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121.
122.
A series of 14 parapharyngeal tumours has been studied with regard to their symptology, pre-operative evaluation and surgical management. High resolution computed tomography is now the best initial diagnostic study because it helps to determine the size and extent of the tumour, differentiate tumours of parotid and extraparotid origin, demonstrate degree of tumour vascularity, separate benign from malignant lesions, plan the surgical approach and predict prognosis.  相似文献   
123.
PURPOSE: The DNA-minor-groove-ligands bisbenzimidazoles Hoechst 33258 and 33342 have been reported to protect against radiation-induced DNA-strand breakage. In order to elucidate the mechanisms of protection by these DNA-binding compounds, pulse radiolysis studies on the reactions of the OH radical, the solvated electron and the H atom with Hoechst as well as OH-radical-induced nucleotide radical quenching by free Hoechst (model level) was investigated. MATERIALS AND METHODS: The pulse radiolysis of Hoechst 33258 and 33342 was studied in N2O and N2O/O2-(4:1)-saturated aqueous solutions in the absence and presence of azide and bromide ions and nucleotides. RESULTS: In a fully scavenged system (3 x 10(-2) mol x dm(-3) t-butanol, N2O/O2-saturated), a transient is formed which in the presence of phosphate buffer is no longer observed. This is assigned metastable quinonoid forms of Hoechst (lambdamax(Hoechst) = 340; lambdamax(transient) = 370 nm) which is generated in protonation/ deprotonation reactions by H+/OH- formed during the pulse. To prevent their formation 10(-3) mol x dm(-3) phosphate buffer was added in all other experiments. The transient spectra formed upon OH-radical attack (k=9 x 10(9) dm3 x mol(-1) x s(-1)) indicate that a major part of the primary OH-adduct radicals undergo rapid transformation (k approximately 5 x 10(5) x s(-1)), attributed to water elimination yielding an N-centered radical. This intermediate, also generated by N3. (k = 4 x 10(9) dm3 mol(-1) x s(-1)), subsequently complexes with a Hoechst molecule [k = 8 x 10(8) dm3 x mol(-1) x s(-1) epsilon(440 nm) = 1.4 x 10(4) dm3 mol(-1) x cm(-1)]. The N-centered radical does not react with O2 (k < 5 x 10(5) dm3 mol(-1) x s(-1)), but reacts readily with the superoxide radical (k= 1.0 x 10(9) dm3 x mol(-1) x s(-1)). Hoechst reacts with the peroxyl radicals derived from uridine (k approximately 5 x 10(6) dm3 x mol(-1) x s(-1)) or 5'-UMP (k approximately 1 x 10(7) dm3 mol(-1) x (s-1)), but not with the less oxidizing (e.g. methylperoxyl radical) yielding intermediates whose spectral properties are similar to those of the N-centered radical. However, they decay at a much lower rate (2k approximately 1 x 10(8) dm3 mol(-1) x s(-1)) than the N-centered radicals generated by N3. (2k= 1.1 x 10(9) dm3 x mol(-1) s(-1)), and it has been suggested that these peroxyl radicals form adducts rather than undergoing electron transfer. The H atom (k= 7 x 10(9) dm3 x mol(-1) x s(-1)) and the solvated electron (k= 2.3 x 10(10) dm3 x mol(-1) x s(-1)) yield, albeit noticeably different, H-adduct radicals which also strongly absorb in the 440 nm region. The reduction potential of Hoechst 33258 has been determined electrochemically at 0.84-0.90 V vs. NHE at pH 6.8. CONCLUSION: Hoechst reacts fast only with strongly oxidizing radicals by electron transfer (e.g. with the adenine-and guanine-derived heteroatom-centered radicals), but also more slowly with nucleo-base-derived peroxyl radicals, here albeit via addition. This may have important implications with regard to its protection owing to DNA-radical quenching under oxic vs. anoxic conditions.  相似文献   
124.
OBJECTIVE: The objective of this study was to review the outcome of surgical management in patients of jugular paragangliomas. STUDY DESIGN: We conducted a retrospective case review. SETTING: Tertiary care otology and skull base center. MATERIALS AND METHODS: Fifty-five patients with the diagnosis of a jugular paraganglioma (Fisch Class C and D Glomus Jugulare) were managed over a period of 15 years. All patients with adequate follow up and complete records (53 cases) were reviewed with emphasis on the results of surgical management and the factors influencing them. INTERVENTION: All 53 patients were managed with a view to surgically extirpate the tumor. The primary approach was the infratemporal fossa approach-Type A used in the majority of the patients. In eight cases, the procedure was staged owing to the presence of large intracranial extension. Three patients required additional procedures to ameliorate the after-effects of lower cranial nerve resection. RESULTS: Gross total tumor removal was achieved in 49 patients. There were five cases of recurrence. Coupled with the residual tumors in five patients, the surgical control achieved was 83%. There was no perioperative mortality. There were two cases of postoperative cerebrospinal fluid leak, both of which required surgical exploration and closure. The facial nerve was resected in seven patients. The overall preservation rate of clinically uninvolved lower cranial nerves was 75%. CONCLUSIONS: The low level of complications along with a high surgical control achieved makes surgery the primary mode of treatment in the vast majority of these tumors, regardless of the size and location.  相似文献   
125.
