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931.
Immunomodulatory activity of Seabuckthorn (SBT) leaf extract was evaluated in adjuvant induced arthritis (AIA) rat model. Inflammation was induced by injecting Complete Freund's Adjuvant (CFA) in the right hind paw of rats. SBT extract was administered intraperitoneally to treat the inflammation. The extent of inflammation and treatment response was evaluated by clinical analysis, scintigraphic visualization using technitium-99m-glutathione (Tc99m-GSH) and lymphocyte proliferation. Serial evaluation was carried out on days 1, 7, 14, 21 and 28 after creation of inflammation. The Tc99m-GSH uptake in the inflamed leg was compared with the normal contralateral leg of the same animal. The measurements were done by obtaining scintigraphic images using gamma camera and an online computer. Both qualitative and quantitative evaluation of radiotracer accumulation was considered to evaluate the anti-inflammatory response. The lymphocyte proliferation study revealed cellular immunosuppression during the early phase of the disease. Administration of SBT extract on the same day or 5 days prior to inflammatory insult into the joint, significantly reduced the inflammation as compared to the untreated animals in a dose dependent manner. These observations suggest that the SBT leaf extract has a significant anti-inflammatory activity and has the potential for the treatment of arthritis.  相似文献   
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935.
The combination of sulfadoxine-pyrimethamine (SP) is used as a second line of therapy for the treatment of uncomplicated chloroquine-resistant Plasmodium falciparum malaria. Resistance to SP arises due to certain point mutations in the genes for the dihydrofolate reductase (DHFR) and dihydropteroate synthetase (DHPS) enzymes of the parasite. We have analyzed these mutations in 312 field isolates of P. falciparum collected from different parts of India to assess the effects of drug pressure. The rate of mutation in the gene for DHFR was found to be higher than that in the gene for DHPS, although the latter had mutations in more alleles. There was a temporal rise in the number of isolates with double dhfr mutations and single dhps mutations, resulting in an increased total number of mutations in the loci for DHFR and DHPS combined over a 5-year period. During these 5 years, the number of isolates with drug-sensitive genotypes decreased and the number of isolates with drug-resistant genotypes (double DHFR mutations and a single DHPS mutation) increased significantly. The number of isolates with the triple mutations in each of the genes for the two enzymes (for a total of six mutations), however, remained very low, coinciding with the very low rate of SP treatment failure in the country. There was a regional bias in the mutation rate, as isolates from the northeastern region (the state of Assam) showed higher rates of mutation and more complex genotypes than isolates from the other regions. It was concluded that even though SP is prescribed as a second line of treatment in India, the mutations associated with SP resistance continue to be progressively increasing.  相似文献   
936.
Regular treatment of large vestibular schwannomas (VS) is surgical resection of the tumor with attempt of facial nerve preservation. In a very reduced number of tumors, microsurgery is not warranted mainly because of controlateral deafness or the risk of life-threatening open surgery. The purpose of this study was to analyze the results of Gamma Knife radiosurgery delivered for large VS. Between July 1992 and January 2002, we treated 50 patients harboring a large VS defined as a Koos grade IV tumor. Data and follow-up were available for 45 tumors involving 44 patients, including 12 neurofibromatosis type 2. Mean age at the time of treatment was 43,5 (range: 14-84), mean diameter of the tumor in the CPA was 18mm (range: 12-30) and the mean Volume was 4301 mm3 (range: 1340-11405). Gamma knife treatment was undertaken using on average 13.4 isocenters (range: 4-48) and 10.2 Gy at the tumor margin (range: 8-14). Median follow-up was 45.5 Months (from 24 to 108 Months). Tumor control was 69% (interval confidence: 52-83%) and 3 patients had to be operated because of continuous tumor growth. Statistical analysis showed that tumor Volume was correlated to Gamma Knife failure in a uni-and multivariate model (p=0.027). No brain stem complication was observed. No facial nerve deterioration was found and hearing preservation could be obtained at a useful level in 12 out of 20 patients (60%). These results suggest that in a highly selected subgroup of patients with large VS, radiosurgery can be an interesting alternative to open surgery, particularly if hearing preservation is required. Information should be given to the patients that the risk of failure is greater than for small and medium sized VS.  相似文献   
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938.
