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991.
992.
Edelman  RR; Mattle  HP; Kleefield  J; Silver  MS 《Radiology》1989,171(2):551-556
A technique is described for rapid imaging of blood flow and dynamic measurement of its velocity. The method is a combination of bolus tracking and low-flip-angle gradient-echo cine angiography. This method provides precise determination of velocity with high temporal resolution in a single measurement. Unlike what occurs in phase imaging techniques, flow is displayed directly, eliminating potential errors that result from non-flow-related sources of phase shifts. Manipulation of raw data sets is avoided. Results obtained from a flow phantom, healthy volunteers, and a patient with an aortic aneurysm demonstrate the capability of the technique to track flow at low and high velocities and to differentiate flowing blood from thrombus. Because of its conceptual simplicity, rapidity, and lack of susceptibility to extraneous phase shifts, this technique may prove ideal for in vivo flow measurement and evaluation of flow patterns.  相似文献   
993.

Use of e-cigarettes and other electronic nicotine delivery systems (ENDS) is on the rise. We administered a health needs survey via email to 804 adult primary care and oncology patients at a large urban academic medical center in 2019. We examined differences in e-cigarette use by smoking status, personal history of cancer, alcohol use, and second-hand tobacco smoke exposure. Of the 804 participants, 90 (11.2%) reported ever using e-cigarettes. E-cigarette use was more prevalent in young adults (risk ratio [RR] for 18–24 years: 4.58, 95% confidence interval [95% CI] 2.05, 10.26), current smoking (RR 4.64, 95% CI 1.94, 11.07), very often/often binge drinking (RR 3.04, 96% CI 1.38, 6.73), and?≥?1 smokers in the home (RR 3.90, 95% CI 2.10, 7.23). Binge alcohol consumption and tobacco smoking are associated with increased risk cancer. Inquiries about e-cigarette use among adults 25–40 years present providers the opportunity to also counsel young adult about reducing cancer risk.

  相似文献   
994.
995.
996.
OBJECTIVE: The aim of our study was to determine the prevalence of human immunodeficiency virus-1 (HIV-1) in an infertile population. DESIGN: The study design included a retrospective anonymous survey of clinical data and screening for HIV-1 antibody by enzyme-linked immunoabsorbent assay (ELISA) in stored sera. Samples that were ELISA-positive were further tested by Western blot assay. Frequency distributions were analyzed by Fisher's exact test. SETTING: University tertiary care center. PARTICIPANTS: Based on availability of stored frozen sera, the total study population included 182 of 304 consecutively registered infertile couples. RESULTS: Seventy-five percent of the study population were found to have one or more risk factors for HIV infection. Of the 252 sera tested, 10 were repeatedly reactive by ELISA, and Western blot testing confirmed HIV-1 infection in one woman and two men. CONCLUSIONS: This relatively high HIV-1 seroprevalence (male: 2.6%; female: 0.6%) in a low-middle class infertile population emphasizes the urgent need to implement on-site HIV-infection counseling aimed at preventing the spread of disease to the healthy partner and fetus and to discuss therapeutic and reproductive options.  相似文献   
997.
This study was done to investigate the effects of pentagastrin and of somatostatin analog (SMS 201-995) on growth of CT26 adenocarcinoma of the colon implanted in mice. Eighty Balb C mice were inoculated subcutaneously with 100,000 cells. Four groups of 20 mice each were treated with 0.1 milliliters of saline solution every eight hours; 250 micrograms per kilogram of pentagastrin every eight hours; 100 micrograms per kilogram of SMS 201-995 every 12 hours; 250 micrograms per kilogram of pentagastrin every eight hours, plus 100 micrograms per kilogram of SMS 201-995 every 12 hours. Tumoral weight, volume and deoxyribonucleic acid (DNA) content and mean survival rates were determined for each group. Control mice had tumors weighing 1,619 +/- 179 milligrams, of 1.47 +/- 0.2 milliliters to the third power and with 12.9 +/- 1.1 milligram of DNA, at 30 days after inoculation. The mean survival rate was 42.5 days. Pentagastrin administration increased the three parameters of tumoral growth by 40 percent and reduced survival time to 29.6 days (p < 0.01), while SMS 201-995 inhibited growth by 40 percent and prolonged survival time to 48.5 days (p < 0.01). Simultaneous administration of both peptides had no effects. These data suggest that pentagastrin has a trophic effect and SMS 201-995 an inhibitory effect on CT26 adenocarcinoma in mice.  相似文献   
998.
