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71.
DNA sequencing is the gold standard method for accurate microbial and viral typing. However, DNA sequencing techniques have been facing limitations in typing of human papillomaviruses when the specimen harbors multiple genotypes and yields nonspecific amplification products, resulting in nonspecific and noninterpretable sequence data. To address these limitations we have developed a type-specific multiple sequencing primer DNA-sequencing method. This new strategy is suitable for sequencing and typing of samples harboring different genotypes (co-infections with multiple genotypes) and yielding nonspecific amplifications, thus eliminating the need for nested polymerase chain reaction (PCR), stringent PCR conditions, and cloning. The new approach has also proved useful for amplicons containing low PCR yield or subdominant types, avoiding reperforming of amplifications. We have applied the multiple sequencing primer method for genotyping of clinically relevant human papillomaviruses in a clinical test panel by using a combined pool of seven type-specific sequencing primers for HPV-6, -11, -16, -18, -31, -33, and -45. Furthermore, we introduced a sequence pattern recognition approach when there was a plurality of genotypes in the sample to facilitate typing of more than one target DNA in the sample. The multiple sequencing primer method has proved to be a multifaceted approach for typing of human papillomaviruses by DNA sequencing technologies.  相似文献   
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73.
The coumarin compounds are an important class of biologically active molecules, which have attractive caught the attention of many organic and medicinal chemists, due to potential pharmaceutical implications and industrial applications. We herein report the one‐pot procedure for the efficient synthesis of coumarin derivatives using commercially available substrates via isocyanide‐based multicomponent condensation reactions. These compounds were evaluated for anti‐mycobacterium activity against Mycobacterium bovis (Bacillus Calmette–Guerin). The preliminary results indicated that all of the tested compounds showed relatively good activity against the test organism. The compounds 7e , 7l , and 7m showed high anti‐tuberculosis activity.  相似文献   
74.

Background  

Work-site strength training sessions are shown effective to prevent and reduce neck-shoulder pain in computer workers, but difficult to integrate in normal working routines. A solution for avoiding neck-shoulder pain during computer work may be to implement high intensity voluntary contractions during the computer work. However, it is unknown how this may influence productivity, rate of perceived exertion (RPE) as well as activity and rest of neck-shoulder muscles during computer work. The aim of this study was to investigate short-term effects of a high intensity contraction on productivity, RPE and upper trapezius activity and rest during computer work and a subsequent pause from computer work.  相似文献   
75.
Traditional hair-removal techniques have included shaving, waxing, chemical depilation, and electrolysis. All of these methods result in temporary hair removal. The theory of selective photo thermolysis led to the development of a variety of different laser systems. These lasers range from the short end of spectrum, with the 694-nm ruby laser, to the middle, with the 755-nm alexandrite and 810-nm diode lasers, and to the long end with the 1,064-nm Nd:YAG laser. We made a systematic review on the clinical trials with use of various laser sources for hair removal, so all clinical trials related to hair removal lasers in 1998–2003 were considered after elimination of heterogenite sources in data store. Trial results were synthetized on the basis of kind of laser. Our study clarified that hair reduction at least 6 months after the last treatment and hair reductions were 57.5, 42.3, 54.7, and 52.8% after three sessions for diode, Nd:YAG, alexandrite and ruby, respectively. We compared the result with use of analysis of variance method (Scheffes) and double comparison with use of Student’s t test. Our results clarified that diode laser is the most effective, and Nd:YAG has the least effect of hair removal.It seems that diode and alexandrite lasers are proper for hair removal, but as we need high fluence in the darker skin types and this is accompanied with higher complications, diode is advised for lighter skin, and we advised alexandrite laser for darker skin types.  相似文献   
76.
OBJECTIVES: To describe trends in perimortal conditions (pathological conditions causing death or present at death but not necessarily the reported cause of death) during three periods related to the availability of HAART, pre-HAART (1992-1995), early HAART (1996-1999), and contemporary HAART (2000-2003); annual mortality rates; and antiretroviral therapy (ART) prevalence during 1992-2003. DESIGN: Multicenter observational clinical cohort in the United States (Adult/Adolescent Spectrum of HIV Disease [ASD] project). METHODS: Proportionate mortality for selected perimortal conditions, annual mortality rates, and ART prevalence were standardized by sex, race/ethnicity, age at death, HIV transmission category, and lowest CD4 cell count of ASD decedents. Multivariable generalized linear regression was used to estimate trends in proportionate mortality, as linear trends through all three HAART periods, mortality rates, and ART prevalence. RESULTS: Of 9225 deaths, 58.6% occurred during 1992-1995, 29.5% during 1996-1999, and 11.9% during 2000-2003. Linear trends in proportionate mortality for noninfectious diseases (e.g., liver disease, hypertension, and alcohol abuse) increased significantly; proportionate mortality for AIDS-defining infectious diseases (e.g., pneumocystosis, nontuberculous mycobacterial disease, and cytomegalovirus disease) decreased significantly. Mortality rates decreased from 487.5/1000 person-years in 1995 to 100.6 in 2002. Of 36 256 patients from ASD, 75.7% (standardized average) were prescribed ART annually. CONCLUSIONS: Among HIV-infected patients, the majority of whom were prescribed ART, the increasing trend in common noninfectious perimortal conditions support screening and treatment for these conditions in order to sustain the trend in declining mortality rates.  相似文献   
77.
