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91.
Anatomy of the guinea pig temporal bone.   总被引:6,自引:0,他引:6  
The middle ear of guinea pigs has long been used for experimental studies, but no detailed information about its temporal bone anatomy is available. In 18 adult guinea pigs, the temporal bone, eustachian tube, and inner ear anatomy, in addition to the anatomy of the middle ear, were investigated under the dissection microscope. In addition to properties of the eardrum, ossicles, air cell system, and cochlea previously described, the appearance of Huschke's foramen and the crista stapedis in an adult guinea pig ear, the structure of the eustachian tube, the architecture of the internal auditory canal, and the communication of the mastoid cells with the tympanic bulla are described. Differences and similarities among guinea pigs, other experimental animals, and humans are discussed to show the advantages and disadvantages of the guinea pig ear for experimentation.  相似文献   
92.

Background

Extra-adrenal paragangliomas (PGLs) are infrequent, benign, and neuroendocrine tumors arising from chromaffin cells of the autonomic nervous system. Most PGLs are sporadic, but up to 32% are associated with inherited syndromes such as neurofibromatosis type 1, von Hippel-Lindau disease, and familial PGL. Although most PGLs develop above the umbilicus, they have been reported in the genitourinary (GU) tract. Owing to the paucity of literature on the rates of GU PGL, the objective of our study is to describe the demographic, pathologic, and clinical characteristics of GU PGL, and compare them to non-GU sites of PGL using the surveillance, epidemiology, and end results (SEER) database.

Methods

The SEER 18 database was used to identify all cases of PGL from 2000 to 2012. Demographic, pathologic, and clinical characteristics were described using chi-square and t-test for categorical and continuous variables, respectively. The Kaplan-Meier method was used to compare overall survival (OS) between GU and non-GU PGL. Statistical significance was defined as P<0.05. All analyses were performed using excel and SAS/Stat version 9.4.

Results

A total of 299 cases of PGL were retrieved from SEER, and 20 (6.7%) of the total PGL arose from the GU tract. The mean age at diagnosis was higher in non-GU than GU PGL (50.4±17.2 vs. 40.8±15.6, P = 0.026). Furthermore, 75% of GU PGLs developed in the bladder, followed by the kidneys/renal pelvis, and spermatic cord (20%). Non-GU PGL developed most frequently within the endocrine system (43%). PGL, overall, was more common in men than in women, and it was more common in whites than all other races. Although 55.5% of GU PGLs were organ confined, only 22.2% of non-GU PGLs were localized at diagnosis. All cases of PGL were treated with surgery. There were 2 cause-specific deaths in the GU PGL groups between 2000 and 2012. The 5-year OS was 93.3% for GU PGL vs. 65.5% in non-GU PGL (P = 0.062).

