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101.
102.
Efficacy of Oral Zinc Sulfate Supplementation on Clearance of Cervical Human Papillomavirus (HPV); A Randomized Controlled Clinical Trial 下载免费PDF全文
Hale AyatollahiElham RajabiZahra YektaZahra Jalali 《Asian Pacific journal of cancer prevention》2022,23(4):1285-1290
Aim: Human Papillomavirus is one of the most crucial infectious disease in gynecology disease. To assess the efficacy of supplemental zinc treatment in clearance of HPV infection. Methods: Eighty zinc-sufficient women between 21-55 years, with positive HPV DNA testing, and abnormal cervical cytology in Pap test (ASCUS or LISL) were randomly divided to case (n=40) and control group (n=40). Case group received oral tablets of zinc sulfate twice a day for 3 months while control group received no placebo. During follow-up patients underwent repeat HPV DNA test and PAP test and were evaluated for clearance/persistence of HPV infection and regression/progression in the lesion grading. Results: As far as demographics, serum zinc levels and the relevant risk factors for persistence of HPV were concerned, there was no significant difference between two groups, except for the frequency distribution of HR-HPV which was significantly higher in case group. Zinc treatment for 3 months reduced the risk of persistence of HPV infection and progression from baseline cytology (OR = 0.130) (CI 95% 0.04-0.381; p <0.001) and 0.301 (95% CI 0.777-0.116; p = 0.012), respectively. Age, initial cytology, HPV type, and contraceptive method were not related to persistence of HPV. Serum zinc levels increased in the casr group as a result of oral zinc consumption for 3-month period, though without any statistical significance (p = 0.407). Conclusion: The results of the following study suggested that oral intake of zinc sulfate supplement for 3 months increases the rates of HPV clearance and resolution of pre-existing cervical lesion. 相似文献
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Fahrettin Yildiz Alpaslan Terzi Sacid Coban Hakim Celik Nurten Aksoy Muharrem Bitiren Hale Çakir Mustafa K Ozdogan 《Journal of gastroenterology and hepatology》2009,24(11):1781-1785
Background and Aim: The aim of this study was to determine whether resveratrol could prevent intestinal tissue injury induced by ischemia–reperfusion (I/R).
Methods: Intestinal I/R was induced in rats' intestines by 60-min occlusion of the superior mesenteric artery, followed by a 60-min reperfusion. Thirty rats were divided into three groups as follows: sham (group 1), control (group 2), and the treatment groups (group 3). The rats in the treatment group received resveratrol both before ischemia and before reperfusion. In all groups, serum aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase levels were determined. Total antioxidant capacity (TAC), catalase, total oxidative status (TOS), oxidative stress index (OSI), and myeloperoxidase (MPO) in the intestinal tissue were measured. Intestinal tissue histopathology was also evaluated by light microscopy.
Results: The levels of liver enzymes in group 3 were significantly lower than those in group 2 ( P < 0.05). TAC in the intestinal tissue was significantly higher in group 3 than in group 2 ( P < 0.05). TOS, OSI, and MPO in the intestinal tissue were significantly lower in group 3 than in group 2 ( P < 0.05 for all). Histological tissue damage was milder in the resveratrol treatment group than in the control group.
Conclusions: The results of this study indicated that resveratrol treatment limits the oxidative injury of the small intestine induced by I/R in rats. However, more precise investigations are required to evaluate the antioxidative effect of resveratrol on small intestine tissue damage in clinical and experimental models. 相似文献
Methods: Intestinal I/R was induced in rats' intestines by 60-min occlusion of the superior mesenteric artery, followed by a 60-min reperfusion. Thirty rats were divided into three groups as follows: sham (group 1), control (group 2), and the treatment groups (group 3). The rats in the treatment group received resveratrol both before ischemia and before reperfusion. In all groups, serum aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase levels were determined. Total antioxidant capacity (TAC), catalase, total oxidative status (TOS), oxidative stress index (OSI), and myeloperoxidase (MPO) in the intestinal tissue were measured. Intestinal tissue histopathology was also evaluated by light microscopy.
