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31.
Technical improvements, such as mechanical lithotripsy, stenting or nasobiliary drainage, and wire-guided cannulation, have reduced the risk of complications in endoscopic sphincterotomy. To determine the extent of this reduction in risk, we assessed the medical records of 1352 patients with common bile duct stones in whom the procedure was conducted. Complications examined were: acute cholangitis and pancreatitis. Stone clearance was achieved in 1256 patients (92.8%), with an overall morbidity rate of 7.7% and a mortality rate of 0.15%. One hundred and forty-two patients had stones with a diameter greater than 20mm; 97 of these patients did not undergo lithotripsy. Cholangitis occurred in 10 of these 97 patients (10.3%), whereas, in the 45 patients who underwent lithotripsy, there were no cases of cholangitis (P=0.02). Stone removal was not immediately accomplished or attempted in 396 patients. In 82 of these patients in whom a stent or a nasobiliary drain was placed in the common bile duct, the incidence of cholangitis was 1.2%, significantly less (P=0.045) than the incidence of 6.4% in the other 314 patients given no stenting or nasobiliary drain. To overcome difficult cannulation, precut sphincterotomy was conducted in 134 patients and wireguided sphincterotomy, a recently introduced procedure, was conducted in 55 patients. When the precutting technique was used, the incidence of acute pancreatitis was significantly higher (8/134; 6.0%) than that in the patients in whom the standard procedure was conducted, i.e., neither the precut technique nor wire-guided ES was used (23/1218; 1.9%) (P=0.008). There were no cases of pancreatitis in the 55 patients in whom wire-guided sphincterotomy was performed, although the difference was not statistically significant because of the small number of patients (P=0.06). Based on these findings, we conclude that improved technologies have led to a significant reduction of complications in endoscopic sphincterotomy.  相似文献   
32.
Abstract:  Carbohydrate (Carb) counting is a meal planning approach for patients with diabetes mellitus that focuses on carbohydrate as the primary nutrient affecting postprandial glycemic response. The concept of carb counting is not new. In the early 1990`s the Diabetes Control and Complications Trial (DCCT) used carb counting as one of its education tools. More recently, short acting insulin analogues and insulin pumps have made the role of carb counting important and popular. Carb counting can be used in conjunction with a meal plan to set carbohydrate targets at each meal and snack. It is also used, perhaps more commonly, to estimate carbohydrate intake and adjust insulin around mixed meals and snacks using insulin to carbohydrate ratio. This effectively addresses the variable eating habits of most children and adolescents. The method may be adapted for patients who use a conventional insulin regimen and may meet the needs of patients who use multiple daily injections (MDI) or an insulin pump. Carb counting can make food planning flexible and enjoyable for patients, and the meal planning approach is very important for the physical growth and psychological development of children with diabetes. This paper describes the importance of carb counting for childhood diabetes as well as some of the special aspects associated with it.  相似文献   
33.
To elucidate the mechanism(s) by which Vav3, a new member of the Vav family proteins, participates in B cell antigen receptor (BCR) signaling, we have generated a B cell line deficient in Vav3. Here we report that Vav3 influences phosphoinositide 3-kinase (PI3K) function through Rac1 in that phosphatidylinositol-3,4,5-trisphosphate (PIP3) generation was attenuated by loss of Vav3 or by expression of a dominant negative form of Rac1. The functional interaction between PI3K and Rac1 was also demonstrated by increased PI3K activity in the presence of GTP-bound Rac1. In addition, we show that defects of calcium mobilization and c-Jun NH2-terminal kinase (JNK) activation in Vav3-deficient cells are relieved by deletion of a PIP3 hydrolyzing enzyme, SH2 domain-containing inositol polyphosphate 5'-phosphatase (SHIP). Hence, our results suggest a role for Vav3 in regulating the B cell responses by promoting the sustained production of PIP3 and thereby calcium flux.  相似文献   
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35.
Leukoaraiosis correlates with cerebral hypoperfusion in vascular dementia   总被引:6,自引:0,他引:6  
Leukoaraiosis quantified by computerized densitometric measurements of reduced Hounsfield numbers was correlated with local cerebral blood flow on the same computed tomographic images of 35 patients with multi-infarct dementia and 16 age-matched elderly normal volunteers. The ratio for area of frontal leukoaraiosis to total area of parenchyma among the patients was significantly greater than that among the normal volunteers (5.8 +/- 2.3% compared with 3.1 +/- 1.3%, p less than 0.001). Severity of leukoaraiosis around the frontal horns of the lateral ventricles correlated significantly with severity of leukoaraiosis of the centrum semiovale adjacent to the bodies of the lateral ventricles. Cerebral blood flow values for all representative cerebral regions except the parietal white matter were reduced among the patients compared with the normal volunteers. Multivariate regression analysis revealed that reduced cerebral perfusion in the putamen and thalamus correlated significantly with the severity of leukoaraiosis. Cerebral hypoperfusion in territories supplied by deep penetrating arteries may contribute to the pathogenesis of leukoaraiosis.  相似文献   
36.
