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101.
The lymph-node yields in specimens resected for colorectal adenocarcinoma show considerable variations, raising the question whether the minimum lymph-node number recommended by the UICC (International Union Against Cancer) for pN0 classification represents an appropriate quality standard for specimen work-up. The number of pericolic lymph nodes recovered from 568 archival surgical colorectal carcinoma specimens located in the sigmoid or upper rectum showed a highly statistically significant correlation with both the pT category and the presence of metastases (P<0.0005). The median lymph-node yield in standardized (i.e., resembling in size surgically removed cancer specimens) tumor-free specimens obtained during autopsies was 13 lymph nodes, compared with 20.5 when diverticula were present and more than 30 in specimens with chronic inflammation or from patients with systemic infections. In 48 pT2 and pT3 carcinoma specimens prospectively dissected in the same way, median numbers of 18 (pT2) and 23 (pT3) lymph nodes were detected (range between 8 and 39 nodes). The lymph-node numbers recommended in previous studies and by the UICC often seem to be too low to declare a specimen free of metastases. Although the great variation in lymph-node counts requires the recovery of all lymph nodes for pN0 classification, recommendations considering the pT status and additional factors like diverticula and inflammatory changes can be useful as a quality standard for specimen work up.  相似文献   
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对12例经病理学专家会诊、从病变上认定的淋巴结“结节病”石蜡包埋组织,应用结核杆菌DNA特异性序列片段的聚合酶链反应(M.TB-PCR)技术、BCG免疫组化(BCG-IHC)技术和抗酸染色(AF)进行了分支杆菌/结核杆菌检测。在这12例考虑为“结节病”的病例中:有1例呈BCG-IHC和M。TB-PCR两项阳性;另1例呈AF、BCG-IHC和M.TB-PCR三项阳性。研究结果提示:(1)某些结核性淋巴结炎可呈结节病样病变;(2)淋巴结结节病很可能与分支杆菌/结核杆菌感染有关。  相似文献   
104.
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   
105.
Young adult and old mice were immunized by footpad injection of dinitrophenyl-conjugated bovine gamma-globulin (DNP-BGG) in complete Freund's adjuvant. A comparison of lymph node weight and total number of nucleated cells per lymph node as a function of time after antigen injection demonstrated a significantly greater absolute increase in lymph node weight and peak number of nucleated cells per lymph node in young-adult than in old animals. However, as judged by this increase in total nucleated cells, other than being delayed in old mice, the magnitude of these in situ proliferative responses appeared comparable for young-adult and old mice. That is, the antigen-stimulated to non-stimulated cell ratio did not differ significantly between young-adult and old animals. This was because lymph nodes from old animals prior to antigen injection always weighed less and had fewer numbers of nucleated cells compared with young-adult animals. Therefore, the in vitro cellular proliferative response of three T-cell-enriched lymphocyte subpopulations from young-adult and old mice was further characterized. This was done by measuring [3H]thymidine incorporation following antigen- (DNP-BGG)- or mitogen-[phytohemagglutinin (PHA) or Concanavalin A (Con A)]-induced proliferation and assessing their quantitative and/or qualitative requirements for macrophages. In contrast to the markedly reduced proliferation of the two T-cell subpopulations from popliteal lymph nodes which respond to PHA and Con A in old animals primed 21-days earlier with DNP-BGG, antigen-induced in vitro cellular proliferation of the small T-cell subset in old mice specifically responsive to the immunizing antigen DNP-BGG always responded as well as, if not better than, cells from young-adult mice.  相似文献   
106.
The febrile reaction in dogs, as established experimentally, is accompanied by a significant intensification of the lymph flow. Metapyrin provides a strong boost to the lymph circulation, improving exchange processes between the blood and tissues Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N o 2, pp. 180–181, February, 1994  相似文献   
107.
The purpose of this investigation was to test the hypothesis that activation of the immune system in rats will lead to changes in the density of innervation in lymph nodes. In order to reduce the variability between animals, the rats were reared under sterile conditions and immunostimulation was effected by subcutaneous application of bovine albumin in a region draining to the axillary lymph nodes of both sides. Control animals received an equivalent application of sterile physiological saline. The animals were sacrificed 10 days and 27 days and 4 months after immunostimulation. The nerves in the axillary lymph nodes were quantified by light microscopy in silver impregnated sections and at the ultrastructural level on ultrathin sections. The survival times were chosen so that the first group was in the ascending phase of antibody production, the second group at the peak, and the third group in the declining phase. Both at the light and ultrastructural levels, there were statistically significant differences in the density of innervation of medulla between the groups, with a particularly pronounced increase in the group 4 months after immunostimulation. At the ultrastructural level, there was also an increase in the density of incompletely ensheathed axonal profiles in the parenchyma of the medulla, while the nerves associated with blood vessels were not increased. We conclude that immunostimulation leads to morphological changes in the innervation of the medulla of axillary lymph nodes, that are consistent with the concept of functional activation of the autonomic nervous system through the immune system. © 1994 Wiley-Liss, Inc.  相似文献   
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The immunosuppressive effect of CS-A was first studied in the assay for local GvHR. 3 x 106 viable spleen cells from LEW rats were injected into one foot pad of LEW x BN hybrids and both PLN were weighed 7 days later. Treatment of the recipients with 3 doses of 50 mg/kg/day of CS-A suppressed this local GvHR. The effect was more pronounced when treatment started at the time of cell transfer rather than a few days before peak response. In-vitro incubation of the cellular inoculum with CS-A also prevented local GvHR. Histology of the PLN confirmed the quantitative results expressed by the PLN index. CS-A was further investigated in the EAE model in LEW rats. It protected rats sensitised with spinal cord emulsified in complete Freund's adjuvant for as long as they were treated with CS-A. Treatment delayed until after the appearance of EAE also markedly improved their condition. Oral treatment of recipients with 50 mg/kg/day CS-A prevented the development of adoptive EAE following the transfer of lymphoid cells conditioned in vitro. The presence of 0.1-1.0 μg CS-A in the medium of the sensitised lymphoid cells also inhibited the adoptive transfer of EAE. Finally, if the cells for the adoptive transfer were derived from CS-A-treated sensitised donors, they failed to induce EAE. Histological examination supported the symptomatic findings  相似文献   
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