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21.
Midgut malrotation,the reliability of sonographic diagnosis   总被引:4,自引:0,他引:4  
We are unaware of any other anatomical study which deals with normal variations in the relationship between the superior mesenteric artery (SMA) and the superior mesenteric vein (SMV). In our investigation in the majority of cases, the SMV lies to the right of the SMA. It has been suggested that ultrasonographic demonstration of a left sided SMV, is characteristic of midgut malrotation so a prospective study was undertaken in order to try to correlate the position of the mesenteric vessels on Ultrasound with the radiological diagnosis of midgut malrotation on upper GI series. 427 children (95% infants) who were planned for upper GI investigation, have had color Doppler U.S. of the mesenteric vessels before the barium study. In 67 cases, the mesenteric vessels were obscured by intestinal gas. Among them, there were 2 cases of malrotation. Three different positions of the mesenteric vessels were found in the 360 remaining cases. 1) A left sided SMV was found in 4% of the cases, all had midgut malrotation on X-rays and at surgery. 2) A mesenteric vein anterior to the SMA was found in 5% of the cases, 28% had midgut malrotation. 3) A normal right sided SMV was found in 91% of the cases. However 3% of these had midgut malrotation. There are anatomical variations in the position of the mesenteric vessels and a normal relationship between SMA and SMV does not ecxclude the possibility of intestinal malrotation. Nevertheless, ultrasound remains a useful noninvasive screening technique for the diagnosis of midgut malrotation.Presented at the IPR meeting in Stockholm, May 1991. Selected for publication by an International Group of the ESPR  相似文献   
22.
The safety, predictability, and ease of intravenous administration of nitroglycerin (NTG) have been firmly documented. In recent years, intravenous NTG has come to the attention of the obstetrician as a potent uterine relaxant. Intravenous nitroglycerin has been used to relax the uterus during manual extraction of retained placenta and to permit replacement of a contracted, completely prolapsed, inverted uterus. The use of this agent as a tocolytic has previously been reported in cesarean delivery of twins, in cases of intra partum external cephalic version, and for internal intrapartum podalic version of the second twin. This new procedure was also used for fetal head entrapment after vaginal breech delivery. The authors report a review of the literature about this subject. Received: February 1997 / Accepted: 20 June 1997  相似文献   
23.
NAD(P)H:quinone oxidoreductase 1 (NQO1) is a detoxification enzyme that protects cells against oxidative stress and toxic quinones. A polymorphism (C609T) in the gene produces in the heterozygous individuals (C/T) a reduction and in those homozygous for the variant allele (T/T) the abolishment of NQO1 protein activity. To assess whether NQO1 inactivating polymorphism (CT/TT) was a possible risk factor for infant acute lymphoblastic leukemia (iALL), we investigated the distribution of NQO1 genotype in 50 iALL patients, 32 with MLL gene rearrangements (MLL+) and 18 without (MLL-). As controls, 106 cases of pediatric ALL (pALL), and 147 healthy subjects were also studied. Compared to normal controls, the frequency of the low/null activity NQO1 genotypes was significantly higher in the iALL MLL- (72 vs 38%, P=0.006; odds ratio (OR) 4.22, 95% confidence interval (CI) 1.43-12.49), while no differences were observed in iALL MLL+ (44 vs 38%, P=0.553; OR 1.26, 95% CI 0.58-2.74). Similar results were observed when pALL were used as control. Our results indicate that only the iALL patients without MLL rearrangements had a significantly higher frequency of NQO1 genotypes associated with low/null activity enzyme, suggesting a possible role for NQO1 gene as an MLL-independent risk factor, in the leukemogenic process of this subtype of iALL.  相似文献   
24.
25.
