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101.
Short acting nitrates are commonly used to prevent the anginal pain. The purpose of the study was to compare antianginal efficacy of Pentaerythritol compositum (20 mg of pentaerythritol tetranitrate and 0.5 mg of nitroglicerine) and 0,5 mg of nitroglycerine. Twenty patients aged 45-75 years with stable angina were enrolled. Antianginal effectiveness was evaluated during treadmill test. Time to ischemic pain and/or electrocardiographic parameters of ischemia were measured. It was found that Pentaerythritol compositum was superior to nitroglycerine in preventing angina with the difference disappearing 60 minutes after drug administration. Both drugs were well tolerated. Achieved results show that Pentaerythritol compositum can be effective as antianginal drug in patients with stable angina.  相似文献   
102.
Context: The Caucasian giant hogweeds (Heracleum sosnowskyi and H. mantegazzianum) are aggressive invaders successfully spreading across different parts of Europe. Their sap containing linear furanocoumarins can lead to a persisting cutaneous dermatitis and massive skin necrosis.

Objective: We aimed to assess the awareness of the giant hogweeds’ threat among physicians and general public in Poland.

Methods: The level of awareness was assessed using a short questionnaire given to different groups of physicians: dermatologists (DMs), general practitioners (GPs) and occupational practitioners (OPs). An independent questionnaire was also addressed to the general public.

Results: Among the surveyed physician groups, DMs were the best informed, while OPs were the worst informed on health threats associated with the giant hogweeds and treatment methods. Most frequently, application of topical corticosteroids was indicated as a successful method of treatment following the exposure to hogweeds. In the general public, awareness was relatively low with only 57.7% of the surveyed having ever heard about these plants. TV, press and Internet were among the most frequent sources of information in this regard.

Conclusions: Public and medical attention needs to be raised as to the threats associated with giant hogweeds, particularly in countries that are highly infested with these plants.  相似文献   

