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1.
J Chem Phys ; 136(21): 214314, 2012 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-22697550

RESUMO

We report a combined experimental and theoretical photoelectron spectroscopy study of ZnOH(-). We find that the electron binding energy spectrum of ZnOH(-) reveals a broad and featureless peak between 1.4 and 2.4 eV in energy. The vertical detachment energy (VDE) of ZnOH(-) is determined to be 1.78 eV, which is lower than the 2.08 eV VDE of ZnO(-). Our theoretical calculations match the VDE of ZnOH(-) accurately, but we find that the broadness of the peak cannot be explained by rotational or vibrational state excitation. The broadness of this peak is in strong contrast to the narrow and easily understood first peak of the ZnO spectrum, which features a well-resolved vibrational progression that can be readily explained by calculating the Franck-Condon transition factors. This study provides spectroscopic evidence of the effect of hydrogen on diatomic ZnO.

2.
ACS Nano ; 1(4): 319-26, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19206683

RESUMO

Experimental photoelectron and computational results show diniobium-carbon (Nb(2)C(n)) clusters to coexist in multiple structural isomers: three-dimensional geometries, planar rings, and linear chains. Three-dimensional clusters having up to five carbons are formed preferentially with Nb-Nb bonding, whereas only Nb-C bonding is observed experimentally at six carbons. Clusters consisting of an odd number of atoms are also observed with linear geometries. The larger binary clusters (n > or = 7) display properties similar to those of pure carbon clusters. We provide evidence for niobium substitution of carbon atoms.

3.
J Phys Chem A ; 110(47): 12814-21, 2006 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-17125295

RESUMO

The influence of source conditions on vanadium-carbon cluster formation in a methane-vanadium plasma is explored and analyzed by photoelectron spectroscopy, revealing that the metal-carbon ratio has substantial influence over the cluster products. Experiments that employ large methane content produce carbon-rich mono- and divanadium carbides. The carbon-rich clusters show a preference for the formation of cyclic neutral and linear ionic structures. When the methane concentration is decreased, VmCn clusters are formed with m = 1-4 and n = 2-8. The photoelectron spectra of clusters formed under these conditions are indicative of a three-dimensional network. We have measured a significantly lower vertical electron affinity for the VC2, V2C3, and V4C6 clusters compared with proximate species. Interestingly, the VC2 species is a proposed building block of the M8C12 Met-Car cluster, and the 2,3 and 4,6 clusters correspond to the 1/4 and 1/2 Met-Car cages, respectively. This correlation is taken as evidence of their importance in the formation of the larger Met-Car species. These results are supported by density functional theory (DFT) calculations carried out at the PBE/GGA level.

4.
Khirurgiia (Sofiia) ; (4-5): 64-7, 2006.
Artigo em Búlgaro | MEDLINE | ID: mdl-18843923

RESUMO

We present a case of multiple meningiomas (MM) as initial manifestation of central neurofibromatosis (NF2). A 19 y. o. woman was admitted with increasing signs of spinal cord compression at Th5-7 level. At CT assisted myelography, an entirely extradurally situated meningioma was detected and totally removed. Two years later increasing right-sided exophthalmos, without visual impairment was observed. The CT scan revealed thickening and abnormal shape of the sphenoid and the bony structures of the orbit. The retrobulbar space was narrowed and the optic nerve was shifted. At operation, ala parva of the sphenoid bone, the roof and the lateral orbital wall appeared thickened, laminated, fragile and exceedingly vascularized. The subdural space was found intact. The histopathological study revealed primary intraosseous meningioma of the sphenoid. There was no family history for neurofibromatosis (NF). The clinical findings at this time could not fulfil the criteria for NF2 and the case was considered as "true" multiple meningiomas occurring in different compartments of the neuraxis. The cytogenetical examination demonstrated a deletion of the long arm of the chromosome 22: 46 XX, del 22 (q 11.2). She was followed up and five years after the initial symptoms asymptotic bilateral vestibular schwannomas were found at CT and MRI. These findings finally led to the diagnosis NF2. There are no specific features distinguishing true MM from those associated with NF2, but we recall the importance of such manifestations for this diagnosis. We have not found any comparable case with these features in the medical literature.