A case of a child with bilateral fleshy limbal masses with a coloboma of the right upper lid is discussed. Systemic examination revealed two patches of alopecia on the right frontoparietal and right occipital areas of the scalp. Punch biopsy and histopathological examination led to the diagnosis of Linear Nevus Sebaceus Syndrome (LNSS) with bilateral complex limbal choristomas. The authors have stated that they do not have a significant financial interest or other relatioship with any product manufacturer or provider of services discussed in this article. The authors also do not discuss the use of off-label products, which includes unlabeled, unapproved, or investigative products or devices.  相似文献   
126.
OBJECTIVES: To study the use of drotaverine hydrochloride for acceleration of labor and relief of labor pains. METHODS: In this double-blind placebo-controlled randomized study, 100 primigravidas in uncomplicated spontaneous labor at term were given drotaverine hydrochloride or placebo (distilled water) intramuscularly. Labor events, including pain (assessed by a visual analog scale and a verbal rating scale), neonatal outcome, and side effects of the drug were recorded. Student's t-test was used for analysis. RESULTS: Forty-four patients in the drug group and 40 in the placebo group had complete data for analysis after decoding. In drotaverine group, there was a mean 15% reduction in the duration of the first stage of labor and a mean 19% reduction in the second stage. The maximum shortening of the first stage (28%) was observed when drotaverine was administered when cervical dilatation was 4 cm (P=0.044). There were no adverse fetal effects, but atonic postpartum hemorrhage was more common in the drotaverine group. There was no relief of pain with the drug except in the fourth stage of labor. CONCLUSIONS: Drotaverine hydrochloride is safe and effective in accelerating labor, but not effective in lessening labor pain.  相似文献   
127.
128.
Oral manifestation of tuberculosis is uncommon Tongue is the most common oral site of involvement, where the presentations are varied. Here we report a case of primary lingual tuberculosis with an unusual presentation as a cold abscess.  相似文献   
129.
The global maternal mortality ratio (MMR) of 400 per 100,000 live births results in an estimated 529,000 maternal deaths annually. Most of these deaths occur in developing countries and only about 1% in developed countries. Besides mortality data, the identification and accurate documentation of “near-miss” morbidity (a more sensitive index) is extremely important to assess the quality of health care systems. It can suitably guide to adopt appropriate measures to reduce maternal mortality and morbidity. Haemorrhage remains a major cause of maternal mortality in both developing and developed countries followed by anaemia and infection, which are more common in developing countries. Post-partum haemorrhage (PPH) is a frequent complication of delivery. PPH occurred in 10.5% of all live births worldwide resulting in 13,795,000 cases in the year 2000. The case fatality rate for PPH was 1% and there were 132,000 deaths attributable to PPH. Anaemia as a consequence of PPH was estimated to occur in 1.6 million women every year. Thus, the prevention and adequate management of obstetric haemorrhage are likely to result in a significant reduction in the MMR and in the less frequently monitored “near-miss” morbidity. Strategies to be adopted with regard to PPH in developing countries may differ from those routinely available and practised in developed countries because of limited access to health care facilities and low institutional delivery rate in the former countries. Some low cost, simple techniques to prevent and manage PPH are described. These need to be tested in a wider population to determine which is most suitable for a particular area or country. The mortality and “near-miss” morbidity data should be continually assessed and only then will the impact of these strategies be known. First level midwifery care plus backup by well-equipped hospitals must be developed concomitantly. Anyone can conduct a normal delivery when all is going well but only those with good clinical judgement and the necessary skills will be able to anticipate and manage a problem. This is especially important in the context of PPH where the under-estimation of blood loss coupled with the rapidity of development of serious consequences is the key issue.  相似文献   
130.
PURPOSE: Amygdala plays a very important role in the mediation of emotional and affective components of pain. Bilateral amygdalectomy increases the threshold for vocalization, a measure of emotional reactivity, without any change in the tail flick latency. The present work was designed to study the recovery of emotional nociceptive behaviour following neural tissue transplantation in lesioned rats. METHODS: In a group of adult wistar rats lesions of the central nucleus of amygdala (CeA) were produced electrolytically. In a separate group of rat's amygdalar tissue was transplanted at the lesioned site 2 days thereafter. The vocalization tests, viz. simple vocalization (SV) and vocalization after discharge (VA), which were used to study the emotional nociceptive behaviour were carried out both before and after pro-ducing lesion/transplant. RESULTS: Bilateral CeA lesions increased the thresholds for SV and VA significantly (p < 0.001), indicating analgesia. Following amygdalar tissue transplantation a significant decrease (p < 0.05) in the thresholds were observed when compared with the lesioned group, although when compared with the basal data it showed an increase (p<0.05). CONCLUSIONS: The results indicate a partial recovery of the vocalization response following amygdalar tissue transplantation.  相似文献   
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