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991.
A prospective study of 62 chemotherapy-induced neutropenic episodes in patients with acute leukaemia was conducted to determine the incidence and causes of abdominal infections, and to assess the diagnostic value of the combined use of ultrasonography (US) and microbiology. Each patient underwent US of liver, gallbladder and complete bowel before chemotherapy, on days 2-4 after the end of chemotherapy and in cases of fever, diarrhoea or abdominal pain. US was combined with a standardized clinical examination and a broad spectrum of microbiological investigations. From January to August 2001, 243 US examinations were performed. The overall incidence of abdominal infectious diseases was 17.7% (11 out of 62, 95% confidence interval (CI): 9-29%). Four patients (6.5%) developed neutropenic enterocolitis; two of them died, two survived. Bowel wall thickening (BWT) > 4 mm in these four patients ranged from 5.8 to 23.6 mm and was detected only in one patient with mucositis. In three other patients (4.8%) Clostridium difficile, and in one patient (1.6%) Campylobacter jejuni, caused enterocolitis without BWT. Cholecystitis was diagnosed in three patients (4.8%) and hepatic candidiasis was strongly suspected in one patient. Abdominal infections caused by gastroenteritis viruses, cytomegalovirus (CMV) or Cryptosporidium were not observed. We conclude that in neutropenic patients with acute leukaemia receiving chemotherapy: (i) BWT is not a feature of chemotherapy-induced mucositis and should therefore be considered as sign of infectious enterocolitis; (ii) viruses, classic bacterial enteric pathogens (Salmonella, Shigella, Yersinia, Campylobacter, Aeromonas, Vibrio subsp., enterohaemorrhagic Escherichia coli) and Cryptosporidium have a very low incidence; and (iii) abdominal infections may be underestimated when US is not used in every patient with abdominal pain.  相似文献   
992.
Objective  To assess the efficacy of chloroquine in the treatment of Plasmodium vivax malaria in in Dawei District, southern Myanmar.
Methods  Enrolled patients at Sonsinphya clinic >6 months of age were assessed clinically and parasitologically every week for 28 days. To differentiate new infections from recrudescence, we genotyped pre- and post-treatment parasitaemia. Blood chloroquine was measured to confirm resistant strains.
Results  Between December 2002 and April 2003, 2661 patients were screened, of whom 252 were included and 235 analysed. Thirty-four per cent (95% CI: 28.1–40.6) of patients had recurrent parasitaemia and were considered treatment failures. 59.4% of these recurrences were with a different parasite strain. Two (0.8%) patients with recurrences on day 14 had chloroquine concentrations above the threshold of 100 ng/ml and were considered infected with chloroquine resistant parasites. 21% of failures occurred during the first 3 weeks of follow-up: early recurrence and median levels of blood chloroquine comparable to those of controls suggested P. vivax resistance.
Conclusions  Plasmodium vivax resistance to chloroquine seems to be emerging in Dawei, near the Thai-Burmese border. While chloroquine remains the first-line drug for P. vivax infections in this area of Myanmar, regular monitoring is needed to detect further development of parasite resistance.  相似文献   
993.
994.
The marked female predominance in cases of idiopathic chronic cough and its association with mild chronic lymphocytic airway inflammation suggests an underlying autoimmune process. We set out to test the hypothesis that idiopathic chronic cough is associated with other organ-specific autoimmune diseases in a case control study. Twenty-two patients with idiopathic chronic cough and 65 community-matched controls for age and sex who responded to a self-administered questionnaire were asked about the presence of autoimmune disease, other medical problems and drug history. All subjects were invited to have a blood test for an autoimmune screen. Thirteen out of 22 (59%) patients with idiopathic chronic cough and eight out of 65 (12%) age- and sex-matched controls reported organ-specific autoimmune disease (odds ratio 8.8; 95% confidence interval 2.4-31.8, P<0.001). Organ-specific autoantibodies were present in a significantly higher proportion of cases than controls (40% vs. 13%; P = 0.047). These findings suggest a relationship between idiopathic chronic cough and organ-specific autoimmunity.  相似文献   
