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31.
N. Tsuchikame Y. Ishimaru S. Ohshima M. Takahashi 《Virchows Archiv : an international journal of pathology》1993,422(4):337-340
We report three cases of fundic gland polyposis in the stomach identified in three patients who were related. Grossly the numerous polyps covered an area limited to the body and fundus of the stomach, no polyps were found in the antrum, duodenum, colon, or rectum, and histologically, the gastric lesions consisted of numerous hamartomatous polyps, characterized by proliferation of the fundic and cystic glands. The gastric lesions were identified in families without polyposis coli. This type of fundic gland polyposis has never been documented before in the literature. 相似文献
32.
33.
34.
The site and concentration dependence of the blocking effect of Ba2+ onNecturus gallbladder epithelium has been investigated. A new approach was used which combines time-dependent electrical cell coupling
analysis with intermittently performed measurements of transepithelial and apparent intracellular impedance. From the coupling
pulse data the sum of apical and basolateral membrane conductances is obtained, which is then held constant during fitting
of the impedance data. This combination technique yields more reliable estimates of apical and basolateral membranes resistances
(R
a,R
bl) and of tight junction resistance (R
j) than our previous impedance analysis technique. Using the new approach we have found that luminal Ba2+ concentrations between 0.5 and 1.0 mmol/l increaseR
a with saturation-type kinetics without affectingR
bl andR
j, while higher luminal Ba2+ concentrations progressively increaseR
j. Corresponding effects were observed under serosal Ba2+. The results validate the new impedance analysis approach and demonstrate that millimolar concentrations of Ba2+ block tight junction conductances. Accordingly, Ba2+ can no longer be considered a tool to exclusively alter cell membrane resistances in epithelia. 相似文献
35.
36.
Properties and regulation of chloride channels in cystic fibrosis and normal airway cells 总被引:4,自引:0,他引:4
Karl Kunzelmann Hermann Pavenstädt Rainer Greger 《Pflügers Archiv : European journal of physiology》1989,415(2):172-182
The present study examines the properties of Cl–channels in cultured respiratory cells of cystic fibrosis (CF) patients and normal (N) individuals. In excised membrane patches the conductances for CF and N Cl– channels were larger at positive as compared to negative clamp voltages (V
c): 74±2.6 (V
c > 0) and 47±2.0 pS (V
c < 0) for CF (n= 57) and 69±3.6 (V
c > 0) and 45±2.3 pS (V
c < 0) for N (n=35). The open probability (P
o) of the channel increased markedly with depolarization. Both the voltage dependence of the conductance and of P
o contribute to the outward rectification of the channel. The time histogram analysis reveals two open and two closed time constants. The selectivity of the channel was Cl–=Br– =I– > NO
3
–
gluconate. The channel was inhibited reversibly by 5-nitro-2-(3-phenylpropylamino)-benzoate (NPPB) at 10–7 mol/l to 10–5 mol/l. While Cl– channels were present in cell attached patches of N cells, they were absent in those of CF cells. The mean conductance for cell attached (N) Cl– channels was 76±3.2 pS for positive clamp voltages (V
c) and 46±3.9 pS for negative V
c (n=8). When the membrane patches were excised from CF cells Cl– currents appeared spontaneously (n=19). The immediate appearance (within 1 s) of Cl– channels after excision was observed at positive (n=6) as well as at negative clamp voltage (n=13). Excision activation of CF Cl– channels was observed at low (< 10–9 mol/l) or high (10–3 mol/l) calcium activities on the cytosolic side of the excised patch. Variation of the Ca+ activity (< 10–9–10–3 mol/l) or pH (6.5–8.5) on the cytosolic side exerted no effects on these Cl– channels. These results suggest that Cl– channels are present in the apical membrane of CF and N respiratory cells but they seem to be inhibited in intact CF cells. Excision of the patch and hence removal of the cytosolic inhibitor leads to an activation of Cl– channels. The Cl– channels in excised patches of N and CF cells have identical properties. 相似文献
37.
