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81.
82.
The soft tissue profiles of 85 16-18 year old children with unilateral clefts of the lip, alveolus, and palate treated according to four different regimes were studied using lateral skull radiographs. Regimes that included secondary bone grafting to the alveolus in the mixed dentition gave better convexity of the soft tissue profile (excluding the nose) and better soft tissue sagittal jaw relationships compared with treatment regimens that included primary bone grafting. The soft tissue profile in regimes that excluded bone grafting was almost as favourable as those in regimes in which bone grafting was done during the mixed dentition.  相似文献   
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Study Type – Therapy (case series) Level of Evidence 4 What’s known on the subject? and What does the study add? The indications and timing of native nephrectomy in patients with autosomal dominant polycystic kidney disease (ADPKD) is controversial, especially for those undergoing renal transplantation. Post‐transplant unilateral native nephrectomy appears to be the preferred intervention compared to pre‐transplant native nephrectomy. There seems to be substantial additive risk to bilateral over unilateral nephrectomy, especially prior to transplantation. Pre‐transplant native nephrectomy should only be carried out when there are clear indications such as massive size preventing allograft placement, severe pain, early satiety, recurrent bleeding and infections, or suspected malignancy.

OBJECTIVE

To analyse indications, timing and outcomes of native nephrectomy in autosomal dominant polycystic kidney disease (ADPKD) patients listed for kidney transplantation.

PATIENTS AND METHODS

A retrospective analysis of all ADPKD patients who had a native nephrectomy prior to or following transplantation between January 2003 and December 2009 at a single centre, including those undergoing the sandwich technique (removal of the most severely affected native kidney prior to transplantation, and the other afterwards), was undertaken.

RESULTS

There were 35 individuals in our cohort (M : F = 16 : 19), with a median age of 51.5 years (range 43–65). Twenty patients were in the pre‐transplant nephrectomy group, 12 in the post‐transplant group, and three underwent the sandwich technique. Indications for nephrectomy varied but were most commonly pain/discomfort, space for transplantation, ongoing haematuria, recurrent infections, and gastrointestinal pressure symptoms (early satiety). Seven individuals in the pre‐transplant group and three in the post‐transplant group required critical care admission after nephrectomy. Transient renal graft dysfunction occurred in two post‐transplant bilateral nephrectomy patients. Two patients in the bilateral nephrectomy pre‐transplant group and one in the bilateral nephrectomy post‐transplant group died in the immediate post‐operative period. No complications were noted in the sandwich technique group.

