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51.
In the neck or face, there are different causes for subcutaneous emphysema such as injury to the sinuses, the hypopharynx, the laryngotracheal complex, the pulmonary parenchyma, the esophagus or the presence of gas-forming organisms. However, factitious subcutaneous emphysema, a rare cause, must be considered in the differential diagnosis. In this clinical report, we discuss a 20-year-old girl who was under follow-up because of recurrent subcutaneous emphysema of the face and periorbital area.After 2 years of work-ups, including a period of close observation in the intensive care unit, self air injection by syringe was found as the cause of recurrent subcutaneous emphysema of the face, and the patient was labeled as having factitious recurrent subcutaneous emphysema. Therefore, when a patient presents with unexplained recurrent subcutaneous emphysema, one should suspect self-infliction and examine for puncture marks. 相似文献
52.
Jochen Moll Christian Kexel Hamed Milanchian Mit Balvantray Bhavsar John Howard Barker 《Ultrasound in medicine & biology》2019,45(2):605-611
Approximately 6.3 million fractures occur each year in the United States alone. Accurately monitoring the progression of fracture healing is essential to be able to advise patients when it is safe to return to normal activity. The most common method used to confirm and monitor fracture healing is the acquisition of multiple radiographic images over the many months required for healing. This imaging method uses large expensive equipment and exposes patients to high levels of ionizing radiation. In the study described here, we tested another technology for monitoring fracture healing that could minimize the need for multiple radiographic images. We tested a piezoelectric transducer fixed to the surface of a bone that uses electromechanical impedance spectroscopy to measure simulated fractures and transmits the measurement data to an acoustic receiver located externally on the skin surface. 相似文献
53.
R De Freitas Jr MsM FBSC H Hamed FRCS I Fentiman MD FRCS 《International journal of clinical practice》1992,46(3):187-190
Fine needle aspiration cytology is a safe diagnostic technique for breast cancer and can identify certain benign lesions, which can be excised without affecting surrounding tissue. The combination of experienced operator and cytologist can yield high sensitivity and specificity, together with important prognostic information. 相似文献
54.
Amir Hadi Makan Pourmasoumi Hamed Mohammadi Aftab Javaheri Mohammad Hossein Rouhani 《Phytotherapy research : PTR》2019,33(2):276-287
The effects of pycnogenol on plasma lipids are controversial. A systematic review and meta‐analysis of clinical trials were conducted to obtain a conclusive result in humans. PubMed, Scopus, and Google Scholar were systematically searched until March 2018, to explore the clinical trials that examined the effect of pycnogenol supplementation on lipid parameters among adult human. Methodological quality of the eligible studies was evaluated using the Cochrane Collaboration's tool. To estimate the effect size, changes in blood lipids were implemented. Results were pooled using a random effects model. Potential sources of heterogeneity were explored by subgroup analysis. A systematic review and meta‐analysis of 14 clinical trials with 1,065 participants suggested a significant increase in plasma concentration of high density lipoprotein cholesterol (HDL‐C; 3.27 mg/dL; 95% CI [0.19, 6.36]; p = 0.038). In contrast, plasma levels of total cholesterol (TC; ?4.45 mg/dL, 95% CI [?11.24, 2.34]; p = 0.199), triacylglycerol (TAG; ?3.64 mg/dL; 95% CI [?17.89, 10.61]; p = 0.616), and low density lipoprotein cholesterol (LDL‐C; ?3.61 mg/dl; 95% CI [?8.76, 1.55]; p = 0.171) were not altered. Adjustment for confounding variables was poor in included studies. Also, these studies did not assess dietary lipid intake. The results indicate that pycnogenol supplementation improves levels of HDL‐C; however, the changes in TC, TAG, and LDL‐C were not clinically relevant. Since there are few phytochemicals that have a significant increasing effect on HDL‐C levels, pycnogenol may have important role in prevention of cardiovascular diseases. 相似文献
55.
