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91.
M I Chuah  D R Zheng 《Neuroscience》1987,23(1):363-370
Light microscopic observations indicated that cellular differentiation of the primary olfactory pathway in human fetuses was relatively advanced by the end of the first trimester. However, immunohistochemical staining showed that olfactory marker protein was present in the receptor cells only at about 28 weeks post-conception. At about 32 weeks, modest amounts of the protein could be found in the peripheral olfactory nerve layer and a few glomeruli, with increased staining observed in subsequent weeks. The results show conclusively that human fetal olfactory neurons synthesize olfactory marker protein during the later half of gestation.  相似文献   
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93.
The maturation of olfactory receptor cells is facilitated by the presence of their target tissue, the olfactory bulb. Organ cultures of embryonic rat olfactory mucosa (OM) maintained in the presence of the presumptive olfactory bulb (POB) had a significantly higher (1.6 X) density of ciliated dendritic knobs than those without the POB. No significant difference was found in the density of non-ciliated dendritic knobs and total knob density in these two groups of cultures. A control group of explants in which the OM and POB had been separated and recombined also showed an increased ciliated dendritic knob density. The area of the olfactory epithelium was the same whether or not the POB was present. In addition, scanning electron microscopy observations revealed a high degree of heterogeneity in the surface morphology of the olfactory epithelium.  相似文献   
94.
Hemangioma of the nasal vault: MR and CT features   总被引:1,自引:0,他引:1  
W P Dillon  P M Som  W Rosenau 《Radiology》1991,180(3):761-765
Six patients with a history of epistaxis (five patients) or nasal obstruction (one patient) were found to have a capillary hemangioma of the nasal vault that involved one or more nasal turbinates. Four patients underwent computed tomographic (CT) examination; two of these also underwent magnetic resonance (MR) imaging. Four others underwent only MR imaging. At CT and MR, all of the lesions were well circumscribed and intensely enhancing, with contralateral deviation of the nasal septum. Remodeling of the surrounding bone was present in three patients. On T1-weighted MR images, the masses were intermediate in signal intensity. Varying degrees of T2 shortening were shown on T2-weighted MR images, with an appearance that suggested the presence of blood products surrounding an inner matrix of higher-signal-intensity tumor. Intense enhancement at CT and MR assisted differentiation of tumor from retained sinonasal secretions. In two patients, external carotid arteriography revealed small foci of pooling contrast material; in one of these patients, arteriovenous shunting was also present. Pathologic examination in all patients demonstrated capillary hemangiomas with varying degrees of fibrosis and hemosiderin deposition.  相似文献   
95.
The Asia–Pacific Working Group on Inflammatory Bowel Disease was established in Cebu, Philippines, under the auspices of the Asia–Pacific Association of Gastroenterology with the goal of improving inflammatory bowel disease care in Asia. This consensus is carried out in collaboration with Asian Organization for Crohn's and Colitis. With biologic agents and biosimilars becoming more established, it is necessary to conduct a review on existing literature and establish a consensus on when and how to introduce biologic agents and biosimilars in conjunction with conventional treatments for ulcerative colitis and Crohn's disease in Asia. These statements also address how pharmacogenetics influences the treatments of ulcerative colitis and Crohn's disease and provides guidance on response monitoring and strategies to restore loss of response. Finally, the review includes statements on how to manage treatment alongside possible hepatitis B and tuberculosis infections, both common in Asia. These statements have been prepared and voted upon by members of inflammatory bowel disease workgroup employing the modified Delphi process. These statements do not intend to be all‐encompassing, and future revisions are likely as new data continue to emerge.  相似文献   
96.
Recent advances in the treatment of achalasia include the use of high-resolution manometry to predict the outcome of patients and the introduction of peroral endoscopic myotomy(POEM).The first multicenter randomized,controlled,2-year follow-up study conducted by the European Achalasia Trial group indicated that laparoscopic Heller myotomy(LHM)was not superior to pneumatic dilations(PD).Publications on the long-term success of laparoscopic surgery continue to emerge.In addition,laparoscopic single-site surgery is applicable to advanced laparoscopic operations such as LHM and anterior fundoplication.The optimal treatment option is an ongoing matter of debate.In this review,we provide an update of the current progress in the treatment of esophageal achalasia.Unless new conclusive data prove otherwise,LHM is considered the most durable treatment for achalasia at the expense of increased reflux-associated complications.However,PD is the first choice for non-surgical treatment and is more costeffective.Repeated PD according to an"on-demand"strategy based on symptom recurrence can achieve long-term remission.Decision making should be based on clinical evidence that identifies a subcategory of patients who would benefit from specific treatment options.POEM has shown promise but its long-term efficacy and safety need to be assessed further.  相似文献   
97.
98.
A 49-year-old alcoholic developed hepatic encephalopathy following dietary supplementation with branched-chain amino acid (BCAA). He became lucid within 24 hours of withdrawing BCAA. Subsequent re-challenge with BCAA again precipitated hepatic encephalopathy. In future, BCAA should be prescribed with care.  相似文献   
99.

Background

A retrospective assessment of contrast enhanced computed tomography (CECT) scan findings in histopathologically proven cases of carcinoma of the gallbladder (GB) was performed to review its role in diagnosis, staging and assessment of surgical resectability.

Methods

All the patients had been subjected to a standardised abdominal helical computed tomography scan. Orally administered iodinated contrast was used for opacification of bowel and dynamic intravenous injection of non-ionic iodinated contrast for studying the lesional enhancement and vascular structures.

Results

The presence of focal or diffuse mass lesions in the gallbladder fossa, infiltration of a liver and second part of duodenum were the most reliable diagnostic features in carcinoma gallbladder. Regional spread was better delineated on CT scan as compared with ultrasonography.

Conclusion

CT scan is an effective method for evaluating, characterizing and detecting the spread of GB carcinomas.Key Words: Gall Bladder, Carcinoma, Computed Tomography  相似文献   
100.
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