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91.
A new pentacyclic triterpenoid, 3alpha-(3",4"-dihydroxy- trans-cinnamoyloxy)- D-friedoolean-14-en-28-oic acid ( 1) has been isolated along with two known compounds, rhamnocitrin ( 2) and isorhamnetin ( 3) from the aerial parts of Tamarix hispida Willd. Compound 1 was found to be a potent antioxidant. In addition, compounds 1 - 3 showed significant inhibitory activity against prolylendopeptidase (PEP).  相似文献   
92.
Hydrogels based on poly(acrylic acid) and gelatin crosslinked with N,N'-methylene bisacrylamide (0.5mol%) and glutaraldehyde (4%), respectively, forming an interpenetrating network were employed as matrices, for studying the loading and release of gentamicin sulphate. The release kinetics of gentamicin sulphate was evaluated in water (pH approximately 5.8), phosphate buffer (pH 7.4) and citrate buffer (pH 4) at 37+/-0.1 degrees C. The drug release in phosphate buffer was faster as compared to water or citrate buffer. Fitting the data of release studies in Peppas model indicated that the release of drug from full IPNs in phosphate buffer (pH 7.4), water (pH approximately 5.8) and citrate buffer (pH 4) were diffusion controlled. However, semi-IPNs showed both anomalous and Fickian diffusion mechanisms. With increasing gelatin percentage in the polymer, rate of drug release was faster and almost 85% of the loaded drug was released within 7 days in phosphate buffer (pH 7.4).  相似文献   
93.
94.
Background/Purpose: It is well realized that Anderson-Hyne’s pyeloplasty fails to improve the drainage pattern and renal functional parameters in a few cases of hydronephrosis because of pelviureteric junction (PUJ) obstruction. The purpose of this study is to delineate the lower extent of the abnormally innervated pelviureteric junction by S-100 immunohistochemistry, which requires surgical removal.Methods: Thirty pelviureteric junction (PUJ) specimens were analyzed by histology and by S-100 immunohistochemistry after serial sectioning of the resected ureter and compared with the variables age, calyceal separation, parenchymal thickness, differential renal function, glomerular filtration rate (GFR), and the measured constricted ureteral segment on gross examination.Results: No significant correlation was noted (P > .05) when the histology was analyzed to find any association with any of the variables studied. The length of the visible constricted segment ranged from 2 mm to 15 mm (mean, 5.37 mm). The abnormally innervated segment was much longer than the length of the visible constricted segment in 24 and of the same length in 5 specimens. However, in 1 case, the abnormal innervation segment was shorter than the macroscopic constriction by 3 mm. The maximum difference in length between the visible constriction and the lower limit of defective innervation was 8 mm.Conclusions: The abnormally innervated ureteral segment below the PUJ in hydronephrosis is longer than the visible constricted segment at the time of surgery, and the ureter should be excised at least 8 mm or more beyond the visible lower limit of the constricted segment in cases of Anderson-Hyne’s pyeloplasty.  相似文献   
95.
We report an unusual severe systemic reaction that occurred in a woman after a (99m)Tc-methylene diphosphonate bone scan and for which no alternative explanation could be found. The bone scintigram showed diffusely increased uptake in the liver and kidneys accompanied by reversible dysfunction of these organs and dermatologic manifestations. We speculate that an immune-mediated mechanism may have caused this unusual reaction.  相似文献   
96.
97.
Delphinium denudatum Wall. (Ranunculaceae) is a medicinal herb used for the treatment of epilepsy in the subcontinent. The present study reports the anticonvulsant activities in the maximal electroshock test (MEST) and subcutaneous pentylenetetrazole (PTZ), bicuculline (BIC), picrotoxin (PIC)-induced seizures of the FS-1 subfraction (FS-1) that was obtained by purification of an aqueous fraction isolated from the roots of D. denudatum. In CF 1 mice, FS-1 (600 mg/kg i.p.) exhibited very potent anticonvulsant activity that was comparable to the effects of the well-known antiepileptic drug phenytoin (20 mg/kg) in MEST and protected 100% animals from hind limb tonic extension phase of this model. FS-1 also suppressed PTZ-induced threshold seizure and the loss of the righting reflex with tonic fore and hind limb extension by 100%, similar to the antiepileptic drug valproic acid (350 mg/kg). BIC-induced seizures were suppressed in 80% of the animals. FS-1 exhibited weak anticonvulsant effect on PIC-induced seizures, however, it significantly reduced mortality and delayed the onset of seizures. FS-1 had no effect on strychnine (STN)-induced extensor seizures. The results demonstrate the broad and potent anticonvulsant activity of the compounds in FS-1 of D. denudatum.  相似文献   
98.
The present study was undertaken to evaluate the knowledge, attitude and practices about neonatal hypothermia among medical and paramedical staff dealing with newborn care. A total of 160 subjects were assessed (40 pediatric medicine residents, 40 obstetric residents, 40 private practitioners and 40 paramedical staff working in labor room and postnatal wards) A pre-tested structured questionnaire was used. Only 47.8% of the subjects defined neonatal hypothermia correctly. As many as 52.2% of the interviewees considered it to be an uncommon problem. Lethargy, refusal for feed and cold to touch were mentioned as common symptoms of neonatal hypothermia by 97.5%, 80% and 77.5% of the respondents respectively. Decreased body temperature, cyanosis, apnea and edema of feet were found as common signs. Only 18.6% of the interviewees had knowledge about correct method of recording the temperature in a newborn. The present study reveals the gross lacunae in the knowledge regarding various aspects of neonatal hypothermia among pediatric and obstetric residents and paramedical staff working in labor room and postnatal wards. To reduce the neonatal morbidity and mortality due to neonatal hypothermia, greater emphasis should be laid on this problem while designing curriculum for training of undergraduate and postgraduate doctors, paramedical staff and traditional birth attendants.  相似文献   
99.
100.
OBJECTIVE: Retrospective analysis was performed to determine the suitability of pulmonary homograft as an aortic valve substitute. METHODS: From January 1994 through June 1999, 147 patients (mean age, 32.2 +/- 17.3 years) underwent aortic valve replacement with either an aortic homograft (group 1: n = 103, 25 fresh antibiotic preserved and 78 cryopreserved) or a pulmonary homograft (group 2: n = 44, 11 antibiotic preserved and 33 cryopreserved). In group 1 a scalloped subcoronary technique was used in 64 patients, and a root replacement technique was used in 39 patients. In group 2 the scalloped subcoronary technique was used in 34 patients, and the root replacement technique was used in 10 patients. RESULTS: There were 131 operative survivors (group 1 = 91; group 2 = 40). Follow-up ranged from 2 to 62 months. In group 1 none of the patients had significant aortic regurgitation during the hospital stay. Three patients (all having undergone the scalloped subcoronary technique) had moderate aortic regurgitation after 6 to 32 months. In group 2, 10 patients (9 having undergone the scalloped subcoronary technique and 1 having undergone the root replacement technique) developed significant regurgitation: 2 intraoperatively, 5 in the early postoperative period before discharge from the hospital, and 3 during late follow-up 6 to 12 months postoperatively. Among the various risk factors analyzed for overall homograft failure, use of a pulmonary homograft was the single independent predictor of valve failure (odds ratio, 8.6; 95% confidence interval, 1.9-39; P =.006). CONCLUSION: Pulmonary homograft, when inserted by means of a scalloped subcoronary technique, is not a suitable aortic valve substitute.  相似文献   
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