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151.
The aim of this study is to analyze the incidence and risk factors for pneumonitis when immune checkpoint inhibitors (ICIs) are combined with palliative thoracic radiotherapy (RT) for lung cancer. We retrospectively evaluated 29 patients with lung cancer who received ICIs after palliative thoracic RT (30 Gy in 10 fractions). Their ICIs were pembrolizumab (n = 17), nivolumab (n = 8) and atezolizumab (n = 4). Median follow-up period was 10 months. The median interval between starting RT and starting ICI was 25 days. Pneumonitis events were grade 1 (n = 10; 34%), grade 2 (n = 4; 14%) and grade 3 (n = 3; 10%). Obstructive pneumonia was significantly associated with grade ≥ 2 pneumonitis (P = 0.036). Age, sex, ICI agent, interval between RT and ICI and history of ICI before RT were not associated with grade ≥ 2 pneumonitis. Tumor volume; Brinkman index; dosimetric factors, such as lung V5, V10, V20, V30 and mean lung dose (MLD); lactate dehydrogenase; and C-reactive protein did not significantly differ between the grade ≤ 1 and grade ≥ 2 pneumonitis groups. Levels of sialylated carbohydrate antigen KL-6 were evaluated in 27 patients before RT; they significantly differed between patients with grade ≤ 2 pneumonitis (mean: 431 U/ml) and those with grade ≥ 3 pneumonitis (mean: 958 U/ml; P < 0.001). Patients who receive ICI after palliative thoracic RT should be carefully followed-up, especially those who have had obstructive pneumonia or high KL-6 levels.  相似文献   
152.
 Although many of the behavioral effects of cocaine are widely believed to be mediated by blockade of dopamine transporters, recent studies suggest that norepinephrine (NE) may play a modulatory role. In this study, selective and nonselective β-adrenergic receptor antagonists were administered alone or in combination with cocaine (2.5 mg/kg, IP) to rats trained to discriminate a low dose (2.5 mg/kg) from a high dose of cocaine (10 mg/kg) in a two-lever, FR10 drug discrimination procedure. The central β21-adrenergic antagonists (–)-propranolol and tertatolol, and the β2-adrenergic antagonist, ICI 118,551, produced high-dose appropriate responding in a dose-related manner when administered (IP) in combination with the low training dose of cocaine. In contrast, neither the peripheral β21-adrenergic antagonist, nadolol, nor the central β1-adrenergic antagonist, betaxolol enhanced the behavioral effects of the low dose of cocaine in a manner comparable with that produced by compounds with central β2-adrenergic antagonist properties. Also in contrast to findings obtained using β-adrenergic antagonists, neither the α1-adrenergic agonist cirazoline, nor the α2-adrenergic ligands (±)-efaroxan and UK-14304 enhanced the behavioral effects of the low dose of cocaine. Overall, these results suggest that central β2-adrenergic receptors may play a modulatory role in the discriminative stimulus effects of cocaine. Received: 29 October 1996 / Final version: 4 February 1997  相似文献   
153.
主要研究了正交频分复用(OFDM)系统基于线性时变(LTV)模型的子载波间干扰(ICI)消除算法。在LTV模型中采用双重ICI消除算法可以达到比较好的性能,然而由于导频处的估计值准确度有限,限制了算法性能的进一步提升。提出了一种基于导频簇方案的双重ICI消除算法,采用基于导频簇的梳状导频结构,大幅降低导频处的ICI影响,取得了较好的效果。  相似文献   
154.
ICI 128,436 (3-(4-bromo-2-fluorobenzyl)-4-oxo-3H-phthalazin-1-ylacetic acid) is a chemically novel, potent inhibitor of aldose reductase. It inhibits partially purified aldose reductase isolated from a number of sources including human tissue (human lens - IC50 2.0 X 10(-8) mol/L). Dulcitol accumulation in erythrocytes and sciatic nerves of galactose loaded rats was inhibited by five days of treatment with ICI 128,436 (oral ED50's 2.21 mg/kg and 8.56 mg/kg, respectively). On oral administration for five days to streptozotocin diabetic rats, ICI 128,436, reduced sorbitol levels in sciatic nerve, lens, retina, and renal cortex. The ED50 for inhibition of nerve sorbitol accumulation was 5 mg/kg. The effect of a single dose of ICI 128,436 in diabetic rats was prolonged, with little increase in nerve sorbitol for 48 hours. No tolerance to the ability of ICI 128,436 to reduce nerve sorbitol was found on treatment for 74 days. ICI 128,436 was effective in rodent models of the neural and lenticular complications of diabetes. At doses as low as 25 mg/kg/d it completely prevented the development of cataracts in diabetic rats. The deterioration in motor nerve conduction velocity velocity found in diabetic rats was ameliorated by treatment with ICI 128,436 (3.125 mg/kg/d). Thus, ICI 128,436 constitutes a chemically novel aldose reductase inhibitor that is now being assessed for therapeutic value in the diabetic patient.  相似文献   
155.
156.