Results: The levels of liver enzymes in group 3 were significantly lower than those in group 2 ( P < 0.05). TAC in the intestinal tissue was significantly higher in group 3 than in group 2 ( P < 0.05). TOS, OSI, and MPO in the intestinal tissue were significantly lower in group 3 than in group 2 ( P < 0.05 for all). Histological tissue damage was milder in the resveratrol treatment group than in the control group.
Conclusions: The results of this study indicated that resveratrol treatment limits the oxidative injury of the small intestine induced by I/R in rats. However, more precise investigations are required to evaluate the antioxidative effect of resveratrol on small intestine tissue damage in clinical and experimental models. 相似文献
107.
Guido Germano Paul B Kavanagh Piotr J Slomka Serge D Van Kriekinge Geoff Pollard Daniel S Berman 《Journal of nuclear cardiology》2007,14(4):433-454
Cedars-Sinai's approach to the automation of gated perfusion single photon emission computed tomography (SPECT) imaging is based on the identification of key procedural steps (processing, quantitation, reporting), each of which is then implemented, in completely automated fashion, by use of mathematic algorithms and logical rules combined into expert systems. Our current suite of software applications has been designed to be platform- and operating system-independent, and every algorithm is based on the same 3-dimensional sampling scheme for the myocardium. The widespread acceptance of quantitative software by the nuclear cardiology community (QGS alone is used at over 20,000 locations) has provided the opportunity for extensive validation of quantitative measurements of myocardial perfusion and function, in our opinion, helping to make nuclear cardiology the most accurate and reproducible modality available for the assessment of the human heart. 相似文献
108.
Douglas KM Potter T Treharne GJ Obrenovic K Hale ED Pace A Mitton D Erb N Whallett A Delamere JP Kitas GD 《Rheumatology (Oxford, England)》2005,44(1):80-82
OBJECTIVES: To determine the preferences of rheumatology patients for the time and location of their out-patient appointments. METHODS: All patients attending the rheumatology out-patient services at Dudley Group of Hospitals NHS Trust over a 2-week period were asked to complete a purpose-designed, scannable, previously piloted, self-administered questionnaire. RESULTS: Four hundred and nineteen patients completed questionnaires (response rate 87%). Age ranged from 16 to 92 yr; 38% of responders were over 65 yr, 72% were female, 57% had an inflammatory arthritis, 20% had a connective tissue disease, 8% had degenerative joint disease and 15% had another diagnosis; 29% were employed, 51% retired and 20% unemployed. Fewer than 1% of patients would like to be seen at community general practice centres (99.3% would prefer a hospital site). Proximity to their home was the main determinant of hospital choice. Monday was the most popular day for appointments, and days from Tuesday to Friday received equal rankings. Only 0.5% of patients would choose a weekend clinic. Fifty-eight per cent of patients would prefer morning appointments, 24% afternoon appointments and 2% evening appointments; 16% did not mind. Only being employed predicted out-of-hours preference. CONCLUSIONS: In this predominantly suburban, industrialized area, rheumatology out-patients prefer to be seen in the hospital rather than primary care environment, ideally close to their home, with appointments in the morning and on a weekday. These results may be generalizable to other districts and other chronic disease states, but we suggest that similar surveys become part of routine service provision and inform current and future planning. 相似文献
109.
