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101.
A 11/2-year-old male child with past history of recurrent wheezing presented with a severe and refractory episode following a peanut aspiration. A bronchoscopy was done and the peanut removed. However, as the wheezing persisted a detailed evaluation was done which revealed a bronchogenic cyst. Surgical excision of the cyst was done and the child improved symptomatically. Congenital lesions need to be ruled out in infants and children with persistent and refractory wheezing  相似文献   
102.
This prospective study was undertaken to investigate the possibility of a concurrent outbreak of leptospirosis and dengue and to describe the clinical illnesses. From 20 June to 14 November 2002, children who presented to our hospital with a suspected diagnosis of leptospirosis or dengue were admitted. In every child with suspected leptospirosis, a screening latex agglutination test was carried out to detect anti-Leptospira antibodies. The diagnosis of leptospirosis was confirmed by a positive enzyme-linked immunosorbent assay (ELISA) test or microagglutination test. The diagnosis of dengue was confirmed by a positive IgM antibody capture ELISA test. Clinical features in the leptospirosis and leptospirosis-negative groups, and dengue and dengue-negative groups were analysed. Of 90 children screened, 15 (16.7 per cent) had leptospirosis. Two children with Weil's disease died and the remaining 13 responded well to intravenous penicillin. Five clinical features were significantly associated with leptospirosis, namely conjunctival suffusion (p=0.007), haemorrhage (p=0.020), abdominal pain (p=0.011), hepatosplenomegaly (p=0.044), and oedema (p=0.007). As the number of these five features concomitantly present increased, the chances of the child having leptospirosis also increased significantly (p<0.0001). Of 90 children screened, 16 (17.8 per cent) had dengue. All responded well to the treatment and went home. Two clinical features were significantly associated with dengue, namely arthralgia (p=0.020) and thrombocytopenia (p=0.001). If both these features were present, the chances of the child having dengue increased significantly (p=0.001). Our study shows that a concurrent outbreak of leptospirosis and dengue had occurred in the slums of Mumbai city.  相似文献   
103.
We present evidence that, in Escherichia coli, polar positional information is present at midcell independent of known cell division factors. In filamented cells, IcsA, which is normally polar, localizes at or near potential cell division sites. Because the cell pole is derived from the septum, the sites to which IcsA localizes in filaments correspond to future poles. IcsA localization to these sites is independent of FtsZ, MinCDE, septation, and nucleoid occlusion, indicating that positional information for the future pole is independent of cell division and chromosome positioning. Upon IcsA localization to these sites, septation is inhibited, suggesting that IcsA recognition of this polar positional information may influence cell division.  相似文献   
104.
105.
Summary. One DNA A (KA30) and five different DNA B components (KA21, KA22, KA27, KA28 and KA34) of a geminivirus, Mungbean yellow mosaic virus–Vigna (MYMV-Vig) were cloned from a pooled sample of field-infected Vigna mungo plants from Vamban, South India. MYMV-Vig DNA A (KA30) and one of the DNA B components (KA27) exhibited 97% and 95% sequence identities, respectively, to those of MYMV reported from Thailand. However, the DNA B components KA21, KA22, KA28 and KA34 exhibited only 71 to 72% sequence identity to MYMV DNA B. Co-existence of multiple DNA B components in field-infected V. mungo was proved by Southern and PCR analyses. Each of the five DNA B components was infective together with the DNA A upon agroinoculation. Agroinoculation with mixed cultures of Agrobacterium with partial dimers of DNA A and all five DNA Bs proved that all five DNA B components can co-infect a single V. mungo plant.A. S. K. and R. V. contributed equally to this work.  相似文献   
106.
Antiphospholipid antibodies--our experience   总被引:1,自引:0,他引:1  
Antiphospholipid antibodies (APA) have aroused multispeciality interests. In our study of 200 cases worked up for APA, we have used a few simple coagulation tests to detect lupus anticoagulant (LA) and ELISA to detect anticardiolipin antibodies. The positivity rate for LA among cases with recurrent pregnancy loss was 4.16% and for aCL 20.8%. The positivity rate for LA in patients with venous thrombosis was 6.2%, in arterial thrombosis was 7.14% and in SLE patients was 58.3%. In conclusion APAs are to be looked for in cases of recurrent pregnancy loss, thrombosis in people < 45 years of age without risk factors and SLE patients to assess the thrombotic risk and to decide on anti coagulant therapy for further management.  相似文献   
107.
The steroid hormone 1,25-dihydroxyvitamin D(3), [1,25(OH)(2)D(3), calcitriol], the active metabolite of vitamin D, exerts pleiotropic antitumor effects against several malignancies. However, the clinical use of this hormone is limited by hypercalcemia. 25-Hydroxyvitamin D(3), the prohormone of 1,25(OH)(2)D(3), is hydroxylated to the active hormone by the enzyme 25-hydroxyvitamin-1-alpha-hydroxylase [1 alpha(OH)ase]. 1 alpha(OH)ase is found primarily in the kidney, but also is expressed in the prostate, colon and other tissues. Using immunohistochemistry, we report that 1 alpha(OH)ase is highly expressed in both normal and malignant pancreatic tissue. Expression of this enzyme and enzymatic activity was also detected in four pancreatic tumor cell lines. 25(OH)D(3) inhibited the growth of three of four pancreatic cell lines in a manner that correlated with the level of induction of the cyclin-dependent kinase inhibitors p21 and p27 and with the induction of cell cycle arrest at the G(1)/S checkpoint. The growth of a cell line stably transfected with a mutant Ki-ras allele and of a second cell line with an endogenous Ki-ras activating mutation was also inhibited by 25(OH)D(3), indicating that activating Ki-Ras mutations, which occur in almost 90% of pancreatic adenocarcinomas, do not interfere with the growth-inhibitory effects of 25(OH)D(3). The expression of 1 alpha(OH)ase in normal and malignant pancreatic tissue and the antiproliferative effects of the prohormone in these cells, suggest that 25(OH)D(3) may offer possible therapeutic and chemopreventive options for pancreatic cancer.  相似文献   
108.