995.
The absence or very low levels of plasminogen cause a rare disabling disease called ligneous conjunctivitis, characterized by the growth of fibrin-rich pseudomembranes in the conjunctiva and on other mucosal surfaces. Several mutations have been detected in the plasminogen gene of patients affected with ligneous conjunctivitis. The human plasminogen gene, located on chromosome 6, has a marked homology with the genes belonging to the plasminogen-apo(a) family, and with a number of pseudogenes and plasminogen-like genes located on chromosome 2. This work describes a series of nucleotide variations related to genes other than the plasminogen one, found during the genetic characterization of plasminogen defect in two unrelated patients with ligneous conjunctivitis. The results of automated sequences of each exon and intron-exon boundaries were compared with those of the human plasminogen gene from the NCBI gene bank. In particular, a co-amplified gene on chromosome 2 mimicking a 14 bp deletion in exon 5 of the plasminogen gene was identified by sequencing two different bands obtained from a long run of the PCR exon 5 product in NuSieve agarose gel, and by PstI restriction enzyme analysis of the same amplicons. Moreover, 21 single nucleotide exchanges due to plasminogen-like genes co-amplification were observed, namely one in exon 1, two in exon 4, three in exons 3, 5 and 16, four in exon 13, and five in exon 17. In conclusion, these data confirm the difficulty of plasminogen genetic analysis and may help researchers to better identify the true plasminogen gene mutations causing molecular defects.  相似文献   
996.
Activating mutations in the KCNJ11 gene encoding for the Kir6.2 subunit of the beta-cell ATP-sensitive potassium channel have recently been shown to be a common cause of permanent neonatal diabetes. In 80% of probands, these are isolated cases resulting from de novo mutations. We describe a family in which two affected paternal half-siblings were found to be heterozygous for the previously reported R201C mutation. Direct sequencing of leukocyte DNA showed that their clinically unaffected mothers and father were genotypically normal. Quantitative real-time PCR analysis of the father's leukocyte DNA detected no trace of mutant DNA. These results are consistent with the father being a mosaic for the mutation, which is restricted to his germline. This is the first report of germline mosaicism in any form of monogenic diabetes. The high percentage of permanent neonatal diabetes cases due to de novo KCNJ11 mutations suggests that germline mosaicism may be common. The possibility of germline mosaicism should be considered when counseling recurrence risks for the parents of a child with an apparently de novo KCNJ11 activating mutation.  相似文献   
997.
P-glycoprotein (P-gp), lung resistance-related protein (LRP) and multidrug resistance-associated protein (MRP) expression, and blast cell intracellular daunorubicin accumulation (IDA) were evaluated in 95 previously untreated cases of adult acute lymphoblastic leukaemia (ALL) using flow cytometry. Forty-five out of 95 (47%) patients were P-gp positive (+), 12/66 (18%) were LRP+ and 11/66 (17%) were MRP+. Eighteen out of 66 (28%) patients showed a simultaneous multidrug resistance (MDR)-related protein expression higher than controls for more than one protein, while 24/66 (36%) cases did not overexpress any protein. Twenty-one out of 24 (87%) cases overexpressing at least one MDR-related protein had a defect in accumulating daunorubicin into their blast cells, while only 4/24 (16%) cases who did not overexpress any protein had similar features. The complete remission rates were similar in MDR-positive and -negative (-) patients but relapses within 6 months were more frequent in P-gp+ cases, and therefore the disease-free survival duration was shorter in P-gp+ than in P-gp- patients (P = 0.01). The number of MRP+ and/or LRP+ cases was too small to be able to draw any conclusion on their role in affecting or predicting therapy outcome. In conclusion, P-gp overexpression associated with a defect in daunorubicin accumulation is a frequent feature in adult ALL at onset and seems to be related to poorer therapy outcome and, consequently, a shorter disease-free survival. LRP and MRP overexpression seems to be a rare event and no conclusion can be drawn on its prognostic role.  相似文献   
998.
