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991.
OBJECTIVE: Recent studies have suggested that inositol triphosphate is transmitted through the gap junction of adjacent epithelial cells and communicates the intracellular calcium wave that controls the beating of cilia. Therefore, gap junction-mediated intercellular communication may modulate the metachronal ciliary beating of respiratory mucosa. MATERIAL AND METHODS: The expression and function of gap junctions were evaluated in nasal mucosa using immunofluorescent staining, Western blotting and Lucifer Yellow dye coupling in both whole nasal mucosa and cultured nasal epithelial cells. RESULTS: Among connexins (Cxs) 26, 32 and 43, only Cx43 was found in the nasal mucosa, in both the epithelial cells and submucosa tissue. Using Western blotting, Cx43 protein was found in protein extracts of both whole mucosa and cultured epithelial cells. The Cx43 protein content increased twofold between the 3rd and 6th days of culture. Lucifer Yellow dye, microinjected into single cultured epithelial cells, had spread to the adjacent cells. CONCLUSION: Cx43 is present in nasal mucosa. The expression of Cx43 on epithelial cells increases after culture. The dye-coupling study in epithelial cells indicated that the signal may be transmitted to neighboring cells via a gap junction composed of Cx43. Thus, Cx43 may be involved in the regulation of metachronal ciliary beating in ciliated epithelial cells and growth or differentiation in nasal tissue.  相似文献   
992.
The chronic effects of unilateral peripheral vestibular loss (UPVL) are influenced by vestibular compensation. This study documents the balance-related symptoms and quantitative vestibular laboratory testing of 20 patients with surgically confirmed UPVL. Included are measures of the semicircular canal-ocular reflex, the otolith-ocular reflex, and both static and dynamic semicircular canal-otolith-interaction. This study differs from previous studies of patients with UPVL in that a large number of patients with surgically confirmed lesions were tested with three types of off-vertical axis rotation, several of the patients had anatomically preserved superior vestibular nerves, and self-perceived level of disability related to dizziness and imbalance were available. Results confirmed previously reported changes in the vestibulo-ocular reflex of patients with UPVL. Also, there was no apparent effect of anatomically preserving the superior vestibular nerve during surgical resection of vestibular schwannomas based on either subjective or objective measures of vestibular dysfunction. Further, there were no apparent correlations between subjective measures of dizziness and imbalance and objective measures of vestibulo-ocular function. These results have clinical implications for the management of patients with unilateral vestibular loss and provide insights into the process of vestibular compensation especially with respect to the otolith-ocular reflex.  相似文献   
993.
We report on the use of penile tumescence assessment to diagnose a paraphiliac client who was in denial about his problem. An 18-year-old male was accused of sexually assaulting a 4-year-old girl using physical restraint and vaginal penetration with a finger. During a psychiatric evaluation requested by the court, a comprehensive psychosexual assessment revealed that the subject was in denial about clarification of the paraphiliac experience. Penile tumescence under distinct visual stimulus was evaluated with electrobioimpedence volumetric assessment using child and adult female pictures in separate time frames. Both types of stimuli evoked arousal responses. However, child female stimuli demonstrated stronger responses than did adult female ones. Deviant sexual interest in children as well as a diagnosis of pedophilia was implied. Paraphiliac clients tend to be in denial toward psychosexual assessment which limits the interpretation of its results. Penile tumescence assessment may be more reliable than psychosexual assessment alone for detecting and diagnosing paraphilia. Further study is warranted in order to aid in more accurate diagnoses of paraphilia.  相似文献   
994.
995.
