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991.
992.
We describe a case of out-of-hospital cardiac arrest due to ventricular fibrillation in a patient with transient left ventricular apical ballooning syndrome. Our report confirms that left ventricular apical ballooning may have the same complications of myocardial infarction, adding the early ventricular fibrillation to the previous findings of left ventricular wall rupture, ventricular arrhythmias during hospitalization and complete atrio-ventricular block. Moreover, left ventricular apical ballooning may have different and unusual clinical onsets, including sudden cardiac death due to ventricular tachyarrhythmias in the absence of associated symptoms. Therefore, in our opinion left ventricular apical ballooning may be considered as a possible cause of sudden death in otherwise healthy women.  相似文献   
993.
OBJECTIVES: To evaluate how angiotensin-converting enzyme (ACE) gene polymorphism is associated with perioperative blood loss in hip arthroplasty in a geriatric population. DESIGN: A case-control study of subjects consecutively undergoing total hip arthroplasty. SETTING: A department of orthopedic surgery in Italy. PARTICIPANTS: One hundred five patients, mean age +/- standard deviation 68.6 +/- 10.4, undergoing total hip arthroplasty. MEASUREMENTS: ACE gene polymorphism was analyzed using polymerase chain reaction. Decrement of hemoglobin (Hb) and hematocrit (Ht) was calculated as the difference between the preoperative and the lowest postoperative value, measured 1, 2, and 3 days after surgery. Total blood loss was calculated as the sum of intra- and postoperative blood loss. RESULTS: Patients carrying the deletion homozygous and insertion/deletion heterozygous genotypes of the ACE gene show a higher decrement of Hb (P <.01) and Ht (P <.01) and higher total blood loss (P <.007) after hip surgery than subjects carrying the insertion (II) homozygous. The role of ACE gene polymorphism seems hypertension independent. Logistic regression analysis showed that II genotype reduces total blood loss. CONCLUSIONS: This is the largest study evaluating the distribution of ACE gene genotypes in patients undergoing hip arthroplasty and the first investigating the association between bleeding and ACE gene polymorphism. Our data suggest that II genotype is associated with lower total blood loss.  相似文献   
994.
995.
Summary The purpose of this study was to assess the acute effect of an intravenous bolus of the calcium antagonist gallopamil on left ventricular diastolic function using Doppler echocardiography. Fifteen patients with acute myocardial infarction in the first Killip class and sinus rhythm were randomized to an intravenous bolus of gallopamil (50 g/kg over 5 minutes) or placebo in a crossover sequence. Doppler echocardiography was performed at baseline and 15 minutes after each bolus. No patients had received calcium antagonists or beta blockers before the study; all patients received nitroglycerin, which was withdrawn at least 2 hours before the baseline Doppler echocardiogram. The following Doppler parameters were calculated: the early (E) and late (A) peak filling velocities, the velocities ratio (E/A), the diastolic filling time-velocity integral (TVI), the peak filling rate normalized to the mitral stroke volume (nMPFR), the isovolumic relaxation time (IVRT), and the systolic flow velocity integral (SFVI). Expressing the parameters measured after a gallopamil bolus as the percent change of those measured after placebo, E, E/A, and nMPFR increased by 25.5±11.5%, 30.6±15.5%, and 19.0±12.2%, respectively (p<0.001); IVRT decreased by 13.5±7.0% (p<0.001); and TVI increased mildly by 6.9±9.9% (p=0.01). SFVI and A did not change significantly. Negligible differences were observed between placebo and baseline values. Heart rate, mean blood pressure, and left ventricular and atrial diameters did not change significantly. It was concluded that gallopamil infusion improves early left ventricular filling and relaxation in patients with acute myocardial infarction. Considering the unchanged loading conditions, this indicates an improvement in left ventricular diastolic performance.  相似文献   
996.
We present a novel approach to optical mammography and initial clinical results. We have designed and developed a frequency-domain (110-MHz) optical scanner that performs a transillumination raster scan of the female breast in approximately 3 min. The probing light is a dual-wavelength (690 and 810 nm, 10-mW average power), 2-mm-diameter laser beam, and the detection optical fiber is 5 mm in diameter. The ac amplitude and phase data are processed with use of an algorithm that performs edge effect corrections, thereby enhancing image contrast. This contrast enhancement results in a greater tumor detectability compared with simple light intensity images. The optical mammograms are displayed on a computer screen in real time. We present x-ray and optical mammograms from two patients with breast tumors. Our initial clinical results show that the frequency-domain scanner, even at the present stage of development, has the potential to be a useful tool in mammography.  相似文献   
997.
