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1.
2.
Rolando Barbucci Mario Casolaro Mila Nocentini Gianna Reginato Paolo Ferruti 《Macromolecular chemistry and physics.》1986,187(8):1953-1962
Two linear vinyl polymers carrying amido and primary amino groups in the side chains were synthesized and characterized. Their behaviour in aqueous solution was investigated by potentiometric, viscometric and calorimetric techniques. In both cases, the basicity constants show a linear dependence on the degree of protonation α, while the enthalpy values of protonation do not. The thermodynamic results demonstrate the important role of hydrophobic interactions on the protonation process. 相似文献
3.
O. John Ma MD Michael P. Kefer MD James R. Mateer MD RDMS Beth Thoma MD 《Academic emergency medicine》1995,2(7):581-586
Objective: To compare the sensitivities, specificities, and accuracies between a single-view ultrasonography (US) technique and a multiple-view technique for identifying hemoperitoneum in multiple-trauma patients.
Methods: Data from a prior prospective study of US for trauma diagnosis at a level I trauma center were retrospectively analyzed. A convenience sample of adult patients (≥ 18 years of age) who had presented with major blunt or penetrating torso trauma and had undergone rapid trauma US examinations to detect hemoperitoneum were reviewed. The US interpretations by emergency physicians had been recorded prior to obtaining other diagnostic tests. Five views were evaluated, including the right intercostal oblique view examining Morison's pouch. Evidence of free intraperitoneal fluid by exploratory laparotomy, CT, or diagnostic peritoneal lavage (DPL) was used as the criterion standard.
Results: Of the 245 patients entered into the study, 37 had free intraperitoneal fluid, confirmed by CT, DPL, or exploratory laparotomy. With the multiple-view technique, US was 87% (95% CI = 71%, 96%) sensitive, 100% (95% CI = 97%, 100%) specific, and 98% (95% CI = 95%, 100%) accurate. The single-view technique, evaluating only Morison's pouch, was 51% (95% CI = 34%, 68%) sensitive, 100% (95% CI = 98%, 100%) specific, and 93% (95%. CI = 89%, 96%) accurate.
Conclusions: An initial trauma US examination using a multiple-view technique is more sensitive than that using a single-view technique for detecting hemoperitoneum in trauma patients. 相似文献
Methods: Data from a prior prospective study of US for trauma diagnosis at a level I trauma center were retrospectively analyzed. A convenience sample of adult patients (≥ 18 years of age) who had presented with major blunt or penetrating torso trauma and had undergone rapid trauma US examinations to detect hemoperitoneum were reviewed. The US interpretations by emergency physicians had been recorded prior to obtaining other diagnostic tests. Five views were evaluated, including the right intercostal oblique view examining Morison's pouch. Evidence of free intraperitoneal fluid by exploratory laparotomy, CT, or diagnostic peritoneal lavage (DPL) was used as the criterion standard.
Results: Of the 245 patients entered into the study, 37 had free intraperitoneal fluid, confirmed by CT, DPL, or exploratory laparotomy. With the multiple-view technique, US was 87% (95% CI = 71%, 96%) sensitive, 100% (95% CI = 97%, 100%) specific, and 98% (95% CI = 95%, 100%) accurate. The single-view technique, evaluating only Morison's pouch, was 51% (95% CI = 34%, 68%) sensitive, 100% (95% CI = 98%, 100%) specific, and 93% (95%. CI = 89%, 96%) accurate.
Conclusions: An initial trauma US examination using a multiple-view technique is more sensitive than that using a single-view technique for detecting hemoperitoneum in trauma patients. 相似文献
4.
The use of deep inspiration preceding the valsalva maneuver and rapid expiration in color doppler imaging of the lower extremity veins 总被引:1,自引:0,他引:1
Jing Gao MD Elias Kazam MD William Rubenstein MD Joseph P. Whalen MD Tom Hom RDMS RT 《Clinical imaging》1993,17(4):266-268
Deep inspiration preceding Valsalva maneuver and rapid expiration immediately following it (DIVE) enhance venous blood flow on color Doppler flow imaging (CDI). The effect of DIVE was assessed in 115 consecutive lower extremity examinations. Of these, 95 or 115 (83%) had negative CDI sonograms, and 20 of 115 (17%) had partially (six of 115) or completely (14 of 115) occluding deep vein thrombosis. DIVE enhanced venous blood flow in 68% of the negative cases, resulting in transient venous distention, and/or more complete color filling, and/or greater spectral flow velocities. The 14 cases with completely occluding thrombi showed no response to DIVE. Six cases with partially occluding thrombi showed moderate to mild response to DIVE, with improved color delineation of the residual patent lumen around the thrombus. The authors conclude that DIVE facilitates deep venous CDI, especially when compression cannot be used to augment venous flow. 相似文献
5.
