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41.
Eun Yeon Joo Jee Hyun Kim Woo Suk Tae Sun Jung Han Seunghwan Kim Myoung-Hee Kim Hong Sik Byun Seung Bong Hong 《Journal of neuroimaging》2004,14(4):365-368
A patient with chronic cerebral paragonimiasis began to have new motor seizures of the right face manifested by clonic contractions that occurred several hundred times a day, consistent with simple partial status epilepticus. Ictal electroencephalogram discharges started from the left frontal region and then spread to the left hemisphere with left frontal maximum. But clinical seizures were limited to the right face. The frequent partial seizures were controlled by the intravenous infusion of phenytoin. Brain magnetic resonance imaging showed multiple conglomerated round nodules with encephalomalacia in the left temporal and occipital lobes. Applying the technique of ictal-interictal single-photo emission computed tomography subtraction, the authors were able to localize the focal ictal-hyperperfusion on left precentral cortex adjacent to the lesions that correspond to the anatomical distribution of left face motor area. 相似文献
42.
The effect of environmental temperature on stroke occurrence in a subtropical climate was studied over a 1-year period by documenting the number of strokes (subdivided into cerebral infarct and intracerebral hemorrhage) admitted into a district hospital in Hong Kong at different temperatures. There was no significant correlation between the number of strokes (or its subtypes) per day per temperature category and the environmental minimum or maximum temperature. However, an association was present between the occurrence of cerebral infarcts and maximum temperature on the day of onset in elderly patients aged 70 years and above. Environmental temperature is not a strong risk factor for the occurrence of stroke in a subtropical climate. 相似文献
43.
Enhancement of hepatic hemangiomas with levovist on coded harmonic angiographic ultrasonography. 总被引:5,自引:0,他引:5
Jung Hoon Kim Tae Kyoung Kim Bong Soo Kim Hyo Won Eun Pyo Nyun Kim Moon-Gyu Lee Hyun Kwon Ha 《Journal of ultrasound in medicine》2002,21(2):141-148
OBJECTIVE: To evaluate the pattern of contrast enhancement with Levovist on coded harmonic angiographic ultrasonography of hepatic hemangiomas. METHODS: Twenty hemangiomas were evaluated with coded harmonic angiographic ultrasonography and a microbubble contrast agent. Verification of the diagnosis of a hemangioma was made by means of dynamic computed tomography (n = 8), dynamic magnetic resonance imaging (n = 1), radionuclide scanning (n = 6), or follow-up ultrasonography (n = 5). Ultrasonographic images were obtained before contrast agent administration and with a bolus injection of 2.5 g of a microbubble contrast agent (300 mg/mL Levovist; Schering AG, Berlin, Germany) every 10 to 15 seconds for 5 minutes. The contrast enhancement patterns of the 20 hemangiomas were assessed. RESULTS: The tumor diameters as measured on ultrasonography were 7 to 97 mm (mean, 26.7 mm). Of the 20 hemangiomas, peripheral globular enhancement with progressive centripetal fill-in was shown in 15 (75%), rimlike enhancement with progressive centripetal fill-in was shown in 2 (10%), and homogeneous enhancement was shown in 1 (5%). In the remaining 2 lesions (10%), the enhancement patterns could not be seen, because they were not found on coded harmonic angiographic ultrasonography. CONCLUSIONS: Coded harmonic angiographic ultrasonography with a microbubble contrast agent can depict the typical enhancement pattern in most hepatic hemangiomas. 相似文献
44.
Doxorubicin-conjugated biodegradable polymeric micelles having acid-cleavable linkages. 总被引:13,自引:0,他引:13
Doxorubicin was chemically conjugated to the terminal end of a di-block copolymer composed of poly(L-lactic acid) (PLLA) and methoxy-poly(ethylene glycol) (mPEG) via two acid-cleavable linkages. A hydrazone bond and a cis-acotinyl bond were formed between doxorubicin and the terminal group of PLLA segment in the block copolymer. Doxorubicin-conjugated PLLA-mPEG di-block copolymers self-assembled to form micelles in aqueous solution. The doxorubicin-conjugated micelles were about 89.1 nm in diameter and their critical micelle concentration was 1.3 microg/ml. These values were comparable with those of unconjugated micelles. In an acidic condition, the conjugated doxorubicin in the hydrazone linkage was readily cleaved, releasing doxorubicin in an intact structure. Doxorubicin-conjugated PLLA-mPEG micelles were more potent in cell cytotoxicity than free doxorubicin, suggesting that they were more easily taken up within cells with concomitant rapid release of cleaved doxorubicin into the cytoplasm from acidic endosomes. 相似文献
45.
