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61.
Pituitary glands of chicken, from stages 20 (70 approximately 72 h of incubation) to 46 (20 days) of Hamburger and Hamilton (1951), were studied by immunocytochemical and histological stainings and India ink injection into blood vessels. Using the distribution pattern of 6 types of immunoreactive adenohypophyseal cells and the location of pituitary stalk as guideposts, we found how specific areas in the epithelium of Rathke's pouch differentiate into specific regions of the adenohypophysis at 20 days. In the sagittal plane, the walls of Rathke's pouch were tentatively divided into the upper part (A(1) + A(2)) and lower part (A(3)) of the anterior wall, and the posterior wall (P(1) + P(2) + P(3)). The cephalic lobe was mainly assembled by the proliferation of parenchymal cells in the areas A(2) + A(3) + P(2) of Rathke's pouch epithelia at 3 days of incubation. The caudal lobe was derived from A(1) + P(1) + P(3). The pars tuberalis was derived from A(1) + A(2). Thus, the avian adenohypophysis is established at 13 days, though the blood supply to the pars distalis is established at 20 days. Therefore, the cephalic lobe and caudal lobe of the pars distalis and the pars tuberalis of the chicken adenohypophysis are derived from specific areas of the cell cords of Rathke's pouch at 3 days of incubation.  相似文献   
62.
We describe the first case of a Trichosporon asahii infection of the lung characterized by an epithelioid granuloma with multinucleated giant cells. The patient died of respiratory failure due to lung fibrosis and lung cancer. Autopsy showed primary lung cancer with metastasis, lung fibrosis, and a focal infectious lesion containing the filamentous and yeast forms of a fungus. From its shape the fungus was judged to be Trichosporon, but unusual pathological findings revealed an epithelioid granuloma with multinucleated giant cells surrounding the hyphae and yeast cells. Immunohistochemical staining was performed using the specific Trichosporon spp. monoclonal antibodies and DNA identificationn was done by the PCR. The results showed this case to be a localized Trichosporon asahii infection. Hypersensitivity pneumonitis (HP) due to Trichosporon spp. with its pathological finding of inflammation with granuloma is common, but infections with granulomatous inflammation are extremely rare. This case suggests that Trichosporon infection may develop into granuloma with multinucleated giant cells.  相似文献   
63.
A rare case Is descrlbed of an Intramural sarcoma of the rlght common carotld artery coexistlng wlth adventitial inflammation and flbrosls, resembllng 'inflammatory aneurysm', which was resected from a 33-yearold Japanese woman who had presented with a pulsatile mass on the rlght side of the anterior neck. Grossly, the wall of the carotld artery showed an intimal tear with dlssectlon of the medla filled with thrombus. A graylsh area, abutting directly onto the dlssected space and Involving the media and inner adventltia, was composed of a-smooth muscle actin-positive and desmln-negative polygonal and splndle cells with large bluntended nuclei and coarse granular chromatin arranged Into a well-organized Interlacing bundle pattern. This portlon was thus considered to represent lelomyosarcoma. White to yellow-tan fibrotic tissue present in the adventitial area consisted of extensive lamellar fibrosis wlth scattered focl of lymphoplasmacytlc aggregates and obliterated arteries, and lacked atypical spindle and polygonal cells. These changes accorded with the histopathologlcal findlngs hitherto described in cases of 'inflammatory aneurysm', which is known to almost exclusively involve the abdominal aorta. We conslder this case unique In that the leiomyosarcoma involved an artery other than the aorta, wlth an 'inflammatory aneurysm'-like reaction in the same she. The posslble relatlonship between these two condltions Is dlscussed.  相似文献   
64.
