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1.
An immunofluorescent (IF) method that detects Burkholderia pseudomallei in clinical specimens within 10 min was devised. The results of this rapid method and those of an existing IF method were prospectively compared with the culture results for 776 specimens from patients with suspected melioidosis. The sensitivities of both IF tests were 66%, and the specificities were 99.5 and 99.4%, respectively.  相似文献   
2.
Epidemiological studies have indirectly linked compounds ofchromium, nickel and arsenic to human carcinogenesis. However,there is no evidence that metal compounds can transform humancells to the tumorigenic phenotype in culture. We show herethat exposure to 36 µM NiS04 for 48–96 h resultsin transformation of an immortal, non-tumorigenic, osteoblast-likecell line, HOS TE85, to the tumorigenic phenotype. Continuouspassaging following treatment leads to the formation of a fewdense foci. The cells isolated and expanded from the foci aremorphologically transformed, and form anchorage-independentcolonies of the size and abundance comparable to that formedby Kirsten murine sarcoma virus transformed HOS TE85 cells.The transformed cells from tumors in nude mice, have enhancedlevels of plasminogen activators and have lost the ability toform model bone matrix on extended culture in the presence ofascorbic acid and ß-glycerophosphate. A number ofcell lines have been established from nude mouse tumors. Cytogeneticanalysis reveals 16 marker chromosomes and an aberrant chromosome16. This is the first report of the transformation of a humancell line to tumorigenic phenotype by a metal carcinogen.  相似文献   
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4.
Viral hepatitis represents a major global health problem with 170 million Hepatitis C Virus (HCV) carriers worldwide, and 12–13 million HCV carriers in India. HCV genotypes are of clinical significance in indicating drug responsiveness and prognosis of the patient. The HCV genotypes are of epidemiologic significance as well, as they are indicative of transmission route of infection and have not been extensively studied in the Indian context. In the current study, HCV genotyping was examined in 2118 patients from different geographic regions of India. HCV was detected by PCR amplification of 5′ UTR and core-envelope1 regions, followed by genotyping using nucleotide sequencing and analysis with NCBI tool (http://www.ncbi.nlm.nih.gov/projects/genotyping/formpage.cgi). HCV genotype distribution in the 2118 Indian patients demonstrated prevalence of HCV3 (3a/3b primarily) in 62% and HCV1 (1a/1b primarily) in 31% patients. The predominance of HCV3 was significant in northern (p = 0.01) and eastern (p = 0.008) regions of India. HCV types 2, 4, 5, and 6 were detected in 0.05–4.5% of the patient group. Thus, our studies demonstrate HCV genotype prevalence in the cohort group in different regions of India.  相似文献   
5.
Background: Controversy exists as to the risk for postoperative apnea in former preterm infants. The conclusions of published studies are limited by the small number of patients.

Methods: The original data from eight prospective studies were subject to a combined analysis. Only patients having inguinal herniorrhaphy under general anesthesia were included; patients receiving caffeine, regional anesthesia, or undergoing other surgical procedures were excluded. A uniform definition for apnea was used for all patients. Eleven risk factors were examined: gestational age, postconceptual age, birth weight, history of respiratory distress syndrome, bronchopulmonary dysplasia, neonatal apnea, necrotizing enterocolitis, ongoing apnea, anemia, and use of opioids or nondepolarizing muscle relaxants.

Results: Two hundred fifty-five of 384 patients from eight studies at four institutions fulfilled study criteria. There was significant variation in apnea rates and the location of apnea (recovery room and postrecovery room) between institutions (P < 0.001). There was considerable variation in the duration and type of monitoring, definitions of apnea, and availability of historical information. The incidence of detected apnea was greater when continuous recording devices were used compared to standard impedance pneumography with alarms or nursing observations. Despite these limitations, it was determined that: (1) apnea was strongly and inversely related to both gestational age (P = 0.0005) and postconceptual age (P < 0.0001); (2) an associated risk factor was continuing apnea at home; (3) small-for-gestational-age infants seemed to be somewhat protected from apnea compared to appropriate- and large-for-gestational-age infants; (4) anemia was a significant risk factor, particularly for patients > 43 weeks' postconceptual age; (5) a relationship to apnea with history of necrotizing enterocolitis, neonatal apnea, respiratory distress syndrome, bronchopulmonary dysplasia, or operative use of opioids and/or muscle relaxants could not be demonstrated.  相似文献   

6.
