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591.
BACKGROUND: Femoral pseudoaneurysm (FPA) is one of the common complications of percutaneous catheterization procedures performed via the femoral artery. The aim of this research was to evaluate factors associated with FPA of sufficient clinical significance that they required surgical treatment after diagnostic or interventional cardiac catheterization. METHODS: We evaluated 41,322 transfemoral catheterization procedures performed in our center within 7 years. Among all procedures, 630 FPAs developed that required surgical repair. Eighty-five cases were managed by compression with duplex guidance. As a case-control group, 1260 patients were selected from the patients who had been catheterized during the same time period but did not develop FPA. Two controls were selected for each study patient, matched according to age, sex, and catheterization day. Body mass index, hypertension, diabetes mellitus, catheter diameter, coronary artery disease, atherosclerosis, and number of cases performed per day in a particular room were evaluated as risk factors by using multivariate techniques. RESULTS: Femoral pseudoaneurysm required operative repair in 1.1% (n = 398) of patients who underwent cardiac catheterization for diagnostic purposes and in 4.7% (n = 232) of patients after cardiac interventional procedures. Factors found to be independently predictive of FPA were hypertension (P = .011; odds ratio, 1.52), diabetes mellitus (P = .035; odds ratio, 1.11), coronary artery disease (P = .022; odds ratio, 1.21), larger (> or = 28 kg/m2) body mass index (P < .001; odds ratio, 2.21), larger number of cases (> or = 18) performed per day in a particular room (P < .001; odds ratio, 2.39), and larger (> or = 7F) catheter diameter (P < .001; odds ratio, 2.82). CONCLUSIONS: Due to the development of technology and experience, more and more diagnostic and interventional catheterization procedures are performed on a daily basis. In our study, a high volume of cases in a particular room and use of large catheters were important risk factors for FPA complications. When these situations are combined with other risk factors (such as obesity, diabetes mellitus, hypertension, and arteriosclerosis), giving particular attention to local compression therapy would be more crucial to decrease the FPA rate.  相似文献   
592.
OBJECTIVE: The aim of this study was to assess the effect of aortic coarctation surgery in adult patients on arterial blood pressure in the early postoperative period. METHODS: Ninety-three adult patients (61 male, 32 female) aged 15-43 years who had operation since 1962 for aortic coarctation in Siyami Ersek Cardiovascular Surgery Center were retrospectively evaluated. Tube graft interposition was done in 31 patients; resection and end-to-end anastomosis were performed in 32 patients; 24 patients had undergone pathchplasty; and 6 patients by-pass shunting performed. The effect of surgery on the blood pressure was investigated. RESULTS: The mean systolic and diastolic blood pressure significantly reduced after operation (systolic 193.6 +/- 33.7 mmHg vs 147.4 +/- 22.0 mmHg, diastolic 99.8 +/- 17.9 mmHg vs 82.0 +/- 10.8 mmHg). From 93 patients (all with hypertension) 54 (58%) became normotensive after operation according to VIth Joint National Committee classification. The number of normotensive patients after operation was 28 (of 37) for 15-19 years age group, 14 (of 23) for the 20-24 years age group, 4 (of 16) for 25-29 years age group, 6 (of 11) for 30-34 years age group, and 2 (of 6) for the over 35 years old age group. CONCLUSION: The diastolic and systolic blood pressures reduce significantly in the adult patients operated for aortic coarctation. On the other hand, persistent hypertension seemed to increase in the older age groups in spite of the surgery.  相似文献   
593.
