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排序方式: 共有840条查询结果,搜索用时 15 毫秒
41.
Gordon Cook A John Ashcroft Guy Pratt Rakesh Popat Karthik Ramasamy Martin Kaiser Matthew Jenner Sarah Henshaw Rachel Hall Jonathan Sive Simon Stern Matthew Streetly Ceri Bygrave Richard Soutar Neil Rabin Graham H Jackson the United Kingdom Myeloma Forum 《British journal of haematology》2020,190(2):e83-e86
42.
Saurabh RamBihariLal Shrivastava Prateek Saurabh Shrivastava Jegadeesh Ramasamy 《African health sciences》2014,14(2):487-488
Background
Unsafe abortion refers to a procedure for terminating an unintended pregnancy performed either by persons lacking the necessary skills or in an environment that does not conform to minimal medical standards, or both.Objectives
The objectives of the study are to assess the factors attributing to practice of unsafe abortion and to suggest feasible and cost-effective measures to counter the same.Methods
An extensive search of all materials related to the topic was made using library sources including Pubmed, Medline and World Health Organization. Keywords used in the search include unsafe abortion and unintended pregnancy.Results
Multiple socio-demographic determinants and barriers such as illiterate women, poor socio-economic status, poor awareness about abortion services, associated stigma, and untrained health professionals have been identified resulting in restricted utilization/access of women to safe abortion services. Consequences of unsafe abortion have been alarming, seriously questioning the quality of health care delivery system.Conclusion
Concerted and dedicated efforts of government in collaboration with the private sector, community members and non-governmental organizations are needed to ensure that women have a better access to contraceptives, abortion services, and post-abortion care that are safe, affordable, and free from stigma. 相似文献43.
Jesse Ory Sirpi Nackeeran Udi Blankstein Joshua T. White Ethan Grober Sheldon H. Marks Ranjith Ramasamy 《Canadian Urological Association journal》2022,16(3):E132
IntroductionVasectomy reversal (VR) represents an excellent option for paternity in men who desire to expand their family following vasectomy. Traditional VR via vasovasostomy has a success rate upwards of 90%1,2 but when sperm or sperm parts are not present in vasal fluid, epididymovasostomy (EV) must be performed instead. Our objective was to determine which factors influence success after bilateral EV.MethodsA prospectively maintained database with data from the U.S. and Canada was used to identify men who underwent bilateral EV at time of VR. Success was defined as motile sperm in any postoperative semen analyses. Multivariable logistic regression was used to identify predictors of success.ResultsA total of 200 men had at least one postoperative semen analysis, and 171 men were included in the analysis. Average age was 44.7 years, with average followup of seven months. Median time elapsed between vasectomy and EV was 15 years (interquartile range [IQR] 10–18). Overall success rate was 50%. Despite the study being adequately powered, factors such as years since vasectomy (odds ratio [OR] 1.01, confidence interval [CI] 0.95–1.06), age (OR 0.96, CI 0.91–1.01), intraoperative presence of motile sperm (OR 0.81, CI 0.41–1.62), and epidydimal fluid characteristics did not predict success.ConclusionsBilateral EV at time of VR is successful in 50% of cases in a multi-institutional, North American cohort. Microsurgeons can be reassured that neither time elapsed nor epididymal fluid characteristics negatively impact success rates as long as sperm or sperm parts are present. Surgeons performing VR should be comfortable and prepared to perform EV if indicated. 相似文献
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46.
N Deivanayagam K Nedunchelian S Ramasamy S R SudhandirakannanRatnam 《Indian pediatrics》1992,29(12):1529-1532
We conducted a case control study to identify the risk factors for death among hospitalized children with acute pneumonia at the Institute of Child Health, Madras. All the 70 patients who died of pneumonia constituted the case--patients and 140 children recovered from pneumonia, selected by systematic sampling, during the same period served as controls. By univariate analysis, the risk factors for death in pneumonia observed were associated illnesses--Odds Ratio (OR) 22.2. (95% confidence interval [CI] 9.8-51.4; p = < 0.001); congenital anomalies--OR 10.4 (2.9-37.8; p = < 0.001); severe pneumonia--OR 4.2 (1.2-14.4; p = 0.09); marasmic status--OR 2.9 (1.5-5.7; p = 0.001); age under 6 months--OR 2.8 (1.3-5.7; p = 0.004); and severity of the pneumonia (lobar versus segmental)--OR 2.0 (0.9-4.5; p = 0.09). By logistic regression analysis the following risk factors were significant--associated illnesses. (51.6; 18-146.9; p = < 0.001); age under 6 months (6.5; 2-20.6; p = < 0.001), marasmic status (5.8; 2.2-15.6; p = < 0.001); and congenital anomalies (3.8; 2.0-7.1; p = < 0.001). These risk factors should be kept in mind by the clinicians for appropriate intervention at an earlier stage to minimize death. 相似文献
47.
