tests and under constant load conditions in maximally Ca2+-activated skinned muscle fibres. Force/pCa relationships were also measured for the different types of fibres. Compared with data on vertebrate muscles, all crab muscle fibres required large length changes to reach zero force and showed low Ca2+ sensitivity for isometric force generation. The length/time relationship obtained from slack tests had a biphasic course. Maximal velocity of filament sliding differed in the three types of fibres investigated. The filament sliding of type IV fibres was about 3 times faster than that of type I fibres. The values obtained for type II fibres ranged in between. These data are positively correlated with myofibrillar ATPase activity determined histochemically. Ca2+ sensitivity of force generation was lowest in the fast type IV fibres. It was high in the slow type I and the faster contracting type II fibres. Ca2+ sensitivity in crab muscle seems not to be correlated with speed of shortening.  相似文献   
999.
One-hundred-and-twenty-three in-vitro fertilization (IVF) cycles were analysed in order to clarify the influence of strictly normal morphology (SNM) of spermatozoa on IVF outcome. SNM was defined using strict criteria according to Kruger with our modifications. The IVF cycles studied were divided into three groups: %SNM less than 12% (13 cycles), 12 less than 40% (68 cycles), greater than or equal to 40% (42 cycles). The cleavage rates per oocyte were higher in the groups with 12-40% and greater than or equal to 40% of %SNM than in the group with %SNM less than 12%. The embryo transfer rate per cycle increased with increasing %SNM. The overall pregnancy rate per cycle increased with increasing %SNM (7.7% in %SNM less than 12%, 22.1% in 12-40% of %SNM, and 40.5% in %SNM greater than or equal to 40%). The ongoing pregnancy rate per cycle also increased with increasing %SNM (7.7% in %SNM less than 12%, 14.7% in 12-40% of %SNM, and 31.0% in %SNM greater than or equal to 40%). The miscarriage rate was lower in %SNM greater than or equal to 40% (23.5%) than in 12-40% of %SNM (33.3%). It was suggested that %SNM is a good predictor of IVF outcome.  相似文献   
1000.
Summary Hemoglobin (Hb) M-Saskatoon, a variant of methemoglobin, is characterized by mild hemolysis. It is caused by the substitution of a histidine by a tyrosine at the 63rd amino acid residue of the -globin chain. Amplification and sequence analysis of genomic -globin DNA from an Indonesian boy diagnosed as having the more severe disease thalasemia demonstrated the presence of a C to T transition at nucleotide 473 in one of the two -blogin genes resulting in a histidine to tyrosine substitution at 63rd residue. This amino acid change matched with that reported in Hb M-Saskatoon. This nucleotide change abolished a recognition site for the restriction endonucleaseNlaIII.NalIII digestion of the corresponding -globin DNA amplified from the patient's parents indicated that the mutation was inherited through from his mother. This result shows that the world-wide distribution of Hb M-Saskatoon extends to Indonesia, where it was not previously identified. Possible causes of the unusually severe symptoms observed in the case are discussed.  相似文献   
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