Assuntos
Neoplasias Meníngeas , Meningioma , Neurofibromatose 2 , Neoplasias Cranianas , Osso Esfenoide , Adulto , Deleção Cromossômica , Diagnóstico Diferencial , Exoftalmia/diagnóstico , Exoftalmia/etiologia , Feminino , Humanos , Neoplasias Meníngeas/complicações , Neoplasias Meníngeas/diagnóstico , Neoplasias Meníngeas/genética , Neoplasias Meníngeas/cirurgia , Meningioma/complicações , Meningioma/diagnóstico , Meningioma/genética , Meningioma/cirurgia , Neurofibromatose 2/complicações , Neurofibromatose 2/diagnóstico , Neurofibromatose 2/genética , Neurofibromatose 2/cirurgia , Neuroma Acústico/complicações , Neuroma Acústico/diagnóstico , Neuroma Acústico/cirurgia , Doenças do Nervo Óptico/diagnóstico , Doenças do Nervo Óptico/etiologia , Radiografia , Neoplasias Cranianas/complicações , Neoplasias Cranianas/diagnóstico , Neoplasias Cranianas/genética , Neoplasias Cranianas/cirurgia , Osso Esfenoide/diagnóstico por imagem , Osso Esfenoide/patologia
5.
Akush Ginekol (Sofiia) ; 38(1): 46-9, 1999.
Artigo em Búlgaro | MEDLINE | ID: mdl-11965722

RESUMO

Mammographic screening has led to increased detection of intraductal carcinoma of the breast (IdC). IdC is y heterogeneous disorder with different clinical outcomes. The study was designed to confirm consensibility of the three-tiered classification, accepted by Thomas Jefferson University Consensus Conference since 1997. The study population comprised 30 patients with IdC including patients with T1 mic and T1a. Sixty percent of IdC were classified as II-nd grade, 27% were III-rd grade and 13% as I-st grade. 20% of IdC exhibited heterogenity of grade. The cases with cribriform and papillary architecture were 1-st or II-nd grades. The other cases with comedo and solid architecture we are II-nd or III-rd grades. The cases with invasive component (T1 mic u T1a) were 25%--I-st grade, 75%--II-nd grade and III-rd grade--87.5%. In conclusion, the grading of IdC could y prognostic factor in far long term prognosis of patients with those lesions.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Feminino , Humanos
7.
Probl Khig ; 15: 30-8, 1990.
Artigo em Búlgaro | MEDLINE | ID: mdl-2099460

RESUMO

Studies are performed on the new Bulgarian raw materials "Aminookis" (AO) and "Dezodorirashch agent" (DA) the plants "Alen Mak"--Plovdiv and "Hyaluron"--Sofia. Chemical, toxicological and microbiological studies are carried out. Thin-layer chromatographic and spectrophotometric methods for determination of AO, hyaluronic acid and DA are developed and chemical studies on cosmetics, prepared with them, are carried out. During the repetition of a 21-day experiment on guinea pigs the threshold irritative concentrations--10% for AO and DA (as trade products) are determined. This shows that they are moderate contact irritants. The hyaluron has no irritative effect. By maximizing test with guinea pigs is established the absence of contact allergy for DA and AO. At index of sensibilization 10% the hyaluron falls in the group of weak allergens. The spectra of action are studied and the minimum suppressing concentrations of AO and DA are defined. It is established that the most resistant to effect with these cosmetics are the representatives of the families: Pseudomonas, Klebsiella, Escherichia, Salmonella. Recommendations are made to use "Aminookis" (AO) in shampoos to 8%, deodorizing agent in deodorants to 2% and "Hyaluron" in creams to 20% (as trade products).


Assuntos
Cosméticos/toxicidade , Produtos Domésticos/toxicidade , Animais , Bulgária , Cromatografia em Camada Fina , Cosméticos/análise , Desodorantes/análise , Desodorantes/toxicidade , Relação Dose-Resposta a Droga , Cobaias , Produtos Domésticos/análise , Ácido Hialurônico/análise , Ácido Hialurônico/toxicidade , Testes de Sensibilidade Microbiana , Testes Cutâneos , Tensoativos/análise , Tensoativos/toxicidade
8.
Khirurgiia (Sofiia) ; 43(5): 8-16, 1990.
Artigo em Búlgaro | MEDLINE | ID: mdl-2102943

RESUMO

Of 570 patients with clinical manifestations of bile duct and pancreas diseases, examined by ERCP, 122 had different atypical anatomical variants (142 in 114 patients) and anomalies of the biliary passages (8 patients). The incidence of the individual atypical anatomical variants of the bile ducts was, as follows: 1. variants in the entry of the common bile duct in the duodenum--3.3 per cent (19 of 570 patients); 2. variants in the entry of ductus cysticus in the common bile duct--11.1 per cent (63 of 570 patients); 3. variants of the ramifications of the hepatic canals--10.5 per cent (60 of 570 patients). Of the bile duct anomalies, choledochocele was the most common--in 5 of the 8 patients in this group. In addition, there was a double gall bladder, gall bladder atresia and cysts of the intrahepatic bile ducts in one case each. High was the incidence of choledocholithiasis (63 per cent) and especially of primarily formed calculi in the common bile duct (20 per cent), as well as bile duct cancer (11 per cent). Cancer of the biliary passages was significantly commoner in atypical anatomical variants of ductus hepaticus (18 per cent) vs. 8 per cent in atypical variants of ductus cysticus and none in the common bile duct variants (chi 2 = 4.06; p less than 0.05). Cancer of the common bile duct was found also in 1 of the eight patients with anomalies of the biliary passages.