PURPOSE: To assess flow velocities in the cerebral arteries after carotid artery stenting (CAS) in patients with unilateral versus bilateral lesions and analyze velocities in patients with neurological complications after CAS. METHODS: Ninety-two patients (68 men; mean age 63.2 +/- 8.4 years, range 44-82) with internal carotid artery (ICA) stenoses were divided according to unilateral (group I, n = 72) or bilateral (group II, n = 20) disease. Fifty age- and gender-matched patients without lesions in the extra- or intracranial arteries served as a control group. Transcranial color-coded Doppler ultrasound was performed prior to and within 24 hours after CAS in the test groups; systolic velocities were assessed ipsilateral (i) and contralateral (c) to the CAS site in the middle cerebral artery (MCA) and anterior cerebral artery (ACA). RESULTS: Collateral flow via the anterior communicating artery (ACoA) was found in all group-II patients and 90% of group-I patients. After CAS, collateral flow through the ACoA ceased, and the velocity increased by 26% in the iMCA in group I compared to controls (p < 0.001). In group II, iMCA flow increased by 30% (p < 0.001) and flow via the ACoA (p < 0.001) increased, resulting in normalization of cMCA velocities (p = 0.928). In 89 (96.7%) subjects, CAS was uncomplicated. Hyperperfusion syndrome occurred in 2 (2.2%) patients, both with bilateral ICA stenoses; 1 (1.1%) transient ischemic attack was seen in a patient with unilateral disease. In the patients with hyperperfusion syndrome, the MCA velocities were 2.7- and 7.4-fold higher, respectively, versus before CAS and 2-fold higher than in controls. CONCLUSION: Uncomplicated CAS results in an iMCA velocity increase >25% compared to controls. MCA velocities in hyperperfusion syndrome were greatly increased versus before CAS and in controls.  相似文献   
999.
Childhood obesity represents a complex disease with a well-known cardiometabolic burden including fatty liver, type 2 diabetes, metabolic syndrome, and cardiovascular disease. From a pathogenic point of view, insulin resistance (IR) represents the key factor underlying the spectrum of these obesity consequences. As observed in adults, recent data supported the occurrence of microalbuminuria (MA) as marker of early kidney dysfunction and its potential link with cardiometabolic factors also in children with obesity. In fact, a well-documented pathophysiological hypothesis both in adults and children supported an intimate correlation with the major feature of obesity such as IR through the influence of insulin on renal hemodynamics. Based on the clinical and prognostic relevance of this relationship in daily practice (including an increased risk of chronic kidney disease development overtime), more scientific attention needs to be paid to the evaluation of early kidney damage in children with obesity. In this paper, we attempt to address three debated questions regarding the intriguing liaison between IR and MA in children with obesity: (1) What is the prevalence of pediatric MA? (2) What is the state of art of MA in children with obesity? and (3) Is there a link between IR and MA in children with obesity?  相似文献   
1000.
Purpose

To compare the accuracy of Contrast-Enhanced Spectral Mammography (CESM), MG, US, and breast MRI in estimating the size of breast lesions requiring surgery. The postoperative histology size of the lesion was used as the gold standard.

Material and methods

Two hundred thirty-three non-benign lesions in 189 patients were included in the analyses. All the selected patients underwent CESM and at least one other conventional diagnostic exam (US, MG, or MRI). Subsequently, all the patients underwent surgery preceded by cytological/histological examination. The largest diameter of the lesion at imaging was measured by a radiologist with more than 10 years’ experience and then compared with the size of the lesion in the histological sample at the surgery (gold standard).

Results

Among the 233 breast lesions, 196 were evaluated with US, 206 with MG and 160 with MRI. We found no statistically significant differences between size measurements using CESM and MRI compared with the measurements at the surgery (p value 0.63 and 0.51), whereas a significant difference was found for MG and US (p?<?0.001).

Conclusion

CESM is a reliable method for estimating the size of breast lesions: its performance seems superior to US and MG and comparable to MRI.

  相似文献   
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