103.
OBJECTIVES: The goal of this study was to describe the mapping and ablation of polymorphic ventricular tachycardia (VT) after myocardial infarction (MI). BACKGROUND: The initiating mechanisms of polymorphic VT after MI have not been reported. METHODS: Five patients (four males; age 61 +/- 7 years) with recurrent episodes of polymorphic VT after anterior MI (left ventricular ejection fraction 32 +/- 7%) despite revascularization and antiarrhythmic drugs were studied. All patients demonstrated frequent ventricular premature beats (PBs) initiating polymorphic VT. Pace mapping and activation mapping were used to identify the earliest site of PB activity. The presence of a Purkinje potential preceding PB defined its origin from the Purkinje network. Electroanatomic voltage mapping was performed to delineate the extent of MI. RESULTS: The PBs were observed in all cases to arise from the Purkinje arborization in the MI border zone. These PBs were right bundle-branch block in all five patients, with morphologic variations in the limb leads in four; one also had a left bundle-branch block morphology. The coupling interval of the PB to the preceding QRS complex demonstrated significant variations (320 to 600 ms). During PB, the Purkinje potential at the same site preceded the QRS complex by 20 to 160 ms and was associated with different morphologies. Repetitive Purkinje activity was documented during polymorphic VT. Splitting of Purkinje activity and Purkinje to muscle conduction block were also observed. Ablation at these sites eliminated all PBs. At 16 +/- 5 months follow-up using defibrillator memory interrogation, no patient has had recurrence of arrhythmia. CONCLUSIONS: The Purkinje arborization along the border-zone of scar has an important role in the mechanism of polymorphic VT in patients after MI. Ablation of the local Purkinje network allows suppression of polymorphic VT.  相似文献   
104.
Somatic mosaicism for DNA copy‐number alterations (SMC‐CNAs) is defined as gain or loss of chromosomal segments in somatic cells within a single organism. As cells harboring SMC‐CNAs can undergo clonal expansion, it has been proposed that SMC‐CNAs may contribute to the predisposition of these cells to genetic disease including cancer. Herein, the gross genomic alterations (>500 kbp) were characterized in uninvolved mammary glandular tissue from 59 breast cancer patients and matched samples of primary tumors and lymph node metastases. Array‐based comparative genomic hybridization showed 10% (6/59) of patients harbored one to 359 large SMC‐CNAs (mean: 1,328 kbp; median: 961 kbp) in a substantial portion of glandular tissue cells, distal from the primary tumor site. SMC‐CNAs were partially recurrent in tumors, albeit with considerable contribution of stochastic SMC‐CNAs indicating genomic destabilization. Targeted resequencing of 301 known predisposition and somatic driver loci revealed mutations and rare variants in genes related to maintenance of genomic integrity: BRCA1 (p.Gln1756Profs*74, p.Arg504Cys), BRCA2 (p.Asn3124Ile), NCOR1 (p.Pro1570Glnfs*45), PALB2 (p.Ser500Pro), and TP53 (p.Arg306*). Co‐occurrence of gross SMC‐CNAs along with point mutations or rare variants in genes responsible for safeguarding genomic integrity highlights the temporal and spatial neoplastic potential of uninvolved glandular tissue in breast cancer patients.  相似文献   
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Pulmonary embolism onset is frequently neglected due to the non-specific character of its symptoms. Pocket-size imaging devices (PSID) present an opportunity to implement imaging diagnostics into conventional physical examination. The aim of this study was to test the hypothesis that supplementation of the initial bedside assessment of patients with suspected pulmonary embolism (PE) with four-point compression venous ultrasonography (CUS) and right ventricular size assessment with the use of PSID equipped with dual probe could positively influence the accuracy of clinical predictions. A single-centre, prospective analysis was conducted on 100 patients (47 men, mean age 68?±?13 years) with suspected PE. Clinical assessment on the basis of Wells and revised Geneva score and physical examination were supplemented with CUS and RV measurements by PSID. The mean time of PSID scanning was 4.9?±?0.8 min and was universally accepted by the patients. Fifteen patients had deep venous thrombosis and RV enlargement was observed in 59 patients. PE was confirmed in 24 patients. If the both CUS was positive and RV enlarged, the specificity was 100% and sensitivity 54%, ROC AUC 0.771 [95% CI 0.68–0.85]. The Wells rule within our study population had the specificity of 86% and sensitivity of 67%, ROC AUC 0.776 (95% CI 0.681–0.853, p?<?0.0001). Similar values calculated for the revised Geneva score were as follows: specificity 58% and sensitivity 63%, ROC AUC 0.664 (95% CI 0.563–0.756, p?=?0.0104). Supplementing the revised Geneva score with additional criteria of CUS result and RV measurement resulted in significant improvement of diagnostic accuracy. The difference between ROC AUCs was 0.199 (95% Cl 0.0893–0.308, p?=?0.0004). Similar modification of Wells score increased ROC AUC by 0.133 (95% CI 0.0443–0.223, p?=?0.0034). Despite the well-acknowledged role of the PE clinical risk assessment scores the diagnostic process may benefit from the addition of basic bedside ultrasonographic techniques.  相似文献   
107.
Modification of ultrasmall gold nanoparticles (AuNPs) with the lipoic acid derivative of folic acid was found to enhance their accumulation in the cancer cell, as compared to AuNPs without addressing units. The application of lipoic acid enabled the control of the gold nanoparticle functionalities leading to enhanced solubility and allowing for attachment of both the folic acid and the cytotoxic drug, doxorubicin. More robust attachment of doxorubicin to the nanoparticle through the amide bond resulted in toxicity comparable with that of the drug alone, opening a new perspective for designing more potent, but less toxic nanopharmaceuticals. The increased uptake was accompanied by pronounced nuclear accumulation and observable cytotoxicity. Doxorubicin binding via covalent amide bonds enhanced stability of the whole drug vehicle and provided much better control over doxorubicin release in the cell environment, as compared to physical adsorption or pH sensitive bonding commonly used for anthracycline carriers. Confocal microscopy revealed that the bond was stable in the cytoplasm for 22 h. The ability to slow down the rate of drug release may be crucial for the application in sustained anticancer drug delivery. Biological analyses performed using MTT assay and confocal microscopy confirmed that the ultrasmall AuNPs with the lipoic acid derivative of folic acid exhibit relatively low cytotoxicity, however when loaded with a chemotherapeutic, they cause a significant reduction in the cell viability.

Modification of ultrasmall gold nanoparticles (AuNPs) with the lipoic acid derivative of folic acid was found to enhance their accumulation in the cancer cell, as compared to AuNPs without addressing units.  相似文献   
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110.
In this work we propose a completely new approach for the synthesis of spirochlorin derivatives based on the use of an imino-keto intermediate formed in situ from 2-amino-5,10,15,20-tetraphenylporphyrins and inverse electron demand Diels–Alder (iEDDA) cycloaddition with 3,6-di-2-pyridyl-1,2,4,5-tetrazine. The mechanism of reaction was analyzed employing theoretical methods by comparing the difference in energy of Frontier Molecular Orbitals (FMO) for appropriate reagents. Ground-state molecular electrostatic (ESP) potential maps were employed as additional tools allowing explanation of the reactivity of substrates. The new class of spirochlorin compounds was fully characterized by means of mass spectrometry, IR, liquid and solid state NMR and X-ray crystallography. Correlation between molecular structure and optical properties for the obtained title compounds is discussed.

Oxospirochlorins – novel analogs of porphyrinoids were synthesized and characterized by various methods including X-ray, NMR spectroscopy and mass spectrometry.  相似文献   
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