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121.
C M Tracy J F Swartz P Karasik A Solomon R D Fletcher 《Journal of electrocardiology》1992,25(1):65-70
A 27-year-old woman was admitted to the Georgetown University Hospital with refractory hemodynamically compromising incessant atrioventricular tachycardia. A single left-sided accessory pathway was identified and successfully modified acutely. Endocardial delivery of direct current energy provided an extremely effective therapeutic intervention resulting in termination of atrioventricular tachycardia and restoration of stable hemodynamic status. Although a second ablation procedure was necessary to permanently interrupt accessory pathway conduction, the patient has remained free of symptoms without medications for 13 months. 相似文献
122.
Factor V Quebec revisited 总被引:2,自引:5,他引:2
Factor V Quebec has been described as a bleeding disorder that exhibits an autosomal dominant inheritance pattern and presents severe bleeding after trauma. Two members of a fourth-generation (IV.13 and IV.15) Canadian family have been studied in detail and are the subject of this report. Their clinical presentations and histories have been described previously (Tracy et al: J Clin Invest 74:1221, 1984). Persistent abnormalities include mild thrombocytopenia and defective platelet factor V. Plasma factor V is present at near normal concentration and is fully functional. Thus, the bleeding diathesis appears to reflect the absence of platelet factor V activity. The recent report (Hayward et al: Blood 84:110a, 1994 [suppl, abstr]) of multimerin deficiency in these individuals led us to reevaluate these patients. Western blot analyses of platelet lysates developed with a variety of monoclonal antibodies show that the alpha-granule proteins, fibrinogen, von Willebrand factor, factor V and osteonectin are decreased in concentration and significantly degraded in the platelets of these patients. Thrombospondin, while not degraded, is substantially decreased. In contrast, platelet factor 4 and beta-thromboglobulin do not appear to be affected. These observations suggest that the alpha- granules are correctly assembled but the contents are subsequently subjected to proteolytic degradation. The results indicate that factor V Quebec disorder is probably associated with a generalized defect that leads to degradation of most proteins of the alpha-granules. 相似文献
123.
Indeterminate colitis: the real story 总被引:3,自引:4,他引:3
Rudolph WG Uthoff SM McAuliffe TL Goode ET Petras RE Galandiuk S 《Diseases of the colon and rectum》2002,45(11):1528-1534
PURPOSE: Up to one in five patients undergoing surgery for ulcerative colitis will have ambiguous histology, with features of both ulcerative colitis and Crohn's disease, and are categorized as having indeterminate colitis. We hypothesized that functional outcomes in indeterminate colitis patients undergoing ileal pouch-anal anastomosis are comparable with those of ulcerative colitis patients undergoing ileal pouch-anal anastomosis. METHODS: Physician-conducted interviews of 120 consecutive ileal pouch-anal anastomosis patients with a preoperative diagnosis of ulcerative colitis were reviewed, with a mean follow-up of 54 months. All colectomy specimens were reviewed by a single pathologist. Any changes in histologic diagnosis from ulcerative colitis to indeterminate colitis or Crohn's disease, frequency of postoperative complications, pouch function, and long-term postoperative medication usage were recorded. RESULTS: Although postoperative fistulas were more common in indeterminate colitis than ulcerative colitis (26 vs. 10 percent; P = 0.02, chi-squared), no indeterminate colitis patient required a permanent ileostomy as compared with six ulcerative colitis patients. Long-term functional results were similar. Overall, two-thirds of patients developed pouchitis. Ulcerative colitis and Crohn's disease patients were more likely to have had >3 episodes of pouchitis (58 and 72 percent) compared with indeterminate colitis patients (29 percent; P = 0.006, chi-squared). A greater number of Crohn's disease patients required maintenance oral antibiotic therapy (64 percent) to achieve satisfactory functional results compared with both indeterminate colitis and ulcerative colitis patients (20 and 28 percent; P = 0.014, chi-squared). CONCLUSIONS: Although ileal pouch-anal anastomosis patients with indeterminate colitis have more postoperative fistulas, long-term function is equal to that of ulcerative colitis patients and better than Crohn's disease patients. Ileal pouch-anal anastomosis should be offered to patients with indeterminate colitis and those with severe colitis in whom clear differentiation between indeterminate colitis and ulcerative colitis cannot be made. 相似文献
124.
