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排序方式: 共有311条查询结果,搜索用时 296 毫秒
1.
Blood lactate assays are now widely used as measures of oxygen debt, especially in the areas of assessment of anaerobic power; assessment of fatigue; VO2(max) end-point determination, and rationalisation of work-rest cycles. A need exists for a method which will meet the following criteria: simplicity--single, small samples; rapidity, and feasibility with easily available instrument and chemicals. In order to develop such a method, the standard Barker and Summerson method was modified so as to use 0.02 ml of blood sample, and the following tests were carried out on 25 subjects at rest, and various levels of work: paired comparisons on analysis by macro and micro methods on the same sample of blood; paired comparisons on venous and capillary (fingertip) samples. In both cases, the paired values showed high correlation (0.99) and highly significant differences of means (P = 0.01 and 0.001, respectively). The regression equations obtained were also highly significant (P = 0.001). The combined equation was Y = 0.9655 X -0.4366; samples taken 2,4,5,6 and 10 mins after work showed that peak occurred in the 4th min sampling (2 vs 4 and 4 vs 6 min means significantly different at P = 0.05, and analysis of variance significant at (P = 0.001). It may be concluded that drawing, fingertip sample 4 mins after the end of work, analysing by the micro method, and using the regression equation will give the true peak blood lactate level, and satisfy the systems criteria defined.  相似文献   
2.
Summary. Cotton leaf curl disease (CLCuD) causing viruses belong to the Begomovirus genus of the family Geminiviridae. Most begomoviruses are bipartite with two molecules of circular single stranded DNA (A and B) encapsidated in icosahedral geminate particles. However, the begomoviruses associated with CLCuD have DNA- instead of DNA-B. In this communication we report the complete genomic sequence of DNA-A component of two CLCuD-causing begomoviruses, cotton leaf curl Kokhran virus-Dabawali (CLCuKV-Dab), tomato leaf curl Bangalore virus-Cotton [Fatehabad] (ToLCBV-Cotton [Fat]) and partial sequences of two other isolates cotton leaf curl Rajasthan virus-Bangalore (CLCuRV-Ban) and cotton leaf curl Kokhran virus-Ganganagar (CLCuKV-Gang). A phylogenetic analysis of these isolates along with other related begomoviruses showed that ToLCBV-Cotton [Fat] isolate was closest to the tomato leaf curl Bangalore virus-5 (ToLCBV-Ban5) where as CLCuKV-Dab isolate was close to the cotton leaf curl Kokhran virus-Faisalabad1 (CLCuKV-Fai1), cotton leaf curl Kokhran virus-72b (CLCuKV-72b) and cotton leaf curl Kokhran virus-806b (CLCuKV-806b) isolates from Pakistan. The phylogenetic analysis further showed that the ToLCBV-Cotton [Fat] and CLCuKV-Dab isolates along with CLCuKV-Fai1, CLCuKV-72b and CLCuKV-806b are closer to the ToLCBV, tomato leaf curl Gujarat virus (ToLCGV), tomato leaf curl Gujarat virus-Varanasi (ToLCGV-Var) and tomato leaf curl Sri Lanka virus (ToLCSLV) isolates, where as cotton leaf curl Alabad virus-804a (CLCuAV-804a), cotton leaf curl Multhan virus (CLCuMV) cluster with the isolates from cotton leaf curl Rajasthan virus (CLCuRV) and okra yellow vein mosaic virus (OYVMV). These results demonstrate the extensive variability observed in this group of viruses. The AC4 ORF is the least conserved among these viruses. In order to further asses the variability in the CLCuD-causing begomoviruses, the region showing minimum similarity in the DNA-A sequence was first determined by a comparison of segments of different lengths of the aligned sequences. The results indicated that region 2411–424 (771nt) was the least conserved. A phylogenetic tree constructed using the sequences of all the CLCuD causing begomoviruses, corresponding to the least conserved region showed that they form two distinct clusters.  相似文献   
3.
