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941.
The possible association between the risk of death from sudden infant death syndrome (SIDS) and the levels of magnesium in drinking water from municipal supplies was investigated in a matched case-control study in Taiwan. Characteristics for all SIDS deaths (501 cases) among Taiwan residents from 1988 through 1997 were compared with those of people who died from other causes (501 controls). The levels of magnesium in the drinking water of these residents were determined from data obtained from the Taiwan Water Supply Corporation (TWSC). The controls were pair-matched to the SIDS cases by sex, month and year of birth. The results of our study show that there is a significant trend towards a decreased risk of SIDS with increasing magnesium levels in drinking water.  相似文献   
942.
Cadmium (Cd) stimulates the production of reactive oxygen species (ROS) and causes cell damage. We investigated here the feasibility of using a cell permeable superoxide dismutase/catalase mimetic, EUK-8, to reduce the Cd-induced ROS and cytotoxicity in Chinese hamster ovary cells. EUK-8 reduces the ROS level caused by Cd treatment. EUK-8 also curtails propidium iodide (PI) influx and increases the viability of Cd-treated cells. The efficacy of EUK-8 as a Cd antidote diminishes gradually when added at a later stage of Cd treatment. EUK-8 blocks Cd transport into cells. It is ineffective in accelerating the efflux of metals from the cells. EUK-8 is a Mn-salen complex. Mn decreases the uptake and cytotoxicity of Cd, while salen perturbs the membrane integrity and increases the uptake and cytotoxicity of Cd. Salen is able to bind Cd, and the Cd-salen complex formed does not perturb the integrity of cell membranes and thus the influx of metal is not enhanced. Our results reveal a differential effect of salen and Mn-salen complex on the transport of Cd with subsequent different levels of cell damage.  相似文献   
943.
I S Chiu  C R Hung  J K Wang  F F Wu  S W How 《台湾医志》1990,89(11):997-1003
We studied the surgical anatomy of 14 hearts with isolated ventricular septal defects and the precise relationship of the atrioventricular conduction axis to their rims. Ten of these hearts were investigated by serial sectioning of their atrioventricular conduction systems. All defects were divided into perimembranous or muscular types as previously suggested by Soto et al. The distinguishing feature of the perimembranous defect was that the central fibrous body formed part of its rim, this fact indicated that the conduction tissue was always to the right of the surgeon's hand when the defect was approached through the right atrium. The precise relationship of the ventricular conduction tissues varied depending upon whether the perimembranous defect extended into the inlet, trabecular or outlet components of the muscular septum. The nonbranching bundle was closest to the septal rim in the inlet and trabecular defects, frequently being buried in a remnant of the interventricular membranous septum. However, in these defects the nonbranching and branching bundles were also found in other specimens remote from the septal crest, yet were carried on the left ventricular aspect of the septum. In perimembranous inlet defects, the penetrating bundle detoured deep into the central fibrous body. In perimembranous outlet defects, the conduction tissues were remote from the septal crest. In contrast to these findings, the conduction tissues were away from the edges of the defects in trabecular and outlet muscular defects. In conclusion, in the perimembranous inlet defect, the placement of the sutures on the annulus of tricuspid valve should be avoided in view of its abnormal long penetrating bundle.  相似文献   
944.
脑后部可逆性脑病综合征的CT、MRI诊断   总被引:18,自引:0,他引:18  
目的探讨CT、MRI在诊断脑后部可逆性脑病综合征(PRES)中的价值。方法8例女性PRES患者中6例为孕妇,1例肺癌手术后化疗患者,1例高血压患者,均行MR静脉成像(MRV)、T1WI、T2WI、水抑制序列(FLAIR)成像及扩散加权成像(DWI);其中2例行CT平扫,5例行增强MRI及三维增强MR血管成像(3DCEMRA)。结果CT示病灶呈低密度,边界不清。8例患者MRV显示脑静脉、静脉窦通畅,无狭窄、异常扩张及血栓形成征象。MRI显示双侧顶枕叶(8例)、基底节区(2例)、额叶(4例)多发异常信号,主要位于双侧顶枕叶皮质下白质内,3例患者皮质亦受累。在T1WI病灶呈等或略低信号,T1WI及FLAIR呈高信号,以FLAIR像显示皮质病变为佳。DWI显示大部分病灶呈等信号,表观扩散系数(ADC)图呈等或高信号。部分病灶DWI及ADC图均表现为高信号。随访MRI显示所有患者病灶范围、数目逐渐变小、减少。5例行增强扫描患者显示病灶呈轻度强化,3D CEMRA显示强化沿双侧大脑前动脉、大脑中动脉及大脑后动脉终末支分布,部分呈“葡萄状”。随访增强扫描显示病灶强化范围及程度逐渐缩小、消失。结论FRES好发于顶枕叶白质,但也可见于基底节、额叶及脑皮质。病变为血管源性水肿,增强T1WI及3D CEMRA显示病灶有可逆性强化。以MRFLAIR及T2WI序列显示病灶最佳。  相似文献   
945.
We report a protracted course of disseminated candidiasis due to Candida tropicalis in a 17-year-old man with acute lymphocytic leukemia. Despite adequate antifungal therapy (amphotericin B), C. tropicalis was recovered from biopsy specimens 25 days (skin) and 109 days (kidney) after the first positive blood cultures. While blood cultures became negative for C. tropicalis 11 days after the initiation of treatment, mannanemia persisted and became negative only after 130 days of antifungal therapy. Thus, antigen assays provided indicators of antifungal response. Differential diagnosis was difficult for this patient with the observation of persistent lesions in image studies. With positive results of antigen assays, an invasive procedure might be avoided and preemptive antifungal treatment could be initiated in a timely manner. Anti-mannan antibody remained undetectable up to 164 days after first positive blood culture despite the patient's recovery from neutropenia and recruitment of neutrophils in the tissue (skin).  相似文献   
946.
