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1.
Zhonghua Jie He He Hu Xi Za Zhi ; 46(8): 824-828, 2023 Aug 12.
Artigo em Zh | MEDLINE | ID: mdl-37536995

RESUMO

Bronchial asthma is a common chronic inflammatory airway disease. Small airway dysfunction (SAD) can be present in asthmatics with different phenotypes, clinical stages and varied severity, and has implication for drug efficacy and patient prognosis. Currently, there is no consensus on the criteria for SAD, and its inflammatory mechanism remains unclear. In this paper, we reviewed the research advances in the evaluation, prevalence, pathogenesis, clinical features and treatment of SAD in asthmatics to improve awareness of the disease.


Assuntos
Asma , Doença Pulmonar Obstrutiva Crônica , Humanos , Asma/tratamento farmacológico , Doença Crônica , Fenótipo
2.
Zhonghua Yu Fang Yi Xue Za Zhi ; 55(12): 1410-1418, 2021 Dec 06.
Artigo em Zh | MEDLINE | ID: mdl-34963237

RESUMO

Objective: To explore the distribution characteristics of pathogens in adult patients with community-acquired pneumonia (CAP) and to provide basis for the diagnosis, treatment, prevention of CAP. Methods: 1 446 inpatients with CAP were prospectively enrolled in a third-class hospital in Beijing in recent 5 years (from January 2015 to December 2019). Respiratory tract samples were collected for smear, culture, nucleic acid, antigen and antibody detection to identify the pathogen of CAP. Mann-Whitney U test was used for continuous variables and χ2 test or Fisher's exact test was used for categorical data for statistical analysis. Results: Among the 1 446 patients, 822 (56.85%) patients were infected with a single pathogen, 231 (15.98%) patients were infected with multiple pathogens, and 393 (27.18%) patients were not clear about the pathogen. Influenza virus is the first pathogen of CAP (20.95%, 303/1 446), mainly H1N1 (8.51%, 123/1 446), followed by mycoplasma pneumoniae (7.19%, 104/1 446), Mycobacterium tuberculosis (5.33%, 77/1 446) and Streptococcus pneumoniae (5.05%, 73/1 446). The outbreak of H1N1 occurred from December 2018 to February 2019, and the epidemic of mycoplasma pneumoniae pneumonia was monitored from August to November 2019. Patients under 65 years old had high detection rates of Mycoplasma pneumoniae (14.41% vs. 2.41%, χ²=74.712,P<0.001), Streptococcus pneumoniae (8.16% vs. 2.99%, χ²=18.156, P<0.001), rhinovirus (6.08% vs. 3.56%, χ²=5.025, P<0.025), Chlamydia pneumoniae (5.90% vs. 1.15%, χ²=26.542, P<0.001) and adenovirus (3.13% vs. 0.92%, χ²=9.547, P=0.002). The severe disease rate of CAP was 14.66% (212/1 446), and the average mortality rate was 3.66% (53/1 446). The severe illness rate and mortality rate of bacterial-viral co-infection were 28.97% (31/107) and 19.63% (21/107), respectively. Conclusions: Influenza virus is the primary pathogen of adult CAP. Outbreaks of Mycoplasma pneumoniae and H1N1 were detected in 2018 and 2019, respectively. The remission rate and mortality rate of virus-bacteria co-infection were significantly higher than those of single pathogen infection. Accurate etiological basis not only plays a role in clinical diagnosis and treatment, but also provides important data support for prevention and early warning.


Assuntos
Chlamydophila pneumoniae , Infecções Comunitárias Adquiridas , Vírus da Influenza A Subtipo H1N1 , Pneumonia por Mycoplasma , Adulto , Idoso , Infecções Comunitárias Adquiridas/prevenção & controle , Hospitais , Humanos , Pneumonia por Mycoplasma/epidemiologia , Pneumonia por Mycoplasma/prevenção & controle
3.
Zhonghua Jie He He Hu Xi Za Zhi ; 44(2): 88-95, 2021 Feb 12.
Artigo em Zh | MEDLINE | ID: mdl-33535322

