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941.
942.
Keratinocyte activation following T-lymphocyte binding.   总被引:3,自引:0,他引:3  
T lymphocytes infiltrate the epidermis and follicular epithelium adhering to keratinocytes within hours following induction of cutaneous inflammation. To determine if the physical binding interaction between a T cell and keratinocyte induces transmission of activation pathways, CD3+ T cells (HUT 78) were allowed to directly bind to non-cytokine-treated cultured keratinocytes. When these T cells bound to keratinocytes, the keratinocytes were activated as evidenced by detection of tumor necrosis factor-alpha, interleukin-6, and intercellular adhesion molecule-1 mRNA. This induction was relatively mRNA specific, as several other mRNA were not found to be altered. This activation process appeared to be one-sided, as no change in HUT cell mRNA levels was detectable. The keratinocyte activation process was confined to cultures that had direct physical binding by HUT cells, because co-culturing the HUT cells immediately above the keratinocyte monolayer (but not in direct contact), resulted in no such mRNA alterations. This direct adhesion-mediated activation of keratinocytes by T lymphocytes may be important in the genesis of cutaneous inflammation by amplifying the original stimulus, as well as contributing to the trafficking pattern of inflammatory cells as they leave the general circulation and enter the skin.  相似文献   
943.
Serial electrocardiograms (ECGs) were recorded in 20 consecutive male patients admitted to the Infectious Diseases Hospital, Calcutta with generalised tetanus. Age of patients varied from 5 to 40 years (mean age 20.4 years). Ten patients died. ECGs were recorded daily for the first week after admission and later every 2nd or 3rd day. Altogether, 167 ECGs were analysed. Sinus tachycardia was present in 17 (85%) patients, prolonged QT interval in 12 (60%) patients, non-specific ST-T abnormalities in 12 (60%) patients and P wave changes in 10 (50%) patients. Other abnormalities recorded, included short PR interval, supraventricular tachycardia, intraventricular conduction delay, sinus bradycardia, 1 degree A-V block, abnormal axis deviation, right ventricular hypertrophy and sino-atrial Wenckebach phenomenon, although all of the findings cannot clearly be attributed to tetanus. Spatial QRS-T angle was calculated in 18 of these patients to determine any possible change in this parameter of prognostic significance. Two out of 9 who survived had abnormally wide (greater than or equal to 55 degrees) spatial QRS-T angle on admission; the angle narrowed with recovery. In the non-survivor group, 4 patients had abnormally wide QRS-T angles on admission; further widening was noted in patients on whom follow-up tracings were available. The difference in spatial QRS-T angle between the survivor and the non-survivor groups was statistically significant (p less than 0.05). Spatial QRS-T angle changes have not been reported in tetanus before. Although non-specific, serial study in individual cases would be useful in assessing prognosis.  相似文献   
944.
945.
Endoscopic management is the accepted form of treatment for posterior urethral valves (PUV) . The Nd:YAG laser has been in clinical use for many decades, but has been used only sporadically for ablating PUV. In this study, PUV were diagnosed by micturating cystourethrogram (MCU). In the 9-month period beginning March 1997, 23 boys 3 months to 9 years of age underwent endoscopic Nd:YAG laser surgery for PUV using a 600 quartz bare fibre through the catheter channel of an 8.5 F cystoscope. The laser power and total energy delivered ranged from 20 to 50 W and 50–1085 J, respectively. Type I PUV were present in 20 boys; 1 had type III, and in 1 boy each there were residual valves and a urethral stricture from a previous electrocautery ablation. All operations were done with the patient under general anaesthesia supplemented by caudal morphine. Routine postoperative cystoscopy was done in the first 5 cases only. All patients had a good stream of urine without bleeding or any other complication after valve ablation. Mucosal tags seen on follow-up cystoscopy in 5 patients were fulgurated by laser. In 4 other patients recystoscopy was required for deterioration of the urinary stream and persistent posterior urethral dilatation on MCU; residual valves were refulgurated by laser. An indwelling catheter was left in only 4 patients, 2 of whom were primarily operated and 2 following refulguration. All except the first 2 were treated as out-patients. Application of the Nd:YAG laser has added a new dimension for treating PUV. The initial experience has been very encouraging: the destruction of valves is precise, there are no complications, and it can be practised on a day-care basis without indwelling catheterisation. The bare fibre can be used repeatedly, thus reducing the cost of treatment. Accepted: 26 April 1999  相似文献   
946.