Mert T  Gunay I  Daglioglu YK 《Pharmacology》2004,72(3):157-166
After a peripheral nerve injury, ion channel organization and the electrical properties of nerve fibers drastically change during the regeneration process. The present study was designed to compare the frequency-dependent characteristics of regenerating nerves in the presence of 4-aminopyridine (4-AP) and tetraethylammonium (TEA). The results showed that increasing the stimulus frequency produced a greater impulse blockade (frequency-dependent block--FDB) and distinct hyperpolarizing afterpotentials (HAPs) in regenerating nerves. In particular, regenerating sciatic nerves 15 days post-crush (dpc) were more sensitive to the frequency-dependent stimulations than 38-dpc and intact nerves in the presence or absence of drugs. The frequency-dependent effects of TEA on the compound action potentials (CAPs) appeared when TEA was applied to 4-AP-treated nerves. This shows that TEA-sensitive channels may not be masked by the myelin. 4-AP was here found to have more pronounced frequency-dependent effects on regenerating nerves than on intact nerves. Delayed depolarization (in 38-dpc: 22.6 +/- 1.3 mV and 47.52 +/- 3.63 ms, in intact: 12.0 +/- 1.9 mV and 88.51 +/- 4.72 ms) elicited by 4-AP resulted in an increase in FDBs and HAP amplitudes. These results suggest that 4-AP-sensitive channels may play important roles in frequency-dependent nerve conduction. Consequently, regenerating or myelin damaged nerves are more sensitive to repetitive firing with or without drug. An understanding of the frequency-dependent properties of regenerating nerves may be of value in the treatment of the nerve diseases.  相似文献   
594.
BACKGROUND: Lower ministernotomy has become a more popular approach for many heart operations. However, cannulation of the ascending aorta may cause serious complications. Femoral and brachial arteries have been used for alternative arterial cannulation sites. MATERIALS AND METHODS: The lower ministernotomy approach was used in 65 patients. Ascending aortic cannulation was performed in group 1 (n = 38), femoral cannulation in group 2 (n = 12), and brachial cannulation in group 3 (n = 15) patients. Brachial artery diameter was measured preoperatively by Doppler ultrasound in the preoperative period. RESULTS: Average cross-clamp time for femoral and brachial artery cannulated patients was significantly shorter than in patients in group 1 (31 +/- 9 and 35 +/- 6 minutes, respectively) (p = 0.034). Total cardiopulmonary bypass (CPB) time was 56 +/- 11 minutes for group 1, 39 +/- 7 minutes for group 2, and 41 +/- 5.4 minutes for group 3 (p = 0.041). Operation time was 112 +/- 24, 88 +/- 12, and 91 +/- 11 minutes for the groups 1, 2, and 3, respectively. There was also statistically significant difference between group 1 and group 3 comparisons with regard to CPB time (p = 0.041). Difficult exposure from many cannulas impedes access and lengthens the operation in group I. Superficial wound infection developed in seven patients in group 1, one patient in group 2, and one patient in group 3. CONCLUSION: Cannulation of the brachial artery is superior to the femoral due to possible infection and lymph leakage with the latter and both are superior to central cannulation when lower ministernotomy is performed. By avoiding the difficulties of central aortic cannula placement the operative time is decreased and possible wound edge is protected as lesser exposure is required.  相似文献   
595.
BACKGROUND: Slime is one of the important structures of certain bacterial strains involved in nonspecific adherence. This study was conducted to determine the role of neuraminidase on slime formation and adherence of slime-forming coagulase-negative staphylococci to inert surface. METHODS: Quantitative biofilm and qualitative bacterial adherence assays were performed with increasing concentrations of neuraminidase extracted from Clostridium perfringens-treated bacteria in polystyrene plates and polypropylene tubes. RESULTS: Slime production of slime-forming, coagulase-negative staphylococci was significantly decreased dose dependently at > or =100 mU/mL (p <0.001). Bacterial adherence to smooth surface was impeded at > or =100 mU/mL of neuraminidase treatment and adherence results were comparable with slime production assay results. CONCLUSIONS: Sialic acid may be a constituent molecule of slime and involved in bacterial adherence to inert surface. These results represent new insight into the mechanism of slime production and adherence of slime-forming, coagulase-negative staphylococci to inert surface.  相似文献   
596.
597.
