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991.
Nonsyndromic cleft lip with or without cleft palate (CLP) is a common craniofacial anomaly, the etiology of which is not known. Population studies have shown that a large proportion of cases occur sporadically. Recently, segregation analyses applied to CLP families have demonstrated that an autosomal dominant/codominant gene(s) may cause clefting in cases. Associations of autosomal dominant CLP and nonsyndromic cleft palate (CP) with HLA and F13A genes on chromosome 6p have been suggested previously. Linkage to these two areas on chromosome 6p were tested in 12 autosomal dominant families with CLP. With a LOD score of -2 or less for exclusion, no evidence of linkage was found to four chromosome 6p markers. Multipoint analysis showed no evidence of a clefting locus in this region spanning 54 cM on chromosome 6p in these CLP families.  相似文献   
992.
Otorrhea occurs after the insertion of tympanostomy tubes in as many as 50% of ears. Although topical antibiotic solutions minimize otorrhea in the immediate postoperative period, recurrent otorrhea is sometimes a clinical problem. The antimicrobial effects of silver oxide when impregnated into a tympanostomy tube may decrease the incidence of recurrent otorrhea. This study demonstrates that silver oxide-impregnated silicone elastomer is well tolerated within the middle ear of gerbils when implanted for 1 year, and the tissue reaction is no more than silicon elastomer without silver oxide. When applied directly to the round window of guinea pigs, there was no evidence of ototoxicity of silver oxide as measured by electrocochleography (N-1 thresholds) and cytocochleography (hair cell counts). These animal studies indicate that silver oxide-impregnated silicone elastomeric tympanostomy tubes may be used safely in clinical trials to determine efficacy.  相似文献   
993.
A box model for the dispersion of radionuclides in the marine environment covering the Arctic Ocean and the North Atlantic Ocean has been constructed. Collective doses from ingestion pathways have been calculated from unit releases of the radionuclides 3H, 60Co, 63Ni, 90Sr, 129I, 137Cs, 239Pu and 241Am into a fjord on the east coast of NovayaZemlya. The results show that doses for the shorter-lived radionuclides (e.g. 137Cs) are derived mainly from seafood production in the Barents Sea. Doses from the longer-lived radionuclides (e.g. 239Pu) are delivered through marine produce further away from the Arctic Ocean. Collective doses were calculated for two release scenarios, both of which are based on information of the dumping of radioactive waste in the Barents and Kara Seas by the former Soviet Union and on preliminary information from the International Arctic Sea Assessment Programme. A worst-case scenario was assumed according to which all radionuclides in liquid and solid radioactive waste were available for dispersion in the marine environment at the time of dumping. Release of radionuclides from spent nuclear fuel was assumed to take place by direct corrosion of the fuel ignoring the barriers that prevent direct contact between the fuel and the seawater. The second scenario selected assumed that releases of radionuclides from spent nuclear fuel do not occur until after failure of the protective barriers. All other liquid and solid radioactive waste was assumed to be available for dispersion at the time of discharge in both scenarios. The estimated collective dose for the worst-case scenario was about 9 manSv and that for the second scenario was about 3 manSv. In both cases, 137Cs is the radionuclide predicted to dominate the collective doses as well as the peak collective dose rates.  相似文献   
994.
995.
Adolescent cancer is uncommon and presents an exceptional stress for the young patient and their parents. The emotional needs of adolescents with cancer are a major factor in the recommendation for the establishment of adolescent cancer units in major cancer centres in the U.K. However, there have been no prospective, longitudinal studies assessing the psychological impact of a diagnosis of cancer on the adolescent patient and their family. In 1994 we began a longitudinal study of the emotional impact of the diagnosis of cancer in patients and their families presenting to an adolescent cancer unit and of the coping strategies they employ. This first report presents the results of the study at the time of diagnosis in 42 adolescents, 34 mothers and 27 fathers. The Beck Depression Inventory (BDI) was used to assess depression and anxiety levels were measured using Spielberger's State Trait Anxiety Inventory (STAI). Adolescents and their parents completed the questionnaires on first admission to the adolescent cancer unit. The median time since cancer diagnosis was approximately 3 weeks. To provide normative data for the U.K. adolescent population, control values were obtained from 173 pupils of the same age and background. The results showed that, contrary to expectation, adolescents with cancer were no more anxious or depressed than the control adolescent population. Nevertheless, a substantial minority of patients and controls had elevated anxiety or depression scores. Girls were significantly more anxious (P = 0.011) and depressed (P < 0.0001) than boys. Mothers were the most anxious family members and were significantly more anxious than fathers (P = 0.038). Parental anxiety scores, especially mothers, were much higher than reported norms. There was no significant difference between mothers' and fathers' depression scores. Although at the time of diagnosis adolescent cancer patients are not more anxious or depressed than their healthy peers, many adolescents without cancer are anxious or depressed. Staff on adolescent cancer units should therefore be aware of the frequency of emotional disturbance in this population. Mothers are the most anxious family members. Although the findings are relatively reassuring at the time of diagnosis, follow-up data from this cohort will show whether anxiety and depression change with treatment involving intensive chemotherapy, surgery and radiotherapy and will indicate the coping strategies which patients and their families adopt in dealing with both the disease and its treatment.  相似文献   
996.