Since the outbreak of COVID‐19 pandemic, clinicians have had to use personal protective equipment (PPE) for prolonged periods. This has been associated with detrimental effects, especially in relation to the skin health. The present study describes a comprehensive survey of healthcare workers (HCWs) to describe their experiences using PPE in managing COVID‐19 patients, with a particular focus on adverse skin reactions. A 24‐hour prevalence study and multi‐centre prospective survey were designed to capture the impact of PPE on skin health of hospital staff. Questionnaires incorporated demographics of participants, PPE type, usage time, and removal frequency. Participants reported the nature and location of any corresponding adverse skin reactions. The prevalence study included all staff in intensive care from a single centre, while the prospective study used a convenience sample of staff from three acute care providers in the United Kingdom. A total of 108 staff were recruited into the prevalence study, while 307 HCWs from a variety of professional backgrounds and demographics participated in the prospective study. Various skin adverse reactions were reported for the prevalence study, with the bridge of the nose (69%) and ears (30%) being the most affected. Of the six adverse skin reactions recorded for the prospective study, the most common were redness blanching (33%), itchiness (22%), and pressure damage (12%). These occurred predominantly at the bridge of the nose and the ears. There were significant associations (P < .05) between the adverse skin reactions with both the average daily time of PPE usage and the frequency of PPE relief. The comprehensive study revealed that the use of PPE leads to an array of skin reactions at various facial locations of HCWs. Improvements in guidelines are required for PPE usage to protect skin health. In addition, modifications to PPE designs are required to accommodate a range of face shapes and appropriate materials to improve device safety.  相似文献   
4.
Alpha‐cypermethrin is an isoform of cypermethrin; it is an active pyrethroid used extensively to control a wide range of pests in agriculture and animal breeding. In this study four groups of six fish were examined. The first group served as a control in fresh water alone, with no pyrethroid. The second, third and fourth groups were exposed to alpha‐cypermethrin for 4, 8 and 96 h respectively. At the end of the each exposure period, the fish were sacrificed, and the required muscle tissues were collected for histological examination. The blood was drawn with heparinized needles and processed for serum enzymatic studies. Serum enzymes such as aspartate transaminase (AST), alanine transaminase (ALT), amylase, acid phosphatase (ACP) and gamma‐glutamyl transpeptidase (GGT) were measured at 4, 8 and 96 h. AST enzyme activity was significantly increased at 4 h, whereas ALT and amylase enzyme activities were significantly reduced at all the time points. ACP enzyme activity was significantly reduced at 4 and 8 h, whereas GGT enzyme activity was significantly increased at all the time points. Hepatocyte cytoplasmic vacuolisation and degeneration, rupture of blood vessels, and necrosis was found at all time points. Congestion of blood vessels, bulging, distortion of filaments, erosion and disintegration of blood corpuscles and hyperplasia of epithelium were found in treated gills at 4, 8 and 96 h. Breakdown of muscle fibres, vacuolation and accumulation of lipids and melanin in white muscle were observed in treated fish muscle at 4, 8 and 96 h.  相似文献   
5.
6.
AIMS: The biological effects of oestrogens are mediated by two different oestrogen receptor (ER) subtypes, ERalpha and ERbeta, which might play different, redundant, or opposing roles in cardiovascular disease. Previously, we have shown that the selective ERalpha agonist 16alpha-LE2 improves vascular relaxation, attenuates cardiac hypertrophy, and increases cardiac output without lowering elevated blood pressure in spontaneously hypertensive rats (SHR). Because ERbeta-deficient mice exhibit elevated blood pressure and since the ERbeta agonist 8beta-VE2 attenuated hypertension in aldosterone-salt-treated rats, we have now tested the hypothesis that the isotype-selective ERbeta agonist 8beta-VE2 might be capable of lowering elevated blood pressure in ovariectomized SHR. METHODS AND RESULTS: Treatment of ovariectomized SHR with 8beta-VE2 for 12 weeks conferred no uterotrophic effects but lowered elevated systolic blood pressure (-38 +/- 5 mmHg, n = 31, P < 0.001 vs. placebo) as well as peripheral vascular resistance (-31.3 +/- 4.6%, P < 0.001 vs. placebo). 8beta-VE2 enhanced aortic ERbeta expression (+75.7 +/- 7.1%, P < 0.01 vs. placebo), improved NO-dependent vasorelaxation, augmented phosphorylation of the vasodilator-stimulated phosphoprotein in isolated aortic rings (P < 0.05 vs. placebo), increased cardiac output (+20.4 +/- 2.5%, P < 0.01 vs. placebo), and attenuated cardiac hypertrophy (-22.2 +/- 3.2%, p < 0.01 vs. placebo). 8beta-VE2, in contrast to oestradiol, did not enhance cardiac alpha-myosin heavy chain expression. CONCLUSION: Ligand-dependent activation of ERbeta confers blood pressure lowering effects in SHR that are superior to those of 17beta-estradiol or the ERalpha agonist 16alpha-LE2 and attenuates cardiac hypertrophy primarily by a reduction of cardiac afterload without promoting uterine growth.  相似文献   
7.
