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11.
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Parathyroid carcinoma (PC) is a rare malignancy that poses a diagnostic challenge on histologic examination. We analyzed various clinicopathologic features of PC. Pathology reports and slides were reviewed to evaluate the diagnostic histopathologic features of archived cases of PC from the years of 2004–2018. The study cohort comprised twenty cases of PC. The median age was 49 years (range 21–73 years) with equal gender distribution (M:F = 1:1). Most patients presented with symptoms of hypercalcemia (n = 7, 54%). Serum calcium and serum parathyroid hormone were elevated in all but one patient. The right inferior parathyroid was commonly involved (n = 8/14, 57%). The mean tumor size was 2.4 cm (range 0.8–3.5 cm). On frozen section examination, PC was diagnosed in 8 out of 9 cases. Vascular (n = 19/20, 95%) and soft tissue invasion (n = 10/20, 50%) were the most common characteristic histologic findings. Capsular invasion was identified in all cases. Perineural invasion or metastasis at presentation was absent in all cases. Other histological features noted were intratumoral fibrous bands (70%), nodular growth pattern (70%), moderate nuclear atypia (30%), prominent nucleoli (20%), and necrosis (20%). Regional lymph nodes were negative for metastatic disease in all cases (n = 10). Eight out of 16 patients received adjuvant radiotherapy. Follow-up was available in 16 cases (median 21.5 months). Two patients died of disease. Vascular and soft tissue invasion are the most common diagnostic histologic features of PC. Capsular invasion is important to distinguish PC from its benign counterparts. Intraoperative frozen section examination can be used for accurate diagnosis and surgical management.  相似文献   
13.
A key recommendation of the National AIDS Control Programme‐IV of India was to develop new strategies for geo‐prioritization of the human immunodeficiency virus (HIV) epidemic. We conducted this study to categorize the districts in Maharashtra (India) based on a multidimensional framework for geo‐prioritization of services. Programmatic data on trends of HIV prevalence, coverage of marginalized populations and vulnerability factors were included. A composite indicator based on these was developed, and the cumulative score was calculated for each district. HIV prevalence among general population has declined steadily from 0.60% in 2007 to 0.33% in 2017. The programme coverage was stable but inadequate for men who have sex with men (MSM). The coverage for female sex workers (FSWs) was inadequate and reduced over time. Nine districts were categorized as high priority, 13 as moderate priority and 11 were classified as low‐priority districts based on burden and vulnerability for HIV. The high‐priority districts were Pune, Solapur and Yavatmal for FSW interventions and Pune, Thane and Latur for MSM interventions. This multidimensional indicator is based on existing programmatic data, dynamic and can be made state‐specific. It is useful to categorize and prioritize districts for allocation of resources and geo‐prioritization of services in resource limited settings.  相似文献   
14.
Isolated parotid gland tuberculosis in the clinical absence of tuberculosis elsewhere in the body, is a rare clinical entity. It is often misdiagnosed as parotid gland tumour in the absence of symptoms suggestive of tuberculosis. We are presenting this case to highlight the unusual solitary nature of the lesion, the absence of any other tuberculous focus in the body, the inconclusive findings of the pre-operative investigations like fine needle aspiration cytology (FNAC), and computed tomography (CT), and the need for histopathology for definitive diagnosis.  相似文献   
15.
Transanal, end-to-end, rectorectal anastomosis (TERA) is a new technique for the surgical correction of rectal atresia. Hitherto performed abdominoperineal or sacroperineal procedures entailed major traumatizing surgery with an inherent risk of complications. The rationale of TERA is based on three factors: (1) the anorectal canal distal to the atresia is normally developed, as are the sphincteric muscles surrounding it; (2) the anorectum can be preoperatively dilated to allow a transanal anastomosis of good size; and (3) the atretic segment can be effectively "intussuscepted" into the anal canal, almost up to the anal verge, by an oversized metal bougie passed through the sigmoid colostomy. A midline sagittal incision over the metal bougie exposes the rectal pouch, which is mobilized from the surrounding muscle fibers, and a direct, end-to-end anastomosis is performed. This technique has been successfully used in two cases of rectal atresia having a gap between the two pouches.  相似文献   
16.