Gandomi H  Misaghi A  Basti AA  Hamedi H  Shirvani ZR 《Mycoses》2011,54(5):e429-e437
The mode of inhibitory action of Zataria multiflora Boiss. essential oil (EO) on the fungus, Aspergillus flavus, was studied by colony morphology examination, light microscopy, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The EO at concentrations used in this study suppressed the size of the colony as well as sporulation. SEM of mycelia treated with given concentrations of EO showed morphological alterations ranging from loss of turgidity and uniformity of mycelia at low concentrations of EO to evident destruction of the hyphae at higher concentration of EO. Semi-thin sections of mycelia exposed to different concentrations of EO were analysed by light microscopy and revealed that the major change at level as low as 50 ppm of EO was limited to vacuolisation of cytoplasm resulting in cell swelling, while at higher concentrations, detachment of the cell membrane from the cell wall, deformation of mycelia and shedding the cytoplasm from the cell were the main alterations. These damages were well documented by TEM, which showed that the main sites of action of EO were the plasma membrane and cell wall. In conclusion, morphological and structural changes observed in this study may be one of the mechanisms involved in growth inhibition of the fungi and reducing aflatoxin production.  相似文献   
78.
79.
The aim of this study was to determine platelet activity and reactivity and the effects of unfractionated heparin (UFH) and enoxaparin on platelet function during carotid eversion endarterectomy under local anesthesia. Twenty symptomatic patients undergoing carotid endarterectomy were randomly assigned to either 5,000 units of UFH or body weight-adjusted enoxaparin (0.5 mg/kg body weight) as an intraoperative intravenous bolus. The activity of platelets was assessed by measuring the expression of CD62p and CD41 with flow cytometry. Additionally, platelet-leukocyte aggregates (PLAs) were enumerated. The reactivity of platelets was evaluated by measuring the expression of the same antigens after stimulation. In addition, platelet reactivity was also analyzed using a PFA-100 analyzer. A significant increase in platelet activity was observed during surgery for CD41 and CD62p (p = .002 and < .001, respectively). The number of PLAs showed no significant changes during surgery. Yet there was a significant difference between patients treated with UFH and patients treated with enoxaparin. No difference for platelet activity or reactivity for patients receiving either UFH or enoxaparin prior to cross-clamping of the carotid arteries was seen. The formation of PLAs after endarterectomy was significantly higher in the UFH group; thus, PLAs are probably a useful surrogate parameter for measuring platelet activity.  相似文献   
80.
OBJECTIVE: Mechanical signals are key determinants in tissue morphogenesis, maintenance, and restoration strategies in regenerative medicine, although molecular mechanisms of mechanotransduction remain to be elucidated. This study was undertaken to investigate the mechanotransduction process of expression of superficial zone protein (SZP), a critical joint lubricant. METHODS: Regional expression of SZP was first quantified in cartilage obtained from the femoral condyles of immature bovines, using immunoblotting, and visualized by immunohistochemistry. Contact pressure mapping in whole joints was accomplished using pressure-sensitive film and a load application system for joint testing. Friction measurements on cartilage plugs were acquired under boundary lubrication conditions using a pin-on-disk tribometer modified for reciprocating sliding. Direct mechanical stimulation by shear loading of articular cartilage explants was performed with and without inhibition of transforming growth factor beta (TGFbeta) signaling, and SZP content in media was quantified by enzyme-linked immunosorbent assay. RESULTS: An unexpected pattern of SZP localization in knee cartilage was initially identified, with anterior regions exhibiting high levels of SZP expression. Regional SZP patterns were regulated by mechanical signals and correlated with tribological behavior. Direct relationships were demonstrated between high levels of SZP expression, maximum contact pressures, and low friction coefficients. Levels of SZP expression and accumulation were increased by applying shear stress, depending on location within the knee, and were decreased to control levels with the use of a specific inhibitor of TGFbeta receptor type I kinase and subsequent phospho-Smad2/3 activity. CONCLUSION: These findings indicate a new role for TGFbeta signaling in the mechanism of cellular mechanotransduction that is especially significant for joint lubrication.  相似文献   
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