Marc M. Hirschmann Edwin A. Bergin Geoff A. Blake Fred J. Ciesla Jie Li 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(13)
During the formation of terrestrial planets, volatile loss may occur through nebular processing, planetesimal differentiation, and planetary accretion. We investigate iron meteorites as an archive of volatile loss during planetesimal processing. The carbon contents of the parent bodies of magmatic iron meteorites are reconstructed by thermodynamic modeling. Calculated solid/molten alloy partitioning of C increases greatly with liquid S concentration, and inferred parent body C concentrations range from 0.0004 to 0.11 wt%. Parent bodies fall into two compositional clusters characterized by cores with medium and low C/S. Both of these require significant planetesimal degassing, as metamorphic devolatilization on chondrite-like precursors is insufficient to account for their C depletions. Planetesimal core formation models, ranging from closed-system extraction to degassing of a wholly molten body, show that significant open-system silicate melting and volatile loss are required to match medium and low C/S parent body core compositions. Greater depletion in C relative to S is the hallmark of silicate degassing, indicating that parent body core compositions record processes that affect composite silicate/iron planetesimals. Degassing of bare cores stripped of their silicate mantles would deplete S with negligible C loss and could not account for inferred parent body core compositions. Devolatilization during small-body differentiation is thus a key process in shaping the volatile inventory of terrestrial planets derived from planetesimals and planetary embryos.Major volatiles (H, C, N, and S) are inherently plentiful in the interstellar medium and abundant in primitive carbonaceous chondrites (CCs) (1, 2), but are scarce in terrestrial planets, which gained most of their mass from the inner parts of the solar nebula (3, 4). Formation of volatile-poor planets from a volatile-rich protoplanetary disk is a result of processes in the solar nebula, in accretion of precursor solids, and in interior differentiation. Addition of volatiles to nascent planets varies during accretion as protoplanetary systems become dynamically excited, contributing material originating from different heliocentric distances (3) and with different thermal histories. Much of this mass arrives in larger bodies (planetesimals or planetary embryos) that differentiated soon after formation (5). Key uncertainties include the nebular history of bulk materials that contributed volatiles to the rocky planets and how that affected their volatile cargos (6), and how planetesimal and planet formation influenced volatile distributions in accreted parent bodies.Processes responsible for volatile deficits in terrestrial planets (7, 8) can occur either in the nebular, planetesimal, or planetary environment. Nebular volatile depletion could result from chemical interactions between nebular gas and dust, chondrule formation, or the accretion of thermally processed solids (9–11), perhaps owing to the hotter conditions prevailing closer to the protosun (4). Li et al. (6) argue that the comparatively small C inventory of the bulk Earth requires that nebular materials experienced significant early (<1 Ma) heating, before the “soot line” moved inward of 1 AU. Planetesimal processes involve loss to space during differentiation or processing of intermediate-sized bodies of tens to hundreds of kilometers in diameter (e.g., refs. 12 and 13). Planetary loss processes occur on large (thousands of kilometers in diameter) bodies (14, 15) in which gravity plays an appreciable role—including loss from impacts (16). The sum of these is an important determinant for whether terrestrial planets form with volatiles sufficient for habitability but not so great as to become ocean worlds (17) or greenhouse hothouses (18).A key goal in the study of exoplanets and of young stellar systems is predicting environments and processes that could lead to habitable planets, including development of models that account for the distribution, acquisition, and loss of key volatile elements. Astronomical studies can reveal the architecture of other solar systems (19), the compositions of observable exoplanet atmospheres (ref. 20 and references therein), and the dust and volatile gas structure and composition of protoplanetary disks (ref. 21 and references therein), including interactions of the disk with gas- or ice-giant protoplanets. However, only limited astronomical observations can be made about conversion of disk materials (gas, dust, and pebbles) to planets in other solar systems. To understand this conversion, we must necessarily rely on planetesimals and their remnants (meteorites) as records of the processes that occurred. In this paper, we focus on volatile loss during planetesimal differentiation by examining evidence chiefly from iron meteorites. We note that ephemeral metal enrichments in white dwarf atmospheres confirm that differentiated planetesimals are