As shown earlier p-XSC inhibits DMBA-induced mammary cancer in female CD rats. This inhibition is due, in part, to inhibition of DMBA-DNA adduct formation in the target organ. We have now utilized the DMBA-DNA binding assay to evaluate the chemopreventive potential of positional isomers of XSC (o-, m- and p-XSC) applied at selenium doses of 5 and 15 ppm; p-XTC, the sulfur analog of p-XSC, was used at an equimolar dose to determine whether selenium is required for the observed inhibitory effect. Selenium and sulfur compounds were administered in a semipurified high-fat diet (23.5% corn oil). Rats were fed for 1 week prior to oral administration of a single dose of [H-3]DMBA (5 mg/rat); animals were sacrificed 24 h later, DNA was isolated from mammary fat pads and levels of total binding were determined. All agents produced a dose-dependent inhibition of DMBA-DNA binding in the mammary tissues. The inhibition at 5, respectively 15 ppm Se in the form of XSC isomers and at 30 mu M, respectively 90 mu M in the form of p-XTC was: o-XSC (27%, 42%); m-XSC (32%, 47%); p-XSC (22%, 29%); and p-XTC (10%, 20%); only inhibition by dietary o-XSC and m-XSC at 15 ppm Se reached statistical significance (p<0.05). Thus, o-XSC and m-XSC equally inhibit DMBA-DNA binding and both are better inhibitors than p-XSC; the latter appears to be slightly more effective than its sulfur analog p-XTC. Clearly, the structure of the selenium-containing compound is a critical factor in determining the extent of inhibition of DMBA-DNA binding. The described short-term in vivo assay may constitute the basis for future selection of chemopreventive agents in the rat mammary tumor model system.  相似文献   
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Summary Although 5-hydroxytryptamine (5-HT) increases porcine atrial force and rate via 5-HT4 receptors, its effect on left ventricular contractility is not known. Therefore, using the maximum rate of rise of left ventricular pressure (LVdP/dtmax) as an index of cardiac contractility, we have attempted to analyze the possible role of ventricular 5-HT4 receptors in the anaesthetized pig. The full agonists at 5-HT4 receptors, 5-HT and 5-methoxytryptamine (each 3, 10 and 30 g · kg–1), and the -adrenoceptor agonist, isoprenaline (0.01, 0.03 and 0.1 g · kg–1), increased heart rate, LVdP/dtmax and cardiac output. For a given degree of tachycardia, the increase in LVdP/dtmax by isoprenaline was substantially more than that observed with either 5-HT or 5-methoxytryptamine. The 5-HT4 receptor partial agonist, renzapride (3, 10, 30, 100 and 300 g · kg–1), also increased heart rate and LVdP/dtmax dose-dependently. When the heart was paced at 150 beats · min–1, increases in LVdP/dtmax as well as cardiac output (except with the highest doses) by 5-HT, 5-methoxytryptamine and isoprenaline were clearly attenuated. However, the magnitude of attenuation of LVdP/dtmax responses by cardiac pacing was more marked in the case of 5-HT and 5-methoxytryptamine than with isoprenaline.The effects of renzapride (300 g · kg–1) and tropisetron (0.3 and 3 mg · kg–1) on increases in heart rate and LVdP/dtmax by 5-HT, 5-methoxytryptamine and isoprenaline were also studied. In the absence of atrial pacing, both renzapride and tropisetron (3 mg · kg–1) effectively antagonized the responses to 5-HT and 5-methoxytryptamine; except for some decrease in the LVdP/dtmax response by tropisetron, the effect of isoprenaline remained essentially unchanged after the antagonists. During atrial pacing, renzapride significantly antagonized the responses to the first two doses of 5-HT, but the responses to the highest 5-HT dose and to 5-methoxytryptamine remained unaffected. Though, particularly after its higher dose, tropisetron reduced the responses to 5-HT and 5-methoxytryptamine, isoprenaline responses were also affected.The above results show that a significant part of the increase in LVdP/dtmax by 5-HT receptor agonists in the anaesthetized pig is a consequence of tachycardia elicited by these compounds via 5-HT4 receptors. Since the increase in LVdP/dtmax, compared to tachycardia, was much less with 5-HT and 5-methoxytryptamine than with isoprenaline, and since the antagonism by renzapride and tropisetron against 5-HT and 5-methoxytryptamine during atrial pacing was relatively weaker and/or unspecific, it appears unlikely that the increase in LVdP/dtmax, during atria] pacing is mediated by ventricular 5-HT4 receptors. This view is substantiated by our recent in vitro experiments where 5-HT (0.01 to 100 mol/l) failed to significantly increase contractions of porcine left ventricular trabeculae.Correspondence to P. R. Saxena at the above address  相似文献   
19.