RESUMO

Objective: To study the clinical and etiological characteristics of viral pneumonia in patients with chronic obstructive pulmonary disease(VP-COPD), and to identify the risk factors associated with poor prognosis. Methods: From August 1, 2017 to August 1, 2019, totally 235 patients in a general hospital in Beijing were prospectively enrolled in this research, and all patients were diagnosed with viral pneumonia by imaging and etiology. The patients were divided into VP-COPD group(n=60) and VP-nCOPD(viral pneumonia in non-COPD patients) group(n=175). Pathogen detection and clinical characteristics were compared between the two groups.Finally, the binomial logistic regression was used to explore the risk factors associated with severe VP-COPD. Results: Compared with the VP-nCOPD group, the VP-COPD group was older(76.5 vs 66.0 years, P=0.001), and the CURB-65 score(2 vs 1, P= 0.001) and the PSI score(111 vs 85, P<0.001) were higher at admission. Pseudomonas aeruginosa(χ²= 10.308, P= 0.001) and Staphylococcus aureus(χ²= 5.953, P=0.028) were the most common co-infection bacteria. In the VP-COPD group type Ⅱ respiratory failure was more common(23.3% vs 6.8%, P<0.001), the number of severely ill patients was larger(48.3% vs 30.3%, P=0.011), the length of hospital stay was longer(13 vs 8, P<0.001), and the mortality rate during hospitalization was higher(18.3% vs 7.4%, P=0.016) in the VP-nCOPD group. Multivariate analysis showed that the level of blood glucose(OR: 1.73, 95%CI: 1.22-2.44, P= 0.002) and pleural effusion(OR: 133.12, 95%CI: 7.57-2 340.36, P=0.001) were risk factors for severe VP-COPD patients. Conclusion: Viral pneumonia in patients with COPD tended to develop into severe cases and had a poor prognosis.


Assuntos
Pneumonia Viral/etiologia , Doença Pulmonar Obstrutiva Crônica/complicações , Idoso , China/epidemiologia , Coinfecção , Feminino , Humanos , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , Pneumonia Viral/terapia , Prognóstico , Infecções por Pseudomonas/epidemiologia , Pseudomonas aeruginosa/isolamento & purificação , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Doença Pulmonar Obstrutiva Crônica/terapia , Respiração Artificial/estatística & dados numéricos , Insuficiência Respiratória , Estudos Retrospectivos , Fatores de Risco , Infecções Estafilocócicas/epidemiologia , Staphylococcus aureus/isolamento & purificação
4.
Zhonghua Jie He He Hu Xi Za Zhi ; 40(1): 52-57, 2017 Jan 12.
Artigo em Zh | MEDLINE | ID: mdl-28100363

RESUMO

Objective: To describe the clinical features of hyper-IgE syndrome (HIES), with emphasis on refractory pulmonary cystic lesions as the initial presentation in adulthood. Methods: A case of HIES presenting with pulmonary cystic lesions in an adult patient was retrospectively analyzed. We used "hyper-IgE syndrome" as the Chinese keywords, "hyper-IgE syndrome, China" as the English keywords to retrieve the literature from Wanfang database/CNKI database and Pubmed database until April 2016. The clinical data were pooled and analyzed. Results: A 19 year old female patient was admitted to our hospital because of recurrent cough and expectoration as the chief complaint. Physical examination revealed broad nasal bridge and scoliosis, and chest CT showed gradually enlarged and increased cystic lesions. Laboratory studies demonstrated significantly increased blood eosinophils and serum level of total IgE, together with a definite chemotactic dysfunction of neutrophils. A further detection of STAT3 mutation was negative. The diagnosis of HIES was made and antibiotic treatment resulted in disease remission. Literature review found 45 reports including 37 in Chinese and 11 in English. Eight cases of adult HIES were reported, and all the patients were male, aging 18 to 31 years. Prolonged disease course, recurrent infection and formation of cystic lesions in the lungs were important features of HIES. Early diagnosis and treatment with specific antibiotics were important for improving outcome of the patients. Conclusion: Refractory pulmonary cystic lesions can be the initial presentation in adult HIES. Understanding of the clinical characteristics of HIES will be helpful to avoid misdiagnosis and improve prognosis.


Assuntos
Imunoglobulina E/sangue , Síndrome de Job/diagnóstico , Neutrófilos/patologia , Adulto , Antibacterianos/uso terapêutico , China , Feminino , Humanos , Síndrome de Job/tratamento farmacológico , Masculino , Mutação , Estudos Retrospectivos , Fator de Transcrição STAT3 , Resultado do Tratamento
5.
Phys Med Biol ; 48(5): 633-51, 2003 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-12696800

