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Mirror movements (MM) occur in early, asymmetric Parkinson's disease (PD). To examine the pathophysiology of MM in PD, we studied 13 PD patients with MM (PD-MM), 7 PD patients without MM (PD-NM), and 14 normal subjects. Cross-correlogram did not detect common synaptic input to motoneuron pools innervating homologous hand muscles in PD-MM patients. Transcranial magnetic stimulation studies showed no significant difference in ipsilateral motor-evoked potentials between PD-MM patients and normal subjects. The MM side of PD-MM patients showed a slower increase in ipsilateral silent period area with higher level of muscle contraction than the non-MM side and normal subjects. There was less interhemispheric inhibition (IHI) at long interstimulus intervals of 20 to 50 ms in PD-MM than PD-NM. IHI reduced short interval intracortical inhibition in normal subjects and PD-NM, but not in PD-MM. IHI significantly increased intracortical facilitation in PD-MM and PD-NM patients, but not in normal subjects. Our results suggest that MM in PD is due to activation of the contralateral motor cortex. PD-MM patients had reduced transcallosal inhibitory effects on cortical output neurons and on intracortical inhibitory circuits compared to PD-NM patients and controls. These deficits in transcallosal inhibition may contribute to MM in PD patients.  相似文献   
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Fever is a phylogenetically conserved biological phenomenon and a common consequence of infection. Here, we examine in vitro and in vivo the effect of febrile temperature on dendritic cells (DC), a key antigen-presenting cell in the immune system. Elevated temperatures are observed to cause immature DC to mature, specifically through elevation of intracellular levels of hsp90. Surprisingly, even brief exposure to elevated temperatures has a powerful effect on the immunostimulatory capacity of DC. These results bear on the mechanisms of the salutary effects of fever as well as of behavioral elevations of temperature such as saunas and warm blankets.  相似文献   
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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   
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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   
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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   
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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   
10.
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   
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