A bstract Dynamic cardiomyoplasty (DCM) involves the electrical stimulation of a pedicled latissimus dorsi muscle flap wrapped around the failing ventricle as a means of cardiac assist. To further elucidate a potential neurohumoral mechanism for improvement of cardiac output after myoplasty, we evaluated the hemodynamic effects of in situ stimulation of the latissimus dorsi muscle (in the absence of cardiomyoplasty). In seven mongrel dogs, a nerve cuff electrode (Medtronic 6901) was placed around the left thoracodorsal nerve (TDN). This was attached to a pulse generator (Medtronic, Itrel 7420), delivering a 4.0 volt, 0.19 second on, 0.81 second off, 33 Hz, 210 microsecond pulse width, cyclic bursts similar to that used in DCM. Stroke volume index (SVI) and other hemodynamic parameters as well as plasma norepinephrine (NE) levels were measured at five stages: baseline, stimulator on at 0, 2, and 5 minutes, and stimulator off at 30 minutes after. The animals were then subjected to 4 weeks of rapid pacing at 240 beats/min (Medtronic 8329) to induce heart failure, and as the rapid pacing was discontinued, measurements were repeated as above. After rapid pacing, cardiac function was significantly depressed, and NE was elevated (133 ± 69 versus 500 ± 353 pg/mL, p < 0.05). In the normal hearts, TDN stimulation increased SVI, heart rate, systemic pressure, and NE levels. In heart failure, however, no significant changes in cardiac function and NE levels were noted. In conclusion, our data indicate that in the normal hearts, afferent impulses from TDN stimulation alone may augment cardiac function by means of a neurohumoral effect that is not seen in severe heart failure. The implications of these findings in DCM are discussed.  相似文献   
947.
Abdominal sonography for the detection of hemoperitoneum has become increasingly popular as a screening test for visceral injury after blunt trauma. The purpose of this study was to determine the frequency, severity, and clinical significance (outcome) of abdominal organ injuries that occur without hemoperitoneum on the initial evaluation of blunt abdominal trauma patients.During a 12-month period, 3392 blunt trauma patients were admitted to our center. Sonographic studies were performed as an initial screening evaluation to determine the presence of hemoperitoneum in 772 (22.7%) of these patients. Abdominal visceral injuries were verified by computed tomography (CT) or surgery in 196 (5.8%) of all blunt trauma admissions. Sonography, CT, and operative findings were reviewed to determine the presence or absence of hemoperitoneum in patients with abdominal injury. Patients with abdominal visceral injury without hemoperitoneum were further analyzed to identify the type of injury and the management required.A total of 246 abdominal injuries were identified in 196 patients. Fifty (26%) patients with abdominal visceral injuries diagnosed by admission CT scan had no evidence of hemoperitoneum. Admission sonography performed in 15 (30%) of these 50 patients also showed no evidence of hemoperitoneum. Visceral injuries detected by CT in the patients without hemoperitoneum included 22 of 100 splenic injuries (22%), 18 of 91 hepatic injuries (20%), 12 of 26 renal injuries (46%), and 1 of 9 mesenteric injuries (11%). Surgery was required to manage injuries in 10 of these patients.Up to 26% of blunt trauma patients with abdominal visceral injuries do not have associated hemoperitoneum identified on admission abdominal CT or sonography. Dependence on hemoperitoneum as the sole criterion of abdominal visceral injury after blunt trauma will result in falsely negative examinations and will miss potentially significant injuries.  相似文献   
948.
949.
The prevalence and prognostic significance of spontaneous bacterial peritonitis were prospectively studied in a series of 82 acute hepatitis patients decompensated with ascites. The in-hospital prevalence of spontaneous bacterial peritonitis was 31.7% (26 of 82 patients). Twenty cases were culture positive, including one with multiple isolates, and six cases were culture negative. E. coli and Klebsiella pneumoniae were the most common pathogens, accounting for 71.4% (15 of 21) of the total isolates, whereas only 9.5% were gram-positive organisms. No significant difference in the age, sex, cause of acute hepatitis, liver biochemistry, prothrombin time and ascites fluid concentration of total protein was noted between patients with spontaneous bacterial peritonitis and those without spontaneous bacterial peritonitis, except that bacteremia was recognized significantly more frequently in the former (57.7% or 15 of 26 patients) than in the latter (25.0% or 14 of 56 patients, p less than 0.005). In addition, patients with spontaneous bacterial peritonitis, when compared with those without spontaneous bacterial peritonitis, were more likely to have kidney failure (57.7% vs. 30.4%, p less than 0.05) and had a significantly higher mortality rate (73.1% vs. 39.3%, p less than 0.01). Among patients without spontaneous bacterial peritonitis, the prevalence of kidney failure and gastrointestinal hemorrhage and the mortality rate in patients with bacteremia (57.1%, 64.3% and 71.4%, respectively) were significantly higher than in those without bacteremia (21.4%, 19.0% and 28.6%, respectively; p less than 0.05, p less than 0.01 and p less than 0.01, respectively). In conclusion, 31.7% of severe acute hepatitis patients with ascites were recognized as having spontaneous bacterial peritonitis; the other 17.1% had bacteremia.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
950.
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