Lung cancer remains the leading cause of cancer deaths in the United States. In the past decade, significant advances have been made in the science of non–small cell lung cancer (NSCLC). Screening has been introduced with the goal of early detection. The National Lung Screening Trial found a lung cancer mortality benefit of 20% and a 6.7% decrease in all-cause mortality with the use of low-dose chest computed tomography in high-risk individuals. The treatment of lung cancer has also evolved with the introduction of several lines of tyrosine kinase inhibitors in patients with EGFR, ALK, ROS1, and NTRK mutations. Similarly, immune checkpoint inhibitors (ICIs) have dramatically changed the landscape of NSCLC treatment. Furthermore, the results of new trials continue to help us understand the role of these novel agents and which patients are more likely to benefit; ICIs are now part of the first-line NSCLC treatment armamentarium as monotherapy, combined with chemotherapy, or after definite chemoradiotherapy in patients with stage III unresectable NSCLC. Expression of programmed cell death protein-ligand 1 in malignant cells has been studied as a potential biomarker for response to ICIs. However, important drawbacks exist that limit its discriminatory potential. Identification of accurate predictive biomarkers beyond programmed cell death protein-ligand 1 expression remains essential to select the most appropriate candidates for ICI therapy. Many questions remain unanswered regarding the proper sequence and combinations of these new agents; however, the field is moving rapidly, and the overall direction is optimistic.  相似文献   
157.
Salem H  Mostafa T 《Andrologia》2012,44(2):125-129
This study aimed at assessing the effect of regular use of intracorporeal injection (ICI), sildenafil citrate and vacuum constriction device (VCD) on cavernous smooth muscle and erectile activity. One hundred and sixty-five patients with organic erectile dysfunction were investigated for 3 months. The patient and his partner were classified prospectively after proper counselling: group I (n = 56) received ICI twice per week; group II (n = 55) received sildenafil 100 mg twice per week; and group III (n = 54) used VCD twice per week. Duplex ultrasound was carried out before and after treatment, and then, the patients were followed up for a month to assess the resumption of unaided erection. The results showed that there was significant improvement in mean peak systolic velocity (PSV) and mean cavernosal artery diameter (CAD) at the end of the treatment in all groups, being higher in the ICI group than in the other two groups. Also, the percentage of patients who resumed unaided intercourse were higher in the ICI group compared with the other two groups (17.9%, 9.1% and 3.7% respectively). It is concluded that repeated regular use of ICI, sildenafil or VCD by patients with organic erectile dysfunction has a positive impact on their cavernous blood flow and erectile activity.  相似文献   
158.
In man, circulating adrenaline has little or no direct effect on the control of blood pressure. A small proportion of adrenaline secreted by the adrenal medulla is accumulated in sympathetic nerve endings and may be re-released by sympathetic nerve stimulation. Recent pharmacological studies have suggested that adrenaline acts on a presynaptic β-receptor on sympathetic nerve endings to facilitate noradrenaline release, and it has been proposed that adrenaline re-released from these nerve endings is therefore a functionally important “co-transmitter”. Intermittently elevated secretion of adrenaline from the adrenal medulla could therefore lead indirectly to a sustained increase in neuronal release of noradrenaline and hence to hypertension.  相似文献   
159.
160.
1. Intravenous infusions of UK14304 (0.3-10 micrograms/kg per min) in pithed rat produced dose-dependent pressor responses which were not affected by prazosin (10 micrograms/kg) but were reduced by yohimbine (0.3 mg/kg). 2. Pressor responses to noradrenaline (0.1 micrograms/kg), phenylephrine (1 micrograms/kg) and vasopressin (10 mU/kg) were enhanced during infusions of UK14304 (0.03-1 micrograms/kg per min). Likewise, pressor responses to spinal sympathetic stimulation were enhanced during infusions of low concentrations of UK14304 (0.03-0.3 microgram/kg per min) but were reduced during infusion of a higher concentration of UK14304 (10 micrograms/kg per min). 3. After administration of yohimbine (0.3 mg/kg) or the calcium channel blocking drug diltiazem (infused at 50 micrograms/kg per min), pressor responses to noradrenaline and UK14304 were reduced, and responses to noradrenaline during infusion of UK14304 were not enhanced. 4. Prazosin (10 micrograms/kg) revealed a secondary depressor component in the response to sympathetic stimulation which is due to beta-adrenoceptor activation, since it was abolished by ICI 118551 (0.3 mg/kg). In the presence of ICI 118551 plus prazosin, pressor responses to sympathetic stimulation were enhanced during infusions of UK14304. 5. The depressor response to nitroprusside and the depressor component of responses to sympathetic stimulation after prazosin were enhanced during infusions of UK14304 at concentrations that increased the blood pressure. 6. The findings show that alpha 2-adrenoceptor activation enhanced the pressor responses to sympathetic nerve stimulation, noradrenaline, phenylephrine and vasopressin in the pithed rat and beta-adrenoceptor activation produced depressor responses which increased with increasing blood pressure.  相似文献   
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