Colbert LH Visser M Simonsick EM Tracy RP Newman AB Kritchevsky SB Pahor M Taaffe DR Brach J Rubin S Harris TB 《Journal of the American Geriatrics Society》2004,52(7):1098-1104
OBJECTIVES: To examine the association between physical activity and inflammatory markers, with consideration for body fatness and antioxidant use. DESIGN: Cross-sectional study, using baseline data from the Health, Aging and Body Composition Study. SETTING: Metropolitan areas surrounding Pittsburgh, Pennsylvania, and Memphis, Tennessee. PARTICIPANTS: Black and white, well-functioning men and women (N=3,075), aged 70 to 79. MEASUREMENTS: Interviewer-administered questionnaires of previous-week household, walking, exercise, and occupational/volunteer physical activities. Analysis of covariance was used to examine the association between activity level and serum C-reactive protein (CRP), interleukin-6 (IL-6), and plasma tumor necrosis factor alpha (TNFalpha) with covariate adjustment. Antioxidant supplement use (multivitamin, vitamins E or C, beta carotene) was evaluated as an effect modifier of the association. RESULTS: Higher levels of exercise were associated with lower levels of CRP (P<.01), IL-6 (P<.001), and TNFalpha (P=.02) (e.g., CRP=1.95 mg/L for no exercise and 1.72 for >180 min/wk). Adjustment for body fatness attenuated the associations somewhat. Use of antioxidant supplements modified the CRP (P(interaction)=.01) and IL-6 (P(interaction)=.08) associations such that concentrations were low in those taking supplements (e.g., CRP=1.79-1.84 across exercise levels) and higher in nonsupplement users who did no exercise (2.03) than in those who did the most (1.72). Among nonexercisers, higher levels of other physical activity were related to lower levels of CRP (P<.01) and IL-6 (P=.02) but not TNFalpha (P=.36), even after accounting for body fat. CONCLUSION: Inflammatory markers are lower in older adults with higher levels of exercise and nonexercise activity and in antioxidant supplement users regardless of exercise level. 相似文献
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127.
Irene Geisner Angela Mittmann Elisa Sheng Tracy Herring Melissa Lewis Christine Lee 《Addiction Research & Theory》2015,23(3):238-245
Research has documented normative perceptions of others' alcohol use and how these related to increased rates of drinking and related problems among college students. Recently, research has expanded this concept to specific events (21st birthday drinking and tailgating). No studies to date examine the construct of normative perceptions of alcohol use for spring break (SB). SB is a known time of risk for increased alcohol use, and understanding whether students overestimate SB drinking norms, variables that influence norms perceptions (gender, ethnicity and travel) and whether SB norms relate to one's own drinking can inform future prevention and intervention efforts. We extend the literature by examining SB normative perceptions: (1) whether or not these perceptions are accurate and (2) the relationship to students' own drinking and related consequences. A random sample (N?=?1583) of students were asked about their SB drinking, consequences and norm perceptions. Students' SB drinking in this study was lower than their perception of typical student SB drinking (p?<?0.001), and women's perceptions were higher than men's (p?<?0.001). After adjusting for demographics and typical drinking, SB norms were significantly associated with SB drinking among those taking a trip over SB (p?<?0.001). After controlling for SB drinking, SB drinking norms were unrelated to consequences. Similar misperceptions exist for SB drinking. Prevention and intervention efforts aimed at reducing SB drinking and consequences, particularly for those planning a trip, may incorporate SB specific social norms education. 相似文献
128.
129.
