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991.
Ljungberg K Hassan MS Islam MN Siddiqui MA Aziz MM Wahren B Islam KB Leitner T 《AIDS research and human retroviruses》2002,18(9):667-670
We analyzed the genetic diversity of HIV-1 circulating in Bangladesh by direct sequencing and subsequent phylogenetic analysis of the V3 region of the env gene and p17 fragment of the gag gene from nine unrelated patients. The sequences from one sample grouped into subtype A, five samples grouped into subtype C, and one grouped into subtype G. In addition, two patients appeared to be infected with different recombinant viruses consisting of subtype A and unclassifiable viral sequences. Epidemiological analysis revealed heterosexual transmission in the majority of cases. Furthermore, most subjects had a history of traveling, either to India or to the Arabian Peninsula. This study shows that several HIV-1 subtypes are circulating in Bangladesh, and we conclude that there must have been several introductions of HIV-1 into the Bangladeshi population. 相似文献
992.
El-Zayadi AR Selim O Hamdy H El-Tawil A Moustafa H 《The American journal of gastroenterology》2002,97(5):1264-1265
993.
K.D John I. Segal H. Hassan R. D. Levy M. Amin 《Journal of gastrointestinal cancer》1997,21(2):149-155
Summary
Conclusion In African blacks, acute pancreatitis requiring hospital adminission is a severe disease associated with a high mortality
and significant long-term morbidity in surviving patients.
Background It has been suggested that acute pancreatitis has a benign course in Africans in contrast to Western populations. The aim
of the present study was to ascertain the incidence of acute pancreatitis at Baragwanath Hospital for a 1-yr period and to
test the validity of the above hypothesis.
Methods One hundred thirty-six patients with acute pancreatitis were retrospectively assessed. Fifty patients were available for a
prospective follow-up examination and underwent sonographic and biochemical investigations. Acute pancreatitis was diagnosed
if the patient presented with the typical clinical picture and a raised serum amylase level >800 U/L.
Results The study consisted of 108 male and 28 female patients. Alcohol was identified as the predominant etiologic factor in 83.1%,
biliary disease in 7.4%, and idiopathic causes in 6.6%. Substantial morbidity was encountered in 32.3% and was caused mainly
by pancreatic complications, metabolic derangements, alcohol-related symptoms, and respiratory impairment. A portion (10.3%)
of the patients developed further pancreatic pathology, such as pseudocysts, necroses, or an abscess. The overall mortality
rate was 8.1%. Patients who died had a higher mean serum amylase, and most deaths occurred within 2 d of admission. Prospective
follow-up after an average of 9.3 mo revealed serious morbidity in two-thirds of patients. Fifty-two percent suffered from
severe abdominal pain, 36% complained of weight loss, and 18% were shown to have a sonographically abnormal pancreas. Fecal
chymotrypsin levels indicated exocrine pancreatic impairment in 30.6%
This work was presented at the South African Gastroenterology Society on September 12, 1995, in Sun City, South Africa. 相似文献
994.
Shereen Mohamed Elhoseiny Dalia Saber Morgan Asmaa Mohamed Rabie Samer Tharwat Bishay 《Indian journal of hematology & blood transfusion》2016,32(2):228-238
Vitamin D is critical for calcium, phosphate homeostasis and for mineralization of the skeleton, especially during periods of rapid growth. Vitamin D Deficiency leads to rickets (in children) and osteomalacia (in adults). Expression and activation of the vitamin D receptor (VDR) are necessary for the effects of vitamin D, in which several single nucleotide polymorphisms have been identified especially (FokI, BsmI). In this study serum 25 (OH) vitamin D3 levels were estimated by Enzyme Linked Immunosorbent Assay [ELISA], VDR (FokI, BsmI) gene polymorphisms were analyzed by polymerase chain reaction-restriction fragment length polymorphism assay [PCR–RFLP].Serum levels of calcium, phosphorus, alkaline phosphatase and ferritin were determined in 50 Pediatrics beta thalassemia major patients and 60 controls. Patients had significantly lower serum calcium (p < 0.001) lower serum vitamin D3 (p < 0.001) with elevated levels of phosphorus (p < 0.001) and alkaline phosphatase than controls (p = 0.04). Of the patients studied, 60 % had vitamin D deficiency (<20 ng/ml), 20 % had vitamin D insufficiency (21–30 ng/ml) and 20 % had sufficient vitamin D status (>30 ng/ml). Patients harboring mutant (Ff,ff) and wild (BB) genotypes were associated with lower serum calcium (p = 0.08, 0.02) respectively, lower vitamin D3 levels (p < 0.001, 0.01) respectively. They were also suffering from more bony complications although the difference was not statistically significant (p > 0.05). In conclusion, these results suggest that the VDR (FokI, BsmI) gene polymorphisms influence vitamin D status, (Ff,ff), BB genotypes had lower vitamin D levels, so they might influence risk of development of bone diseases in beta thalassemia major. 相似文献
995.
