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1.
Focused ultrasound is used to create local foci of lesions in the myocardium. It is shown that this method can be used for the treatment of monofocal tachycardias. The effect of focused ultrasound on the myocardium, coronary artery, and atrioventricular node is studied in experiments on dogs, and the ultrasound-destroyed zones of the myocardium are investigated morphologically. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N o 7, pp. 104–107, July, 1994 Presented by F. G. Uglov, Member of the Russian Academy of Medical Sciences  相似文献   
2.
We have previously found low levels of C1 and C4 INH in the sera of chronic lymphocytic leukaemia (CLL) patients. Hypocomplementaemia was supposed to be the consequence of a permanent activation of the classical pathway. We have compared the levels of C1 INH-C1rC1s and C1q-FN complexes in the sera of 95 CLL patients and 100 healthy controls, because these complexes are known to be formed in the early stage of classical pathway activation. A significant increase in the level of both types of complexes was found in sera of CLL patients as compared to the controls. These findings support the assumption that the classical complement pathway is activated in the patients with CLL.  相似文献   
3.
PURPOSE: Previous studies have established that patients with desmoplastic melanoma (DM) have thicker primary tumors. Consequently, comparisons with other forms of melanoma have been strongly biased by differences in Breslow stage. This is the first case-matched control study comparing DM with other forms of melanoma. PATIENTS AND METHODS: From a database of 3,202 melanoma patients treated at one institution, 89 patients with DM and 178 case-matched control patients (2:1) were identified by matching for tumor thickness, age, sex, and year of diagnosis. Clinical, pathologic, and outcome information was obtained from chart review. RESULTS: Controls were matched successfully to patients for tumor thickness, age, sex, and year of diagnosis. Presentation with American Joint Committee on Cancer stage III or IV disease is less common in patients with DM compared to case-matched control patients (5% v 21%; P < .001). Re-excisions to obtain clear surgical margins are required more often in patients with DM compared to case-matched control patients (21% v 6%; P < .001). Risk of positive sentinel nodes is lower in patients with DM compared to case-matched control patients (8% v 34%; P = .013). Despite these differences, survival rates of patients with DM are the same as case-matched control patients. CONCLUSION: Use of case-matched control patients matched for tumor thickness avoids biases introduced by the advanced Breslow stage of DMs. DMs are more locally aggressive than thickness-matched controls, and positive sentinel nodes are limited to patients with thick primary tumors. Importantly, patients with DM have survival rates similar to patients with other melanomas of similar thickness.  相似文献   
4.
To examine the impact of exercise test (bicycle ergometry) and exercise-induced transient ischemic changes in ST segment on signal-averaged ECG parameters, the authors studied a homogeneous group including 65 patients (62 males and 3 females) with a 2-3-week history of primary myocardial infarction. The findings showed that induced myocardial ischemia caused no significant changes in signal-averaged ECG and late potentials, exercise might induce late potentials without clear-cut ECG signs of myocardial ischemia. It was also indicated that exercise-labile late potentials were significantly more frequently associated with the development of ventricular arrhythmias than steady late potentials.  相似文献   
5.
BackgroundProgrammed death ligand 1 (PD-L1) contributes to tumor immunosuppression and is upregulated in aggressive meningiomas. We performed a phase II study of nivolumab, a programmed death 1 (PD-1) blocking antibody among patients with grade ≥2 meningioma that recurred after surgery and radiation therapy.MethodsTwenty-five patients received nivolumab (240 mg biweekly) until progression, voluntary withdrawal, unacceptable toxicity, or death. Tumor mutational burden (TMB) and quantification of tumor-infiltrating lymphocytes (TIL) were evaluated as potential immunocorrelative biomarkers. Change in neurologic function was prospectively assessed using the Neurologic Assessment in Neuro-Oncology (NANO) scale.ResultsEnrolled patients had multiple recurrences including ≥3 prior surgeries and ≥2 prior courses of radiation in 60% and 72%, respectively. Nivolumab was well tolerated with no unexpected adverse events. Six-month progression-free survival (PFS-6) rate was 42.4% (95% CI: 22.8, 60.7) and the median OS was 30.9 months (95% CI: 17.6, NA). One patient achieved radiographic response (ongoing at 4.5 years). TMB was >10/Mb in 2 of 15 profiled tumors (13.3%). Baseline TIL density was low but increased posttreatment in 3 patients including both patients with elevated TMB. Most patients who achieved PFS-6 maintained neurologic function prior to progression as assessed by NANO.ConclusionNivolumab was well tolerated but failed to improve PFS-6, although a subset of patients appeared to derive benefit. Low levels of TMB and TIL density were typically observed. NANO assessment of neurologic function contributed to outcome assessment. Future studies may consider rationally designed combinatorial regimens.  相似文献   
6.