common around other stars (22), and that our findings apply to how materials would have been processed during the assembly of other planetary systems.In classic oligarchic growth models of planetary origin, planets and embryos grow from accretion of planetesimals with characteristic radii of tens to a few hundreds of kilometers (3). In pebble accretion models of terrestrial planet formation, the fraction of planetesimals in accreting material varies with time and protoplanetary mass (23), but still remains significant. Thus, for understanding volatile delivery to growing planets, an important question is whether the volatile inventory of accreting planetesimals (or larger objects) remained similar to that of primitive materials, typically taken to be comparable to chondritic meteorites, or had diminished significantly from prior differentiation.*Achondritic meteorites are fragments of differentiated planetesimals and provide direct evidence of processes on small bodies.† Evidence for volatile loss on silicate achondritic parent bodies comes from elemental concentrations and from isotopes (24–27). However, the best-studied silicate achondritic suites, such as the eucrites and angrites, are igneous crustal rocks (28), and their compositions may not reflect average major volatile contents of their parent bodies. Volatile loss could have been locally enhanced by the igneous activity that produced the planetesimal crusts (29).Iron meteorites offer an additional record of volatile processing in planetesimals. Many, known as “magmatic” irons, originated as metallic cores of planetesimals (30) and potentially record volatile depletions in their parent planetesimals at the time of alloy–silicate separation. Iron meteorites contain measurable amounts both major (S, C, N) and moderately volatile (Ge, Ga) elements and represent the cores of at least 50 parent bodies (31). Thus, known parent body cores are likely survivors from a population of planetesimals that were mostly incorporated into larger bodies and planets. Additionally, isotopic evidence links iron meteorites with both carbonaceous (CC) and noncarbonaceous (NC) chondrites (32), thereby correlating the differentiated planetesimals to their primitive chondritic heritage.Here, we address the problem of planetesimal volatile loss by focusing on carbon and sulfur, two siderophile volatile elements that give important clues to the degassing history of metallic cores recorded iron meteorites and thereby their parent planetesimals.‡ We begin by examination of C–S systematics in different classes of chondrites. Although chondritic parent bodies formed later than most parent bodies of iron meteorites (33), they provide the best available guide to undifferentiated materials in the early solar system. Their isotopic kinships to iron meteorites (32) suggest that they derive from similar, although not necessarily identical, reservoirs, and so they provide a basis for comparison to those estimated for parent body cores. They also reveal devolatilization processes associated with planetesimal metamorphism. We then examine iron meteorite groups and reconstruct the compositions of their respective parent cores. Finally, we consider a spectrum of simple planetesimal core-formation scenarios and model the resulting C and S distributions. Comparison of these to reconstructed parent core C and S places new constraints on the magnitude of degassing occurring from planetesimal interiors. 相似文献
110.
Decreased treatment failure in recipients of HLA-identical bone marrow or peripheral blood stem cell transplants with high CD34 cell doses 总被引:3,自引:0,他引:3
Ringdén O Barrett AJ Zhang MJ Loberiza FR Bolwell BJ Cairo MS Gale RP Hale GA Litzow MR Martino R Russell JA Tiberghien P Urbano-Ispizua A Horowitz MM 《British journal of haematology》2003,121(6):874-885
We studied the association between CD34 cell dose and transplant outcomes in 359 bone marrow (BM) and 511 peripheral blood stem cell (PBSC) transplant recipients from human leucocyte antigen (HLA)-identical siblings, reported to the International Bone Marrow Transplant Registry (IBMTR). Transplants for leukaemia were performed between 1995 and 1998. Patients were divided into those receiving below or above the median CD34+ dose, for BM (3 x 106/kg) and PBSC (6 x 106/kg) grafts respectively. Cox proportional hazards regression was used to adjust for baseline patient-, disease- and transplant-related characteristics. Analysis of the BM recipients showed that high CD34 cell dose was associated with lower transplant-related mortality [relative risk (RR) = 0.60, P = 0.033] and treatment failure (inverse of leukaemia-free survival, RR = 0.69, P = 0.032). Among PBSC recipients, high CD34 dose was associated with faster recovery of neutrophils to > 0.5 x 109/l (RR = 1.38, P < 0.001) and platelets to > 20 x 109/l (RR = 1.34, P = 0.003), lower risk of relapse (RR = 0.62, P = 0.029) and treatment failure (RR = 0.74, P = 0.03). We conclude that higher CD34 cell doses decrease treatment failure in recipients of HLA-identical sibling BM and PBSC transplants. 相似文献