RESUMO

A hybrid proportional-integral-in-time and cost-minimizing-in-space feedback control system for electromagnetic, deep regional hyperthermia is proposed. The unique features of this controller are that (1) it uses temperature, not specific absorption rate, as the criterion for selecting the relative phases and amplitudes with which to drive the electromagnetic phased-array used for hyperthermia and (2) it requires on-line computations that are all deterministic in duration. The former feature, in addition to optimizing the treatment directly on the basis of a clinically relevant quantity, also allows the controller to sense and react to time- and temperature-dependent changes in local blood perfusion rates and other factors that can significantly impact the temperature distribution quality of the delivered treatment. The latter feature makes it feasible to implement the scheme on-line in a real-time feedback control loop. This is in sharp contrast to other temperature optimization techniques proposed in the literature that generally involve an iterative approximation that cannot be guaranteed to terminate in a fixed amount of computational time. An example of its application is presented to illustrate the properties and demonstrate the capability of the controller to sense and compensate for local, time-dependent changes in blood perfusion rates.


Assuntos
Campos Eletromagnéticos , Hipertermia Induzida/instrumentação , Hipertermia Induzida/métodos , Modelos Biológicos , Neoplasias/terapia , Temperatura Corporal/efeitos da radiação , Regulação da Temperatura Corporal , Simulação por Computador , Desenho de Equipamento , Retroalimentação , Temperatura Alta/uso terapêutico , Humanos , Neoplasias/fisiopatologia , Controle de Qualidade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Temperatura , Terapia Assistida por Computador/instrumentação , Terapia Assistida por Computador/métodos
6.
Phys Med Biol ; 41(12): 2719-38, 1996 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8971965

RESUMO

A numerical method is presented to compute electromagnetic fields inside a 2 mm high resolution, anatomically detailed model of a human head for high-frequency magnetic resonance imaging (MRI) applications. The method uses the biconjugate gradient algorithm in combination with the fast Fourier transform to solve a matrix equation resulting from the discretization of an integrodifferential equation representing the original physical problem. Given the current distribution in an MRI coil, the method can compute both the electric field (thus the specific energy absorption rate (SAR)) and the magnetic field, also known as the B1 field. Results for the SAR and B1 field distribution, excited by a linear and a quadrature birdcage coil, are calculated and presented at 64 MHz, 128 MHz and 256 MHz, corresponding to the operating frequencies of the 1.5 T, 3 T and 6 T MRI systems. It is shown that compared with that at 64 MHz, the SAR at 128 MHz is increased by a factor over 5 and the SAR at 256 MHz is increased by a factor over 10, assuming the same current strength in the coil. Furthermore, compared with the linear excitation, the average SAR for the quadrature excitation is reduced by a factor over 2 and the maximum SAR is reduced by a factor over 3. It is also shown that the B1 field at high frequencies exhibits a strong inhomogeneity, which is attributed to dielectric resonance.


Assuntos
Campos Eletromagnéticos , Imageamento por Ressonância Magnética , Modelos Teóricos , Imagens de Fantasmas , Algoritmos , Análise de Fourier , Cabeça , Humanos
7.
IEEE Trans Biomed Eng ; 46(11): 1387-90, 1999 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-10582424

RESUMO

A fast frequency-sweep technique is developed for the analysis of radio-frequency coils for magnetic resonance imaging. This technique applies the method of asymptotic waveform evaluation to the moment method solution of the integral equation for the original physical problem. Numerical examples show that the proposed technique can speed up the analysis by more than an order of magnitude.


Assuntos
Imageamento por Ressonância Magnética/instrumentação , Desenho de Equipamento/estatística & dados numéricos , Imageamento por Ressonância Magnética/métodos , Imageamento por Ressonância Magnética/estatística & dados numéricos , Matemática , Ondas de Rádio
8.
IEEE Trans Biomed Eng ; 47(11): 1525-33, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11077747

RESUMO

A method of computing the signal-to-noise ratio (SNR) in high-frequency magnetic resonance (MR) imaging systems is presented. The method uses a numerical solution to Maxwell's equations which can capture all relevant electrodynamic effects at high B0-field strengths. Using this method, the intrinsic SNR of both volume and surface coils loaded with the human head is calculated as a function of frequency. It is shown that although the available SNR from any point scales favorably with frequency, phase inhomogeneity over the volume of the head may pose a challenge to achieving improved SNR with traditional imaging techniques at high B0-field strengths.