Relative importance of enhanced glucose uptake versus attenuation of long-chain acyl carnitines in protecting ischemic myocardium 总被引:2,自引:0,他引:2
BACKGROUND: A number of experimental studies have shown that increasing glucose use or decreasing accumulation of long-chain acyl carnitines (LCAC) protect ischemic hearts. METHODS: To evaluate the relative importance of these two strategies in protecting ischemic myocardium, isolated rat hearts (n = 6 in each group) were paced at 300 bpm and subjected to 50 min of low-flow ischemia followed by 60 min of reperfusion. Buffer contained 0.4 m mol/l albumin, 0.4 m mol/l palmitate, and 70 mU/l insulin, and either normal glucose (5 m mol/l) (CON), high glucose (10 m mol/l total) (HG, known to increase glucose use), 5 m mol/l glucose and niacin (10 micromol/l) (NIA, known to increase glucose use and decrease LCAC) or carnitine (10 m mol/l) (CAR, known to increase glucose use and decrease LCAC). Separate groups of hearts were perfused in the presence of 10 micromol/l cytochalasin-B (CB), an inhibitor of insulin-sensitive glucose transporters. RESULTS: Ischemic injury, as assessed by creatine kinase (CK) release was diminished by an average of 50% in HG, NIA, and CAR hearts, and the percentage recovery of left ventricular (LV) function with reperfusion was enhanced by approximately 20% compared with CON hearts (P < 0.05 for each comparison). Cytochalasin-B abolished all of the salutary effects. Long-chain acyl carnitines levels were higher in HG hearts compared with NIA- and CAR-treated hearts ( P < 0.05), but ischemic protection and functional recovery was greater in HG hearts. CONCLUSIONS: The data support the adjunctive use of agents that promote glucose uptake during ischemia and suggest that increasing glucose use is more important than decreasing LCAC in the protection against ischemic injury or in the recovery of contractile function. 相似文献
48.
Portner PM Jansen PG Oyer PE Wheeldon DR Ramasamy N 《The Annals of thoracic surgery》2001,71(1):205-209
BACKGROUND: Cumulative experience with the Novacor wearable electric left ventricular assist system (LVAS) now exceeds 850 recipients. The pump inflow conduit (IFC) has been implicated in embolic complications. METHODS: Clinical outcomes were compared for two IFC designs in a retrospective, nonrandomized, multicenter study. The original IFC (woven, unsupported, crimped polyester: control group) and an alternative IFC (knitted, gelatin-sealed, integrally supported, uncrimped polyester: test group) were utilized upon availability in North American and European centers. Differences in cerebral embolism to 180 days postimplant were analyzed. RESULTS: Four hundred ninety patients implanted between August 1996 and August 1999, were studied. Two hundred eighty-eight received the control IFC and 202 received the test IFC. The groups (control, test) were well matched for age (48, 49 years), etiology (idiopathic 53%[152 of 288], 55% [112 of 202]; ischemic 34% [97 of 288], 33% [66 of 202]) and mean observation time (97, 91 days). The incidence of embolic cerebrovascular accidents (CVA) was 21% (60 of 288) in the control and 12% (24 of 202) in the test group (p = 0.010). Independent risk factors for embolic CVA were found to be preimplant acute myocardial infarction (odds ratio 4.3), age above 50 years (odds ratio 2.1), and ischemic etiology (odds ratio 1.7). There was no difference in survival between the groups (71% [205 of 288], 68% [137 of 202]). CONCLUSIONS: The alternative (test) IFC has significantly reduced the incidence of embolic CVA. This improvement is likely due to increased resistance to deformation at implant, improved neointimal adhesion, and more favorable blood flow characteristics within the conduit. 相似文献
49.
Zinc is necessary for normal membrane function and stability. We postulated that Zn deficiency may disrupt the integrity of the vascular endothelium by decreasing its barrier function. To test this hypothesis, endothelial cells were cultured on polycarbonate filters and exposed to media enriched with either 1% fetal bovine serum (FBS) (low FBS; total Zn, 1.07 mumols/L medium) or 5% FBS (control; total Zn, 2.29 mumols/L) or low FBS plus two supplemental levels of Zn, 3.36 and 5.66 mumols total zinc/L. Endothelial cell barrier function, expressed as albumin transfer across cultured endothelial monolayers, was significantly lower in cultures exposed to low FBS compared with control medium. Supplementation with 5.66 mumols total Zn/L completely restored endothelial barrier function. A divalent cation chelator, 1,10-orthophenanthroline, was used to induce Zn deficiency in vitro. Compared with control cultures, the presence of 1,10-orthophenanthroline in the culture medium resulted in markedly lower endothelial barrier function that was increased by the addition of Zn but not calcium or magnesium. Activity of the membrane-bound zinc-dependent angiotensin-converting enzyme (ACE) was depressed by low zinc medium, whereas membrane-bound Ca(2+)-ATPase and total ATPase were not depressed. Furthermore, cells cultivated in low zinc medium did not have greater cytosolic release of adenine, indicating no increase in cell injury or death. These data suggest that Zn is vital to endothelial cell integrity and that Zn may play an important role in vascular endothelial barrier function. 相似文献
50.