Masataka Sakane Ross J. Fox Savio L-Y. Woo Glen A. Livesay Guoan Li Freddie H. Fu 《Journal of orthopaedic research》1997,15(2):285-293
The anterior cruciate ligament has a complex fiber anatomy and is not considered to be a uniform structure. Current anterior cruciate ligament reconstructions succeed in stabilizing the knee, but they neither fully restore normal knee kinematics nor reproduce normal ligament, function. To improve the outcome of the reconstruction, it may be necessary to reproduce the complex function of the intact anterior cruciate ligament in the replacement graft. We examined the in situ forces in nine human anterior cruciate ligaments as well as the force distribution between the anteromedial and posterolateral bundles of the ligament in response to applied anterioi tibial loads ranging from 22 to 110 N at knee flexion angles of 0–90°. The analysis was performed using a robotic manipulator in conjunction with a universal force-moment sensor. The in situ forces were determined with no device attached to the ligament, while the knee was permitted to move freely in response to the applied loads. We found that the in situ forces in the anterior cruciate ligament ranged from 12.8 ± 7.3 N under 22 N of anterior tibial load applied at 90° of knee flexion to 110.6 ± 14.8 N under 110 N of applied load at 15° of flexion. The magnitude of the in situ force in the posterolateral bundle was larger than that in the anteromedial bundle at knee flexion angles between 0 and 45°, reaching a maximum of 75.2 ± 18.3 N at 15° of knee flexion under an anterior tibial load of 110 N. The magnitude of the in situ force in the posterolateral bundle was significantly affected by knee flexion angle and anterior tibial load in a fashion remarkably similar to that seen in the anterior cruciate ligament. The magnitude of the in situ force in the anteromedial bundle, in contrast, remained relatively constant, not changing with flexion angle. Significant differences in the direction of the in situ force between the anteromedial bundle and the posterolateral bundle were found only at flexion angles of 0 and 60° and only under applied anterior tibial loads greater than 66 N. We have demonstrated the nonuniformity of the anterior cruciate ligament under unconstrained anterior tibial loads. Our data further suggest that in order for the anterior cruciate ligament replacement graft to reproduce the in situ forces of the normal anterior cruciate ligament, reconstruction techniques should take into account the role of the posterolateral bundle in addition to that of the anteromedial bundle. 相似文献
46.
In a homogeneous medium of soft tissue the radiation dose distribution due to a nonuniformly distributed beta source can be calculated by convolution of the beta dose point kernel of the nuclide with the source distribution. A possible extension of the technique to the calculation of the dose distribution in heterogeneous media involving relatively simple geometric interfaces requires the knowledge of the resulting perturbation to the beta point kernels in individual media. We simulated a soft-tissue-bone planar interface by a polystyrene (PST)-aluminum junction and measured the change in beta dose from the dose value in homogeneous PST due to a point source of 32P using 7LiF thermoluminescent dosimeters. With the point source at the interface, the dose rates at 0-31, 125-156, and 283-314 mg/cm2 separations from the interface were increased by (12 +/- 3)%, (8 +/- 2)%, and (3 +/- 2)%, respectively, compared with homogeneous PST. With the point source at a PST-air planar interface to simulate a soft-tissue-air junction, the dose rates at 0-31, 139-170, and 283-314 mg/cm2 from the interface were decreased by (25 +/- 4)%, (11 +/- 7)%, and (5 +/- 2)%, respectively. The changes in dose rates for these two interfaces have also been measured with degraded spectra of 32P. Comparison of the experimental data with Monte Carlo calculation for a point source and the two-group method of calculation for a plane source is also presented. 相似文献
47.
Byung Hoon Han Myung Hwan Park Yong Nam Han Lin Keun Woo 《Archives of pharmacal research》1986,9(1):21-23
Over twelve alkaloids were delected in the roots ofPanax ginseng C.A. Meyer. Among them three alkaloids were isolated and were identified as N9-formylharman, ethyl β-carboline-1-carboxylate and perlolyrine on the basis of spectroscopic studies. 相似文献
48.