Assuntos
Doenças Biliares/diagnóstico por imagem , Sistema Biliar/anormalidades , Colangiopancreatografia Retrógrada Endoscópica , Pancreatopatias/diagnóstico por imagem , Fatores Etários , Sistema Biliar/diagnóstico por imagem , Doenças Biliares/epidemiologia , Bulgária/epidemiologia , Duodenoscopia , Tecnologia de Fibra Óptica , Humanos , Pancreatopatias/epidemiologia
9.
Akush Ginekol (Sofiia) ; 29(5): 23-7, 1990.
Artigo em Búlgaro | MEDLINE | ID: mdl-2091470

RESUMO

1343 dead children, aged 0-14 years, with undergone autopsies at the chair of pathological anatomy of the Higher Medical Institute in the town of Pleven were studied for a 12-year period (1978-1989). There were 29 cases with congenital diaphragmatic hernia (CDH)--2.16%. 5 out of 19 children had right side CDH--0.37%. The ratio right side/total number of CDH was 1:5.8. This ratio is between 1: to 1:8 according to literary data. The observed cases were: male sex--2, female sex--3; stillborn--1, preterm of 1 degree--3. The shortest survival was 2 hours and 20 minutes, the latest manifested CDH was after 2 hours and months and 15 days. The observed cases were described in details in respect to localization and size of defects, hernial content, clinical course, pathologicoanatomic examination and causes of lethal outcome. The decisive role of roentgenological examination in timely establishment of diagnosis is stressed.


Assuntos
Hérnias Diafragmáticas Congênitas , Bulgária , Causas de Morte , Feminino , Hérnia Diafragmática/mortalidade , Hérnia Diafragmática/patologia , Humanos , Lactente , Recém-Nascido , Pulmão/patologia , Masculino , População Urbana/estatística & dados numéricos
10.
Khirurgiia (Sofiia) ; 43(6): 34-40, 1990.
Artigo em Búlgaro | MEDLINE | ID: mdl-2129348

RESUMO

Of 570 ERHP performed in patients with biliary tract and pancreas diseases, duodenal diverticuli were found in 67 (11.8 per cent). Diverticuli were more frequently diagnosed in patients beyond 60 years of age (67.2 per cent). In 83.6 per cent the diverticuli were single, mostly measuring 15-30 mm and localized in the peripapillary area (70 per cent). ERHP was successful in 85 per cent. Diverticuli were most frequently accompanied by stenosing papillo-odditis (82 per cent), cholecystitis (67 per cent), common bile duct calculosis (58 per cent), followed by pancreatitis (37 per cent) and cancer of the bile ducts (4.5 per cent). Endoscopic treatment was conducted in 46 cases: endoscopic sphincterotomy, hydrostatic balloon dilation of narrowed segments, hydrostatic balloon extraction of calculi, mechanical lithotripsy, nasolabial drainage and endoprosthesis. Significantly lower was the technical success of endoscopic sphincterotomy (78 per cent) when compared with its performance in patients without diverticuli (99 per cent). In spite of this, complex endoscopic treatment resulted in significant fall of bilirubin level (t = 6.58; p less than 0.0001), of AP (t = 8.15; p less than 0.001), of GGJP (t = 6.99; p less than 0.0001), of AcAT (t = 7.14; p less than 0.01). The incidence of complications (6.5 per cent) was not higher than the one observed in patients without diverticuli. In conclusion, endoscopic treatment of bile duct diseases is recommended to be performed also in patients with diverticuli, especially in adult patients and in those exposed to increased operative risk.


Assuntos
Doenças Biliares/cirurgia , Divertículo/cirurgia , Duodenopatias/cirurgia , Duodenoscopia , Pancreatopatias/cirurgia , Idoso , Ampola Hepatopancreática/diagnóstico por imagem , Ampola Hepatopancreática/cirurgia , Doenças Biliares/diagnóstico por imagem , Cateterismo/instrumentação , Cateterismo/métodos , Colangiopancreatografia Retrógrada Endoscópica , Divertículo/diagnóstico por imagem , Duodenopatias/diagnóstico por imagem , Duodenoscópios , Duodenoscopia/métodos , Feminino , Tecnologia de Fibra Óptica/instrumentação , Cálculos Biliares/diagnóstico por imagem , Cálculos Biliares/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Pancreatopatias/diagnóstico por imagem , Radiografia Intervencionista
11.
Vutr Boles ; 28(5): 75-7, 1989.
Artigo em Búlgaro | MEDLINE | ID: mdl-2618012

RESUMO

The acute suppurative cholangitis is an acute emergency condition requiring quick decompression of the obstructed bile pathways. The authors present their experience in the treatment of 51 patients by endoscopic sphincterotomy with or without mechanical lithotripsy and extraction of the stones and a nasobiliary drainage for 5 up to 15 days. Technically the manipulation was 100% successful and its therapeutic efficacy was 94.2% including II patients to whom it was performed as a preoperative procedure. In 6 patients (11.8%) a transitory amylase elevation was registered and one patient (2%) developed acute pancreatitis. The treatment was unsuccessful in 6% of the patients--these were patients with severe liver impairment (biliary cirrhosis) and long term cholangitis. The authors recommend the biliary drainage as an emergency and temporary treatment of the acute suppurative cholangitis.