Polyaniline (PANI)/Cu–ZnS composites with porous microspheres are prepared by a hydrothermal and in situ polymerization method. The structural, optical, and morphological properties are characterized by X-ray powder diffraction, FTIR, UV-vis, scanning electron microscope, transmission electron microscope. The XRD results confirmed that the PANI/Cu–ZnS composite is formed. The morphological analyses exhibited that the PANI/Cu–ZnS composite comprises the porous microspherical structures. The emission peaks obtained in photoluminescence spectra confirm the presence of surface defects in the prepared composite. The UV-DRS study shows that the bandgap of the samples is found to decrease for the PANI/Cu–ZnS composite compared to the pure Cu–ZnS sample. The calculated band gap (Eg) value of PANI/Cu–ZnS composite is 2.47 eV. Furthermore, the fabricated gas sensor based on PANI/Cu–ZnS can perform at room temperature and exhibits good gas sensing performance toward CO2 gas. In particular, PANI/Cu–ZnS sensor shows good response (31 s) and recovery time (23 s) upon exposure to CO2 gas. The p/n heterojunction, surface defects, and porous nature of the PANI/Cu–ZnS composite microsphere enhanced sensor performance.

Polyaniline (PANI)/Cu–ZnS composites with porous microspheres are prepared by a hydrothermal and in situ polymerization method.  相似文献   
8.
The internal iliac artery (IIA) arises from the common iliac artery at the level of the sacroiliac joint. It descends as trunk, divides into anterior and posterior divisions. From the anterior division it gives superior vesical, obturator, middle rectal, inferior vesical, inferior gluteal, and internal pudendal arteries. In females, inferior vesical artery is replaced by vaginal artery and gives an additional branch, uterine artery. The branches from the posterior division are ilio lumbar, lateral sacral, and superior gluteal arteries. An accidental hemorrhage and neurovascular injuries are common due to erroneous interpretation of variant arteries during surgical procedures. Hence the present study has been undertaken with reference to highlight its clinical and surgical significances. The study included 50 human bisected pelvises irrespective of their side and sex. Formalin-fixed specimens were selected and the branching patterns of IIA were studied. The level of origin, length, and the branching pattern of the IIA were examined and tabulated. The present study highlighted the variation seen in the origin, division branches of the IIA. The detailed knowledge of morphology is essential for successful ligation of the IIA during acute hemorrhage. This will guide the interventional radiologist in intra-arterial procedures during arterial embolization for hemorrhage, control of pelvic fractures, during selective catheterization of the intra-arterial chemotherapy, and embolization of the pelvic tumors.  相似文献   
9.
The long-term effects of prenatal ethanol exposure on the properties of brain polysomes and the proliferative responses of lymphocytes to mitogenic stimulation in adult offspring were assessed. Female Sprague-Dawley rats either ingested the control or 6.6% ethanol-containing Lieber-DeCarli liquid diet during the 3rd trimester of pregnancy. Controls were age-matched and pair-fed. At 42 to 72 days of age, ethanol effects were evaluated on the (1) polysomal properties in the cerebral hemispheres, cerebellum, and hippocampal regions of the brain after translation in a messenger RNA (mRNA)-dependent rabbit reticulocyte lysate system and (2) immunologic functions of lymphocytes cultured from spleen cells by measuring their responses to mitogenic stimulation. Results showed long-term adverse effects of in utero ethanol exposure on the polysomal RNA translation in each of the three brain regions tested with free polysomal mRNAs affected more than the bound polysomal mRNAs. Of these, the hippocampal region appeared to sustain the most injurious effects. In addition, a suppression of the mitogen-induced lymphocyte proliferative responses were present under these conditions. The degree of suppression varied with the specific mitogen used. Data suggest that the ethanol effects on the CNS and lymphocyte proliferation are most possibly irreversible, and in the case of the CNS, a post-translational modification by ethanol is indicated. The reduced lymphocyte responses are suggestive of a possible interference by ethanol of the synthesis of interleukin-2 (IL-2) and/or a reduced binding of IL-2 with its receptor (IL-2 receptors).  相似文献   
10.
Liposarcoma of the paratesticular region is a rare malignant soft tissue neoplasm. Out of all the possible sites of liposarcoma, the incidence in spermatic cord is rare, accounting for only 5% of these neoplasms. Among the various subtypes of liposarcoma described in the paratesticular region, myxoid variant of liposarcoma is seen very rarely. One such case is we ported here for its rarity and also to draw attention to the fact that, early diagnosis and complete excision carry better prognostic value.  相似文献   
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