OBJECTIVE: To estimate the differences in immediate maternal and neonatal effects of forceps and vacuum-assisted deliveries. METHODS: We conducted a medical record review of all forceps and vacuum-assisted deliveries that occurred from January 1, 1998, to August 30, 1999, at Winthrop-University Hospital. Maternal demographics and delivery characteristics were recorded. Maternal outcomes, such as use of episiotomy and presence of lacerations, were studied. Neonatal outcomes evaluated were Apgar scores, neonatal intensive care unit admissions, cephalohematomas, instrument marks and bruising, and caput and molding. RESULTS: Of 508 operative vaginal deliveries, 200 were forceps and 308 were vacuum assisted. Forceps were used more often than vacuum for prolonged second stage of labor (P =.001). There was a higher rate of epidural (P =.02) and pudendal (P <.001) anesthesia, episiotomies (P =.01), maternal third- and fourth-degree perineal (P <.001) and vaginal lacerations (P =.004) with the use of forceps, whereas periurethral lacerations were more common in vacuum-assisted (P =.026) deliveries. More instrument marks and bruising (P <.001) were found in the neonates delivered by forceps, whereas there was a greater incidence of cephalohematomas (P =.03) and caput and molding (P <.001) in the neonates delivered with vacuum. Multivariable logistic regression analysis showed that forceps use was associated with an increase in major perineal and vaginal tears (odds ratio [OR] 1.85; 95% confidence interval [CI] 1.27, 2.69; P =.001), an increase in instrument marks and bruising (OR 4.63; 95% CI 2.90, 7.41; P <.001) and a decrease in cephalohematomas (OR 0.49; 95% CI 0.29, 0.83; P =.007) compared with the vacuum. CONCLUSIONS: Maternal injuries are more common with the use of forceps. Neonates delivered with forceps have more facial injuries, whereas neonates delivered with vacuum have more cephalohematomas. LEVEL OF EVIDENCE: II-3  相似文献   
939.
Epstein–Barr virus (EBV)‐associated post‐transplant lymphoproliferative disease (PTLD) in pediatric liver transplant recipients is associated with a high mortality (up to 60%) and the younger age groups, who are predominantly EBV‐naïve, are at highest risk for development of this disease. The aim of this study is to assess, in this high‐risk group, patient outcome and graft loss to rejection when complete withdrawal of immunosuppressive agents (IMS) is instituted as the mainstay of treatment in addition to the use of standard therapy. A retrospective analysis of 335 pediatric patients whose liver transplants were performed by our team between September 1988 and September 2002, was carried out through review of computer records, database and patient charts. Fifty patients developed either EBV or PTLD; 80% were ≤2 yr of age. Of these 50 patients, 19 had a positive tissue diagnosis for PTLD and 31 were diagnosed with EBV infection, 14 of whom had positive tissue for EBV. Fifty‐eight percent of patients who developed PTLD and 51.6% of patients with EBV received antibody for induction or treatment of rejection prior to onset of disease. Forty‐six patients (92%) received post‐transplant antiviral prophylaxis with ganciclovir or acyclovir. Antiviral treatment included ganciclovir in 76%, acyclovir in 20% and Cytogam (in addition to one of the former agents) in 44%. In those with PTLD, treatment included chemotherapy (n = 1), Rituximab (n = 2), and ocular radiation (n = 1). IMS was stopped in all patients with PTLD and in 19 with EBV infection and was held as long as there was no allograft rejection. Eight patients have remained off IMS for a mean of 1535.5 ± 623 days. Of the 21 patients who were restarted on IMS for acute rejection, 18 responded to steroids and/or reinstitution of low‐dose calcineurin inhibitors. The mean time to rejection while off IMS in this group was 107.43 ± 140 days (range: 7–476). Two patients were re‐transplanted for chronic rejection; one had chronic rejection that existed prior to discontinuing IMS. The mortality rate in our series was 31.6% in those with PTLD and 6% in those with EBV disease. The cause of death was related to PTLD or sepsis in all cases; no deaths were due to graft loss from acute or chronic rejection. PTLD is associated with high mortality in the pediatric population. Based on this report, we advocate aggressive management of PTLD that is composed of early cessation of IMS, the use of antiviral therapy, and chemotherapy when indicated. Episodes of rejection that occur after stopping IMS can be successfully treated with standard therapy without graft loss to acute rejection.  相似文献   
940.
This study was performed to find out whether ultrasound is an important adjunct to clinical and laboratory profile in diagnosing dengue fever or dengue haemorrhagic fever and to further determine whether ultrasound is useful in predicting the severity of the disease. Ultrasound was performed on 128 patients (2-9 years) with clinical suspicion of dengue fever. Serological tests were performed to confirm the diagnosis. 40 patients were serologically negative for dengue fever and later excluded from the study. Of the remaining 88 serologically positive cases, 32 patients underwent ultrasound on second to third day, repeated on fifth to seventh day of fever and in 56 patients ultrasound was done only on fifth to seventh day of fever. Of the 32 patients who underwent the study on second to third day of fever, all showed gall bladder wall thickening and pericholecystic fluid, 21% had hepatomegaly, 6.25% had splenomegaly and right minimal pleural effusion. Follow-up ultrasound on fifth to seventh day revealed ascites in 53% left pleural effusion in 22% and pericardial effusion in 28%. Of the 56 patients who underwent the study on fifth to seventh day of fever for the first time all had gall bladder wall thickening, 21% had hepatomegaly, 7% had splenomegaly, 96% had ascites, 87.5% had right pleural effusion, 66% had left pleural effusion and 28.5% had pericardial fluid. To conclude, in an epidemic of dengue, ultrasound features of thickened gall bladder wall, pleural effusion and ascites should strongly favour the diagnosis of dengue fever.  相似文献   
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