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81.
Pulmonary hypertension (PH) produces strain followed by hypertrophy and later dilatation of the right ventricle (RV) and pulmonary artery. The signs and symptoms are nonspecific. There is a need for a noninvasive sensitive way to diagnose PH. The purpose of this study is to evaluate phase abnormalities in radionuclide MUGA studies of patients with referred diagnosis of PH. In a retrospective analysis of 44 patients who had a radionuclide multigated study (MUGA) and contrast ventriculography (CV), 19 had high mean pulmonary pressure (over 20 mmHg) and a high pulmonary vascular resistance index (over 2.0). In 15 patients, a delayed phase segment in the RV corresponding to the pulmonary infundibulum and pulmonary conus was noted The Pulmonary Tongue sign (PT), 12 had PH (True positive) and 3 did not (false positive) on CV. No PT was seen in the remaining 29 patients, only 7 of them had PH (False negative). The sensitivity, specificity and accuracy of the PT sign in detecting PH was 80%, 72% and 77% respectively. The number of patients was too small to calculate the correlation of the grade of PT with the severity of PH. We conclude that The Pulmonary Tongue sign on a MUGA study is clinically useful in detecting PH.This project is supported by research project MLNO13 and funded by research Council, Kuwait University  相似文献   
82.
The excretion, tissue distribution, and binding of [14C]-formaldehyde were studied at different time intervals in male rats following a single intraperitoneal injection of 72 mg CH2O (14.7 Ci)/ kg body weight. Within 30 min, 10% of the total dose was recovered in expired air as14CO2 and by the end of 72 hr, 41% of the administered dose was eliminated through expired air. The total elimination of14CH2O activity in urine and feces in 72 hr was 15%. Erythrocytes retained significant amounts of radioactivity, even at the end of 72 hr. Substantial levels of radioactivity were detected in most tissues one hr after administration, indicating a fast absorption and rapid distribution. Subcellular fractionation of the tissues showed that the highest levels of relative percent binding was in the microsomal fraction, whereas cytosol fractions contained lowest levels of bound radioactivity. DNA, RNA, protein and lipid fractions of liver and spleen tissues showed significantly elevated levels of14C-incorporation as compared to other tissues. Thein vivo incorporation of14C-activity showed an increased association of14CH2O with RNA in all the tissues. The maximum registration of radioactivity in RNA was at 48 hr after administration. Significantly higher amounts of14C-activity were registered in DNA of all tissues. The maximum registration of radiolabel in DNA of most tissues was at 12 hr after the14CH2O administration. The liver DNA showed maximal levels at 3 hr with a second peak at 48 hr.Substantial amounts of bound radioactivity in nucleic acids of all the tissues were observed even 72 hr after dosing. The relationship between macromolecular association and formaldehyde toxicity has been discussed.  相似文献   
83.
Summary A new synthetic tripeptide (p-F-Phe-m-bis-(2-chloroethyl)amino-Phe-Met ethoxy HCl), PTT.119, was demonstrated to have significant cancericidal activity against seven in vitro tumor cell lines of different origins and etiologies and against primary human AMML, ALL, and hairy cell leukemias. Viabilities of each murine tumor and rabbit, marmoset, and human leukemia and lymphoma line were significantly reduced by treatment with 1–50 g PTT.119 in media containing serum. Continuous 24-h exposure or pulse treatment as short as 15 and 30 min with the tripeptide resulted in irreversible damage to the tumor cells. Under identical treatment conditions, freshly isolated human leukemic cells, particularly ALL lymphoblasts, were even more susceptible to PTT.119 than any of the tested tumor cell models.Examination of the parameters of PTT.119 activity revealed that reductions of tumor cell survival were dependent on the concentration of the tripeptide. Prolongation of PTT.119 exposure from 15 min to 24 h increased the rates of tumor cell death but did not proportionally reduce the numbers of surviving cells. Assessment of tumor cell viabilities for 5 consecutive days following pulse exposure to PTT.119 demonstrated increasing reductions in tumor cell survival, which were greatest 5 days after treatment with the tripeptide.The cancericidal activity of PTT.119 was compared with its three parental components either as individual agents or as a mixture. Both the alkylator moiety, m-sarcolysin (m.L.SL) alone or together with p-fluoro-phenylalanine and l-methionine ethoxy HCl, and l-PAM (l-phenylalanine mustard), the p-isomer of m.L.SL, were 1.5- to 3-fold less cytotoxic to L1210 leukemia and MJY-alpha mammary tumor cells than PTT.119. Covalent linkage of the amino acid residues to m.L.SL yielded a molecule with greatly augmented cancericidal activity capable of acting against a broad spectrum of tumor cells.  相似文献   
84.