Abstract: The present study investigated the effects of dopamine on the canine external carotid circulation. One min. intracarotid artery (i.c.) infusions of dopamine (10–310 μg min.?1) produced dose‐dependent decreases in the canine external carotid conductance without affecting blood pressure or heart rate. This effect was mimicked by the D1/2‐like receptor agonist apomorphine (1–310 μg min?1), but not by the D2‐like receptor agonist, bromocriptine (31–310 μg min.?1). In contrast, fenoldopam (1–310 μg min.?1, intracarotid), a D1‐like receptor agonist, produced dose‐dependent increases in external carotid conductance. The vasoconstrictor response to dopamine was abolished after intravenous administration of the antagonists, phentolamine (α1/2; 2000 μg kg?1) or rauwolscine (α2; 100 μg kg?1), but remained unaffected after prazosin (α1; 100 μg kg?1) or haloperidol (D2‐like; 1000 μg kg?1). Interestingly, after phentolamine not only were the vasoconstrictor responses to dopamine abolished, but even a dose‐dependent vasodilator component was unmasked. These vasodilator responses to dopamine remained unchanged after intravenous haloperidol or propranolol (1000 μg kg?1 each). On the other hand, the vasodilator responses to fenoldopam, which remained unchanged after intravenous saline (0.1 ml kg?1), propranolol (1000 μg kg?1) or vagosympathectomy, were abolished by the D1‐like receptor antagonist, SCH‐23390 (10 μg kg?1). Lastly, the responses to dopamine and fenoldopam were not significantly altered after intraperitoneal pretreatment with reserpine (5 mg kg?1; ?24 hr). The above results suggest that the canine external carotid vasoconstrictor responses to dopamine: (i) are mainly mediated by α2‐adrenoceptors; and (ii) overshadow a vasodilator component, which involves vascular D1‐like receptors.  相似文献   
20.
Objectives: To describe an approach based on initial tissue-conserving surgery used to obtain histologically determined prognostic information that has therapeutic implications and the potential to enhance preservation of function. Study Design: Analysis of a group of patients with head and neck cancer treated initially with tissue-conserving surgery based on Mohs' histographic sectioning and selected neck dissection to derive histologically determined prognostic information with therapeutic implications and preservation in function. Methods: This study is primarily based on an analysis of patients from January 1, 1989, through June 4, 1996 assigned to a protocol evaluating resection of oral cavity squamous cell cancer with margin control using Mohs' histographic technique and/or a group of patients with neck assessment of N0 on clinical examination who are undergoing supraomohyoid neck dissections. Results: Thirty-three primary tumor resections were performed using the Mohs' technique, and 54% required two or more Mohs' sections before clear histologic margins were obtained following resection based on clinically determined negative margins. There were 44 patients who underwent unilateral or bilateral supraomohyoid neck dissections, and 33% had occult, histologically positive nodes. When compared with the disease of the neck specimens, a preoperative computed tomography scan had a sensitivity of 25%, a specificity of 77%, and an accuracy of 63%. Conclusions: This report describes the effectiveness of Mohs' histographic sectioning and selective neck dissection as a means of determining prognostic information that can be used to develop a focused and cost-effective treatment program that, along with contemporary reconstructive techniques, provides a potential enhancement of function preservation. Laryngoscope, 108:1599–1604, 1998  相似文献   
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