The World Health Organization 2008 Classification emphasizes myeloperoxidase (MPO) detection as sufficient for assigning a blast population to the myeloid lineage. Published MPO positivity thresholds are 10% for flow cytometry (FCM) but 3% for cytochemistry. Here we re‐evaluated the FCM‐MPO threshold by comparing retrospectively 128 acute lymphoblastic leukaemias and 75 acute myeloid leukaemias without maturation, all assessed by benzidine‐based cytochemistry. A 13% threshold was found to be relevant using an isotype control as background‐reference (sensitivity 95·1%, specificity 91·7%). Residual normal lymphocytes proved to be an advantageous alternative reference, a threshold of 28% yielding improved 97·4% sensitivity and 96·1% specificity.  相似文献   
26.
We hypothesized that cryopreservation and incubation in conditions that mimic the female genital tract following insemination increases the susceptibility of ram sperm DNA to denaturation. Ram sperm samples (n = 12) underwent the sperm chromatin structure assay (SCSA) and semen quality tests, including motility parameters, viability, and chlortetracycline fluorescence (CTC) patterns. We also assessed correlations between SCSA variables and semen quality parameters. Analyses were performed for both fresh and cryopreserved samples at 0, 3, and 20 hours of incubation in synthetic oviductal fluid (SOF; 39 degrees C, 5% CO(2)). The SCSA variables, mean alpha t (X alpha(t)) and standard deviation of alpha t (SD alpha(t)), were higher because of cryopreservation (P <.05, P <.001, respectively) after 20 hours in SOF. For both fresh and frozen spermatozoa, SCSA values (X alpha(t), SD alpha(t), and the percentage of cells outside the main population of alpha(t) [%COMP alpha(t)]) increased during incubation in SOF. Motility was negatively correlated with both SD alpha(t) and %COMP alpha(t), ranging from -0.39 (P <.01) to -0.59 (P <.001) for both fresh and cryopreserved semen; viability also was negatively correlated with X alpha(t), SD alpha(t), or %COMP alpha(t) (-0.36; P <.05, -.40 and -.46; P <.01, respectively) in fresh semen. The %COMP alpha(t) was positively correlated to the percentage of CTC pattern AR (P <.001) and negatively correlated to the percentages of patterns F and B (-0.33 to -0.60, P <.05 to P <.001). Variation among ejaculates within ram was observed (P <.01). Cryopreservation clearly facilitates DNA damage in physiological conditions. The low to moderate correlations between SCSA variables and classical semen quality parameters indicate that the SCSA provides additional information to standard tests for evaluating ram sperm quality.  相似文献   
27.
Anemia is a common complication of chronic kidney disease (CKD) in predialysis stage. Iron deficiency is more common than in normal patients and plays a key role in the genesis of anemia. Its correction avoids the use of erythropoiesis stimulating agents (ESA) or reduces their dosage. Treatment with oral iron is often poorly tolerated and ineffective, necessitating the use of intravenous iron. New forms of injectable iron allow the use of high doses and correct iron deficiency in a single administration with consequent preservation of venous capital and lower costs. We studied the effectiveness of iron dextran of low molecular weight (LMWID) in high doses to correct iron deficiency and treat anemia in predialysis CKD patients. Twenty-nine doses of 500 to 1600 mg were administered to 25 patients followed for CKD (GFR between 60 and 10 ml/min per 1.73 m2), selected on biological criteria of iron deficiency defined by a ratio of transferrin saturation (TSAT) < 20% and/or serum ferritin of less than 100 μg/L. Patients received treatment by ESA in 16 cases out of 29. One month after treatment, hemoglobin (Hb) increased significantly (11.4 ± 1.6 vs 10.4 ± 1.4 g/dL, P = 0.0003) along with a significant increase in TSAT (21.3 ± 7.3 vs 13.3 ± 3.8%, P = 0.000003) and serum ferritin (286 ± 253 vs 91 ± 60 μg/L, P = 0.00005). Six patients had a serum ferritin greater than 500 μg/L after treatment, which may put them at risk of iron overload. Their serum ferritin was higher than the rest of the population before treatment, while the TSAT was no different, reflecting a functional deficiency. Their hemoglobin did not increase after treatment in contrast to the rest of the population suggesting the unavailability of iron for erythropoiesis with accumulation in the reticuloendothelial system. Renal function did not change significantly and there were no cases of acute renal failure. No immediate side effect was observed. Three patients presented delayed reactions to such self-limiting myalgia and arthralgia. No venous inflammatory reaction was noted. The administration of high doses of LMWID is effective in treating anemia of CKD in the predialysis stage with a satisfactory tolerance, without affecting kidney function and helps preserve the venous capital. It should be reserved for patients whose serum ferritin is less than or equal to 150 μg/L.  相似文献   
28.
