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41.
Sulcus vocalis is the presence of a groove extending along the vibratory surface of a vocal fold and may result in dysphonia. Depending on the level of severity, this condition may require treatment involving complicated surgical techniques. Cases of sulcus vocalis are classified as physiological, vergeture, or pouch type. A clear explanation of the etiology has not been established, and the currently proposed congenital origin, as described in the literature, remains controversial. This paper presents findings from monozygotic twin sisters with bilateral sulcus vocalis; these patients had similar morphologies, vibratory characteristics, and vocal quality measurements, which support the theory of a congenital etiology.  相似文献   
42.
Adenocarcinoma of the mammary gland is the leading type of cancer in women. Among these breast cancers those that are estrogen-responsive respond well to existing therapeutic regimens while estrogen non-responsive cancers metastasize widely, demonstrate a high relapse rate, and respond poorly to therapy. Over-expression of the arachidonic acid-metabolizing enzymes cyclooxygenase-2 and lypoxygenases is frequently observed in breast cancer, particularly the non-estrogen-responsive type, suggesting a role of the arachidonic acid (AA) cascade in the growth regulation of these malignancies. Adenocarcinomas of the lungs, pancreas and colon also frequently over-express AA-metabolizing enzymes, and recent evidence suggests that the growth-regulating AA-cascade in these malignancies is under beta-adrenergic control. Our current experiments have therefore tested the hypothesis that in analogy to these findings adenocarcinomas of the breast are also regulated by beta-adrenergic receptors via stimulation of the AA-cascade. Analysis of DNA synthesis by [3H]-thymidine incorporation assays in three estrogen-responsive and three estrogen non-responsive cell lines derived from human breast cancers demonstrated a significant reduction in DNA synthesis by beta-blockers and inhibitors of cyclooxygenase or lipoxygenases in all cell lines. Analysis of AA-release in one of the most responsive cell lines demonstrated a time-dependent increase in AA-release in response to the beta-adrenergic agonist isoproterenol. Analysis by RT-PCR revealed expression of beta2-adrenergic receptors in all cell lines whereas beta1-adrenergic receptors were not found in two of the estrogen non-responsive cell lines. Our data suggest that a significant subset of human breast cancers is under control of beta-adrenergic receptors via stimulation of the AA-cascade. These findings open up novel avenues for the prevention and clinical management of breast cancer, particularly the non-estrogen-responsive types. Moreover, our findings suggest that cardiovascular disease and adenocarcinomas in a variety of organ systems, including the breast may share common risk factors and benefit from similar preventive and treatment strategies.  相似文献   
43.
Higher technetium-99m methoxyisobutylisonitrile (MIBI) uptake in non-small cell lung cancer (NSCLC) has been reported to be associated with a positive response to chemotherapy. It has previously been found that in tumour cells, P-glycoprotein (Pgp) expression is of importance for tracer uptake. However, some studies have indicated that Pgp expression does not play an important role in (99m)Tc-MIBI uptake in NSCLC; indeed, a negative correlation between (99m)Tc-MIBI uptake and Pgp expression has been reported. Against the background of conflicting results, our aim was to evaluate the relationship between (99m)Tc-MIBI uptake, prognosis and Pgp expression in NSCLC. A total of 37 patients with NSCLC underwent (99m)Tc-MIBI single-photon emission tomography (SPET) before chemotherapy. In 19 patients both Pgp and p53 expression, and in two patients only p53 expression (due to the limited biopsy material), were measured with immunohistochemical staining. (99m)Tc-MIBI uptake was significantly higher in responders than in non-responders: 3.09+/-1.14 vs 2.24+/-0.88 ( P<0.03) and 3.09+/-1.08 vs 2.37+/-1.06 ( P<0.05) for the early ratio (ER) and the delayed ratio (DR), respectively. The wash-out rate (WR) of responders was not significantly different from that of non-responders. We found no significant differences in ER, DR and WR among the groups positive or negative for Pgp and p53 status. There was a significant positive correlation between the survival rate and both ER and DR: r=0.49 ( P=0.003) and r=0.40 ( P=0.018), respectively. Patients with ER and DR values above 3 showed significantly longer survival than those with values below 3: 14.7+/-8.5 months vs 7.3+/-5.1 months ( P<0.009) and 13.2+/-8.4 months vs 7.4+/-5.3 months ( P<0.04) for ER and DR, respectively. However, interestingly, and in contrast to expectations, patients with a Pgp score of +2 showed significantly longer survival (12.9+/-6.7 months) than those with Pgp scores of +1 (4.4+/-3.0 months) or - (negative) (3.8+/-2.2 months) ( P<0.009 and P<0.02, respectively). Our results suggest that in NSCLC, patients with higher (99m)Tc-MIBI uptake tend to show a positive response to chemotherapy, and patients with ER and DR values above 3 have a significantly better prognosis. We also found that Pgp expression seems to play only a minor role in (99m)Tc-MIBI uptake. Our finding that patients with ER and DR values above 3 have a better prognosis needs to be confirmed in larger series of patients.  相似文献   
44.
Radiation‐induced mucositis is an acute reaction of the mucosa of patients undergoing head and neck radiotherapy. It can have debilitating and dose‐limiting consequences. There is no consensus on an accepted intervention that significantly reduces its severity. Misoprostol is a synthetic prostaglandin E1 analogue, with properties of a mucosal cytoprotectant. We designed a randomized, double‐blind, placebo‐controlled trial of misoprostol in patients with head and neck cancer. The aim of this study was to determine if topical misoprostol was effective in reducing the severity of radiation‐induced mucositis in patients receiving radical dose radiotherapy. The effect of this intervention on a patient’s general well‐being was also investigated. The primary end‐point of the study was the incidence of Radiation Therapy Oncology Group grade 3 mucositis. Between 1999 and 2002, 83 patients were recruited into the study at Westmead and Nepean Hospitals, Sydney. Forty‐two patients were randomized to receive misoprostol and 41 to receive a placebo. Most patients received radiotherapy in the adjuvant setting (52 of the 83) and had either an oral cavity (42 of the 83) or an oropharyngeal (16 of the 83) cancer. We could not identify any significant difference in the incidence of severe mucositis based on whether patients were allocated to receive misoprostol or placebo. There was no significant difference in the mean area under the mucositis curve (13.2 vs 16.6; P = 0.1). Patients allocated to misoprostol did report slightly increased soreness (7.6 vs 6.9; P = 0.04) and a greater use of analgesics. However, this difference did not translate into a worse feeling of general well‐being as measured by a simple visual analogue scale (5.8 vs 5.2; P = 0.3). In conclusion, we were unable to identify a reduction in radiation‐induced mucositis in patients receiving misoprostol. There is a paucity of high‐level evidence on potentially useful interventions and a continued need for new and innovative research, incorporating quality‐of‐life measurements, in patients experiencing radiation‐induced mucositis.  相似文献   
45.
Australia has the highest incidence of cutaneous squamous cell carcinoma (SCC) in the world. The majority of lesions occur in the head and neck, and regional lymph‐node metastases from cutaneous SCCs, though uncommon, reflect an aggressive manifestation. Surgery and adjuvant radiotherapy are currently considered best practice. Fifty‐two eligible patients during 1980–1997 were identified in a retrospective review of patients treated within the department of Radiation Oncology, Westmead Hospital, Sydney. Relevant data were extracted from the files, referring clinicians and the New South Wales Cancer Council. The median age at diagnosis was 63 years and the majority were men (87%). Unfavourable pathological features were present in many of the patients. Only extranodal spread (P = 0.02) was identified as an independent predictor for locoregional recurrence on multivariate analysis. The cumulative locoregional recurrence rates were 28 and 45% at 2 and 5 years, respectively. The 5‐year cause‐specific survival rate in this study was 65%. We conclude that parotid lymph‐node metastases from cutaneous SCCs of the head and neck are associated with a high rate of locoregional recurrence and cause‐specific mortality despite surgery and adjuvant radiotherapy. The role of altered fractionation after surgery as a means to further enhance locoregional control warrants further investigation.  相似文献   
46.
