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41.
BACKGROUND: The purpose of this study was to determine the effects of systemic infusions of nitroglycerin and sodium nitroprusside on flow distribution and wall shear stress in the microcirculation. METHODS: With university approval, the cremaster muscle of 28 anesthetized (70 mg/kg pentobarbital given intraperitoneally) hamsters (Harlan Sprague Dawley: Syrian; weight, 121+/-11 g [mean +/- SDD) was observed using in vivo fluorescence microscopy. Arteriolar diameter, erythrocyte flux, and velocity were measured for a feed arteriole and its sequential branches. Observations were made during control (mean arterial pressure, 88+/-4 mm Hg) and after 30 min of intravenous delivery of sodium nitroprusside or nitroglycerin, titrated to decrease mean arterial pressure by 20 mm Hg. RESULTS: Sodium nitroprusside significantly dilated select upstream portions of the network (23+/-2.6 to 29+/-2.6 microm); no arterioles were dilated with nitroglycerin. Erythrocyte flux into the feed (i.e., inflow into the arteriolar network) and into the sequential branches (i.e., distribution within the network) were evaluated. With nitroglycerin, inflow decreased significantly from 1,560+/-335 to 855+/-171 cells/s, and flux into the branches decreased evenly. With sodium nitroprusside, inflow increased significantly to 2,600+/-918 cells/s, yet cells were "stolen" from upstream branches (a decrease from 425+/-67 to 309+/-87 cells/s in the first branch). Excess flow passed into a downstream "thorough-fare channel," significantly increasing flux from 347+/-111 to 761+/-246 cells/s. Wall shear stress decreased uniformly with nitroglycerin infusion, with a decrease in the feed from 8.8+/-2.5 to 6+/-1.7 dyn/cm2. With sodium nitroprusside, variable changes occurred that were location specific within the network. For instance, at the inflow point to the network, wall shear stress changed from 8.3+/-2.5 to 4.2+/-3.3 dyn/cm2. CONCLUSIONS: Nitroglycerin infusion promoted homogeneity of flow. Sodium nitroprusside significantly increased the heterogeneity of flow within this arteriolar network; an anatomic location for steal induced by sodium nitroprusside is identified. 相似文献
42.
Ramazan Karanfil Alper Keten Cem Zeren M. Mustafa Arslan Ali Eren 《Journal of Forensic and Legal Medicine》2013,20(5):404-407
IntroductionSex crimes remain an important problem all over the world. Very few studies about sexual offenses in Turkey have been published. Sexual assault is a serious social problem that constitutes serious health conditions affecting the lives of involved individuals.In this study, we aimed to investigate socio-demographic features of victims, assailant–victim relationships and sexual assault findings.Material and methodsA total of 324 sexual assault victims presenting to and examined in the Department of Forensic Medicine, Kahramanmaras Sutcu Imam University Medical Faculty, between January 2007 and December 2010 were included in the study. The victims completed a survey at face to face interviews.ResultsOf 324 victims, 268 (82.7%) were female and 56 (17.3%) were male. The mean age of the victims was 16.78 ± 7.16 years. In all cases, types of the assaults were as following; vaginal penetration in 160 (49.4%), anal penetration in 117 (36.1%), oral penetration with penis in 7 (2.2%) and in the form of kissing, fondling, touching the sex organ and rubbing the sex organ in 60 (18.5%) cases. Of all the assaults, 149 (46%) were found to take place in the assailants' homes and 49 (15.1%) in the victims' homes. Of 139 cases, 85 (26.3%) had genital injury alone and 54 (16.7%) had anal injury.ConclusionOn the contrary to the previous studies, this study revealed that sexual assaults occurred mostly in the assailants' homes and that the incidence of anal trauma was higher. 相似文献
43.
Aluminium (Al) is the third most prevalent element, representing approximately 8% of total mineral components in the earth's crust (1). Chronic exposure to Al is mainly encountered at particular work places, for example, in foundries or in the Al powder industry, as an occupational exposure. In case of occupational Al exposure, inhalation is the main route of uptake. Chronic exposure to Al is associated with skeletal, neurological, hematological and lung changes. Studies regarding the Al powder industry showed that long-term inhalative exposure to Al can induce pulmonary fibrosis (2). Although there is only one report about ventricular tachycardia as a cardiac manifestation in occupationally exposed persons (3), in this report, we presented a case that had Mobitz type I second-degree atrioventricular block and nonsustained ventricular tachycardia. To our knowledge, this is the first report in chronic poisoning. 相似文献
44.