Assuntos
Imageamento por Ressonância Magnética/estatística & dados numéricos , Engenharia Biomédica , Biometria , Cabeça/anatomia & histologia , Humanos , Modelos Anatômicos , Processamento de Sinais Assistido por Computador
9.
IEEE Trans Biomed Eng ; 45(5): 650-9, 1998 May.
Artigo em Inglês | MEDLINE | ID: mdl-9581064

RESUMO

The finite-difference time-domain (FDTD) method is combined with the method of moments (MoM) to compute the electromagnetic fields of shielded radio-frequency (RF) coils loaded with an anatomically accurate model of a human head for high-frequency magnetic resonance imaging (MRI) applications. The combined method can predict both the specific energy absorption rate (SAR) and the magnetic field (known as the B1 field) excited by any RF coils. Results for SAR and B1 field distribution, excited by shielded and end-capped birdcage coils, are calculated at 64, 128, 171, and 256 MHz. The results show that the value of SAR increases when the frequency of the B1 field increases and the B1 field exhibits a strong inhomogeneity at high frequencies.


Assuntos
Campos Eletromagnéticos , Cabeça/anatomia & histologia , Imageamento por Ressonância Magnética , Modelos Biológicos , Algoritmos , Simulação por Computador , Condutividade Elétrica , Humanos , Valores de Referência , Propriedades de Superfície
10.
Chin Med J (Engl) ; 105(12): 1014-9, 1992 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1299549

RESUMO

In 18 dogs ischemic left ventricular failure characterized by a 30 percent reduction in peak rate of rise of left ventricular pressure (+dp/dt) and elevation of left ventricular end-diastolic pressure (LVEDP) to 15 mmHg or more was produced by ligation of the proximal left anterior descending coronary artery followed by serial occlusions of the distal left circumflex coronary artery. In 10 days, administration of berberine in an intravenous bolus injection (1 mg/kg, within 3 minutes) followed by a constant infusion (0.2 mg/kg/min, 30 minutes) increased the cardiac output (CO) from 1.25 +/- 0.12 to 1.61 +/- 0.17 L/min (P < 0.05), and +dp/dt from 810 +/- 85 to 1021 +/- 130 mmHg/s (P < 0.01), and decreased LVEDP from 16.5 +/- 1.3 to 12.0 +/- 1.0 mmHg (P < 0.05), diastolic blood pressure from 94 +/- 6 to 84 +/- 5 mmHg (P < 0.01), systemic vascular resistance from 7303 +/- 278 to 5442 +/- 231 dynes.x/cm5 (P < 0.01), but did not affect the heart rate. Injection of 5% glucose with the same volume did not improve CO and dp/dt (P > 0.05) but increased the LVEDP from 17.1 +/- 1.4 to 17.8 +/- 1.6 mmHg (P < 0.01) in 8 dogs. The levels of plasma concentration of berberine was determined with high-performance liquid chromatography. The changes in plasma drug level were found parallel to hemodynamic effects of berberine. The results of this study showed that berberine was able to improve the impaired left ventricular function by its positive inotropic effect and mild systemic vasodilatation.


Assuntos
Berberina/farmacologia , Baixo Débito Cardíaco/fisiopatologia , Hemodinâmica/efeitos dos fármacos , Animais , Berberina/sangue , Berberina/uso terapêutico , Baixo Débito Cardíaco/tratamento farmacológico , Cães , Feminino , Masculino , Isquemia Miocárdica/fisiopatologia , Estimulação Química
11.
Zhonghua Nei Ke Za Zhi ; 28(12): 737-40, 769, 1989 Dec.
Artigo em Zh | MEDLINE | ID: mdl-2636093

RESUMO

Bone marrow cells from 33 patients with AML were cultured in vitro using PHA-LCM. The test consisted of two phases: an initial liquid phase and then a semi-liquid phase as described by Dicke et al. Drug sensitivity test for homoharringtonine (H) and cytarabine (A) were performed with clonogenic assay. All patients were treated with these drugs. The results showed that PHA-induced leukemic colonies (CFU-AML) varied from 0 to 812/2 x 10(5) cells (median 175). Three patterns of cell growth were recognized in analysis: high degree (7 patients) with more than 250 CFU-AML colonies, median degree (17 patients) with 50-250 and low, degree with 0 to 49 colonies (9 patients). Drug sensitivity was closely related to the cell growth patterns as evaluated with the clinical outcome. Patients with "high" growth pattern needed more sensitive drugs. When clonogenic assay showed "low" growth pattern, all patients responded to H and A very well regardless the degree of drug sensitivity. Most patients with M3 had high or median growth patterns and relatively low sensitivity to HA. Only one of the six patients with M3 got remission.