Purpose: To evaluate the relationship between posterior capsule opacification and pseudoexfoliation syndrome. Methods: The cases which are included in this study were chosen among patients who underwent phacoemulsification and lens implantation 23 pseudophakic eyes 18 pseudoexfoliation syndrome and 78 pseu-dophakic eyes of 54 control subjects were enrolled in this study.  相似文献   
47.
Oesophageal cancer is frequently complicated by malignant fistulae. Necrosis of the tumour following radiotherapy or chemotherapy may lead to the development of fistulae between the oesophagus and adjacent tissues and organs. We report the expansion of an extra-luminal oesophageal cancer after resection, invading the cervico-thoracic spine, fortunately without neurological deficit, and leading to instability and formation of a malignant fistula linking the tracheo-bronchial tree to the subarachnoidal space. To prevent imminent paraplegia and to alleviate severe pain, we rigidly stabilised the spine at the cervico-thoracic junction using an angle-stable system through a single posterior approach. Further postoperative follow-up revealed no signs of neurological deterioration. Cervico-thoracic stability was preserved until the patient died nearly five months postoperatively. This case shows that posterior stabilisation and decompression may be a palliative option for patients with imminent paraplegia and severe pain due to advanced tumour infiltration of the cervico-thoracic spine.  相似文献   
48.
INTRODUCTION: Vertebroplasty is a relatively new procedure for the treatment of vertebral body fractures of different origin. Due to early promising results the rate of performed procedures increases constantly. Indeed an increasing number of partially severe complications are reported. A summary of the existing findings seems therefore necessary. METHODS: On the basis of a medline inquiry important aspects of vertebroplasty in the fields of basic science, diagnostics, indications, contraindications, technique, results and complications were compiled. RESULTS: Especially for the field of indications, possible longterm effects and for the "ideal" technique open questions exist, mainly due to missing prospective, randomized long-term clinical trials. CONCLUSIONS: A final assessment of the significance of vertebroplasty for osteoporotic fractures in comparison to conservative treatment is actually not possible. In contrast vertebroplasty is a therapeutical option for malignomas in selected cases.  相似文献   
49.
50.
The objective of this prospective randomized placebo-controlled study was to determine the effectiveness of 400 mug oral and 400 mug vaginal misoprostol administration for cervical priming 3 h prior to manual vacuum aspiration (MVA) under local anesthesia for voluntary termination of pregnancy before 10 weeks of gestation in comparison with placebo oral or placebo vaginal administration (n=40 in each group). Postmedication cervical dilatation was similar in the oral (mean, 6.6+/-1.5) and vaginal (mean, 7.2+/-0.8) misoprostol groups but significantly higher compared with the oral (mean, 3.4+/-0.2) and vaginal (mean, 3.6+/-1.9) placebo groups. Duration of the procedure was also significantly shorter in the misoprostol groups in comparison with their placebo counterparts. Preoperative bleeding and side effects were more common in the misoprostol groups, but none required medical intervention. Intraoperative bleeding was less in the vaginal misoprostol group compared with the placebo groups. There was no significant difference in terms of visual analogue scores during the procedure, patient satisfaction, days of postoperative bleeding and rate of postoperative complications among the groups. Cervical priming with misoprostol administered orally or vaginally 3 h before MVA for termination of pregnancy under local anesthesia facilitates the procedure by decreasing the need for cervical dilatation and by shortening its duration without improving patients' pain perception and satisfaction mainly due to side effects.  相似文献   
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