Bashir A Hassan AA Salmah MR Rahman WA 《The Southeast Asian journal of tropical medicine and public health》2008,39(2):222-228
The efficacy of the larvicidal and pupicidal agent (Agnique) MMF was evaluated against larvae of An. arabiensis and Culex (Diptera: Culicidae) under field conditions in Bahary Locality, Khartoum, Sudan. At an applied dosage of 0.25 ml/m2, MMF resulted in 89.4, 79.8 and 88.2% reductions in L3-L4 instars An. arabiensis and 63.5% in Culex larvae (all stages) 24 to 72 hours post-treatment. Pupae were completely eliminated (100%) within 24 hours posttreatment. The earlier instars (L1-L2) of An. arabiensis were more tolerant with a 62.5% reduction at 72 hours post-treatment compared to (L3-L4) instars and pupae. At 7-days post-treatment Agnique gave a 57.5% reduction in L1-L2 and 92.6% in L3-L4 instar larvae of An. arabiensis and 57.3% and 86.4% in Culex larvae and pupae, respectively. We conclude that Agnique can perform effectively against L3-L4 instars and pupae of An. arabiensis for only 1 week, and 3 to 4 days against L1-L2 instars of Culex spp. 相似文献
996.
Jaya Chandrasekhar Usman Baber Samantha Sartori Melissa Aquino Annapoorna S. Kini Sunil Rao William Weintraub Timothy D. Henry Serdar Farhan Birgit Vogel Sabato Sorrentino Zhen Ge Samir Kapadia Joseph B. Muhlestein Sandra Weiss Craig Strauss Catalin Toma Anthony DeFranco Roxana Mehran 《The Canadian journal of cardiology》2018,34(3):319-329
Background
Potent P2Y12 inhibitors might offer enhanced benefit against thrombotic events in complex percutaneous coronary intervention (PCI). We examined prasugrel use and outcomes according to PCI complexity, as well as analyzing treatment effects according to thienopyridine type.Methods
PROMETHEUS was a multicentre observational study that compared clopidogrel vs prasugrel in acute coronary syndrome patients who underwent PCI (n = 19,914). Complex PCI was defined as PCI of the left main, bifurcation lesion, moderate-severely calcified lesion, or total stent length ≥ 30 mm. Major adverse cardiac events (MACE) were a composite of death, myocardial infarction, stroke, or unplanned revascularization. Outcomes were adjusted using multivariable Cox regression for effect of PCI complexity and propensity-stratified analysis for effect of thienopyridine type.Results
The study cohort included 48.9% (n = 9735) complex and 51.1% (n = 10,179) noncomplex patients. Second generation drug-eluting stents were used in 70.1% complex and 66.2% noncomplex PCI patients (P < 0.0001). Complex PCI was associated with greater adjusted risk of 1-year MACE (hazard ratio [HR], 1.29; 95% confidence interval [CI], 1.20-1.39; P < 0.001). Prasugrel was prescribed in 20.7% of complex and 20.1% of noncomplex PCI patients (P = 0.30). Compared with clopidogrel, prasugrel significantly decreased adjusted risk for 1-year MACE in complex PCI (HR, 0.79; 95% CI, 0.68-0.92) but not noncomplex PCI (HR, 0.91; 95% CI, 0.77-1.08), albeit there was no evidence of interaction (P interaction = 0.281).Conclusions
Despite the use of contemporary techniques, acute coronary syndrome patients who undergo complex PCI had significantly higher rates of 1-year MACE. Adjusted magnitude of treatment effects with prasugrel vs clopidogrel were consistent in complex and noncomplex PCI without evidence of interaction. 相似文献997.