Anaesthetic and sedation techniques, complications and outcomes were reviewed in 176 children undergoing 184 interventional cardiologic procedures. Techniques included sedation only, and ketamine, inhalational or narcotic anaesthesia. Ketamine infusion was the technique most frequently used. Ketamine was associated with a higher incidence of respiratory complications (P < 0.05) than the other techniques. The higher incidence of hypercarbia (15.6 per cent), which did not affect outcome, may be attributable to the use of supplemental sedatives. The incidence of upper airway obstruction (7.8 per cent) was similar to that of previous studies. Vascular compromise resulted from the procedure in 33 patients, necessitating surgical correction in 16. Cardiac perforation occurred in four cases, causing one death. Pulmonary valve stenosis was most amenable to balloon dilatation and aortic valve stenosis least amenable. Ketamine was the anaesthetic agent preferred by cardiologists for use in the catheterisation suite when general anaesthesia was required. Vigilant monitoring by anaesthetic staff is necessary during the procedure, and avoidance of concomitant narcotics is recommended if a ketamine technique with spontaneous ventilation is used. Les techniques anesthésiques et de sédation ainsi que les complications et les issues ont été revues chez 176 enfants subissant 184 procedures cardiaques. Les techniques ont inctu soil la sédation seulement, soit l’anesthésie à la kétamine, aux agents d’inhalation ou aux narcotiques. La perfusion de kétamine était la technique la plus fréquemment utilisée. La ketamine était associée à une plus grande incidence de complication respiratoire (P < 0.05) comparativement aux autres techniques. La plus grande incidence d’hypercarbie (15.6 pour cent), n’ayant pas affecté l’issue, pourrait être attribuée à l’utilisation additionnelle de sédatifs. L’incidence d’obstruction des voies aériennes supérieures (7.8 pour cent) était similaire aux études préalables. Un problème vasculaire suite à la procédure fut observé chez 33 patients dont 16 ont requis une correction chirurgicale. Une perforation cardiaque est survenue dans quatre cas provoquant le décès d’un seul patient. La sténose de la valve pulmonaire était la procédure la plus susceptible d’être dilatée et la sténose de la valve aortique la moins susceptible. La kétamine était l’agent anesthésique préféré par les cardiologistes lors des cathétérisations quand une anesthésie générate était requise. Une surveillance vigilante par une équipe anesthésique fut nécessaire durant la procedure. Il faut aussi éviter l’administration de narcotiques si la kétamine est administrée en respiration spontanée.
Presented in part at the Canadian Anaesthetists’ Society annual meeting in Halifax, June 1988.  相似文献   
7.
Development of pancreatic hepatocytes in adult rats maintained on copper deficient diet containing 0.6% trien (CuDT) has been reported recently. To elucidate the histogenesis of hepatocytes a sequential study was undertaken using morphologic, histochemical, immunochemical, in situ hybridization, and Northern blot analysis. Male F-344 rats weighing 80 to 90 g were fed CuDT for 8 weeks and returned to normal rat chow. Beginning from 4 weeks of copper depletion, there was a progressive loss of acinar cells and by 8 weeks more than 90% of the acinar tissue was lost. During this period, there was an increase in the number of adipocytes in the interstitium, and in the number of interstitial and ductular cells. Morphologic observations were confirmed by immunoblot and Northern blot analysis, in which the amount of pancreatic proteins and their mRNAs decreased between 5 and 8 weeks. During this period, a progressive increase in the level of albumin mRNA was observed. In situ hybridization, performed at 7 weeks of copper deficiency, showed localization of albumin mRNA over interstitial and ductular cells. Pancreatic hepatocytes were identified immediately after the rats were returned to a normal diet and gradually increased in number. The hepatocytes occupied almost 60% of the pancreatic volume by 8 weeks. During the early recovery phase, hepatocytes were identified in ductules as well as in the interstitium. Based on these studies, it is concluded that both the ductular cells and interstitial cells, which resemble oval cells of liver, are capable of transforming into pancreatic hepatocytes and these cells may be considered stem-cell equivalent.  相似文献   
8.