Perrone A Masullo M Bassarello C Hamed AI Belisario MA Pizza C Piacente S 《Journal of natural products》2007,70(4):584-588
Two new sulfated triterpenes (1, 6) and four new sulfated triterpene glycosides (2-5) have been isolated from the aerial parts of Fagonia arabica. Their structures were established by spectroscopic data analysis. Compounds 1/2 and 3/4 are sulfated derivatives of the rare sapogenins 3beta,27-dihydroxyolean-12-en-28-oic acid and 3beta,27-dihydroxyurs-12-en-28-oic acid, respectively. Compound 5 is an unusual disulfated oleanene derivative characterized by the occurrence of a 13,18-double bond, while compound 6 is the first reported naturally occurring saturated and sulfated pentacyclic triterpene of the taraxastane series with a C-20,28 lactone unit. 相似文献
56.
Breast cancer is the prevalent cancer worldwide. Excessive exposure to endogenous estrogen across a woman's lifespan contributes to and may be a causal factor in breast cancer. Tamoxifen is a mixed estrogen agonist and antagonist, which is used in treatment and prevention of breast cancer as an estrogen antagonist. Many patients experience resistance to tamoxifen for which many mechanisms have been suggested. Endothelin-1 acts as a mitogen for human breast fibroblasts and it affects tumor cell proliferation, invasion, angiogenesis, neovascularization, mitogenesis, and apoptosis inhibition. Previous studies have shown that estradiol is effective in inhibiting endothelin synthesis in breast tissue and cardiovascular system. Tamoxifen as an estrogen receptor (ER) agonist in cardiovascular system has a cardioprotective effect and decreases endothelin level as a vasoconstrictor in cardiovascular system. But in breast tissue tamoxifen acts as an ER antagonist. According to the role of endothelin in breast cancer and inhibitory effect of estrogen on endothelin, we hypothesized that tamoxifen causes increasing in endothelin level or endothelin receptors probably by inhibitory effect on ER in breast tissue, leading to tamoxifen resistance. Therefore a combination of tamoxifen with endothelin antagonist seems to be a reasonable therapeutic strategy. 相似文献
57.
Requirements for the development of IL-4-producing T cells during intestinal nematode infections: what it takes to make a Th2 cell in vivo 总被引:1,自引:0,他引:1
Zhugong Liu Qian Liu John Pesce Robert M. Anthony Erika Lamb Jeannette Whitmire Hossein Hamed Motoko Morimoto Joseph F. Urban Jr William C. Gause 《Immunological reviews》2004,201(1):57-74
Summary: Components of the type 2 immune response may mediate host protection against both helminthic parasites and harmful allergic responses. A central player in this response is the T‐helper 2 (Th2) effector cell, which produces interleukin (IL)‐4, IL‐5, IL‐13, and other Th2 cytokines during the primary and memory response. Specific aspects of the parasite that trigger Th2‐cell differentiation are not yet defined. Furthermore, the cell types and cell surface and secreted molecules that provide the immune milieu required for the development of Th2 effector cells and also Th2 memory cells are not well understood. They will probably vary with the particular helminth or other antigen inducing the Th2 response. We have used third stage larvae of intestinal nematode parasites as adjuvants to promote naïve nonparasite antigen‐specific T cells to differentiate into Th2 cells. This model system avoids possible parasite antigen‐specific T‐cell clones or cross‐reactive memory T cells that may preferentially differentiate into Th2 effector cells during the course of infection and confound the stereotypical components of parasite‐induced Th2 cell differentiation. We have found that these parasites have a potent adjuvant effect and have used our model system to begin to investigate the events that lead to the development of polarized Th2 cells in vivo. 相似文献
58.
