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排序方式: 共有1143条查询结果,搜索用时 15 毫秒
71.
72.
Babiarz LS Yousem DM Wasserman BA Wu C Bilker W Beauchamp NJ 《AJNR. American journal of neuroradiology》2003,24(5):872-877
BACKGROUND AND PURPOSE: The relevance of cavernous carotid artery calcification on unenhanced CT scans of the brain has recently been investigated against the backdrop of the widespread implementation of coronary artery calcification scoring. We sought to determine whether the degree of cavernous carotid artery calcification correlated with scores of white matter hyperintensity seen on MR images. In so doing, we sought to establish a relative risk for future stroke on the grade of carotid calcification. METHODS: Neuroradiologic findings in 187 patients who underwent CT and MR imaging examinations within 1 month of each other were retrospectively reviewed. The degree of circumferential calcification and thickness of calcification were graded for the cavernous carotid arteries on the basis of CT findings. Using the scale developed by the Cardiovascular Health Study, the white matter was graded for degree of disease on the basis of MR findings. Correlation tests and regression analyses were performed to determine the impact of age, race, and sex on results. RESULTS: Although the cavernous carotid calcification scores and the MR imaging white matter scores showed good correlation (P <.001), the effect was mediated by age. With age factored in as a covariant, no correlation was shown between CT calcification scores and MR imaging white matter scores. Sex had no effect, but African American study participants had worse MR imaging white matter scores than did white participants. CONCLUSION: After adjusting for age, cavernous carotid calcification grades and MR imaging white matter scores do not show a significant correlation. The relative risk for future stroke cannot be predicted from cavernous carotid calcifications. 相似文献
73.
Witek A 《Ginekologia polska》2000,71(2):98-106
In 1996 Kuiper et al. have cloned a novel member of the nuclear receptor superfamily. The cDNA of clone 29 was isolated from a rat prostate cDNA library. The new receptor was highly homologus to the rat estrogen receptor protein, particularly in the DNA-binding domain. New protein consists of 485 amino acid residues and its molecular weight is 54.2 kDa. Like other steroid receptors, ER beta has six regions, A-F. A novel receptor is expressed in the secretory epithelial cells of the prostate and also in the granulosa cells of the ovary. Differences in the ligand-binding properties and transactivation function on target genes may exist. The tissue distribution and relative level of ER alpha and beta expression seems to be quite different, i.e. moderate to high expression in uterus, testis, pituitary, ovary, kidney, and adrenal for ER alpha and prostate, ovary, lung, bladder, brain, uterus and testis for ER beta. The differences between the receptors subtypes in relative ligand binding affinity and tissue distribution could contribute to the selective action of ER aginists and antagonists in different tissues. These new findings bring up many questions. The most intriguing is how has this second ER eluded investigators for so many years? Perhaps a limited number of estrogen target tissues were screened. The biological significance of the existence of two different ERs is at this moment unclear. Perhaps the existence of two ERs subtypes provides an explanation for the selective actions of estrogens in different target tissues. 相似文献
74.
R B Turner M T Wecker G Pohl T J Witek E McNally R St George B Winther F G Hayden 《JAMA》1999,281(19):1797-1804
CONTEXT: Attachment of most rhinovirus subtypes to cells depends on a cellular receptor, the intercellular adhesion molecule 1 (ICAM-1). A recombinant soluble ICAM-1 (tremacamra, formerly BIRR 4) has shown possible efficacy in early studies. OBJECTIVE: To determine the efficacy and safety of intranasal administration of tremacamra in experimental rhinovirus colds in humans. DESIGN: Four randomized, double-blind, placebo-controlled trials conducted in January to March 1996. SETTING AND SUBJECTS: Volunteers between the ages of 18 and 60 years who had an antibody titer of 1:4 or less to the challenge virus. Subjects were isolated in a hotel room during study days 0 to 8; symptoms were recorded through day 14. A total of 198 subjects were randomized, of whom 196 received drug or placebo and were included in the safety analysis. A total of 177 subjects were included in the efficacy analysis. INTERVENTIONS: Tremacamra or placebo was given beginning 7 hours before inoculation with rhinovirus type 39 (preinoculation studies) or 12 hours after (postinoculation studies). Tremacamra as an inhaled solution or as a powder (each given preinoculation and postinoculation for a total of 4 studies) and placebo were given in 6 doses at 3-hour intervals daily during days 1 through 7. Recipients of active treatment received 367 microg of tremacamra per nostril per dose for a total of 4.4 mg/d. MAIN OUTCOME MEASURES: Effect of tremacamra on infection, as determined by virus isolation and seroconversion, and on illness, as determined by symptom scores, clinical colds, and nasal mucus weights. Treatment-by-study interaction was not significant, so results were pooled for the main analysis. RESULTS: A total of 88 (92%) of the 96 subjects in the placebo groups and 69 (85%) of the 81 subjects in the active treatment groups were infected (P=.19). For placebo vs tremacamra, respectively, the total symptom score (+/- 95% confidence interval [CI]) was 17.6 (+/- 2.7) vs 9.6 (+/- 2.9), the proportion of clinical colds was 64/96 (67% +/- 9%) vs 36/81 (44% +/- 11%), and the nasal mucus weight was 32.9 (+/- 8.8) g vs 14.5 (+/- 9.4) g (P<.001 for all comparisons). Tremacamra was not associated with adverse effects or evidence of absorption through the nasal mucosa and did not interfere with development of neutralizing antibody. CONCLUSION: Tremacamra reduced the severity of experimental rhinovirus colds. Whether tremacamra will be useful clinically will require further study. 相似文献
75.