Rat kidneys were perfused with anti-intercellular adhesion molecule-1 (anti-ICAM-1) monoclonal antibody prior to allo-transplantation. In the two strain combinations examined, LEJ-to-WKAH transplants resulted in accelerated graft loss, and no prolongation of graft survival. The accelerated graft logs was the resut of frequent occurrence of necrotizing arterttis wlthln the grafts. In contrast, TO-to-WKAH transplants resulted in no change In graft survival and no arteritis. Necratidng vasculitis in the LEJ-to-WKAH grafts was characterlzed by flbrinoid necrosis, collection of cellular infiltrates and serum macromolecular protein entrapment. The F(ab')2 form of anti-ICAM-1 antlbody partially preserved the antibody's capacity to accelerate graft loss. Therefore, although endothelial injury by Fc-mediated cytotoxicity may be involved in vascular damage, other mechanisms also come into play. The amount and distribution pattern of ICAM-1 antigen were identical in both TO and LEJ strains. Intravenous anti-CAM-1 antibody administration combined with lipopolysaccharide, Poly(1)-Poly(C), warm ischemia to the kidney, or subcutaneous immunization with allogeneic spleen cells, but without renal transplantation, did not generate necrotizing vasculitis or proteinuria. These observations plus our previous data on the rat liver transplantation model clearly show that graft perfusion with anti-ICAM-1 monoclonal antibody invokes extensive vascular damage within allografts by Fc-mediated and Fc-independent mechanisms, depending on the donor-to-host combination.  相似文献   
65.
A few studies have reported a correlation between magnesium and co-morbidity and mortality in end-stage renal disease. We investigated the prognostic value of serum magnesium concentration for mortality in 515 patients on maintenance hemodialysis (60 +/- 12 years, 306 males and 209 females; 24% diabetics). The patients underwent follow-up for 51 +/- 17 (mean +/- SD) months, and the relationship between the baseline magnesium concentration (mean of four months) and outcomes was analyzed statistically. During the follow-up period, there were 103 all-cause deaths, including 63 non-cardiovascular deaths. Kaplan-Meier analysis revealed that mortality was significantly higher in the lower magnesium group (< 2.77 mg/dL, i.e. < 1.14 mmol/L, n = 261), compared to that in the higher magnesium group (> or = 2.77 mg/dL, n = 254) (p < 0.001). Multivariate Cox proportional hazard analysis demonstrated that serum magnesium was a significant predictor for mortality (HR [per 1 mg/dL increase], 0.485 [95% CI, 0.241-0.975], p = 0.0424), particularly for non-cardiovascular mortality (HR 0.318 [95% CI, 0.132 to 0.769], p = 0.0110), after adjustment for other confounders, such as age, gender, hemodialysis duration, and the presence of diabetes. In conclusion, it is demonstrated that lower serum magnesium level is a significant predictor for mortality in hemodialysis patients, particularly for non-cardiovascular mortality, although the mechanisms remain to be explored in future studies. Factors affecting serum magnesium concentrations should be investigated in terms of better survival, including dietary magnesium intake. Further extensive studies may be also needed for possible reconsideration of the current dialysate magnesium concentration (1.0 mEq/L, i.e. 0.50 mmol/L used in most countries), one of the strong contributors to the serum magnesium concentrations of dialysis patients.  相似文献   
66.
Association between HLA and Japanese patients with rheumatoid arthritis   总被引:12,自引:0,他引:12  
Japanese patients with rheumatoid arthritis (RA) were observed to have a statistical association with HLA-DR4, MT3. Strong association between the clinical severity of RA and HLA was also observed. Male patients had a stronger association with HLA than female patients. Males are more resistant to RA than females. This suggested that the threshold of liability for RA is higher in males than in females. Japanese patients with RA with systemic vasculitis were negative for HLA-Bw44 and had antilymphocytotoxic autoantibody, indicating that RA with systemic vasculitis is different in etiology from RA without systemic vasculitis.  相似文献   
67.