Maryam Monajemzadeh Mohammad-Taghi Hagghi-Ashtiani Laleh Montaser-Kouhsari Hamed Ahmadi Heidar Zargoosh Mehdi Kalantari 《Iranian journal of pediatrics.》2011,21(4):485-490
Objective
Acute appendicitis is the most common cause of abdominal surgery in children. Similarity between signs and symptoms of appendicitis and other common pediatric illnesses, atypical manifestations of appendicitis in young children, and children''s inability to give precise explanation for their symptoms contribute to considerable delay in proper diagnosis and increased rate of perforation. Current study reports the surgical and pathological findings of appendectomies in the largest Children''s Hospital in Iran. It also evaluates whether common protocol for pathologic evaluation following appendectomy is beneficial.Methods
Pathologic reports of 947 appendectomies, performed with the presumptive diagnosis of acute appendicitis, were gathered. Correlation between surgical and pathologic findings was assessed. Demographic characteristics of patients between surgical and pathological subgroups were also compared.Findings
The mean age of participants was 6.9±3.5 years. Eighty seven (25.5%) children had abnormal pathological findings and normal surgical report. None of miscellaneous findings including appendicular carcinoid tumor 3 (0.3%), oxyuriasis 2 (0.2%), and mycobacterial infection 4 (0.5%) were recognizable during the surgery. Of all pathologically confirmed cases with perforated appendicitis, 9.7% were not detected during the surgery.Conclusion
In current study, acute appendicitis was the most common pathological diagnosis, however, high normal appendectomy rate along with noticeable proportion of surgically missed perforated appendicitis and unusual histopathologies strongly supported routine histological examination. 相似文献59.
Pasquini G Barba M Hadidi A Faggioli F Negri R Sobol I Tiberini A Caglayan K Mazyad H Anfoka G Ghanim M Zeidan M Czosnek H 《Journal of virological methods》2008,147(1):118-126
Plum pox virus (PPV) is the most damaging viral pathogen of stone fruits. The detection and identification of its strains are therefore of critical importance to plant quarantine and certification programs. Existing methods to screen strains of PPV suffer from significant limitations such as the simultaneous detection and genotyping of several strains of PPV in samples infected with different isolates of the virus. A genomic strategy for PPV screening based on the viral nucleotide sequence was developed to enable the detection and genotyping of the virus from infected plant tissue or biological samples. The basis of this approach is a long 70-mer oligonucleotide DNA microarray capable of simultaneously detecting and genotyping PPV strains. Several 70-mer oligonucleotide probes were specific for the detection and genotyping of individual PPV isolates to their strains. Other probes were specific for the detection and identification of two or three PPV strains. One probe (universal), derived from the genome highly conserved 3' non-translated region, detected all individual strains of PPV. This universal PPV probe, combined with probes specific for each known strain, could be used for new PPV strain discovery. Finally, indirect fluorescent labeling of cDNA with cyanine after cDNA synthesis enhanced the sensitivity of the virus detection without the use of the PCR amplification step. The PPV microarray detected and identified efficiently the PPV strains in PPV-infected peach, apricot and Nicotiana benthamiana leaves. This PPV detection method is versatile, and enables the simultaneous detection of plant pathogens. 相似文献
60.
Phenotyping is commonly used for detection of extended-spectrum beta-lactamase (ESBL) production in gram-negative isolates. ESBLs are mainly coded for by four important genes, namely bla (TEM), bla (SHV), bla (CTX-M), and bla (OXA). Our aim in this study is to assess use of a multiplex PCR as a rapid method to identify four common genes responsible for ESBL production in different gram-negative isolates. All 793 clinical isolates are subjected to both screen and confirmatory testing for ESBL production using double disc synergy testing (DDST). Two hundred isolates with the ESBL phenotype are subjected to multiplex PCR for detection of the four genes bla (TEM, SHV, CTX-M, and OXA). The isolates were obtained from various clinical specimens: 68 (34 %) were isolated from urine cultures, 43 (21.5 %) from sputum, 26 (13 %) from wounds, 34 (17 %) from blood culture, 20 (10 %) from stool of healthy carrier and nine (4.5 %) from bronchoalveolar lavages. In this study, 83 isolates (41.5 %) were from outpatients (urine and stool specimens only), and the remaining 117 isolates (58.5) were from inpatients. By PCR technique, 181 isolates were found to be ESBL producers. blaTEM was the commonest genotype (39.2 %), followed by blaSHV (32.5 %) and blaCTX-M (30.9 %), either alone or in combination. Acinetobacter baumannii isolate had none of the ESBL genes. Eighteen (9.9 %) out of 181 isolates carried more than one type of beta-lactamase genes. Our study demonstrated rapid detection of bla (TEM, SHV, CTX-M, and OXA) in isolates belonging to Enterobacteriaceae and other nonfermenting clinical isolates using multiplex PCR. This genotypic method provided a rapid and efficient differentiation of ESBLs in the laboratory. 相似文献