Assuntos
Sistema Biliar , Colangite/terapia , Doença Aguda , Idoso , Idoso de 80 Anos ou mais , Colelitíase/terapia , Terapia Combinada , Drenagem/instrumentação , Drenagem/métodos , Endoscópios , Endoscopia/métodos , Feminino , Humanos , Litotripsia , Masculino , Pessoa de Meia-Idade , Esfincterotomia Transduodenal/métodos
12.
Vutr Boles ; 28(3): 37-40, 1989.
Artigo em Búlgaro | MEDLINE | ID: mdl-2773458

RESUMO

When there are large stones in the common bile duct or constrictions of the bile ducts the stones very often cannot pas spontaneously or after an endoscopically performed sphincterotomy. In 54 patients after an unsuccessful attempt to extract the stone with the Dormia-basket endoscopic mechanical lithotripsy was performed followed by balloon extraction of the fragments, balloon dilatation of the constricted sectors of the bile duct and securing a bilionasal drainage for prophylaxis of cholangitis. The mechanical lithotripsy was successful in 50 of the patients (92.4%). The jaundice and the cholestasis decreased up to the 10-th day and the cytolytic enzymes became normal. Complications occurred in 2 patients (4%)--hemorrhage up to the 12-th hour after the manipulation. The author recommends, in cases of unsuccessful stone extraction by endoscopic sphincterotomy, the mechanical lithotripsy in combination with balloon extraction of the fragments, balloon dilatation of the constricted sectors of the bile duct and nasobiliary drainage for washing the bile ducts, prevention of bile duct occlusion and treatment of cholangitis in cases of unsuccessful extraction by endoscopic sphincterotomy.


Assuntos
Cálculos Biliares/terapia , Litotripsia/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Cateterismo , Endoscopia , Feminino , Humanos , Litotripsia/efeitos adversos , Litotripsia/instrumentação , Masculino , Pessoa de Meia-Idade , Esfincterotomia Transduodenal
13.
Khirurgiia (Sofiia) ; 42(1): 57-9, 1989.
Artigo em Búlgaro | MEDLINE | ID: mdl-2761182

RESUMO

Two patients with obstructive jaundice are presented. They had cancer of the large duodenal papilla and choledocholithiasis with edema and deformity of the papilla. Endoscopic laser papillosphincterotomy with "Nd-YAG" laser and one-step endoscopic biliary drainage--endoprosthesis of the common bile duct and naso-labial drainage, respectively--were performed. The importance of laser papillotomy in patients, in whom electropapillotomy can not be accomplished or will not give satisfactory results, is emphasized. Analysis is made of the periodic medical literature on this problem. Report is made for the first time on combining two endoscopic methods--laser photocoagulation and endoprosthesis in benign and in malignant stenoses of the papilla, realized in one act.


Assuntos
Ducto Colédoco/cirurgia , Drenagem/métodos , Terapia a Laser/métodos , Esfincterotomia Transduodenal/métodos , Idoso , Colestase/etiologia , Colestase/cirurgia , Drenagem/instrumentação , Duodenoscópios , Duodenoscopia/métodos , Feminino , Tecnologia de Fibra Óptica/instrumentação , Humanos , Terapia a Laser/instrumentação , Masculino , Pessoa de Meia-Idade , Próteses e Implantes , Esfincterotomia Transduodenal/instrumentação
20.
Vet Med Nauki ; 24(4): 71-8, 1987.
Artigo em Búlgaro | MEDLINE | ID: mdl-3629952

RESUMO

Studied was the effect of illumination of varying length and intensity under the industrial raising of broilers. It was found that the use of an illumination programme with an interrupted light regime and low intensity of light affected the live weight, feed intake per unit of produce, and morbidity and mortality rate. The economic effect produced with the introduction of an illumination programme with an interrupted light of low intensity after the first week of BTR-3 regulation consisted in the increase in the production results in the conditions of industrial broiler arising.


Assuntos
Criação de Animais Domésticos/métodos , Galinhas/crescimento & desenvolvimento , Iluminação/métodos , Animais , Bulgária , Fatores de Tempo
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