BACKGROUND: Activation of coagulation and fibrinolysis occurs as a stress response to surgery and may predispose the patient to thromboembolic complications. Other components of the surgical stress response (cytokine release, neurohumoral response, etc.) have been shown to differ between laparoscopic and open cholecystectomy, and the aim of this study was to investigate the effects of laparoscopic and open surgery on the coagulation and fibrinolytic pathways. METHODS: Fourteen patients undergoing laparoscopic cholecystectomy and 12 patients undergoing open cholecystectomy had blood taken in the perioperative period for fibrinopeptide A (FPA) prothrombin fragment F1.2, antithrombin 3, tissue plasminogen activator (tPA) and its fast-acting inhibitor plasminogen activator inhibitor-1 (PAI-1 antigen and activity), and the euglobulin clot lysis time (ECLT). RESULTS: The only significant differences between the two groups occurred 6 h after surgery when the ECLT was longer (p < 0.005; Mann Whitney), and PAI-1 antigen and activity were higher (p < 0.01 and p < 0.001, respectively; Mann Whitney) after open cholecystectomy than laparoscopic cholecystectomy. CONCLUSIONS: Other changes in fibrinolysis and coagulation were similar for open and laparoscopic cholecystectomy. With respect to hemostasis, laparoscopic cholecystectomy does not increase the risk of thromboembolic complications compared to the conventional procedure.  相似文献   
997.
998.
Galanin (GAL) and neuropeptide Y (NPY) have been shown to play important roles in the regulation of pituitary hormone secretion, as well as ingestive and sexual behaviors, by acting within the hypothalamus. While the mechanism of action of these regulatory peptides is under intensive investigation, less attention has been paid to the possible interaction between them in influencing these central regulatory processes. Because NPY and GAL augment pituitary gonadotropin release, the present study was undertaken to evaluate the nature of morphological and functional relationships between these excitatory hypothalamic peptidergic systems. Double immunolabeling for NPY and GAL was carried out on vibratome sections taken from the hypothalamus of colchicine-pretreated female rats. Avidinbiotin peroxidase technique and a dark blue diaminobenzidine reaction was used to visualize NPY profiles, while the GAL neurons were labeled with a light brown diaminobenzidine reaction using either the avidin-biotin peroxidase or the peroxidase antiperoxidase technique. Light microscopic examination of the immunostained material showed that in the arcuate nucleus, paraventricular nucleus, supraoptic nucleus, anterior hypothalamus, and medial preoptic area, an abundant network of NPY-immunoreactive axons surrounded GAL-immunostained cells. Numerous dark blue NPY-containing putative boutons were observed in close proximity to GAL-immunolabeled cell bodies and dendrites. Correlated light and electron microscopic examination revealed that most of the immunoreactive NPY axon terminals established synaptic connections with GAL-expressing cells. Synaptic connections were most frequently found in the medial preoptic area and in the magnocellular region of the paraventricular nucleus and arcuate nucleus. Fewer connections were observed in the supraoptic nucleus. These morphological observations demonstrate the existence of a strong NPY input to hypothalamic GAL neurons, thereby suggesting a modulatory role for NPY in monitoring GAL release. To evaluate the functional relevance of this anatomical relationship, the effects of intraventricular injection of a GAL receptor antagonist, galantide, were examined on NPY-induced LH release in ovarian steroid-primed ovariectomized rats. As expected, intraventricular injection of NPY readily stimulated LH release. Although, while on its own, galantide was ineffective in altering basal LH release, it markedly attenuated the NPY-induced LH response, thereby suggesting that GAL released in response to NPY administration may, in part, mediate the excitatory effects of NPY. These experimental results, taken together with the morphological observations, document the involvement of an NPY --> GAL signaling modality in the release of gonadotropins and, likewise, raise the possibility of a similar signaling process in the release of other pituitary hormones and elicitation of behavioral effects attributed to NPY and GAL.  相似文献   
999.
1000.
An analysis of 125 patients with closed head injury was completed in order to identify the risk factors involved in the development of early pneumonia. Pneumonia was diagnosed in 60% of the patients. Early pneumonia developed in 47.8% of the patients. Brain-injured patients who developed early pneumonia were found to have a lower Glasgow Coma Scale (GCS) score. Early pneumonia was found more often in patients with swallowing disorders and evidence of aspiration. Patients who had been intubated in the field were found to be at greater risk for the development of early pneumonia than those intubated in the hospital. Patients with early pneumonia had prolonged intubation times, intensive care unit stays, and hospital stays. This study suggests that a GCS score less than 5, evidence for swallowing disorders and aspiration, and field intubation are risk factors for early pneumonia in the brain-injured patient.  相似文献   
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