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11.
Renu Nandakumar Raksha Mirchandani Ashraf Fouad 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2007,103(3):429-432
BACKGROUND/OBJECTIVE: Recent polymerase chain reaction (PCR)-based studies have shown significant variability in the prevalence of Enterococcus faecalis cases with nonhealing endodontic infections. This variability may be, at least in part, due to the differences in sensitivities of the primers used. The purpose of this study was to compare the sensitivity of 3 sets of PCR primers which have been reported in the endodontic literature. METHODS: The 3 primers sets used were: group 1) tuf gene-based primers with genus-level specificity; and groups 2 and 3) 16S rDNA-based primers that were E. faecalis specific. Three strains of E. faecalis at concentrations of 10(2)-10(8) cells/mL were included in this study. RESULTS: The PCR amplification of E. faecalis strains with the 3 primer pairs showed that group 1 primers consistently had the highest sensitivity, followed by group 2 and group 3 (P<.0001). CONCLUSION: A tuf-based PCR identification assay followed by direct sequencing would yield accurate and consistent prevalence rates of E. faecalis in endodontic infections. 相似文献
12.
Andreas Granetzny Ashraf Hatem Alaa Shalaby Ahmad Boseila 《European journal of cardio-thoracic surgery》2005,27(3):361-366
OBJECTIVE: In a prospective study, the effect of thymectomy on the pulmonary status of 50 consecutive patients with myasthenia gravis was evaluated over a time range of 4 years in the Chest and Chest surgery departments in the Cairo University Clinics and Thoracic Surgery Department of the Evangelisches Krankenhaus Duisburg-Nord. METHODS: The patients were divided into two groups: Group I included 26 patients who underwent thymectomy through median sternotomy. The mean age of the patients in this group was 24.8+/-10.5 (5-41) years. They were 19 females and seven males. Thirteen of the patients were in Myasthenia Gravis Foundation of America (MGFA) class IIa, and 12 were in class IIb, and one was in class IIIa. Group II included 24 patients who underwent thymectomy through manubriotomy. The mean age of the patients in this group was 25.2+/-9.2 (12-41) years. They were 13 females and 11 males. Eight of the patients were in MGFA class 2a, 14 were in class IIb, and two were in class IIIa. RESULTS: When compared to group I in which postoperative ventilation was required in 15.4% of patients, postoperative ventilation was not necessary in patients of group II with a statistically significant difference (P=0.04). The mean duration of stay in the intensive care unit was 111.4h in group II, and 169.7h in group I (P=0.03). The peak inspiratory flow rate and the forced vital capacity were also statistically significantly better in group II. There was no mortality in both groups, and the morbidity was higher in the median sternotomy group. CONCLUSION: Thymectomy through a manubriotomy, which allows extensive removal of ectopic thymic tissue in addition to the thymus through a less invasive approach than a full median sternotomy, is associated with a significantly smoother postoperative course and less pulmonary complications, when compared with thymectomy through a full median sternotomy. 相似文献
13.
D Mahalanabis H Ashraf MM Rahman GJ Fuchs 《Acta paediatrica (Oslo, Norway : 1992)》1998,87(11):1113-1115
One-hundred and six male children aged 6-23 months with a history of acute watery diarrhoea of less than 72 h duration were randomized to receive either folic acid in a dose of 5 mg at 8-h intervals or placebo for 5 d. There were 54 children in the folic acid group and 52 in the placebo group. The admission characteristics were comparable between the two groups. No significant differences were observed in the intake of oral rehydration solution or stool output between the groups. The mean ± SD of total stool output (g kg−1 ) was 532 ± 476 vs 479 ± 354 and the duration (h) of diarrhoea was 108 ± 68 vs 103 ± 53 in the folic acid vs placebo group, respectively. The findings, therefore, should have a positive influence on preventing the inappropriate use of folic acid in acute diarrhoea. 相似文献
14.
A plant and fungal toxin, 3-NPA, acts as an inhibitor of mitochondrial function via irreversible inactivation of the mitochondrial inner membrane enzyme, succinate dehydrogenase (SDH). Inhibition of SDH disturbs electron transport and leads to cellular energy deficits and neuronal injury. We have shown that pretreatment with l-carnitine, while not significantly attenuating SDH inhibition, prevented hypothermia and oxidative stress-associated increased activity of free radical-scavenging enzymes. Here, a neurohistological method was applied to examine the effect of carnitine pretreatment against 3-NPA-induced neurotoxicity. Twenty adult male Sprague-Dawley rats were randomly divided into two groups (n = 10/group). Rats in the first group were injected twice with 3-NPA at 30 mg/kg s.c., 2 days apart, and the second group of animals received l-carnitine pretreatment at 100 mg/kg 30-40 min before 3-NPA administration. Rats in both groups were perfused 7 days later and their brains harvested. Degenerating neurons were identified and localized via the fluorescent marker Fluoro-Jade B. In the three animals that survived 3-NPA dosing, one exhibited no pathology, one exhibited moderate unilateral damage to the striatum, and the third exhibited extensive bilateral neuronal degeneration in multiple forebrain regions. In the seven surviving animals that received l-carnitine prior to 3-NPA insult, six exhibited no lesions, while one exhibited a modest unilateral lesion in the striatum. It appears that l-carnitine is protective against 3-NPA-induced toxicity, as reflected by both reduced mortality and significantly reduced neuronal degeneration. 相似文献
15.
