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81.
We report herein the case of a 32-year-old woman who underwent distal gastrectomy with D2 lymph node dissection for gastric cancer. Microscopic examination of the resected specimen revealed signet-ring cell carcinoma of the stomach with lymph node metastases, and endosalpingiosis in the normal lymph nodes. There was no evidence of malignancy in the peritoneal cavity. To our knowledge, no other case of endosalpingiosis in the lymph nodes along the stomach has ever been reported. The possible significance of endosalpingiosis is discussed following this case report.  相似文献   
82.
Nefiracetam, a nootropic agent, enhanced the slope of field excitatory postsynaptic potentials in the CA1 region of rat hippocampal slices to about 170% of basal levels, being evident still at 4-h washing-out of the drug. A similar sustained enhancement (>/=16 h after i.m. injection with nefiracetam) was observed in the population spikes recorded from the granular cell layer of the intact mouse hippocampus. Saturation of the enhancement in the synaptic strength occluded potentiation obtained with long-term potentiation (LTP) induced by high-frequency (tetanic) stimulation, and vice versa. Interestingly, the facilitatory action of nefiracetam was blocked by either the nicotinic acetylcholine (ACh) receptor antagonists, alpha-bungarotoxin and mecamylamine, or the selective protein kinase C (PKC) inhibitor, GF109203X, but in contrast, it was not affected by D-2-amino-5-phosphonovaleric acid (APV), a selective N-methyl-D-aspartate (NMDA) receptor antagonist. The results of the present study suggest that nefiracetam, whereas the action is independent of NMDA receptors, induces an 'LTP-like' facilitation of hippocampal synaptic transmission as a consequence of modulation of nicotinic ACh receptors and PKC. This may represent a likely mechanism underlying the cognition-enhancing actions of nefiracetam.  相似文献   
83.
84.
1. Occurrence of miniature endplate potentials (MEPP) in the sartorius muscle of Rana catesbiana in high Mg2+ Ringer solution were observed in standard intracellular recording. Intervals and amplitudes of sequentially occurring MEPP were registered and analyzed. 2. Interval histograms of a time series of MEPP showed exponential-like pattern as reported in the classical study by Fatt and Katz (1952). The cumulative distribution of the intervals plotted in logarithmic axes showed two distinct phases. In shorter intervals (< 1s), curve along exponential decay was observed, and in longer intervals (> or = 1s) linear decay can be seen. The latter power-law relation gave dimensions of 4.111 +/- 0.812 (mean and S.D.). Self-similarity in longer range implies a time-scale invariant nature and may suggest fractal nature in restoration process of synaptic vesicles, while exponential decay in the short time interval range implies random release of transmitter packet from the readily releasable pool. 3. Fluctuation of amplitudes in sequentially occurred MEPP were analyzed according to Higuchi's cumulative route-length analysis. The estimates for sequential amplitude curve showed the power-law relation in a logarithmic plot whose inclination (= D) estimated with linear regression analysis was 1.996 +/- 0.007 (mean and S.D.). This results indicate that fluctuation in the amplitude of MEPP shows possible maximum complexity as a graphic curve in 2-D plane. Similar result was obtained for fluctuation of intervals of successively occurring MEPP.  相似文献   
85.
BACKGROUND: Donor-specific immunosuppression is important in transplantation surgery. We examined the immunosuppressive effects of donor splenocytes administered postoperatively into the jejunum and the effect of such treatment on the survival of heterotopic vascularized cardiac allograft in rats. METHODS: Lewis (LEW, RT-1l) recipient rats were treated with 5x10(7) Brown Norway (BN, RT-1n) donor splenocytes for 5 days orally, intrajejunally, or subcutaneously. The immune responses of LEW treated with either donor BN or irrelevant Wistar King A (WKA, RT-1k) were examined by mixed lymphocyte reaction (MLR) and delayed type hypersensitivity (DTH). The effect of postoperative enteral treatment for 6 days with suboptimal dose of cyclosporine (CsA) on heterotopic cardiac allotransplantation was investigated. We measured the production of cytokines (interleukin [IL]-2, IL-4, IL-10, and interferon-gamma [IFN-gamma]) in the supernatant of MLR by ELISA. The effect of intravenous dose of GdCls to block Kupffer cell function was also investigated before the administration of splenocytes. RESULTS: MLR and DTH responses were strongly inhibited in a BN-restricted manner after jejunal or oral feeding of donor BN splenocytes but not by subcutaneous injection or injections by any routs of WKA splenocytes. The effect was more prominent in jejunal than oral feeding. Immunosuppression was associated with a significant inhibition of IL-2 and IFN-gamma production and increased concentrations of IL-4 and IL-10 in MLR supernatants. Immunosuppression was abrogated by pretreatment with GdCl3. Postoperative intrajejunal feeding of donor splenocytes with CsA significantly prolonged cardiac allograft survival time (18.7+/-7.3 vs. 9.9+/-1.7 days for control animals). CONCLUSION: Jejunal administration of splenocytes produces donor-specific immunosuppression and prolongs cardiac allograft survival. Our results suggest the involvement of T helper (Th) 2 cytokines and Kupffer cells in the induction of immune hyporesponsiveness, and indicate that this method represents a unique approach for induction of donor-specific immunosuppression.  相似文献   
86.