Loren Koillari Mark E. Olson Samir Suweis Rodrigo P. Rocha Alberto Lovison Franco Cardin Todd E. Dawson Alberto Echeverría Alex Fajardo Silvia Lechthaler Cecilia Martínez-Prez Carmen Regina Marcati Kuo-Fang Chung Julieta A. Rosell Alí Segovia-Rivas Cameron B. Williams Emilio Petrone-Mendoza Andrea Rinaldo Tommaso Anfodillo Jayanth R. Banavar Amos Maritan 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(22)
Shaping global water and carbon cycles, plants lift water from roots to leaves through xylem conduits. The importance of xylem water conduction makes it crucial to understand how natural selection deploys conduit diameters within and across plants. Wider conduits transport more water but are likely more vulnerable to conduction-blocking gas embolisms and cost more for a plant to build, a tension necessarily shaping xylem conduit diameters along plant stems. We build on this expectation to present the Widened Pipe Model (WPM) of plant hydraulic evolution, testing it against a global dataset. The WPM predicts that xylem conduits should be narrowest at the stem tips, widening quickly before plateauing toward the stem base. This universal profile emerges from Pareto modeling of a trade-off between just two competing vectors of natural selection: one favoring rapid widening of conduits tip to base, minimizing hydraulic resistance, and another favoring slow widening of conduits, minimizing carbon cost and embolism risk. Our data spanning terrestrial plant orders, life forms, habitats, and sizes conform closely to WPM predictions. The WPM highlights carbon economy as a powerful vector of natural selection shaping plant function. It further implies that factors that cause resistance in plant conductive systems, such as conduit pit membrane resistance, should scale in exact harmony with tip-to-base conduit widening. Furthermore, the WPM implies that alterations in the environments of individual plants should lead to changes in plant height, for example, shedding terminal branches and resprouting at lower height under drier climates, thus achieving narrower and potentially more embolism-resistant conduits.Water transport through plants is a key driver of the carbon and other biogeochemical cycles (1–3) and is a crucial link in plant adaptation to climate and vegetation response to climate change (4–9). The water conducting cells of plants, xylem conduits, widen with distance from the stem tip, and, therefore, taller plants have wider conduits (6, 10–12). Xylem conduits are of two main types: tracheids, found in most gymnosperms, and vessels, found in most flowering plants. Tracheids have intact cell membranes, so water must flow from cell to cell through these membranes. Vessels are made up of cells aligned vertically end to end, with the cell membranes dissolved between successive members, forming a tube. Whatever their differences in structure, wider conduits are beneficial because they conduct more water. Tip-to-base widening is expected to help maintain conductance per unit leaf area constant as an individual plant grows taller, counterbalancing the resistance that would otherwise accrue with increasing conductive path length the individual grows (2, 13). Wider conduits, however, are more vulnerable to embolisms caused by cold and likely drought (8, 14–18) and cost more in terms of carbon for a plant (ref. 1; cf. ref. 19). Embolisms in the xylem even affect transport of photosynthates in the phloem (8, 20). This means that as trees grow taller, conductance, embolism vulnerability, and carbon costs must interrelate in a delicate evolutionary balance.Because of the importance of this balance in plant hydraulic evolution and in forest reactions to climate change (3, 6, 21–23), an important goal of plant biology is to construct models that predict how and why plants deploy conduit diameters throughout their bodies (1, 2, 17, 24–26). Some models predict that conduits should be of uniform diameter (27, 28), while others predict that they should widen tip to base (1, 2, 13, 24, 29, 30). But even current models include untested assumptions and large numbers of parameters, making it difficult to identify the biological causes of the predictions they make. For example, some invoke Da Vinci’s rule, the largely untested assumption that the summed wood area of the twigs is the same as that at the base (24, 26). Other models depict plant conduits as branching as they do in mammalian circulatory systems, but whether this happens along the entire stem in plants is unclear (30–33). There is an expectation that conduit diameter D should widen with distance from the stem tip L following a power-law (D ∝ Lb), but there is no agreement on the value of b, the conduit widening exponent (1, 2). Furthermore, even though within-individual tip-to-base conduit widening has been confirmed in a handful of species (34–36), and the scaling of conduit diameter with plant size across species is consistent with it (6, 10–12, 34), the expectation that conduits should widen similarly within stems across terrestrial vascular plant lineages and habits has yet to be empirically confirmed. Here we present the Widened Pipe Model (WPM), which correctly predicts the form of tip-to-base conduit widening across the span of plant size, life form, and habitat across the terrestrial plant phylogeny. 相似文献
998.