AIM: The aim was to rapidly assess existing breastfeeding patterns, beliefs and attitudes in the province of Diyarbakir, a socio-economically disadvantaged region of Turkey. METHODS: A cross-sectional survey exploring demographic and breastfeeding patterns was carried out among 921 mothers with children 6-18 mo of age. Results were quantitatively analysed. Focus group interviews dealing with beliefs and attitudes were separately carried out among 107 mothers and analysed by qualitative content analysis. RESULTS: Nearly all mothers had breastfed their infants at some time, but exclusive breastfeeding was rare. About 62.2% of the mothers had waited for at least 24 h before initiating breastfeeding. Almost half of the infants received sweetened water as a first feeding. There was agreement on the superiority of breastfeeding and awareness of its contraceptive effect. Early introduction of sugared water, water and supplementary feeds was considered desirable. Working in the fields and pregnancy were considered situations counteracting breastfeeding. CONCLUSION: The attitude to breastfeeding was highly positive, but more information is needed to encourage the use of colostrum, discourage early supplementation and promote exclusive breastfeeding during the first 6 mo of life.  相似文献   
598.
BACKGROUND: Results from the International Suicide Prevention Trial (InterSePT) indicate that clozapine is more effective than olanzapine in reducing suicidal behavior in schizophrenic and schizoaffective patients. However, because InterSePT allowed the uncontrolled use of concomitant psychotropic medications (CPMs), it is possible that the antisuicidal effect of clozapine may have been influenced by greater use of such agents. This article describes the use patterns of CPMs during InterSePT and examines whether CPM use may have affected study outcome. METHOD: In this study, 479 patients received clozapine and 477 patients received olanzapine. Concomitant psychotropic medications were grouped into 4 classes: antipsychotics, antidepressants, sedatives/anxiolytics, and mood stabilizers. The doses of each CPM were converted into dosage equivalents of standard reference drugs. An analysis of covariance was performed to compare mean daily doses of CPMs between the 2 groups over the 2-year treatment period. The duration of treatment for each patient was 2 years, with the first patient entering the study in March 1998 and the last patient completing treatment in February 2001. RESULTS: Approximately 90% of patients in both treatment groups received at least 1 CPM. The mean +/- SD number of CPMs per patient was 3.8 +/- 2.90 in the clozapine group and 4.2 +/- 3.16 in the olanzapine group. For each CPM class, the mean daily dose was statistically significantly lower in the clozapine group (antipsychotics, p <.001; antidepressants, p <.01; sedatives/anxiolytics, p <.001; mood stabilizers, p <.05). Analyses of CPM use by study intervals, suicide attempters versus nonattempters, study completers versus noncompleters, and geographic region resulted in similar findings. CONCLUSION: The results support the conclusion that the effects of clozapine in reducing the risk of suicidal behavior derive from its intrinsic pharmacology and not from the influence of concomitant psychotropic medications.  相似文献   
599.
Divalent cations, such as calcium and magnesium, are constantly present in extracellular compartment of most organisms. Modification of extracellular concentrations of divalent ions causes changes in physiologic functions, such as excitability and conduction of the nerves. The present study was designed to investigate and compare the effects of calcium and magnesium on nerve conduction and lidocaine-induced nerve conduction block. The aim of our study was to contribute to better understanding of physiological and pharmacological roles of divalent cations. Experiments were conducted on the sciatic nerves by using the sucrose-gap recording technique. We evaluated the effects of test solutions containing different calcium or magnesium concentrations, prepared with or without lidocaine, on compound action potentials to determine physiological and pharmacological roles of these cations. After the control recordings, the nerve was exposed to Ringer's solution containing 0, 1.9, 3.8 mM Ca2+ and 1.9 and 3.8 mM Mg2+ with or without 1 mM lidocaine. Decreasing the Ca2+ concentrations in Ringer's solution with or without lidocaine enhanced both tonic and phasic blocks. However, increased Mg2+ concentration did not change the tonic blocks but increased the phasic blocks. In conclusion, the results suggested but not prove that Ca2+ and Mg2+ may have different mechanisms of action on peripheral nerves. While Ca2+ directly affects the gating of Na+ channels, action of Mg2+ can be explained by surface charge theory.  相似文献   
600.
Primary chylopericardium is a rare entity. Here we describe a 36-year-old, asymptomatic male in whom pericardial effusion was detected by chest X-ray and echocardiography on routine health control. After pericardiocentesis that revealed the chylous nature of the fluid, partial pericardiectomy without duct ligation was carried out. In the follow-up period, there was no evidence of pericardial fluid on chest X-ray and echocardiography, at three months after the procedure.  相似文献   
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