Emy Hiura Aline del Carmen Garcia Lopes Jeanne Saraiva da Paz Maylla Garschagen Gava Mayra Cunha Flecher Manuela Colares Filippe Elias de Freitas Soares Leandro Abreu da Fonseca Tracy Lacerda Jackson Victor de Araújo Fabio Ribeiro Braga 《Parasitology research》2015,114(9):3301-3308
The objective of this study was to evaluate the infectivity of Toxocara canis eggs after interacting with isolated nematophagous fungi of the species Duddingtonia flagrans (AC001) and Pochonia chlamydosporia (VC4), and test the predatory activity of the isolated AC001 on T. canis second stage larvae after 7 days of interaction. In assay A, 5000 embryonated T. canis eggs previously in contact with the AC001 and VC4 isolated for 10 days were inoculated into domestic chickens (Gallus gallus domesticus), and then these animals were necropsied to collect material (digested liver, intestine, muscles and lungs) at 3-, 7-, 14-, and 21-day intervals after inoculation. In assay A, the results demonstrated that the prior interaction of the eggs with isolated AC001 and VC4 decreases the amount of larvae found in the collected organs. Difference (p?<?0.01) was observed in the medium larvae counts recovered from liver, lung, intestine, and muscle of animals in the treated groups when compared to the animals in the control group. At the end of assay A, a percentage reduction of 87.1 % (AC001) and 84.5 % (VC4) respectively was recorded. In the result of assay B, the isolated AC001 showed differences (p?<?0.01) compared to the control group, with a reduction of 53.4 % in the recovery of L2. Through these results, it is justified to mention that prior interaction of embryonated T. canis eggs with the tested fungal isolates were efficient in reducing the development and migration of this parasite, in addition to the first report of proven predatory activity on L2. 相似文献
130.
The 4G/4G polymorphism of the hypofibrinolytic plasminogen activator inhibitor type 1 gene: an independent risk factor for serious pregnancy complications 总被引:11,自引:0,他引:11
Glueck CJ Phillips H Cameron D Wang P Fontaine RN Moore SK Sieve-Smith L Tracy T 《Metabolism: clinical and experimental》2000,49(7):845-852
The specific aim of the current study of 133 women with at least 1 pregnancy and measures of hypofibrinolytic and thrombophilic gene mutations was to determine retrospectively whether the mutations were associated with adverse pregnancy outcomes including prematurity, miscarriage, stillbirth, intrauterine growth retardation (IUGR), eclampsia, and abruptio placentae. Four gene mutations (factor V Leiden, methylenetetrahydrofolate reductase [MTHFR], prothrombin, and 4G/5G polymorphism of the plasminogen activator inhibitor type 1 [PAI-1] gene) were assessed by polymerase chain reaction (PCR). One hundred twenty-two women were genotyped for all 4 genes and divided into gene mutation (n = 68) and non-gene (n = 54) groups. The gene mutation group included those with at least 1 thrombophilic mutation (heterozygous for factor V Leiden, heterozygous for prothrombin, and homozygous for MTHFR), or hypofibrinolysis with homozygosity for the 4G polymorphism of the PAI-1 gene. The non-gene mutation group included those with no mutation for all 4 genes (wild-type normal) or who were wild-type normal for the prothrombin and factor V Leiden mutations and heterozygous for MTHFR and/or 4G/5G for the PAI-1 gene, neither heterozygosity associated with coagulation abnormalities. The 68 women with gene mutations, versus 54 in the non-gene mutation group, has more prematurity (10% v 4%, chi2 = 5.4, P = .021), more IUGR (3% v 0%, P = .035), and more total complications of pregnancy (37% v 21%, chi2 = 11.6, P = .001). The number of pregnancies (P = .0001) and 4G/4G polymorphism of the PAI-1 gene (P = .029) were positively associated with complications of pregnancy by stepwise logistic regression when the age, number of pregnancies, and all 4 gene mutations were the explanatory variables. Heritable hypofibrinolysis, mediated by 4G/4G homozygosity for the PAI-1 gene, is an independent significant, potentially reversible risk factor for pregnancy complications, probably acting through thrombotic induction of placental insufficiency. 相似文献