87.
BACKGROUND AND OBJECTIVE: The holmium:YAG (Ho:YAG) laser can be used not only for soft tissue but also for hard tissue such as urinary calculi. The objective of this study was to assess the usefulness of the Ho:YAG laser for endoscopic lithotripsy in patients with urinary tract stone. STUDY DESIGN/MATERIASL AND METHODS: Of 102 procedures performed among 96 patients, 88 were transurethral ureterolithotripsy (TUL), seven were percutaneous nephrolithotripsy, and seven were transurethral cystolithotripsy. Six patients had bilateral stones. The fragments were reduced as much as possible with the Ho:YAG laser. RESULTS: The efficacy rate of the 102 lithotripsy procedures was 93%. With respect to the effect of TUL, the efficacy rates of 40 procedures for the proximal ureter, 18 procedures for the midureter, and 30 procedures for the distal ureter were 85%, 94%, and 100%, respectively. CONCLUSION: The Ho:YAG laser produced a sufficiently strong lithotripsy force on all stones. The results of this study indicate that lithotripsy of urinary tract stones with the Ho:YAG laser can achieve a clinical outcome equivalent to or exceeding that of pulsed dye laser lithotripsy. The Ho:YAG laser is a multipurpose laser and thus is a cost effective and very useful means for endoscopic lithotripsy of urinary tract stones.  相似文献   
88.
Naito M  Matsuoka M  Ohara N  Nomaguchi H  Yamada T 《Vaccine》1999,18(9-10):795-798
The proteins in culture filtrate derived from Bacillus Calmette-Guérin (BCG) were examined for protection against infection by Mycobacterium leprae. Immunization with the major secreted proteins, antigen 85 complex (Ag 85) A, B and C, induced effective protective immunity against multiplication of M. leprae in the foot pads of mice. The most effective protection was observed when mice were immunized with Ag 85A. A single immunization with Ag 85 could induce antigen-specific interferon gamma (IFNgamma) synthesis and more effective protection than live BCG vaccine. This study demonstrates that Ag 85 is an important immunoprotective molecule against leprosy infection.  相似文献   
89.
Antigenic epitopes of carcinoembryonic antigen (CEA) and non-specific cross-reacting antigen (NCA) were analysed in relation to their domain structures [domains N, I (A1-B1), II (A2-B2), III (A3-B3) and M for CEA and domains N, I (A1-B1), and M for NCA]. We reconstructed cDNAs for CEA-N, CEA-N-I, CEA-N-I-II, CEA-N-I-II-III-M (CEA-whole), NCA-N, NCA-N-I and NCA-N-I-M (NCA-whole), which were expressed in Chinese Hamster Ovary (CHO) cells. The recombinant proteins were purified by immunoadsorption and gel filtration. Their mol. wts judged from Western blotting were 17,000-26,000 for CEA-N, 70,000 for CEA-N-I, 150,000 for CEA-N-I-II, 165,000 for s-CEA-whole which was spontaneously released from cells into culture medium, 180,000 for p-CEA-whole which was solubilized with phosphatidylinositol specific phospholipase C (PI-PLC) from cells, 18,000-25,000 for NCA-N, 63,000 for NCA-N-I, and 96,000 for p-NCA-whole which was solubilized with PI-PLC from cells. The divergence of the observed mol. wts from those calculated from cDNA sequences seems to indicate that these recombinant proteins are highly N-glycosylated. By enzyme immunoassays, the immunoreactivities of the purified recombinant proteins were tested with 25 distinct anti-CEA monoclonal antibodies (MAbs), each representative of 25 different subgroups within five groups (Groups 1-5) previously classified by us in terms of the reactivity with CEA and CEA-related antigens. Twenty-one MAbs previously shown to react with different protein epitopes of the CEA molecule allow to define six groups (A-F) of epitopes according to their expression by different domains of the CEA and NCA molecules. Among four epitopes common to CEA and NCA, two were found to be present on domain N (Group A) and two on domain I (Group B). Among 15 epitopes absent from NCA but expressed by CEA and normal fecal antigens (NFAs), four were on domain N (Group C), five on domain I (Group D) and six on domain II (Group E). Two epitopes were previously described as "CEA distinctive", because they were recognized by MAbs reacting with CEA but not with the NFAs. These two epitopes (Group F) were found to be expressed by p-CEA-whole but not by s-CEA-whole. The latter results suggest that the Group F epitopes are located on a part of the domain III close to the anchoring device of the CEA molecule.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
90.
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