Assuntos
Alcaloides/farmacologia , Ensaio de Unidades Formadoras de Colônias , Citarabina/farmacologia , Harringtoninas/farmacologia , Leucemia Mieloide Aguda/patologia , Ensaio Tumoral de Célula-Tronco , Medula Óssea/patologia , Ensaio de Unidades Formadoras de Colônias/métodos , Mepesuccinato de Omacetaxina , Humanos , Prognóstico , Ensaio Tumoral de Célula-Tronco/métodos
12.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 12(5): 285-7, 261-2, 1992 May.
Artigo em Zh | MEDLINE | ID: mdl-1392481

RESUMO

Ginseng was said to be benefit for anemia in TCM. Proliferation effects of total saponins of panax ginseng (TSPG) on hematopoietic progenitor cell in normal individuals and 29 patients with aplastic anemia (AA) were observed by bone marrow culture of BFU-E, CFU-E, CFU-GM in vitro compared with methyltestosterone (MT). The results showed that TSPG might prompt proliferation of normal progenitor cells at the concentration of 20 micrograms/ml. The number of BFU-E, CFU-E and CFU-GM had increased by 37.8 +/- 2.9%, 31.4 +/- 2.9% and 33.3 +/- 4.0% over the controls respectively; furthermore TSPG was still useful to BFU-E, CFU-E growth without Epo in vitro, although the colony numbers were very lower. Otherwise MT was useless to CFU-GM. 14 of the 29 patients with AA who responded to MT showed sensitivity to TSPG in marrow culture (the rising rate of colony formation exceeded 30%), but immune-mediated AA (patient's PBMNC suppressed normal hematopoiesis) and stem cell-decreased AA (few of colony was formed) showed almost no expression for TSPG activity because of immunological suppression system and absence of progenitors.


Assuntos
Anemia Aplástica/patologia , Células-Tronco Hematopoéticas/efeitos dos fármacos , Saponinas/farmacologia , Adolescente , Adulto , Medula Óssea/patologia , Células da Medula Óssea , Células Cultivadas , Criança , Ensaio de Unidades Formadoras de Colônias , Células Precursoras Eritroides/efeitos dos fármacos , Feminino , Ginsenosídeos , Células-Tronco Hematopoéticas/citologia , Células-Tronco Hematopoéticas/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Testosterona/farmacologia
14.
Phys Chem Chem Phys ; 10(25): 3774-83, 2008 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-18563238

RESUMO

The dynamics of adsorption and oxidation of CO on Ru(0001) electrode in sulfuric acid solution have been studied using in situ FTIR spectroscopy under potential control and at open circuit, the latter at 20 and 55 degrees C. The in situ IR data show clearly that the bisulfate anion adsorbs on the Ru(0001) surface over the potential range from -200 mV to 350 mV (vs. Ag/AgCl) at 20 degrees C in the absence and presence of adsorbed CO; however, increasing the temperature to 55 degrees C and/or increasing the concentration of dissolved O(2) reduces the bisulfate adsorption. The formation of surface (hydro-) oxide at higher potentials replaces the bisulfate adsorbates. Both linear (CO(L)) and three-fold hollow bonded CO (CO(H)) adsorbates were produced following CO adsorption at Ru(0001) in H(2)SO(4), as was observed in our previous studies in HClO(4). However, the amount of adsorbed CO observed in H(2)SO(4) was ca. 10% less than that in HClO(4); in addition, the CO(L) and CO(H) frequencies were higher in H(2)SO(4), and the onset potential for CO(ads) oxidation 25 mV lower. These new results are interpreted in terms of a model in which the adsorbed bisulfate weakens the CO adlayer, allowing the active Ru oxide layer to form at lower potentials. Significantly different results were observed at open circuit in H(2)SO(4) compared both to the data under potential control and to our earlier data in HClO(4), and these observations were rationalized in terms of the adsorbed HSO(4)(-) anions (pre-adsorbed at -200 mV) inhibiting the oxidation of the surface at open circuit (after stepping from the initial potential of -200 mV), as the latter was no longer driven by the imposed electrochemical potential but via chemical oxidation by trace dissolved O(2). Results from experiments at open circuit at 55 degrees C and using oxygen-saturated H(2)SO(4) supported this model. The difference in Ru surface chemistry between imposed electrochemical control and chemical control has potential implications with respect to fuel cell electrocatalysis.


Assuntos
Ânions/química , Monóxido de Carbono/química , Adsorção , Catálise , Fontes de Energia Elétrica , Eletroquímica , Eletrodos , Modelos Químicos , Oxirredução , Rutênio/química , Espectroscopia de Infravermelho com Transformada de Fourier , Sulfatos/química , Ácidos Sulfúricos/química , Propriedades de Superfície , Temperatura
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