Yun Jeong Lim Young-Ho Kim Geung Hwan Ahn Ho Kwung Chun Woo Young Jang Jun Haeng Lee Hee Jung Son Poong-Lyul Rhee Jae J Kim Seung Woon Paik Byung Chul Yoo Jong Chul Rhee 《Taehan Sohwagi Hakhoe chi》2004,44(6):314-320
BACKGROUND/AIMS: Carcinogenesis is characterized by the abnormal regulation of cell cycle. The abnormal expression of the regulators of cell cycle may be related to the prognosis. Since the clinical significance of the expression of the three proteins in colorectal carcinomas is still controversial, we evaluated the prognostic value of the expression of cyclin E, p27 and mutant p53 in stage II colorectal cancer. METHODS: The expression levels of cyclin E, p27 and mutant p53 proteins in 41 patients with stage II colorectal carcinomas were analyzed by immunohistochemistry. RESULTS: In the univariate analysis, the level of CEA at diagnosis was associated with disease relapse. In the multivariate analysis, the clinicopathological variables such as age, gender, site of primary tumor, tumor size, state of tumor differentiation and preoperative plasma CEA level were not associated with disease relapse. When Kaplan-Meier survival curves were constructed to determine the prognosis, cyclin E, p27 and mutant p53 expressions did not predict poor prognosis. CONCLUSIONS: Our results suggested that the expression of cyclin E, p27 and mutant p53 proteins did not predict the clinical outcome in the stage II colorectal carcinomas. 相似文献
49.
Eighty-nine consecutive Chinese patients (69 males, 20 females) with acute myocardial infarction treated by 100 mg recombinant tissue-plasminogen activator (rt-PA) (7 intracoronarily, 82 intravenously) at 3.7 +/- 1.0 hours after onset, and intravenous heparin or dipyridamole therapy started at 3 hours, were studied prospectively. Their mean age was 59.6 +/- 10.6 years. Forty-six patients (51.7%) had anterior and 39 patients (43.8%) had inferior infarcts. Clinical evidence of reperfusion was seen in 63 patients (72.8%), while new complications included hypotension (5.6%), heart failure (6.7%), cardiac arrhythmias (76.4%), hematoma around vascular access sites (23.6%), melena (2.2%) and cerebral infarction (2.2%). Maximal changes in coagulation profiles were seen at 3 hours, including a decrease in fibrinogen (by 64.2%), an increase in FDP by 11.7 times and D-dimers by 4.4 times. Nine patients (10.1%) had recurrence of angina and 6 patients (6.9%) died due to pump failure (5) and reinfarction (1). Angiogram at 14 days confirmed TIMI (2 or 3) patency of infarct related arteries in 62/81 (76.5%) patients, with a mean global ejection fraction of 52.5 +/- 12.4%. Nearly all survivors could maintain class I-II functional status after discharge. The safety and promises of rt-PA for acute myocardial infarction in the Chinese were confirmed.
相似文献
50.
Excursion of the flexor digitorum profundus tendon: a kinematic study of the human and canine digits
S Horibe S L Woo J J Spiegelman J P Marcin R H Gelberman 《Journal of orthopaedic research》1990,8(2):167-174
The most common problem following primary flexor tendon repair is the failure of the tendon apparatus to glide, secondary to the formation of adhesions. Early motion following tendon repair has been shown to be effective in reducing adhesions between the tendon and the surrounding sheath. Therefore, it is important to determine the amount of flexor tendon excursion along the digit during joint motion. In this study, the excursion between the flexor digitorum profundus (FDP) tendon and the sheath was examined in both human and canine digits. Based on roentgenographic measurements and joint kinematic analysis, the motion of the bones, the FDP tendon, and the sheath were measured with respect to joint rotations. It was found that the canine flexor tendon apparatus behaved similarly to that of the human for the motions studied. The amount of tendon excursion was very small in regions distal to the joint in motion (approximately 0.1 mm/10 degrees of joint rotation). There was little displacement of the sheath (0.2-0.3 mm), except at the metacarpal joint region during metacarpophalangeal (MCP) joint motion and at the proximal interphalangeal (PIP) joint region during PIP joint motion. Tendon excursion relative to the tendon sheath was the largest in zone II during PIP joint rotation (1.7 mm/10 degrees of joint rotation). These results suggest that PIP joint motion may be most effective in reducing adhesions following tendon repair in zone II. 相似文献