Francesco Bellandi Fabrizio Cantini Tiziana Pedone Roberto Palchetti Mohamed Bamoshmoosh Roberto Piero Dabizzi 《Clinical cardiology》1995,18(11):631-634
To evaluate the efficacy of propafenone in converting recent-onset atrial fibrillation (AF) lasting <7 days, 182 patients were treated intravenously with propafenone (Group 1, n = 98) and with placebo 0.9% saline solution (Group 2, n = 84) in a double blind study. The treatment was continued until sinus rhythm (SR) was restored, but for no more than 24 h. Eighty-nine patients treated with propafenone (90.8%) and 27 patients treated with placebo (32.1%) responded to the treatment and SR was restored (p < 0.0005). The mean time for SR restoration was 2.51± 2.77 h in Group 1, and 17.15± 7.8 h in Group 2 (p < 0.0005). In both groups the patients in whom SR was not restored (nonresponders) had larger left atrial size and longer duration of AF than responders at the onset of the arrhythmia. Nonresponders in Group 1 showed a decrease in mean ventricular rate (MVR) from 143± 16 to 101± 18 (p < 0.0005), while in the nonresponders in Group 2 no reduction of MVR was observed. Two patients whose SR was restored with propafenone had sinus standstill lasting 3.4 and 3.8 s, respectively. Propafenone used intravenously is an effective, quick, and safe drug for treating AF. Moreover, it significantly reduces MVR in nonresponders. 相似文献
999.
Hegazi RA Mady HH Melhem MF Sepulveda AR Mohi M Kandil HM 《Inflammatory bowel diseases》2003,9(4):230-236
Nonsteroidal anti-inflammatory drugs decrease sporadic colorectal carcinoma and adenomas in patients with familial adenomatous polyposis and in rodent models of sporadic colon cancer and familial adenomatous polyposis. Similarly, selective cyclooxygenase 2 inhibitors decrease adenomas in humans and rodents. However, their effects on chronic colitis and colitis-associated neoplasia are unknown. Interleukin 10-/- mice (C57/B6) were fed regular chow (n = 20) or chow with celecoxib (1,500 ppm, n = 18) or rofecoxib (75 ppm, n = 20) for 12 weeks. Twenty-eight percent of the celecoxib group died versus 5% of the control and rofecoxib groups (p < 0.05 compared with control). Celecoxib and rofecoxib increased the incidence of colitis (26% vs. 92% and 68%, p < 0.01), colitis score (0.4 +/- 0.2 vs. 2.5 +/- 0.3 and 2 +/- 0.4, p < 0.01), aberrant crypt foci (0.5 +/- 0.3 vs. 3.7 +/- 2.6 and 2.8 +/- 0.7, p < 0.01), aberrant crypts per mouse (4.11 +/- 2.1 vs. 41.2 +/- 9.7 and 27.1 +/- 7.5, p < 0.01) and dysplasia (11% vs. 54% and 42%, p < 0.01). Similarly, indomethacin (9 ppm, n = 15) increased colitis score, aberrant crypt foci, and dysplasia after 27 days of treatment. Two selective cyclooxygenase 2 inhibitors exacerbate colitis and premalignant changes in the interleukin 10-/- mouse model of chronic colitis and colitis-associated colon carcinoma. 相似文献
1000.
Safi H Gormus BJ Didier PJ Blanchard JL Lakey DL Martin LN Murphey-Corb M Vankayalapati R Barnes PF 《AIDS research and human retroviruses》2003,19(7):585-595
To characterize the manifestations of coinfection with M. tuberculosis and SIV infection, we studied 12 SIV-infected rhesus monkeys, six of which were infected intrabronchially with a low dose of Mycobacterium tuberculosis H37Rv. In the six coinfected animals, M. tuberculosis antigen-stimulated lung and blood cells produced high concentrations of IFN-gamma but not IL-4 8-16 weeks after infection. Of the three coinfected animals with high levels of plasma viremia, two developed disseminated tuberculosis and the other died of bacterial peritonitis. Of three coinfected animals with moderate levels of plasma viremia, two had no clinical or radiographic evidence of tuberculosis or progressive SIV infection for 6 months after infection. At neuropsy, pulmonary granulomata were observed and acid-fast organisms or M. tuberculosis were present. These clinical, immunologic and pathologic findings are consistent with those in humans with latent tuberculosis infection (LTBI), and suggest that a model of LTBI in SIV-infected primates can be developed. Such a model will permit delineation of the immunologic and microbial factors that characterize LTBI in HIV-infected persons. 相似文献