Pigtail catheter for the treatment of ascites associated with ovarian hyperstimulation syndrome 总被引:1,自引:0,他引:1
Abuzeid MI Nassar Z Massaad Z Weiss M Ashraf M Fakih M 《Human reproduction (Oxford, England)》2003,18(2):370-373
BACKGROUND: Severe ovarian hyperstimulation syndrome (OHSS) is potentially dangerous. The study aim was to evaluate the efficacy and safety of percutaneous pigtail catheter drainage for the management of ascites complicating severe OHSS. METHODS: This was a prospective trial conducted at a private IVF centre and a tertiary teaching medical centre. A total of 26 patients with severe OHSS was recruited. Patients were divided into two groups. Patients in group 1 (n = 13) were hospitalized, while patients in group 2 (n = 13) were managed on an outpatient basis. A pigtail catheter was inserted under transabdominal ultrasound guidance and kept in place until drainage ceased. The main outcome measures were resolution of OHSS as determined by symptomatology and laboratory values, time to removal of catheter, patient tolerance of the procedure and complication rate. RESULTS: The catheter was successfully placed in all patients following one attempt and was kept in place for a mean +/- SD of 12.9 +/- 4.3 days (range 7-24). Average amount of fluid drained was 11.2 +/- 4.3 l (range: 3.35-18.5). An improvement of symptoms and signs was noted 24-48 h after catheter placement in all patients in both groups. Procedure was well tolerated and no complications reported. CONCLUSIONS: Percutaneous placement of a pigtail catheter is a safe and effective treatment modality for severe OHSS. It may represent an attractive alternative to multiple vaginal or abdominal paracentesis. 相似文献
16.
Ashraf S. Yousif Larance Ronsard Pankaj Shah Tatsushi Omatsu Maya Sangesland Thalia Bracamonte Moreno Evan C. Lam Vladimir D. Vrbanac Alejandro B. Balazs Hans-Christian Reinecker Daniel Lingwood 《Immunity》2021,54(2):235-246.e5
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17.
Maximal dynamic expiratory pressures are higher when forced expiration is preceded by a fast inspiration to total lung capacity
(TLC) than when preceded by a slow inspiration and a few seconds pause at TLC. We hypothesized that these pressure differences
are due to the stretch-shorten cycle (SSC), which refers to enhancement of muscle force when a concentric muscle contraction
is immediately preceded by an eccentric contraction. Seven volunteers [36 (2) years; mean (SEM)] performed maximal forced
expirations against minimal resistance with fast (F) or slow (S) maneuvers. F maneuvers consisted of a fast inspiration to
TLC followed immediately by a fast expiration, whereas S consisted of a slow inspiration to TLC and a 4- to 5-s pause at TLC
prior to forced expiration. We measured esophageal pressure (P
es), peak expiratory flow rate (PEFR), and the EMG activity of the transversus abdominis (Tr) by means of intramuscular fine-wire
electrodes. The subjects performed several runs of each maneuver in a random order, and runs with the greatest expiratory
P
es were analyzed. In comparison with S, F yielded greater P
es [182 (15) versus 167 (15) cmH2O; P=0.003)] but similar PEFR [9.8 (0.7) versus 9.6 (0.7) l/s, P>0.05] and EMG activity of the Tr during forced expiration [221 (31) versus 208 (34) a.u., P>0.05]. Further analysis revealed significant EMG activity of Tr during end-inspiration (eccentric contraction) with F maneuvers
only [73 (22) versus 32 (17) a.u., P<0.05]. We conclude that the ability of expiratory muscles to generate greater P
es with F maneuvers is related to the sequence of an eccentric contraction, which is followed immediately by concentric contraction
in a manner analogous to SSC described in skeletal muscles.
Electronic Publication 相似文献
18.
Anupama Kohli MD Stephen P. Baker MCS MPH Nilima A. Patwardhan MD Ashraf Khan MD MRCPATH 《Endocrine pathology》1998,9(2):117-123
Previous studies have established that thyroid follicular neoplasms of higher malignant potential show a high p53 and low
bc1-2 expression. This however has not been well studied in Oncocytic (Hürthle cell) neoplasms, the management of which remains
controversial. We therefore studied the expression of p53 and bc1-2 in 18 Hürthle cell adenomas (HCA) and 8 Hürthle cell carcinomas
(HCC) and compared them with their benign and malignant counterparts, respectively, including 16 follicular adenomas (FA)
and 68 papillary carcinomas (PC). All 16 FA were bc1-2 positive, 4 were 2+, and 12 were 3+. On the other hand, 14/18 (78%)
HCA showed bc1-2 expression, 5 were 1+, 6 were 2+, and only 3 were 3_. Similarly, HCC showed a weaker bc1-2 staining pattern
compared to PC. Only 1 FA showed grade 1, p53 staining, the remaining 15 were negative, and 15/18 HCA showed p53 expression
of varying grades. This difference in p53 staining was statistically significant (p=0.005). A significant p53 overexpression was also seen in HCC compared to PC (p=0.005). In conclusion, there appears to be an inverse relationship between p53 and bc1-2 expression in thyroid follicular
neoplasms. A higher expression of p53 and lower levels bc1-2 in Hürthle cell neoplasms may have biological and clinical implications.
This may support a more aggressive surgical treatment for HCA compared to FA. 相似文献
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