Yavuz Demiraran Mustafa Albayrak Ilknur Suidiye Yorulmaz Ismail Ozdemir 《Journal of anesthesia》2013,27(2):175-179
Purpose
The aim of the present study was to investigate whether levobupivacaine and tramadol wound infiltration decreases postoperative pain following Cesarean section and reduces the need for analgesics in the immediate post-delivery period.Methods
Ninety patients (aged 18–40 years) scheduled for elective Cesarean section under general anesthesia were randomly allocated to one of the three groups: the placebo group (group P) received 20 mL local wound infiltration with 0.9 % saline solution; the levobupivacaine group (group L) received 20 mL local wound infiltration with levobupivacaine 0.25 %; and the tramadol group (group T) received 20 mL local wound infiltration with 1.5 mg/kg tramadol within 0.9 % saline solution. Following the closure of the uterine incision and the rectus fascia, 20 mL solution was infiltrated subcutaneously along the skin wound edges. The primary outcome was 24-h tramadol consumption. Secondary outcomes were recorded VAS scores, diclofenac requirement, fever, vomiting, and wound infection.Results
At 15 min postoperatively, VAS values were lower in groups T and L than group P (P = 0.0001). The mean 24-h tramadol consumption was lowest in group T (P = 0.0001) and it was lower in the group L compared to group P (P = 0.007) (401.6, 483.3, and 557.5 mg for T, L, and P groups, respectively). There was no difference among groups regarding the need for supplemental analgesia (rescue diclofenac doses) (P > 0.05).Conclusions
We conclude that wound infiltration with tramadol and levobupivacaine in patients having Cesarean section under general anesthesia may be a good choice for postoperative analgesia. 相似文献45.
Ahmet Aydin Alpay Özenci Haluk Özcanli Hakan Özdemir Mustafa Ürgüden 《Knee surgery, sports traumatology, arthroscopy》2002,10(6):343-346
The purpose of this study was to identify a reliable reference point for measuring anterior intermeniscal ligament thickness and to investigate the morphological characteristics of the ligament at its attachment site to anterior horns of both menisci by MRI. MRI was performed in 98 knees of randomly chosen patients. The anterior intermeniscal ligament was detected in 61 knees (62.2%). The average ligament length was 29.8 mm. Men had significantly longer anterior intermeniscal ligament than women patients (32.5 vs. 27.8 mm). The thickness of anterior intermeniscal ligaments at their attachment sites to menisci was usually less than 3 mm; a thickness of 3 mm or more at the attachment site to anterior horns of the meniscus was defined as "cordlike." It is suggested that the "cordlike" pattern is a variation of the anterior intermeniscal ligament's attachment characteristics, and that this might have a significant role in meniscal translations during knee motion, and also that the "cordlike" pattern could be clinically important with respect to its relationship to the anterior horn of medial meniscus. The attachment site of the ligament is a reliable reference point for measuring its thickness. 相似文献
46.
Comparison of low-dose and standard-dose helical CT in the evaluation of pulmonary nodules 总被引:10,自引:0,他引:10
The purpose of this study was to investigate the diagnostic accuracy of low-dose helical computed tomography by comparing
the number of nodules detected at low- and standard-dose CT. The prospective study included 25 patients who were referred
to CT scan for the assessment of pulmonary metastases. All patients underwent CT examinations at both standard- (200 mA, 120 kV,
collimation 5 mm, table feed 10 mm per rotation) and low-dose (50 mA, 120 kV, collimation 5 mm, table feed 10 mm per rotation).
The number of nodules detected at each protocol was recorded. The size of the nodules was measured electronically and categorized
as <3, 3–4.9, 5–6.9, 7–9.9, and ≥10 mm. Finally, the nodules detected at only standard- or low-dose CT were assessed for the
underlying causes of discrepancy. In 25 patients, 533 nodules were detected at standard-dose, whereas 518 nodules were observed
at low-dose CT. There were no statistically significant differences in the number of nodules detected at standard- or low-dose
CT (p>0.05). Four hundred ninety-one (87.7%) nodules were detected at both standard- or low-dose CT, 42 (7.5%) nodules were observed
only at standard-dose CT, and 27 (4.8%) nodules were seen only at low-dose CT. The sensitivity of low-dose CT was 92.5% for
all nodules, 88.1% for nodules <5 mm, and 97.4% for nodules ≥5 mm. No significant image artifact interfering with nodule detection
was observed at low-dose CT. The low-dose CT protocol used in this study provided images of adequate quality; thus, it can
be used reliably in the detection or exclusion of pulmonary nodules.
Electronic Publication 相似文献
47.