N. Matamoros Florí J. Mila Llambi T. Español Boren S. Raga Borja G. Fontan Casariego 《Journal of clinical immunology》1997,17(4):333-339
The Spanish Registry for Primary Immunodeficiency Diseases (REDIP) was organized in 1993. One thousand sixty-nine cases of primary immunodeficiency diseases (PID) were registered in patients diagnosed between January 1980 and December 1995. PID diagnosis was made according to the World Health Organization criteria. The most frequent disorders were IgA deficiency (n = 394) and common variable immunodeficiency (n = 213), followed by severe combined immunodeficiency (n = 61), C1 inhibitor deficiency (n = 52), X-Iinked agammaglobulinemia (n = 49), IgG subclass deficiency (n = 48), and chronic granulomatous disease (n = 32). A comparative study between REDIP and data recently obtained from the European registry (ESID Report, 1995) revealed important differences between phagocytic disorders and complement deficiencies reported in both registries, 4.9 vs 8.7 and 6.0 vs 3.6, while percentages of predominantly antibody deficiencies and T cell and combined deficiencies concurred with those reported in the European registry, 69.3 vs 64.7 and 14.7 vs 20.2, respectively. The heterogeneous nature of the geographical distribution of cases submitted may indicate underdiagnosis of PID in some country areas; surprisingly, the interval between the onset of clinical symptoms and diagnosis was significant, even in immunodeficiency diseases, such as IgA deficiency, which are easy to diagnose. 相似文献
6.
7.
8.
Rennert G Almog R Tomsho LP Low M Pinchev M Chaiter Y Bonner JD Rennert HS Greenson JK Gruber SB 《Diseases of the colon and rectum》2005,48(12):2317-2321
PURPOSE The probability of colorectal cancer is moderately increased among carriers of the APC I1307K polymorphism. However, it is not known if endoscopic surveillance of this high-risk group is warranted. The prevalence
of polyps and adenomas in specimens of colorectal cancer who are carriers and noncarriers of the APC I1307K polymorphism is compared.
METHOD Prevalence of adenomatous polyps in the pathology specimens of the study participants, stratified by their APC I1307K polymorphism status, was studied in 900 consecutive cases of colorectal cancer diagnosed in northern Israel between
1998 and 2002, within the framework of a population-based, case-controlled study (MECC Study).
RESULTS The APC I1307K mutation was detected in 78 colorectal cancer cases (8.7 percent) of the study population. Prevalence was higher among
Ashkenazi Jews (11.2 percent) than among non-Ashkenazi Jews (2.7 percent) or Arabs (3.1 percent). After adjustment for age,
APC I1307K carriers were significantly more likely than noncarriers to have polyps in their surgical specimen (51.3 percent vs. 32.6 percent, P = 0.002). Adenomas with a tubular component (either tubular adenomas or tubulovillous adenomas), but not villous adenomas,
were significantly more frequent among carriers (37.2 percent vs. 23.6 percent, P = 0.005).
CONCLUSION Together with former evidence of I1307K being a risk factor for colorectal cancer, these data suggest that colonoscopic surveillance
for colorectal adenomas and cancer may be warranted in I1307K carriers, even in the absence of other identifiable risk factors.
Supported by the National Institutes of Health grant RO1-CA81488 to S.B.G. and G.R. 相似文献
9.
We describe a rare giant placental chorioangioma in a patient who had a favorable outcome with close prenatal surveillance in a 28‐year‐old primigravida who was referred to our clinic for ultrasound evaluation of a suspected placental mass at 23 weeks' gestation. A detailed ultrasound scan revealed a well‐circumscribed, echogenic lesion measuring 11.0 × 10.3 × 7.3 cm and protruding into the amniotic cavity. A diagnosis of placental chorioangioma was made and intensive prenatal surveillance was scheduled. A small‐for‐gestational age (2,325 g) but normal female neonate was delivered at 37 weeks by cesarean section and discharged from hospital on the second day of the delivery. A giant chorioangioma may not cause any adverse effect to the fetus and may not require any medication or invasive intervention. © 2014 Wiley Periodicals, Inc. J Clin Ultrasound 43 :254–256, 2015 相似文献
10.
Flora Maria Lorenzo Fortes Ney Boa Sorte Victor D Mariano La la D Andrade Fernanda A Oliveira Monique CA Santos Cl udia Ivanilda N dos Santos Catharina A Passos Mila P Pacheco Valdiana C Surlo Neog lia P de Almeida Jaciane AM Fontes r a M Pimentel Raquel Rocha Genoile Oliveira Santana 《World journal of gastroenterology : WJG》2020,26(44):6993-7004
BACKGROUNDThere has been an increase in cases of inflammatory bowel disease (IBD) in recent years. There is also greater access and availability of immunosuppressive and biological agents, which increase the risk of opportunistic infection despite improving the quality of life and promoting mucosal healing. Tuberculosis (TB) remains a public health problem, and it has a high incidence in several countries. Therefore, knowledge of the risk of developing TB in patients with IBD is important.AIMTo evaluate the risk of active TB in patients with IBD under treatment from an endemic area in Latin America.METHODSA standard questionnaire included demographic variables, clinical aspects of IBD disease, history of active TB during treatment, active TB characteristics and evolution, initial screening and results and time from the start of anti-tumor necrosis factor alpha (TNFα) to TB development.RESULTSAzathioprine, anti-TNFα and the combination of these two drugs were associated with a higher risk of active TB incidence. The TNFα blockers increased the relative risk of developing active TB compared to other treatments. All four multivariable models showed that the use of TNFα blockers alone or in combination with azathioprine was an important risk factor for the incidence of active TB. After adjustment for sex, age, type of IBD and latent TB, anti-TNFα with azathioprine increased the relative risk to 17.8 times more than conventional treatment. Late TB, which was diagnosed 3 mo after the start of anti-TNFα, was the most frequent.CONCLUSIONTreatment with anti-TNFα increased the risk of active TB in IBD patients from an endemic area in Latin America. This risk was increased when anti-TNFα was combined with azathioprine. The time from the beginning of the treatment to the active TB diagnosis suggests a new TB infection. 相似文献