To examine early intercellular junction changes caused by treatmentwith 9, 10-dimethyl-l, 2-benzanthracene (DMBA), rat lingualepithelium was cultivated in isolation and observed by electrophysiological,freeze-fracture and whole-mount electron microscopy. Electrophysiologicalmeasurements showed a transient decrease in membrane potentialof -10.2 mV 6 h after the treatment. It returned to almost thesame level as that of the control group 1 day later. Six hoursafter treatment, input resistance decreased rapidly to 5.3 Mbut increased to 18.0 M 12 h after treatment. Transient reductionof input resistance and membrane potential occurred prior tothe decrease in the coupling ratio 6 h after treatment withDMBA. In freeze-fracture replicas, the number of gap junctionsdecreased by 45% of the control value 6 h after treatment withDMBA. At 12 h and thereafter, the number and area of gap junctionssubsequently decreased by 60–80% of the control value.Alterations in the number and area of desmosomes were similarto those of the gap junctions. The formation of epithelial cytoskeletons,partially devoid of the 2–4 and 5–8 nm filamentswas also observed. A decrease in the density of filament networksbeneath the plasma membranes was especially apparent. Treatmentwith a carcinogen brought about morphological cellular changesas early as 6 h after treatment, and such early changes mighttrigger metabolic cellular abnormalities. Affected cells appearto move away from normal cells in a process of repeated destructionand revision of intercellular junctions, and cytoskeletons.  相似文献   
68.
The aim of this research was to reveal the characteristics of gut microbiome altered by acarbose intervention in Japanese patients with type 2 diabetes (T2D) and its possible association with habitual dietary intake. Eighteen patients with T2D were administered acarbose for four weeks. The abundances of two major phyla, namely Actinobacteria and Bacteroidetes, were reciprocally changed accompanied by the acarbose intervention. There were also significant changes in the abundances of ten genera, including the greater abundance of Bifidobacterium, Eubacterium, and Lactobacillus and the lower abundance of Bacteroides in the group after the intervention than that before the intervention. Hierarchical clustering of habitual dietary intake was performed based on the pattern of changes in the gut microbiota and were classified into distinct three clusters. Cluster I consisted of sucrose, cluster II mainly included fat intake, and cluster III mainly included carbohydrate intake. Moreover, the amount of change in Faecalibacterium was positively correlated with the intake of rice, but negatively correlated with the intake of bread. The intake of potato was negatively correlated with the amount of change in Akkermansia and Subdoligranulum. Acarbose altered the composition of gut microbiome in Japanese patients with T2D, which might be linked to the habitual dietary intake.  相似文献   
69.
Velocity data from tissue Doppler imaging (TDI)can provide valuable information on regional leftventricular wallmotion. Validation of TDImyocardialvelocity measurements has been carried out indirectlyfrom gray- scale M- mode images,and discrepancieshave been reported.Mc Dicken[1] and Miyatake etal[2 ]have reported the accuracy and validity of the TDIsystem using a rotating sponge model.However theoverall motion of the heart should be considered.Inthe present study,we described a new TDI…  相似文献   
70.
We compared the rate of selective shunt and pattern of monitoring change between single and dual monitoring in patients undergoing carotid endarterectomy (CEA). A total of 121 patients underwent 128 consecutive CEA procedures. Excluding five procedures using internal shunts in a premeditated manner, we classified patients according to the monitoring: Group A (n = 72), patients with single somatosensory evoked potential (SSEP) monitoring; and Group B (n = 51), patients with dual SSEP and motor evoked potential (MEP). Among the 123 CEAs, an internal shunt was inserted in 12 procedures (9.8%) due to significant changes in monitoring (Group A 5.6%, Group B 15.7%, p = 0.07). The rate of shunt use was significantly higher in patients with the absence of contralateral proximal anterior cerebral artery (A1) on magnetic resonance angiography (MRA) than in patients with other types of MRA (p <0.001). Significant monitor changes were seen in 16 (12.5%) in both groups. In four of nine patients in Group B, SSEP and MEP changes were synchronized, and in the remaining five patients, a time lag was evident between SSEP and MEP changes. In conclusion, the rate of internal shunt use tended to be more frequent in patients with dual monitoring than in patients with single SSEP monitoring, but the difference was not significant. Contralateral A1 absence may predict the need for a shunt and care should be taken to monitor changes throughout the entire CEA procedure. Use of dual monitoring can capture ischemic changes due to the complementary relationship, and may reduce the rate of false-negative monitor changes during CEA.  相似文献   
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