Klippel-Feil syndrome (KFS) is defined as a congenital fusion of at least two cervical vertebrae. Patients with KFS are known to be at high risk for spinal cord injury in case of cervical trauma even with weak kinetic. We report the case of a patient with C4–C5 and C6–C7 congenital fusion, harbouring C5–C6 post-traumatic spinal cord injury, associated with an odontoid fracture type 2 of Anderson and D’Alonzo classification following a motorbike accident.  相似文献   
29.
France attained ‘Officially Tuberculosis‐Free’ status in 2000. However, the Côte d’Or department (a French administrative unit) has since seen an increase in bovine tuberculosis (bTB) cases, with 35% of cases attributed to neighbourhood contamination. The aim of this study was to investigate the characteristics of neighbourhood contacts in an area affected by bTB in 2010, through the use of social network methods. We carried out a survey to determine the frequency and distribution of between‐herd contacts in an area containing 22 farms. Contacts were weighted, as not all types of contact carried the same risk of bTB transmission. Cattle movement was considered to be associated with the highest risk, but was not observed within the studied area during the study period. Contact with wild boars was the most frequent type of contact, but was associated with a very low risk. Direct cattle‐to‐cattle contacts in pasture and contacts with badger latrines were less frequent, but entailed a greater risk of M. bovis transmission. Centrality values were heterogeneous in these two networks. This would enable the disease to spread more rapidly at the start of epidemics than in a perfect randomly mixed population. However, this situation should also result in the total number of infected herds being smaller. We attributed 95% of the contacts to direct contact in pasture or contact with wild boars or badger latrines. Other kinds of contact occurred less frequently (equipment sharing, cattle straying) or did not occur at all (attendance at a show). Most of the contact types were correlated, but none was sufficient in itself to account for all contacts between one particular farm and its neighbours. Contacts with neighbours therefore represent a challenge for the implementation or improvement of control measures.  相似文献   
30.
Rapid detection of infection is critical to the containment and control of contagious pathogens. Passive surveillance, based on the detection of clinical signs through farmers’ observations and subsequent veterinarian notification, is the primary means of initially detecting an epizootic and for implementing control measures. The objective of this study was to analyse how the composition and structure of passive surveillance networks may impact epizootic spread and control. Three compositions of passive surveillance network were considered: (i) A veterinarian‐based surveillance network composed of farmers and veterinarians (the common passive surveillance network where each veterinarian follows up a group of holdings), (ii) a farmer‐based surveillance network composed of farmers only (the farmer plays the same role as in the preceding network as well as that of the veterinarian but his point of view is limited to his animals) and (iii) a hierarchical surveillance network composed of farmers, veterinarians and district‐level veterinarian specialists (in case of doubt, the local veterinarian calls the specialist veterinarian). We compared the efficacy of these different network types where actors have successively a structurally wider perspective than the preceding ones using a specific stochastic model for the spread of foot‐and‐mouth disease (FMD). The model was forced by actual data to generate realistic simulated FMD epizootics in France. Our results show that maintaining the presence of field veterinarians following‐up several holdings in breeding areas is fundamental and adding veterinarian specialists to passive surveillance networks could greatly enhance surveillance network efficacy.  相似文献   
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