Kalns J  Roy A  Loeffler C  Wright JK 《Ostomy/wound management》2004,50(4):36-8, 40, 42 passim
As new wound care treatments become available, correct initial treatment selection and dynamic modification of regimens, based on wound response to treatment, must be applied to improve outcomes and reduce cost. One alternative is wound morphometry using digital wound images to evaluate wound response to treatment in realtime. To determine whether wound area measurements taken during the first 3 weeks of hyperbaric oxygen treatment predict eventual treatment response and how demographic and disease factors impact hyperbaric oxygen treatment response, a retrospective study using digital wound images, demographic data, and available clinical laboratory values was conducted. Participants included 29 wound care patients with nonhealing wounds of the lower extremities receiving treatment at a hyperbaric wound care facility. Conventional wound care (ie, debridement, dressing changes, and topical agents) plus hyperbaric oxygen treatment (100% oxygen breathing at 2.4 atmospheres absolute for 90 minutes) given once every weekday for up to 20 weeks was provided. Graphical analysis of normalized wound area over time revealed two groups: minimal responders (n=13) and robust responders (n=16). Minimal response was characterized by delayed onset of wound area reduction and virtual cessation of reduction by week 3. Robust response was continuous, sustained, and resulted in average wound area reduction of 80% by end of treatment, compared to 47% in minimally responsive patients. Age, blood glucose, and serum creatinine significantly affected the wound healing response to hyperbaric oxygen treatment (P<0.05). Digital images obtained during the first 3 weeks of treatment predicted if a patient is minimally responsive to hyperbaric oxygen treatment with 100% accuracy. Area measurements obtained in this manner can be used to identify patients minimally responsive to hyperbaric oxygen treatment, enabling rapid assessment of treatment response to make timely changes in therapy in order to optimize treatment outcomes.  相似文献   
109.
Nonenzymatic glycation of proteins, leading to chemical modification and cross-linking are of importance in the pathology of diabetic complications. We studied the effect alpha-lipoic acid (LA) on the content and characteristics of the protein collagen from skin of high-fructose fed rats. The rats were divided into 4 groups of 6 each. Two groups of rats were fed with a high fructose diet (60 g/100 g diet) and administered either LA (35 mg/kg b.w., i.p) (FRU+LA) or 0.2 ml vehicle (saline) (FRU) for 45 days. The other 2 groups were fed with control diet containing starch (60 g/100 g diet) and administered either saline (CON) or lipoic acid (CON+LA). The rats were maintained for 45 days and then sacrificed. Plasma glucose, insulin, fructosamine, protein glycation, and blood glycated hemoglobin (HbA1C) were measured. Collagen was isolated from skin and the physicochemical properties of collagen were studied. Fructose administration caused accumulation of collagen in skin. Extensive cross-linking was evidenced by enhanced glycation and AGE-linked fluorescence. Increased peroxidation and changes in physicochemical properties such as shrinkage temperature, aldehyde content, solubililty pattern, susceptibility to denaturing agents were observed in fructose-fed rats. SDS gel pattern of collagen from these rats showed elevated beta component of type I collagen. These changes were alleviated by the simultaneous administration of LA. Administration of LA to fructose-fed rats had a positive influence on both quantitative and qualitative properties of collagen. The results suggest a mechanism for the ability of LA to delay diabetic complications.  相似文献   
110.
Soluble N-ethylmaleimide-sensitive fusion protein (NSF) attachment protein receptor (SNARE) complexes composed of target (t-) SNAREs syntaxin and SNAP-25 and vesicle SNARE synaptobrevin play an essential role in neurosecretion. It is hypothesized that a transient intermediate complex between the t-SNAREs is formed during the assembly of the ternary complex. The existence of the t-SNARE binary complexes in vivo, however, has not been demonstrated. By using an affinity absorption scheme with preformed syntaxin-SNAP-25 complexes, we isolated antibodies capable of distinguishing free SNAP-25 from those associated with syntaxin. By semiquantitative immunohistochemistry, we estimated that, in cultured cerebellar neurons, the majority of SNAP-25 existed as complexes. Compared with the cultured neurons, PC12 cells expressed significantly less syntaxin, and we found that SNAP-25 was primarily in free forms. In contrast, a PC12 line that stably expressed a recombinant syntaxin showed a marked increase in SNAP-25 complexes. By using fluorescence resonance energy transfer (FRET) techniques, we observed FRET between cyan fluorescence protein-syntaxin and yellow fluorescence protein-SNAP-25 fusion proteins expressed in COS-7 and PC12 cells, suggesting a physiological interaction between syntaxin and SNAP-25. Our results demonstrate that, unlike what was previously hypothesized, syntaxin and SNAP-25 exist preferably as stable binary complexes in neurons. These findings offer novel insight into the mechanisms underlying the initiation and regulation of SNARE complex assembly.  相似文献   
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