CONCLUSION

Native nephrectomy in ADPKD is a major undertaking associated with significant morbidity especially in the pre‐transplant group. Post‐transplant unilateral nephrectomy appears to be the safest approach with fewest complications.  相似文献   
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The distribution of nitric oxide producing neurones in the medulla oblongata of the cat was investigated using nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase histochemistry, and nitric oxide synthase (NOS) immunohistochemistry. The pattern of staining obtained with both methods was found to be similar. Strongly diaphorase and NOS reactive neurones were present in the paramedian and lateral tegmental fields, including the regions occupied by the Al/C1 catecholamine cell groups, the nucleus ambiguus and lateral reticular nucleus, and in a number of sensory nuclei including the nucleus of the tractus solitarius and the dorsal column nuclei. The extent of co-localization of NADPH-diaphorase with a number of neuropeptides and neurotransmitters was investigated by combining NADPH-diaphorase histochemistry with immunocytochernisty for neuropeptide Y, somatostatin, glutamate, cholecystokinin and tyrosine hydroxylase. NADPH-diaphorase reaction product was observed in neurones immunoreactive for glutamate and somatostatin. These double-labelled cells were found in the paramedian region, lateral reticular field, the nucleus prepositus hypoglossi and in the rostral nucleus of the tractus solitarius. In the rostral ventrolateral medulla NADPH-diaphorase/somatostatin immunoreactive cells were found in the paragigantocellular nucleus. NADPHdiaphorase/glutamate immunoreactive cells overlapped the nucleus ambiguus, the lateral reticular nucleus and the A1/C1 catecholaminergic cell groups. In addition, a few NADPH-diaphorase/glutamate immunoreactive cells were found in the paraolivary area and gigantocellular tegmental field, in the external cuneate and infratrigerninal nuclei. The functional implications of the co-localization of nitric oxide with these neurotransmitters in areas of the medulla concerned with cardiovascular regulation is discussed.  相似文献   
88.
To reveal neurones in the cat medulla oblongata involved in carotid baroreceptor/chemoreceptor reflexes, the distribution of c-Fos oncoprotein immunoreactivity was studied following electrical stimulation of the right carotid sinus nerve. The neurochemistry of the activated neurones was investigated using antisera to tyrosine hydroxylase, neuropeptide Y, somatostatin, and glutamate. Nitric oxide containing neurones were identified using antiserum to nitric oxide synthase (NOS) and by the histochemical localization of nicotinamide adenine dinucleotide phosphate (NADPH)-diaphorase. Following sinus nerve stimulation numerous c-Fos-IR cells were detected both ipsilaterally and contralaterally in the nucleus tractus solitarii, the area postrema and throughout the ventrolateral medulla. Dual labelling studies revealed that 3.3% of c-Fos- immunoreactive cells in the nucleus tractus solitarii were also immunoreactive for tyrosine hydroxylase. The double labelled cells were scattered within the medial and ventrolateral subnuclei, predominantly rostral to obex. A higher proportion (10.3%) of c-Fos-IR cells in the ventrolateral medulla also showed tyrosine hydroxylase immunoreactivity. Caudal to obex, these were scattered in the reticular formation between the spinal trigeminal nucleus and the lateral reticular nucleus, while more rostrally they were found within the lateral reticular nucleus, the nucleus ambiguus and the lateral tegmental field. Cells expressing c-fos and reactive for glutamate, neuropeptide Y or NADPH-diaphorase (or NOS) were only rarely seen, and co-localization of c-Fos and somatostatin immunoreactivities was not seen. These results suggest that of the neurones forming pathways within the medulla activated on carotid sinus nerve stimulation, presumably mediating baro- and chemoreceptor reflexes, relatively few utilize catecholamines, glutamate, neuropeptide Y or nitric oxide as their transmitter substance.  相似文献   
89.
OBJECTIVES: To investigate the relationship of specific nutrients and food items with oral precancerous lesions among tobacco users.
DESIGN: A population-based case-control study. SETTING: Villages in Palitana taluk of Bhavnagar district, Gujarat, India.
SUBJECTS AND METHODS: An interviewer-administered food frequency questionnaire, developed and validated for this population, was used to estimate nutrient intake in blinded, house-to-house interviews. Among 5018 male tobacco users, 318 were diagnosed as cases. An equal number of controls matched on age (±5 years), sex, village, and use of tobacco were selected.
MAIN OUTCOME MEASURES: Odds ratios (OR) from multiple logistic regression analysis controlling for relevant variables (type of tobacco use and economic status).
RESULTS: A protective effect of fibre was observed for both oral submucous fibrosis (OSF) and leukoplakia, with 10% reduction in risk per g day-1 ( P < 0.05). Ascorbic acid appeared to be protective against leukoplakia with the halving of risk in the two highest quartiles of intake (versus the lowest quartile: OR = 0.46 and 0.44, respectively; P < 0.10). A protective effect of tomato consumption was observed in leukoplakia and a suggestion of a protective effect of wheat in OSF.
CONCLUSION: In addition to tobacco use, intake of specific nutrients may have a role in the development of oral precancerous lesions.  相似文献   
90.
J Taube  N McWilliam  R Luddington  C D Byrne  T Baglin 《Blood》1999,93(11):3792-3797
Plasma and platelet factor Va represent different substrates for activated protein C (APC). In this study, we have measured platelet-dependent APC resistance and the effect of aspirin and a platelet glycoprotein IIbIIIa antagonist (GR144053F) on this phenomenon. In platelet rich plasma (PRP), progressive APC resistance was observed with increasing platelet activation. APC sensitivity ratios of 1.8, 1.7, and 1.4 were observed after platelet activation with thrombin receptor activating peptide (TRAP), collagen, and A23187, respectively. Ultracentrifugation at 77,000g for 1 hour abolished APC resistance indicating that the phenotype is associated exclusively with the platelet membrane. APC resistance was not observed in the presence of phosphatidylcholine-phosphatidylserine (PCPS) vesicles or purified human plasma lipoproteins. APC resistance was observed in the presence of platelet-derived microparticles, but to a lesser degree than that in the presence of activated platelets. The platelet-dependent APC resistance phenotype was also observed when endogenous APC was generated by Protac (American Diagnostica, Inc, Greenwich, CT). In vitro inhibition of platelet activation with aspirin had no effect, but the fibrinogen receptor antagonist, GR144053F, inhibited platelet-dependent APC resistance. These results indicate that platelet activation results in an APC-resistant phenotype comparable to that observed in the plasma of patients with factor V gene mutations affecting critical APC cleavage sites. This suggests that platelet activation at the site of endothelial damage downregulates a critical natural anticoagulant mechanism. The antithrombotic effect of aspirin may be due to an indirect effect on platelet-dependent APC resistance with reduced platelet retention within a developing thrombus. The more potent antithrombotic effect of glycoprotein IIbIIIa antagonists may in addition be the result of reduced platelet factor Va expression and modulation of the platelet-dependent APC resistance phenotype.  相似文献   
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