Hypopharyngeal hemangiomas are uncommon neoplasms that can cause dysphagia, recurrent bleeding, and airway obstruction. These lesions are a therapeutic challenge, and surgical resection is the mainstay of therapy. The goal of therapy is directed at control of the tumor and relief of symptoms rather than total eradication of the lesion. Laser therapy is a very useful adjunct in the management of these vascular neoplasms. The neodymium: yttrium-aluminum-garnet laser (Nd:YAG laser) functions at a wavelength that provides deep thermal coagulation. This allows its use for these vascular lesions. With laser surgery, hemorrhage is the most frequent and dangerous complication, and its control is extremely important. Ligation and suture remain the traditional methods of hemostasis in most surgical situations. However, on certain occasions problems arise, particularly with large oozing surfaces or when surgical access is poor. Topical hemostatic agents are widely used in a variety of surgical procedures to successfully solve such problems. Microfibrillar collagen (Avitene) is one of the absorbable, topical, hemostatic agents, and is used effectively to control bleeding in many surgical situations. Since we began to use microfibrillar collagen (AviteneTM, MedchemProduct, Inc., Woburn, MA01801) to stop the massive oozing of the laser-induced surgical wound, no episodes of bleeding had ever occurred. It is concluded that Avitene is an effective agent for maintaining hemostasis in many surgical procedures, and we consider it a good remedy for management of laser-induced bleeding complications.  相似文献   
996.
The diagnosis of impacted foreign body in the colon is usually delayed until the complications such as perforation or abscess formation occur. Here we describe a patient who presented with diffuse abdominal pain due to the impaction of a dental prosthesis in the hepatic flexure of the colon. The dental prosthesis, which was inadvertently swallowed, was successfully removed under colonoscopy. Unexplained abdominal pain should alert the clinician to the possibility of foreign body ingestion and further therapeutic colonoscopy may replace or lessen the need for surgical procedures to extract foreign bodies from the colon.  相似文献   
997.
A premature infant experienced respiratory distress due to chylothorax. Contrast-enhanced chest computed tomography showed superior vena cava (SVC) obstruction with collaterals, and surgery confirmed an obstruction of the SVC by intravascular fibrotic tissue and thrombi caused by placement of a central venous catheter. The respiratory distress improved after surgical intervention. In the differential diagnosis of acute respiratory distress, it is necessary to consider catheter-related chylothorax and SVC syndrome when a previously stable patient has an acute change in cardiopulmonary status, regardless of the duration of catheter use. Although often considered safe and easy, central venous catheter placement may result in complications. Using appropriate catheters and choosing proper insertion sites can minimize these events. Early diagnosis and treatment can be life-saving should complications occur.  相似文献   
998.
Screening for metals in urine is important because toxic levels of these elements are linked to disease. In the current study, the authors used differential pulse stripping voltammetry on a hanging mercury drop electrode for the simultaneous determination of cadmium, cobalt, lead, and nickel in the urine of 63 production and 63 quality control workers in a steel production plant, along with 63 matched normal controls. Urinary sampling is a noninvasive procedure, and in this study participants had good compliance. Metal levels for both the production and quality control workers were significantly higher than for controls. The results reveal the need for immediate improvements in workplace ventilation and industrial hygiene practices for this cohort.  相似文献   
999.
1000.
In order to determine the effect of perinatal polychlorinated biphenyls and dibenzofurans (PCBs/PCDFs) exposure on neonatal and childhood teeth in Yucheng children, we carried out complete dental examinations on 73 Yucheng children born to mothers who ingested high levels of PCBs/PCDFs and 75 matched controls, aged 7-11 years, in 1992. Ten of 73 (10%) exposed children were reported to have borne teeth during the neonatal period, while none of the controls did. The exposed group also had a significantly higher percentage of teeth with congenitally missing tooth germ compared to the controls (29 vs 2.7%) or rotation (19 vs 2.7%). The percentages of developmental defects increased significantly with increasing maternal serum PCB levels, childhood PCB and PCDF levels, and the duration of breast feeding. The maternal PCB level clearly played a more important role in an increased risk of neonatal teeth and developmental defects. The defects were apparent from the lowest tertile, with a total PCB level of <10 ppb in maternal serum measured nearest to childbirth. The number of permanent teeth tended to be less in exposed children than in the control group from the age of 11 years onwards. Our present study has demonstrated for the first time a dose-response relationship between perinatal PCBs/PCDFs exposure and dental defects.  相似文献   
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