This paper analyzes the impact of mental health treatment on suicide attempts. While prior work demonstrates the effectiveness of mental health treatment at reducing suicide risk, few studies examine nationally representative populations or use broad measures of access to mental health services. A methodological problem can arise in studies of mental health treatment and suicidal behavior because a suicide attempt can result in the use of more mental health services. Using nationally representative survey data combined with national estimates of provider availability, this paper employs a methodological correction to address that potential problem of reverse causation. This paper uses measures of the density of health care providers in an area as statistical instruments for use of mental health treatment in an analysis of the impact of mental health treatment on suicide attempts. This study finds that mental health treatment significantly reduces suicide attempts.

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85.
BackgroundIn the context of the opioid epidemic, a limited but growing body of literature has found state medical marijuana laws (MMLs) to be associated with lower levels of opioid prescribing. However, robust evidence linking state MMLs with individual-level opioid-related outcomes is lacking, particularly among women. This finding is especially true for pregnant and parenting women, who have been disproportionately affected by the opioid crisis.MethodsUsing data drawn from the 2002–2014 National Survey on Drug Use and Heath, the study uses a difference-in-differences estimation strategy to compare opioid-related outcomes (opioid misuse initiation, opioid misuse in the past month and past year, and opioid use disorder) among all women, pregnant women, and parenting women in states with and without MMLs (before and after implementation). The study also investigates the impact of MMLs on marijuana use and marijuana use disorder.ResultsThe findings indicate that MMLs were not associated with opioid misuse, opioid misuse initiation, or opioid use disorder among all women, pregnant women, and parenting women. These laws were, however, positively correlated with marijuana use and marijuana use disorder among all women and women with children. In addition, MMLs were associated with an increase in the frequency of opioid misuse for pregnant women and a decrease in the frequency of opioid misuse for parenting women.ConclusionsThis finding suggests that, although medical marijuana may be viewed by some as a substitute for opioid analgesics, MMLs may not be an effective policy tool to tackle the opioid epidemic among women, especially pregnant and parenting women.  相似文献   
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BackgroundSquare knots can be difficult to construct in deep body cavities. The reversing half-hitch alternating post (RHAP) surgical knot has noninferior tensile strength and performance characteristics in deep body cavities. We compared the enterotomy repairs of novice learners in simulated deep body cavities using RHAP versus square knots after proficiency-based training.MethodsUndergraduate students were randomized to RHAP (n = 10) or square knot (n = 10) groups and trained to defined proficiency. They then performed hand-sewn enterotomy repairs of cadaveric porcine small bowels on flat surfaces and in simulated deep body cavities. We recorded time to knot-tying proficiency and to enterotomy repair, and burst pressures for the repair.ResultsMean time-to-proficiency in knot tying was equivalent between the RHAP and square knot groups (23 [standard deviation (SD) 3] v. 21 [SD 2] min, p = 0.33). Mean time for enterotomy repair in deep cavities was shorter for the RHAP group (16 [SD 2] min v. 21 [SD 1] min, p = 0.02). Mean burst pressures for enterotomy repair were equivalent on flat surfaces (128 [SD 41] v. 101 [SD 36] mm Hg, p = 0.31), and were significantly higher for the RHAP group in simulated deep body cavities (32 [SD 13] v. 105 [SD 37] mm Hg, p = 0.05).ConclusionThe RHAP knots appear to have superior performance versus square knots when tied in a deep body cavity by novice learners. Future work should focus on demonstrating the clinical relevance and broad utility of the RHAP knot in abdominal surgery. Both knot types should be taught to novice learners.  相似文献   
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90.
BackgroundOrgan transplantation is considered one of the greatest advances of modern science, and it has given many patients a renewed lease on life. The demand for organs far exceeds the supply. Health professionals are fundamental in the process of organ procurement.ObjectiveTo assess the attitude, willingness, and associated factors in organ donation among health professionals of Gondar, Ethiopia.MethodsOur cross-sectional study was conducted among 382 randomly selected health professionals in Gondar using a self-administered questionnaire. Multivariable logistic regression analysis was applied to analyze the data.ResultsAmong health professionals, 79.1% had favorable attitude toward organ donation and 74.6% were willing to donate their organs. After adjusting for covariates, the odds of having a favorable attitude about organ donation were 3.2 and 11.9 times higher in the professions of laboratory technologists and medical doctors, respectively. By keeping all other variables constant, attitude was found to be positively associated with awareness (adjusted odds ratio [aOR] 12.74, 95% confidence interval [CI] 3.71-43.8) and being a member of the Red Cross Association (aOR 5.24, 95% CI 1.46-18.96). Willingness was positively associated with awareness (aOR 6.25, 95% CI 2.0-19.53), a member of the Red Cross Association (aOR 5.09, 95% CI 1.5-17.22), a laboratory technologist (aOR 3.57, 95% CI 1.37-9.29), and a medical doctor (aOR 6.52, 95 % CI 1.93-22.01).ConclusionsThe main findings indicated that the majority of health professionals in Gondar had a favorable attitude toward organ donation and were willing to donate their organs in times of need.  相似文献   
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