Igor Babaryka 《Virchows Archiv : an international journal of pathology》1978,377(2):181-187
Summary A polypoid tumor was surgically removed from the second part of the duodenum of a 56-year-old male. The main body consisted of large epithelioid cells arranged in an adenoma like pattern of strands and nests. These cells were argyrophil and had marked nonspecific esterase activity. Unmyelinated nerves with proliferated Schwann cells accompanied these epithelioid cells together with scattered gangliocyte like elements. Ultramicroscopically, the epithelioid cells were seen to contain round electron dense granules, 150 nm in diameter on average. The tumor is considered to be a nonchromaffin paraganglioma, as it probably developed from paraganglion cells associated with small arteries or branches of the vagus nerve, or from the undifferentiated pluripotent APUD cells of the duodenum. 相似文献
38.
L. J. Jennings G. M. Salido M. -J. Pozo J. S. Davison K. A. Sharkey R. W. Lea J. Singh 《Inflammation research》1995,44(10):447-453
We have investigated the effects of histamine on motility of the gallbladder and characterized the receptor types involved. Histamine and the histamine H1-receptor agonist, 2-thiazolylethylamine (2-TEA) contracted the isolated guinea-pig gallbladder strip in a dose dependent manner. The contractile response to histamine was shifted to the right by the H1-receptor antagonist, mepyramine. In pre-contracted gallbladder strips, the H2-receptor agonist dimaprit reduced the tension generated in a dose dependent fashion. The histamine H2-receptor antagonist, ranitidine shifted the histamine concentration effect curve to the left and attenuated the dose dependent relaxations elicited at high concentrations. The histamine H3-receptor agonist, (R)--methylhistamine (RMHA) elicited dose dependent contraction of the tissue which was significantly inhibited in the presence of mepyramine. The effects of electrical field stimulation (EFS) on the strips were not significantly altered by the presence of RMHA (10–10–10–7 M) indicating little pre-synaptic H3 activity in this tissue. Histamine immunoreactivity (IR) was detected in gallbladder whole mount preparations of the mucosa and the muscularis/serosa. The histamine IR appeared cell bound in cells of varying morphological characteristics but no IR was detected in nerve fibres or cell bodies (ganglia). Alcian blue staining was consistent with the distribution of histamine IR cells as mast cells. The results indicate that histamine is distributed in the guinea-pig gallbladder and it can regulate contractile activity via activation of H1 and H2 but not H3 receptors. 相似文献
39.
目的探讨超声诊断输尿管下段息肉的临床应用价值。方法对12例经输尿管镜或膀胱镜检查、病理检查证实为输尿管下段息肉(其中男性8例,女性4例,年龄17~60岁,平均年龄32.6岁;病程1个月~4年。左侧9例,右侧3例,合并输尿管结石4例,膀胱结石2例,肾结石1例,息肉自输尿管口部分脱入膀胱4例,随输尿管喷尿节律性脱入膀胱2例)的患者超声及临床资料进行回顾分析。结果超声对输尿管下段息肉的诊断符合率为58.3%(7/12)。误诊为输尿管癌3例,膀胱肿瘤2例,误诊率为41.7%(5/12)。其中合并输尿管结石4例,膀胱结石2例,肾结石1例。病理诊断为炎性增生性息肉9例,纤维性息肉3例。结论超声是输尿管下段息肉的首选筛查方法,对合并阴性结石、逆行造影困难、碘过敏者更具有价值。 相似文献
40.
Adenoma with gastric differentiation (so-called pyloric gland adenoma) in a heterotopic gastric corpus mucosa in the rectum 总被引:1,自引:0,他引:1
Vieth M Kushima R de Jonge JP Borchard F Oellig F Stolte M 《Virchows Archiv : an international journal of pathology》2005,446(5):542-545
In a 46-year-old man, a pedunculated rectal polyp measuring 3.0×3.0×2.0 cm was diagnosed histologically as a pyloric gland-type adenoma arising in heterotopic gastric corpus mucosa. The luminal site was covered by glands of the gastric foveolar type, displaying focal marked proliferation interpreted as low-grade intraepithelial neoplasia. A bidirectional gastric differentiation was found: most lower glandular structures showed positivity for the deep gastric mucin core protein Muc 6 and superficial positivity for gastric foveolar epithelium mucin core protein Muc 5AC. Pyloric gland adenoma has so far been described in one larger series only and a few case reports of the stomach, gallbladder, pancreatic duct and within heterotopic gastric corpus mucosa of the duodenal bulb. The present case report is the first case of a pyloric gland-type adenoma within a gastric corpus heterotopia of the rectal mucosa. 相似文献