Residual HIV-1 RNA in Blood Plasma of Patients Taking Suppressive Highly Active Antiretroviral Therapy 总被引:19,自引:0,他引:19
76.
Zusammenfassung: 106 junge Mastbullen, bei welchen eine Trichophytose festgestellt wurde, wurden mit Diethanolamin in Form einer Salbe behandelt. Nach 14tägiger, 21tägiger und 28tägiger Behandlung wurden jeweils 64,1%, 87,7% and 95,2% der Here als ausgeheilt erkannt. Daraus ist ersichtlich, daß sich Diethanolamin zur Behandlung von mykotischen Erkrankungen eignet. Summary: 106 young bulls with ringworm were treated with an ointment containing diethanolamine. After 14, 21 and 28 days of application of the ointment 64,1%, 87,7% and 95,2% of the animals were cured, respectively. The results of these studies demonstrate the usefulness of diethanolamine in curing mycotic diseases. 相似文献
77.
J P Dubiel K Kawecka-Jaszcz J Kocemba D Czarnecka T Grodzicki M Skoczen A Skalska J Witek 《Journal of human hypertension》1990,4(4):410-414
The acute hypotensive effect of nifedipine was evaluated, and the possibility of its long-term use in hypertensives over 60 years of age was studied. Sublingual nifedipine in a dose of 20 mg was given to 28 patients, mean age 73.1 yrs, and blood pressure, heart rate, and plasma drug concentration were monitored at 15 min, and every 30 min thereafter for 3 hrs. Systolic and diastolic blood pressure decreased at 15 min by 22.1 and 7.0 mmHg, respectively, reaching a maximal decrease two hours after drug administration. The decrease in blood pressure level did not correlate with nifedipine plasma concentration, but only with the initial systolic blood pressure. Long-term treatment with nifedipine was initiated in 60 patients, with 45 patients completing the study. Mean age was 66.2 years. An initial dose of 30 mg daily had to be increased to 60-80 mg in one-third of the patients. Monotherapy was not satisfactory in some patients. Blood pressure gradually decreased from 173/99 to 148/85 mmHg at three months, and to 141/84 mmHg at six months. Drug tolerance was fairly good. Nifedipine was withdrawn due to a considerable increase in heart rate in three patients and skin allergy in one. The most frequent adverse symptoms were: rash, headache, and leg oedema. Laboratory tests revealed no changes in urea and creatinine, and an increase in fasting glycaemia. Lipid parameters did not change significantly. These data proved that a single dose of 20 mg of nifedipine produced therapeutic plasma concentration of the drug and good hypotensive effect, positively correlating with initial systolic blood pressure.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
78.