Conclusions

GU PGL remains rare with low incidence (6.7% of all PGL cases) in the US population between 2000 and 2012. Bladder PGL represents just 5% of all PGL. Moreover, GU PGL had better OS compared to PGL developing outside of the GU tract although the P-value only approached statistical significance. The bladder represents the most common site of involvement, and surgery is the mainstay of treatment for GU PGL. Clearer prognostic factors, including tumor grade and stage, are needed to better elucidate PGL management in the future; thus, pooled studies from various institutions with detailed clinical information are needed to delineate these prognostic factors.  相似文献   
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95.
A new animal model has been developed to study early thrombosis in small calibre vascular prostheses. It consists of an eETFE graft 2 cm long and of 3mm internal diameter inserted into a rabbit abdominal aorta in which the distal run-off is reduced by narrowing both common iliac arteries using clips with a standard gap. Scanning electron microscopy and gamma imaging of the graft using labelled autologous platelets showed that, as in the human, platelets played a primary role in the model graft thrombosis. This model was used to study the effect of haemodulution on early graft patency. Moderate normovolaemic haemodilution dramatically improved the early patency rate.  相似文献   
96.
INTRODUCTION: It is considered that many factors may play a role in urolithiasis. Experimental and clinical studies have shown that zinc has an inhibitory effect on urolithiasis. MATERIALS AND METHODS: In this study, urinary zinc and copper were measured in 27 healthy controls and 30 calcium oxalate stone formers. RESULTS: Urinary zinc excretion was significantly higher (p < 0.001) in stone formers than healthy controls (2,575 +/- 274 and 960 +/- 80 mg/day, respectively). There was no significant difference in urinary copper excretion between healthy controls and stone formers (32.3 +/- 3.5 and 33.3 +/- 3.2 microg/day, respectively). CONCLUSIONS: According to our results, the potent inhibitory effect of urinary zinc excretion on urolithiasis could be reviewed.  相似文献   
97.
The purpose was to evaluate the value of radiology to distinguish between symptomatic and asymptomatic flexible flatfeet in young male adults. Among young male army recruits, 56 feet of 28 recruits were diagnosed as otherwise normal, flexible flatfoot with invisible longitudinal arch on stance and either symptomatic or asymptomatic unilaterally or bilaterally. The talus-first metatarsal and calcaneal pitch angles were measured on weight-bearing lateral radiographs, and the results were evaluated statistically. The talus-first metatarsal angle showed statistical significance in both non-parametric and logistic regression tests, but the calcaneal pitch angle showed statistical significance only in non-parametric test between symptomatic and asymptomatic flatfoot groups. Although the single gender and number of samples limit the applicability of our study, these results caused us to make an interpretation that increased talus-first metatarsal angle might be an important risk factor of being symptomatic in otherwise normal flexible flatfoot.  相似文献   
98.
99.
Ginkgo biloba inhibits bleomycin-induced lung fibrosis in rats.   总被引:1,自引:0,他引:1  
Oxidative stress has been implicated in the pathogenesis of bleomycin-induced lung fibrosis and many antioxidant agents have been studied for prevention and treatment of the disease in animals and humans. We therefore examined whether Ginkgo biloba (Gb), a flavonoid-rich antioxidant, inhibits bleomycin-induced lung fibrosis in rats. Male Sprague-Dawley rats were given a single dose of bleomycin (2.5 mg/kg, intratracheally) in pulmonary fibrosis groups and saline in controls. First dose of Gb was given a day before the bleomycin injection and continued until sacrifice. At day 14, fibrotic changes in lung were estimated to occur by Aschoft's criteria and lung hydroxyproline content. Bleomycin challenge provoked severe pulmonary fibrosis with marked increase in hydroxyproline content of lung tissue and typical histological findings, which is prevented by Gb. Hydroxyproline level was significantly higher (13.51+/-0.87 mg/g dried tissue) in bleomycin treated rats than controls (9.2+/-1.33), and its level was remained to the control levels (7.38+/-0.76) in rats treated with prophylactic Gb. On the other hand, bleomycin injection significantly reduced activities of glutathione peroxidase, superoxide dismutase and catalase in lung tissue which is prevented by Gb. Also, bleomycin injection resulted in a marked increase of malondialdehyde and nitrite level which is attenuated by Gb. The data suggest that Gb has a potent antioxidant activity in the model of bleomycin-induced lung fibrosis in rats, and therefore has a potent antifibrotic activity against bleomycin-induced lung fibrosis model in rats.  相似文献   
100.
Aim: To evaluate the impact of extracellular and intracellular Ca2+ on contractions induced by ethanol in smooth muscle. Methods: Longitudinal smooth muscle strips were prepared from the gastric fundi of mice. The contractions of smooth muscle strips were recorded with an isometric force displacement transducer. Results: Ethanol (164 mmol/L) produced reproducible contractions in isolated gastric fundal strips of mice. Although lidocaine (50 and 100 μmol/L), a local anesthetic agent, and hexamethonium (100 and 500 μmol/L), a ganglionic blocking agent, failed to affect these contractions, verapamil (1-50 μmol/L) and nifedipine (1-50 pmol/L), selective blockers of L-type Ca2+ channels, significantly inhibited the contractile responses of ethanol. Using a Ca2+-free medium nearly eliminated these contractions in the same tissue. Ryanodine (1-50 μmol/L) and ruthenium red (10-100 pmol/L), selective blockers of intracellular Ca2+ channels/ryanodine receptors; cyclopiazonic acid (CPA; 1-10 μmol/L), a selective inhibitor of sarcoplasmic reticulum (SR) Ca2+-ATPase; and caffeine (0.5-5 mmol/L), a depleting agent of intracellular Ca2+ stores, significantly inhibited the contractile responses induced by ethanol. In addition, the com- bination of caffeine (5 mmol/L) plus CPA (10 μmol/L), and ryanodine (10 μmol/L) plus CPA (10 μmol/L), caused further inhibition of contractions in response to ethanol. This inhibition was significantly different from those associated with caffeine, ryanodine or CPA. Furthermore the combination of caffeine (5 mmol/L), ryanodine (10 μmol/L) and CPA(IO pmol/L) eliminated the contractions induced by ethanol in isolated gastric fundal strips of mice. Conclusion: Both extracellular and intracellular Ca2+ may have important roles in regulating contractions induced by ethanol in the mouse gastric fundus.  相似文献   
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