Enhanced viral transmission and escape from vaccine–elicited neutralizing antibodies drive worldwide spread of SARS-CoV-2 variants and promote disease progression. However, the impact of specific spike mutations that are carried by different viral variants on viral infectivity and neutralization sensitivity has not been completely defined. Here, we use pseudoviruses to assess the contribution of spike mutations within the Receptor Binding Domain (RBD) and the Furin Cleavage Site (FCS), and appear in circulating viral variants, on viral infectivity and neutralization potential against sera that was drawn from fully vaccinated individuals. Our functional analysis demonstrates that single, P681H, P681R or A701V–FCS mutations do not play a role in viral infectivity and neutralization potential. However, when in conjunction with the RBD–N501Y mutation, viral infectivity is enhanced. Similarly, combining the E484K–RBD mutation to the spike that carries FCS mutations reduces neutralization sensitivity with no effects on viral infectivity. Employing a similar approach onto the spike from Delta or Lota SARS-CoV-2 variants further reveals that specific RBD mutations affect neutralization sensitivity or viral infectivity differently. Our results validate the efficacy of the Pfizer third dose vaccine against Delta and Lota SARS-CoV-2 variants, and outline the significance of distinct RBD mutations in promoting viral infectivity and neutralization sensitivity to post–vaccination sera.  相似文献   
7.
The aim of the study was to compare the prevalence of cervical muscle pain (CMP) and myogenic temporomandibular disorders (MFP) among female dentists, high‐tech workers, and a group of subjects employed in other occupations; to investigate the associations among CMP, MFP, and bruxism in those groups; and to evaluate the influence of work‐related stress on MFP and CMP. Evaluation was based on clinical examinations of MFP and CMP and self‐reported questionnaires concerning pain and stress. The diagnosis of sleep bruxism was adapted using the validated diagnostic criteria of the American Academy of Sleep Medicine (International Classification of Sleep Disorders (ICSD‐2), 2005, Westchester, IL), whilst the diagnosis of awake bruxism was made on the basis of a questionnaire. The odds of a subject with MFP experiencing concurrent CMP or bruxism (sleep and/or awake) ranged from 2.603 to 3.077. These results suggest that high‐tech workers and dentists are at greater risk for developing temporomandibular disorders (TMDs) and CMP when compared with general occupation workers, as defined in this study. Furthermore, the associations shown here between TMDs and CMP highlight the importance of palpating neck musculature as part of any routine examination of TMD.  相似文献   
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Glutamate toxicity is a major contributor to the pathophysiology of numerous neurodegenerative diseases including amyotrophic lateral sclerosis and Alzheimer’s disease. Therefore, protecting neuronal cells against glutamate-induced cytotoxicity might be an effective approach for the treatment of these diseases. We have previously purified from the medicinal plant Achillea fragrantissima two bioactive compounds which were not studied before: the sesquiterpene lactone achillolide A and the flavonoid 3,5,4′-trihydroxy-6,7,3′-trimethoxyflavone (TTF). We have shown that these compounds protect astrocytes from oxidative stress-induced cell death and inhibit microglial activation. The current study examined for the first time their effects on differentiated mouse neuroblastoma N2a cells and on glutamate toxicity. We have found that, although these compounds belong to different chemical families, they protect neuronal cells from glutamate toxicity. We further demonstrate that this protective effect might be, at least partially, due to inhibitory effects of these compounds on the levels of reactive oxygen species produced following treatment with glutamate.  相似文献   
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