Pawel Gawlowski Jacek Smereka Marcin Madziala Lukasz Szarpak Michael Frass Oliver Robak 《The American journal of emergency medicine》2017,35(3):484-487
Introduction
Endotracheal intubation (ETI) using a Macintosh laryngoscope (MAC) requires the head to be positioned in a modified Jackson position, slightly reclined and elevated. Intubation of trauma patients with an injured neck or spine is therefore difficult, since the neck usually cannot be turned or is already immobilized in order to prevent further injury. The iGEL supraglottic airway seems optimal for such conditions due to its blind insertion without the need of a modified Jackson position.Methods
Prospective, randomized, crossover study in 46 paramedics. Participants performing standard intubation and blind intubation via iGEL supraglottic airway device in three airway scenarios: Scenario A – normal airway; Scenario B - manual inline cervical immobilization, performed by an independent instructor; scenario C: cervical immobilization using a standard Patriot cervical extraction collar.Results
In Scenario A, nearly all participants performed ETI successfully both with MAC and iGEL (100% vs. 95.7%). The time to intubation (TTI) using the MAC and iGEL amounted to 19 [IQR, 18–21]s vs. 12 [IQR, 11–13]s (P < 0.001). Head extension angle as well as tooth compression were significantly better with the iGEL compared to the MAC (P < 0.001). In scenario B and C, the results with the iGEL were significantly better than with MAC for all analyzed variables (TTI, success of first intubation attempt, head extension angle, tooth compression and VAS scores).Conclusion
We showed that blind intubation with the iGEL supraglottic airway was superior to ETI performed by paramedics in a simulated cervical immobilization scenario in a manikin in terms of success rate, time to definite tube placement, head extension angle, tooth compression, and rating. 相似文献79.
Jacek Smereka Lukasz Szarpak Adam Smereka Steve Leung Kurt Ruetzler 《The American journal of emergency medicine》2017,35(4):604-609
Background
The impact of high-quality chest compressions during CPR for the patients' outcome is undisputed, as it is essential for maintaining vital organ perfusion. The aim of our study is to compare the quality of chest compression (CC) and ventilation among the two current standard techniques with our novel “nTTT” technique in infant CPR.Methods
In this randomized crossover, manikin trial, participants performed CCs using three techniques in a randomized sequence: standard two finger technique (TFT); standard two thumb technique (TTHT), and the ‘new two-thumb technique’ (nTTT). The novel method of CCs in an infant consists in using two thumbs directed at the angle of 90° to the chest while closing the fingers of both hands in a fist.Results
Median depth compression using the distinct chest compression techniques varied and amounted to 26 [IQR, 25–28] mm for TFT, and 39 [IQR, 39–39] mm for TTHT as well as for nTTT. Best percentage of fully released compressions were received using TFT (100[100 ? 100] %), then in the case of nTTT (99[98–100] %), and the worst in situation where TTHT (18[14–19] %). was used. The fastest chest compression rate was achieved with TFT (134[IQR, 129–135]/min) and the slowest when using nTTT (109 [IQR, 105–111]/min).Conclusions
We found that our new nTTT technique's performance, in terms of compression depth, hands-off time, and ventilation quality, is comparable to the current standards. Based on our findings of this initial manikin study, the nTTT technique is superior to TFT in many of parameters that are vital to a quality chest compression during pediatric CPR. 相似文献80.
Iwona Wybranska Malgorzata Malczewska-Malec Lukasz Partyka Beata Kiec-Wilk Katarzyna Kosno Iwona Leszczynska-Golabek Anna Zdzienicka Anna Gruca Malgorzata Kwasniak Aldona Dembinska-Kiec 《Clinical chemistry and laboratory medicine》2007,45(9):1124-1132
BACKGROUND: New tools to identify genotype-phenotype interactions need to be described and implemented. The aim of this study was to identify correlation between the risk originating from gene variation and diet-dependent development of insulin resistance. METHODS: Insulin output in terms of area under the curve after an oral glucose tolerance test (AUC Ins OGTT) and lipid tolerance tests (AUC Ins OLTT) were measured in 167 overweight/obese patients. Estimation of the 18 common gene polymorphisms for obesity risk and standard phenotyping were performed. RESULTS: Insulin output (AUC Ins OGTT) correlated strongly between both insulin treatments across the whole group. However, within the genotype sub-groups, correlation was lower or did not exist. Using a nutrient-induced insulin output ratio (NIOR), calculated as AUC Ins OLTT/AUC Ins OGTT, values ranged from 0.42 to 5.83 and correlated significantly with body mass index (BMI) and leptin, but not with age, gender, waist-to-hip ratio (WHR) and homeostasis model assessment of insulin resistance (HOMA-IR) or plasma adiponectin. High NIOR was found in a subgroup of carriers of rare allelic variants of genes characteristic for poorer tolerance to lipids in the diet. Low NIOR values were found within a sub-group with rare genetic variants regulating carbohydrate metabolism. Thus, the new insulin index NIOR may distinguish gene variant carriers into groups of glucose- or lipid-sensitive phenotypes. CONCLUSIONS: We suggest that the OLTT/OGTT insulin output ratio (NIOR) may be predictive for identifying individuals who are phenotypically susceptible to insulin resistance in response to high fat or carbohydrate in their habitual diet. 相似文献