Clinical intestinal transplantation   总被引:3,自引:0,他引:3  
The advent of tacrolimus allowed clinical intestinal transplantation to become a feasible procedure for patients with irreversible intestinal failure. Over last 5 years, 71 patients underwent intestinal transplantation. Forty-one recipients were children, and 30 recipients were adults. Twenty-five patients received an isolated intestinal graft, 34 patients received a combined liver-intestinal graft, and 12 received a multivisceral graft. The colon was included the intestinal graft in 29 patients. One-year, 2-year, and 4-year actuarial patient survival is 72%, 57%, and 45%, respectively. Our experience has shown that infectious, and immunological problems have caused significant morbidity and mortality. In this paper, we present our clinical experience and overview with intestinal transplantation.  相似文献   
999.
A population-based case control study was conducted to ascertain whether the process of primary care can be a determinant of infant mortality due to Acute Respiratory Infection (ARI). Cases were 118 infants who died from ARI, individually matched with 118 infants who suffered an ARI episode and recovered. Information was gathered through interviewing mothers. Study variables were assembled into five subsets: children's characteristics; mothers' characteristics; access to medical services; process of primary care, and; sociodemographic variables. An index per subset was built to analyze the independent influence of each on ARI death risk. The index was constructed upon the weighted sum of the adjusted odds ratios (OR) within each subset. Then, the values of each index were collapsed into high/low values with the 50 percentile as a cut-off value. Next, by means of a conditional logistic regression procedure, an explanatory model of ARI mortality was obtained. The final multivariate model included the indexes that showed an independent effect: I) Process of care (OR 9.68, CI 95% 3.59-26.1): inadequate referral, attention provided by more than one physician and being attended by a private physician; II) children's characteristics (OR 7.22, CI 95% 2.35-22.2): perinatal history, lack of breast-feeding and incomplete immunization scheme; III) access to medical services (OR 5.27, CI 95% 2.02-13.7): geographic and economic barriers, lack of confidence in public health services, and; IV) mothers' characteristics (OR 4.03, CI 95% 1.18-13.8), mainly represented by untimely care seeking. We conclude that the management of the disease is a key determinant in which factors relating to the mother and the health services are strongly related. Our study reveals untimely care seeking, difficult access and inadequate disease treatment as important factors which deserve careful attention in the future. We also confirm the importance of biological determinants previously described. A main strategy to reduce infant mortality due to ARI should be to encourage training of primary care physicians, including private practitioners, focused on providing effective case management and emphasizing the education to mothers.  相似文献   
1000.
In many studies in which the relationship between blood pressure and blood lead level has been examined, investigators have found significant--but small--associations. There was only one previous report of a significant association of blood lead with blood pressure in pregnant women. We measured blood lead level and sitting blood pressure of 1,627 women in their third trimester of pregnancy. We eliminated subjects with known causes of hypertension. Most women (98.4%) were normotensive. We controlled for body mass index, age, and stress--among other factors--and constructed multiple-regression models of lead association with diastolic and systolic blood pressures. Immigrants (73% of total) had significantly higher blood lead levels and different blood pressures than nonimmigrants, suggesting that analysis be stratified by "immigrant, nonimmigrant" status. Positive relationships between blood lead level and blood pressure were found only for immigrants (p < or = .001). From the 5th to 95th blood-lead percentiles (0.9-6.2 microg/dl) in immigrants, systolic blood pressure increased 2.8 mm Hg, and diastolic blood pressure increased 2.4 mm Hg. Higher prior lead exposure of immigrants (97.7% from Latin countries) than nonimmigrants might explain the differential effect of these low levels of blood lead on blood pressure in nonimmigrants. Perhaps some immigrants are at higher risk than nonimmigrants for lead-associated elevated blood pressure during pregnancy, despite blood lead levels within the currently considered acceptable range.  相似文献   
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