947.
Picobirnaviruses (PBVs) with bisegmented small RNA genome profile (1.75 and 1.55kbp for segment 1 and 2, respectively) were detected from 1999 to 2003 in faecal specimens of acute watery diarrhoea cases, largely children (n=20) and an adult in Kolkata, India. Varying degrees of dehydration necessitated their visit to hospital for further treatment and management of acute watery diarrhoea. PBV was associated with rotavirus (n=3) or astrovirus (n=3) and with both in one case. No co-infection with norovirus, sapovirus or adenovirus was detected in the picobirnavirus positive cases. No co-infection with parasites (Cryptosporidium spp., Giardia spp., Entamoeba spp., helminths) or bacteria (Vibrio spp., Shigella spp., Escherichia coli) was detected among the picobirnavirus positive cases. There was a single instance of co-infection with Salmonella spp. (n=1). PBVs not associated with serious diarrhoea illness and showing large genome profile (2.3-2.6 and 1.5-1.9kbp for segment 1 and 2, respectively) have earlier been reported in adult individuals and recently among children from a slum community in Kolkata, India. The short genome profile PBVs associated with acute watery diarrhoea may be another emerging diarrhoeagenic virus in Kolkata, India. Molecular characterization using reported primers PicoB25-PicoB43 for Genogroup I and PicoB23-PicoB24 for Genogroup II in RT-PCR showed the presence of Genogroup I PBVs (n=6) and Genogroup II PBVs (n=5), while some could not be amplified (n=3) with these primers. Sequence analysis of Genogroup I amplicons indicated remarkable sequence heterogeneity. After more than a decade, four PBV positives of Genogroup II were detected during this study. Phylogenetic analysis showed varying degree of genetic diversity amongst PBV strains from Kolkata and other countries.  相似文献   
948.
Methotrexate and dactinomycin are efficient drugs in the treatment of patients with low-risk gestational trophoblastic neoplasia (LRGTN). To compare the effectiveness of these two drugs in LRGTN, 46 patients were randomised to receive weekly intramuscular methotrexate at 30 mg/m(2) (n = 28) or intravenous dactinomycin at 1.25 mg/m(2) every 2 weeks (n = 18). Fourteen patients (50%) in the methotrexate group and 16 patients (89%) in the dactinomycin group achieved complete response. Greater patient convenience and a lower number of required visits make dactinomycin superior to other alternatives.  相似文献   
949.
Objective : To evaluate the incidence, types and the effect on outcome of associated anomalies in neonates with anorectal malformations (ARM).Methods : This retrospective study was carried out on all neonates with ARM admitted to the neonatal surgical intensive care unit (NSICU) from 1998 through 2003.Results : Of the 754 neonates admitted to the NSICU during the study period of 6 years, there were 124 (16.4%) neonates with anorectal malformations. Of these 110 were included in the study. 73 % were male and 27% female. 86% of these were high ARM (HARM) while only 14% were low ARM (LARM). Associated anomalies were seen in 68% of patients. The incidence was 72% for HARM and 50% for LARM. The major associated anomalies consisted of esophageal (13%), gastrointestinal (GIT) (11%), genitourinary (GUT) (32%), skeletal (26%), cardiac (33%) and miscellaneous 26%. The overall survival rate was 84% (82% for HARM and 94% for LARM). The survival among those with associated esophageal anomalies was 43%, GIT 67%, GUT 80%, cardiac 61%, skeletal 76% and miscellaneous 79% respectively. This difference in survival was significant only for those with esophageal (p=0.004) and cardiac anomalies (p=0.0026). The survival rates among those with one, two or more than two organ systems involved with associated anomalies were 88%, 82% and 58% respectively. This difference was significant only for more than two organ systems involvement (p=0.003).Conclusion : Associated anomalies are common in neonates with ARM, the incidence being similar for HARM and LARM. The survival depends upon the number and severity of associated anomalies both in patients with LARM and HARM. Neonates with more number of organ systems involved have a poorer survival specially when associated with esophageal and cardiac anomalies. All neonates with ARM merit a meticulous search for associated anomalies so that the management can be tailored for each baby.  相似文献   
950.
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