Particular attention has been recently dedicated to the development of a sarcoidosis-like form in patients with common variable immunodeficiency (CVI). In sarcoidosis a 5-fold increase in the number of cells in the bronchoalveolar lavage compared with normal controls has been described and the predominance of CD4+ T cells is a common feature. In contrast to patients affected by sarcoidosis or CVI, patients with co-existence of the two diseases had a more favorable prognosis, as progressive pulmonary fibrosis occurred only in a few cases even when persistent alveolar lymphocytosis was present. Moreover, patients presenting with concomitant sarcoidosis and CVI, showed a lower rate of respiratory infections and of the evolution towards bronchiectasies in comparison with patients affected by CVI alone. The clinical evolution observed in our patients was similar with that reported in other studies and confirms their clinical features. One may speculate that the increase in the number of macrophages and T lymphocytes, as suggested by the increased cellularity in the bronchoalveolar lavage of these patients, can produce a peculiar microenvironment characterized by high levels of soluble factors (cytokines). In turn, the latter could be responsible for a more efficacious effector phase of the immune response. This may explain the reduced rate of infectious diseases and consequently of bronchiectasies observed in CVI patients.  相似文献   
998.
Factors influencing the progression of liver disease and the development of hepatocellular carcinoma (HCC) in chronic hepatitis C virus (HCV) infection are poorly understood. Inherited variations of drug-metabolizing enzyme (DME) activities may affect liver damage and cancer risk by modifying individual susceptibility to endogenous or exogenous toxic compounds. We investigated the association of liver disease severity with common alleles of microsomal epoxide hydrolase (mEH), an enzyme involved in the metabolism of highly reactive epoxide intermediates. Three polymorphisms (Tyr113His, His139Arg, and -613C/T) were analyzed by polymerase chain reaction (PCR) restriction fragment length polymorphisms (RFLPs) in 394 patients at different stages of disease, including 92 asymptomatic carriers, 109 patients with chronic hepatitis, 100 patients with cirrhosis, and 93 patients with HCC. Reference allele frequencies were obtained from 99 healthy blood donors. Allele distributions between categories were compared using the chi(2) test; odds ratios (ORs) and 95% CI were calculated to express relative risks. Allele frequencies among 99 healthy controls were as follows: 15.1% for 113His/His, 4.0% for 139Arg/Arg, and 46.5% for -613C/T. mEH 113His/His homozygotes were overrepresented in advanced stages of disease, in particular among HCC patients (27.9%; P =.03; OR, 2.2; 95% CI, 1.0-4.6). Differences were more pronounced among men and between extreme patient categories. When mEH genotypes were combined to express a metabolic phenotype, very slow metabolizers were highly prevalent among cirrhotic and HCC patients (18% vs. 3.3% in carriers; P <.001). In conclusion, mEH gene polymorphisms were significantly associated with HCV-related liver disease severity and HCC risk. Men were at higher risk than women; this might be explained by hormonal regulation of gene expression or by differential exposure to environmental toxins.  相似文献   
999.
The surgical treatment of short-bowel syndrome has been traditionally based on the correction of mechanical obstruction, which is responsible for bacterial overgrowth syndrome, or on intestinal expansion procedures.Since the introduction of clinical intestinal transplantation by Lillehei in 1964, there have been remarkable advances in the immunosuppressive regimens to control rejection and in preservation techniques, monitoring and critical care. Newer and more powerful immunosuppressants have helped to transform intestinal transplantation into a clinical reality—transplantation can now be a life-saving procedure for patients with intestinal failure. It is currently indicated in the event of life-threatening complications of an underlying disease or from total parenteral nutrition (TPN). Rehabilitation in successful cases is excellent.  相似文献   
1000.
OBJECTIVES: This study sought to assess the relationship between duration of ischemia and both myocardial transmural necrosis (TN) and severe microvascular obstruction (SMO), by contrast-enhanced magnetic resonance (CE-MR), in patients with acute myocardial infarction (AMI) treated with angioplasty (PCI), and to estimate the risk of TN and SMO with the duration of ischemia. BACKGROUND: The impact of ischemic time on myocardial and microvascular injury is not well characterized in people. METHODS: We performed CE-MR in 77 patients with first AMI, 5 +/- 3 days after successful PCI. The AMI was labeled as transmural if hyperenhancement at CE-MR was extended to > or =75% of the thickness in two or more ventricular segments. The SMO was identified as areas of late hypoenhancement surrounded by hyperenhanced tissue. The relationship between ischemic time and CE-MR evidence of SMO or TN was evaluated by logistic regression. RESULTS: Thirteen patients were excluded because of preprocedural Thrombolysis In Myocardial Infarction (TIMI) flow grade 3 of the infarct-related artery. For the remaining 64 patients, the mean time to treatment was 190 +/- 110 min, 45 (65%) patients had TN and 23 (39%) had SMO. Mean pain to balloon time was 90 +/- 40 min, 110 +/- 107 min, and 137 +/- 97 min in patients without TN and SMO, with TN but without SMO, or with both TN and SMO, respectively (p = 0.001). Multivariate analysis showed that time delay was significantly associated both with TN (odds ratio per 30 min, 1.37, p = 0.032), and SMO (odds ratio per 30 min, 1.21; p = 0.021). CONCLUSIONS: In AMI patients with impaired coronary perfusion undergoing PCI, the risk of TN and SMO increases with the duration of the ischemic time.  相似文献   
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