Computed tomography features in malignant pleural mesothelioma and other commonly seen pleural diseases. 总被引:4,自引:0,他引:4
Muzaffer Metintas Irfan Ucgun Osman Elbek Sinan Erginel Selma Metintas Mustafa Kolsuz Emel Harmanci Fusun Alatas Gunnar Hillerdal Ragip Ozkan Tamer Kaya 《European journal of radiology》2002,41(1):1-9
OBJECTIVE: To investigate the computed tomography (CT) features of malignant pleural mesothelioma (MPM) cases, comparing them to those in other malignant and benign pleural diseases. MATERIALS AND METHODS: We reviewed the CT findings of 215 patients; 99 with MPM, 39 with metastatic pleural disease (MPD), and 77 with benign pleural disease. The findings were evaluated in univariate and multivariate analysis for differentiation of pleural diseases. RESULTS: In patients with MPM, the most common CT features were circumferential lung encasement by multiple nodules (28%); pleural thickening with irregular pleuropulmonary margins (26%); and pleural thickening with superimposed nodules (20%). In the majority (70%) of cases, there was rind-like extension of tumor on the pleural surfaces. In multivariate analysis, the CT findings of "rind-like pleural involvement", "mediastinal pleural involvement", and "pleural thickness more than 1 cm" were independent findings in differentiating MPM from MPD with the sensitivity/specificity values of 70/85, 85/67, and 59/82, respectively. "Rind-like pleural involvement", "mediastinal pleural involvement", "pleural nodularity" and "pleural thickness more than 1 cm" were independent findings for differentiation of malignant pleural diseases (MPM+MPD) from benign pleural disease with the sensitivity/specificity values of 54/95, 70/83, 38/96, and 47/64, respectively. Invasion of thoracic structures such as pericardium, chest wall, diaphragm, mediastinum, with pleural disease and nodular involvement of fissures, was detected infrequently; however, since these invasions were not seen in benign pleural diseases, it was concluded these invasions, if detected on a CT scan, directly suggested malignancy. CONCLUSION: A patient has extremely high probability of malignant pleural disease if one or more of these CT findings are found and the possibility of MPM is high. These findings may be important for patients in bad state or patients who do not want any invasive biopsy procedures. It is also possible to identify cases with a low probability of malignant disease. 相似文献
48.
Hepatic adenomatosis: MRI demonstration with the use of superparamagnetic iron oxide 总被引:2,自引:0,他引:2
This case report describes a case of a 38-year-old woman with hepatic adenomatosis. MRI revealed five hyperintense nodular liver lesions on T1-weighted images which were hypo-isointense with the liver parenchyma on T2-weighted images. Serial gadolinium-enhanced images did not reveal distinctive imaging findings. With the use of superparamagnetic iron oxide (SPIO) particles, hyperintense adenomas revealed signal loss on T1-weighted images after SPIO. Two subcapsular adenomas were resected based on MRI findings and histopathology confirmed MRI diagnosis. 相似文献
49.
OBJECTIVE: The aim of this study was to evaluate the diagnostic effectiveness of kinematic magnetic resonance fluoroscopy (KMRF) on patients with patellofemoral incongruency. MATERIALA AND METHODS: 17 patients (20 knees) and 10 healthy volunteers (20 knees), all men (mean age 29.4 years, S.D. 9, range 16-50), were included to our study. Only male subjects were studied because of potential biomechanical differences between sexes. KMRF was used to perform kinematic MR imaging of patellar alignment and tracking in 10 healthy subjects and 17 patients with a provisional clinical diagnosis of abnormal patellofemoral joints. The patellofemoral joints were examined with the knee in different angles of active flexion. At each knee position, real time kinematic and axial MRF image was used to focus on the sagittal plane, followed by an axial image focused through the middle of the patella. Three angles were measured: patellar tilt angle (PTA), sulcus angle (SA) and congruence angle (CA). RESULTS: Five patterns of malalignment were identified and studied. Two patellofemoral joints were normal, 10 had lateralization of the patella, 2 had patellar tilt, 2 had lateralization and patellar tilt (i.e. excessive lateral pressure syndrome) and 4 had medialization of the patella. CONCLUSION: KMRF is an effective method in evaluating patellofemoral incongruency. Short time duration of investigation, ability to get nearly real time images, suitable temporal contrast resolution and investigation from very different angles of knee are important advantages of the method. 相似文献
50.
Erkan Yildirim Erkan Kaptanoglu Kanat Ozisik Ethem Beskonakli Ozerk Okutan Mustafa F Sargon Kamer Kilinc Unal Sakinci 《European journal of cardio-thoracic surgery》2004,25(4):523-529
OBJECTIVE: We aimed to demonstrate the time-dependent ultrastructural changes in pneumocyte type II cells following brain injury, and to propose an electron microscopic scoring model for the damage. METHODS: Forty Wistar-Albino female rats weighing 170-200 g were used. The rats were allocated into five groups. The first group was the control and the second was the craniotomy without trauma. The others were trauma groups. Weight-drop method was used for achieving head trauma. Samples were obtained from the right and left pulmonary lobes at 2-, 8-, and 24-h intervals after transcardiac perfusion. An electron microscopic scoring model was used to reveal the changes. RESULTS: There were no ultrastructural pathological findings pointing to lung injury in any rat of the control groups. There was intense intracellular oedema in type II pneumocyte and interstitial oedema in the adjacent tissue in trauma groups. Oedema in mitochondria and dilatation in both smooth endoplasmic reticulum and Golgi apparatus was more evident in the 8- and 24-h trauma groups. The chromatin dispersion was disintegrated in the nucleus in all trauma groups. Scores of all trauma groups were significantly different from the controls (P<0.05). All trauma groups were different from each other at significant levels (P<0.05 for each trauma groups). CONCLUSIONS: The data suggested that ultrastructural damage is obvious at 2 h and deteriorates with time. The electron microscopic scoring model worked well in depicting the traumatic changes, which were supported by lipid peroxidation. Further experiments are needed to determine the exact outcome after brain death model. 相似文献