Recently, rotavirus antigenemia and viremia have been identified in patients with acute gastroenteritis. This study examined rotavirus viremia in children hospitalized for acute gastroenteritis in order to establish its association with fecal shedding of rotavirus, infecting genotypes and antibody marker of acute infection. Thirty‐one pairs of stool–serum specimens were collected from November 2004 to February 2005 together with clinical information. All paired specimens were screened for rotavirus RNA by RT‐PCR using the VP6 gene primers. All stool and serum specimens were tested for rotavirus antigen and anti‐rotavirus IgM respectively by ELISA. Sixteen of 31 stool–serum pairs showed the presence of rotavirus RNA. Nine stool and two serum specimens were positive only by RT‐PCR. The total positivity in rotavirus RNA was significantly higher in both stools (80.6%) and sera (58.1%) than that of stool antigen (38.7%) and anti‐rotavirus IgM (25.8%) (P < 0.01). All PCR positive paired specimens were typed for the VP7 (G) and VP4 (P) genes. Five of sixteen pairs could be typed for both genes. Three of the five pairs showed concordance (G2P[4]/G2P[4]) while two showed discordance (G12P[8]/G2P[4], G8P[4]/G2P[4]) in the genotypes detected in stool and serum specimens respectively. The study documents a high frequency of rotavirus viremia in patients with acute diarrhea. The discordance of rotavirus strains at the genotypic level in the serum and stool of individual patients with diarrhea suggests the susceptibility of extra‐intestinal sites for rotavirus infection and the possibility of differential dissemination of rotavirus strains from the intestine. J. Med. Virol. 80:2169–2176, 2008. © 2008 Wiley‐Liss, Inc.  相似文献   
9.
Histopathology reports are important quality assurance tools and evaluation of pathological diagnoses described in them is an integral part of total quality control and quality improvement program. We describe a program based on slide circulation which was aimed at both continuing education to upgrade knowledge and proficiency testing of histopathologists. The performance of the participating pathologists was analyzed and the degree of agreement was also studied. The results showed improvement indicated by rising level of performance in 35.3% of consistent participants and increasing trend in the average score. The degree of agreement was comparatively low (65.29%). The practicability of this program and its acceptability as an EQAS was also investigated.  相似文献   
10.
Human melioidosis is associated with a high rate of recurrent disease, despite adequate antimicrobial treatment. Here, we define the rate of relapse versus the rate of reinfection in 116 patients with 123 episodes of recurrent melioidosis who were treated at Sappasithiprasong Hospital in Northeast Thailand between 1986 and 2005. Pulsed-field gel electrophoresis was performed on all isolates; isolates from primary and recurrent disease for a given patient different by one or more bands were examined by a sequence-based approach based on multilocus sequence typing. Overall, 92 episodes (75%) of recurrent disease were caused by the same strain (relapse) and 31 episodes (25%) were due to infection with a new strain (reinfection). The interval to recurrence differed between patients with relapse and reinfection; those with relapses had a median time to relapse of 228 days (range, 15 to 3,757 days; interquartile range [IQR], 99.5 to 608 days), while those with reinfection had a median time to reinfection of 823 days (range, 17 to 2,931 days; IQR, 453 to 1,211 days) (P = 0.0001). A total of 64 episodes (52%) occurred within 12 months of the primary infection. Relapse was responsible for 57 of 64 (89%) episodes of recurrent infection within the first year after primary disease, whereas relapse was responsible for 35 of 59 (59%) episodes after 1 year (P < 0.0001). Our data indicate that in this setting of endemicity, reinfection is responsible for one-quarter of recurrent cases. This finding has important implications for the clinical management of melioidosis patients and for antibiotic treatment studies that use recurrent disease as a marker for treatment failure.  相似文献   
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