Thirty-eight patients with convexity lesions were studied prospectively with the two-dimensional time-of-flight (2D-TOF) magnetic resonance angiography (MRA) method. Of these 21 cases had additional surface anatomy scanning (SAS) and 7 cases had three-dimensional phase contrast (3D-PC) MRA. The findings were compared during surgery, and the predictability of 2D-TOF evaluated. 2D-TOF was obtained with 2 mm slice thickness after the administration of contrast media for routine magnetic resonance imaging (MRI). Cortical veins were visualized with a good resolution with a scan time of only 5 minutes. The tumor was also visible in the background, due to enhancement, and thus the tumor-vessels relation was shown. Slow-flow vessels were also adequately seen. SAS was done at the same sitting with fast spin echo (FSE) with a scan time of 3 minutes. Once both images were incorporated, information on gyri and their relation to the lesions and vasculature could be obtained from a single image. We found 2D-TOF alone, or at times in combination with SAS, useful for planning of operation for convexity lesions.  相似文献   
37.
Lesions in the thalamus or basal ganglia have rarely been reported in acute disseminated encephalomyelitis (ADEM). We experienced 2 cases of ADEM, in which MRI showed lesions in the thalamus or basal ganglia. Case 1, a 4-year-old boy, had gait disturbance, hyperesthesia and hyperreflexia. MRI (T2 weighted image) showed multiple high intensity areas in the right frontal lobe, bilateral parietal lobes and bilateral thalami. Case 2, a 4-year-old girl, complained of gait disturbance following a febrile episode, and displayed hyperreflexia. Several days later, she had visual disturbance of the left eye. MRI (T2 weighted image) revealed multiple high intensity areas in the dentate nucleus of left cerebellum, left occipital lobe, bilateral caudate nuclei, and the anterior part of bilateral lenticular nuclei. In both cases, CT could not demonstrate these lesions. Both of them were treated with corticosteroid and recovered rapidly. They had no recurrence. MRI is useful in diagnosis and follow-up of ADEM and may reveal lesions other than cerebral or cerebellar white matters.  相似文献   
38.
Toluene in blood as a marker of choice for low-level exposure to toluene   总被引:1,自引:1,他引:0  
The validity of two new biological exposure markers of toluene in blood (TOL-B) and toluene in urine (TOL-U) was examined in comparison with that of the traditional marker of hippuric acid in urine (HA-U) in 294 male workers exposed to toluene in workroom air (TOL-A), mostly at low levels. The exposure was such that the geometric mean for toluene was 2.3 ppm with a maximum of 132 ppm; the workers were also exposed to other solvents such as hexane, ethyl acetate, styrene, and methanol, but at lower levels. The chance of cutaneous absorption was remote. Higher correlation with TOL-A and better sensitivity in separating the exposed workers from the nonexposed subjects were taken as selection criteria. When workers exposed to TOL-A at lower concentrations (< 50 ppm, < 10 ppm, < 2 ppm, etc.) were selected and correlation with TOL-A was examined, TOL-B showed the largest correlation coefficient which was significant even at TOL-A of < 1 ppm, whereas correlation of HA-U was no longer significant when TOL-A was < 10 ppm. TOL-U was between the two extremes. The sensitivities of TOL-B and TOL-U were comparable; HA-U showed the lowest sensitivity. Thus, it was concluded that TOL-B is the indicator of choice for detecting toluene exposure at low levels.  相似文献   
39.
Aim:  To compare the clinical outcomes of cryopreserved-thawed embryo transfer among patients with a normal menstrual cycle who had natural or hormone-replacement cycles.
Methods:  From January 2004 to June 2006, cryopreserved embryos following conventional in vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) were thawed and transferred in a total of 720 natural cycles and 136 hormone-replacement cycles.
Results:  Cryopreserved-thawed embryo transfer in patients who had a natural or hormone-replacement cycle resulted in clinical pregnancy in 43.1% and 40.4%, respectively; a rate of miscarriage of 14.5% and 23.6%, respectively; and a rate of ongoing pregnancy and delivery of 36.5% and 30.9%, respectively. None of these differences were statistically significant.
Conclusions:   Patients with a normal menstrual cycle who have natural or hormone-replacement cycles can be expected to have comparable clinical outcomes with cryopreserved-thawed embryo transfer. (Reprod Med Biol 2007; 6 : 53–57)  相似文献   
40.
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