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11.
PROBLEM: Development of an orally administered abortifacient. METHODS: Subjects were female Wistar rats, weighting 150 to 200 g at the time of experiments. Praneem (a purified extract of neem Azadirachta indica) at a dose of 0.6 ml was given orally from day 8 to 10 after confirming presence and number of implants surgically on day 7 of pregnancy. The animals were examined again under anesthesia on day 15 of pregnancy to check the number of developing embryos. Controls received an equivalent regime of peanut oil. The number and size of implants were counted five days after treatment. RESULTS: Complete resorption of embryos was observed on day 15 of pregnancy in every animal treated with Praneem in contrast to normally developing embryos in rats given peanut oil. In repeat batch experiments, it was established that the effect of the treatment was reversible and animals regained fertility in cycles subsequent to treatment with Praneem. Cytokines of TH1 type, i.e., gamma interferon and TNF, were raised on administration of Praneem, which may be the probable cause of pregnancy termination. CONCLUSIONS: Praneem on oral adminstration can cause termination of pregnancy in rodents, and the action is probably mediated by TH1 cytokines.  相似文献   
12.
Electret behaviour of surgically removed kidney stones through thermally stimulated polarization and thermally stimulated depolarization has already been reported by the authors. To develop an understanding of the conduction mechanism of such samples, d.c. conductivity was studied as a function of temperature and electric field. Temperatures from 308 to 448 K and fields from 0.5 X 10(6) to 2.5 X 10(6) V/m were used on the compressed powder pellet of a kidney stone. Conductivity was found to be 6 X 10(-11) s/m to 1.0 X 10(-11) s/m in the studied temperature range. Possibility of semiconduction is shown and it is suggested that kidney stone is a partially compensated semiconductor of n-type. The field independence of conductivity is observed at higher temperatures. The slopes of current density versus field curves suggest a warm electron effect.  相似文献   
13.
Twenty-three leprosy patients have been studied in an endemic area before institution of chemotherapy. These were comprised of ten lepromatous leprosy, four borderline lepromatous and nine tuberculoid leprosy cases on basis of clinical features, bacteriological and marphological indices. Histopathology of skin biopsies classified two as truly polar lepromatous leprosy (LL) and three as polar tuberculoid (TT), while the remaining eighteen were at various stages of evolution towards lepromatous or tuberculoid end of the spectrum. All lepromatous and borderline leprosy patients showed negative delayed hypersensitivity reaction with lepromin, but six out of fourteen patients in this category gave positive reaction with PPD. Blast transformation with PHA of peripheral leucocytes from all cases of lepromatous leprosy cultured in standard AB serum was depressed in comparison with cells from normal controls. 3H-thymidine incorporation in DNA of leucocytes in presence of leprolin was lower in cells of lepromatous leprosy group as compared to those from tuberculoid and borderline cases. There was lack of production of macrophage aggregation factor in all except one case of lepromatous leprosy while the test for this factor was positive for most of the tuberculoid leprosy patients. The homing characteristics of lymphocytes tagged with 51Chromium into liver and spleen of test mice were altered from the normal pattern in a large number of leprosy cases.  相似文献   
14.
We compared the performance of two PCR assays, an IS6110-based in-house protocol and the COBAS AMPLICOR MTB PCR (COBAS MTB) system, for the detection of Mycobacterium tuberculosis complex in 43 human lymph node samples from 40 patients. For the in-house PCR and the COBAS MTB assays, respectively, sensitivities were 87.5% versus 45.5% (P < 0.05), specificities were 100.0% versus 91.3% (P > 0.05), and inhibition rates were 4.8% versus 19.5% (P < 0.05). For the COBAS MTB system, additional N-acetyl-L-cysteine-NaOH pretreatment of the samples changed neither the inhibition rate nor the sensitivity significantly.  相似文献   
15.
We describe a simple HPLC method which is suitable for the routine confirmation of immunoassay positive amphetamine urine samples. The precolumn derivisation method employing sodium naphthaquinone-4-sulphonate was found to have adequate sensitivity, selectivity and precision for the measurement of amphetamine, methamphetamine, 3,4-methylenedioxymethamphetamine (MDMA), 3,4-methylenedioxyamphetamine (MDA), and 3,4-methylenedioxyethylamphetamine (MDEA) at 500 microg/l cutoff level for confirmatory analysis of amphetamines in urine. The specificity of the method is enhanced by detecting the peaks at two different wavelengths. The ratios of the peak heights measured at the two wavelengths were different for each of the 5 amphetamines analysed. There was no interference from other phenylethylamine analogues that are commonly found in "over the counter" preparations. The HPLC method is compared to a commercial TLC system for detecting amphetamines in urine of drug abusers attending drug rehabilitation programmes. The HPLC confirmatory method described is a viable alternative to GC or to the more complex and costly GC-MS techniques for confirming amphetamine, methamphetamine, MDMA, MDA and MDEA in urine of drug abusers especially when used in a clinical care setting.  相似文献   
16.
The present study was undertaken to evaluate the effects of hypoxia and hypercapnia on circulatory parameters during acute normovolemic hemodilution. Cats anesthetized with a mixture of alpha-chloralose and urethane were maintained by positive pressure ventilation. Muscles were paralysed by intramuscular vecuronium (0.1 mg/kg) to eliminate reflex respiratory movements. Cats were exposed to hypoxia (12% O(2) and 7% O(2)) and hypercapnia (4% CO(2) and 7% CO(2)) at normal hematocrit (Ht 40.1 +/- 2.8%) and then at graded levels of normovolemic hemodilution (Ht 24.0 +/- 2.0% and Ht 13.0 +/- 1.5%, respectively). Left ventricular pressure (LVP), LV dP/dt(max), arterial blood pressure (ABP), heart rate (HR), and right atrial pressure (RAP) were recorded on a polygraph. Cardiac output (CO) was measured using a cardiac output computer. Hemodilution per se did not produce any significant change in ABP, RAP or LV dP/dt(max), however, it produced a significant rise in HR and a significant fall in total peripheral resistance (TPR). Exposure to hypoxic gas mixtures caused significant increases in HR and CO at control Ht; but after hemodilution it caused the reverse effects. Hypercapnia did not produce any significant effect on ABP, LV dP/dt(max) or RAP either at control Ht or after hemodilution. Hypercapnia produced a fall in HR, CO and stroke volume (SV) at normal Ht and percent fall in HR response was enhanced following hemodilution. The reversal of chronotropic response to hypoxia and enhanced bradycardia response to hypercapnia, under conditions of acute normovolemic hemodilution would be deleterious as the tissues would become more hypoxic. Such a response may be attributed to altered control mechanisms under such conditions of severe stress.  相似文献   
17.
18.
IntroductionLiving-donor liver transplantation (LDLT) has been mostly suspended and deceased-donor living transplantation activity has been considerably reduced because of coronavirus disease 2019 (COVID-19). We modified our protocols and procedures in line with COVID-19 guidelines. Since the restructuring, we have performed 20 LDLTs. Our study reports the outcomes of these cases and demonstrates the feasibility of LDLT during this pandemic.Materials and MethodsThe changes were influenced by experiences and communications from across the globe. A month-long self-imposed moratorium was spent in restructuring the program and implementing new protocols. Twenty LDLTs were performed between April 18 and September 15 using the new protocols. Our experience includes 2 simultaneous liver-kidney transplants, 1 ABO-incompatible LDLT, and 1 pediatric case (age 11 months).ResultsNineteen patients recovered and 1 patient died. We maintained our postoperative immunosuppression protocol without many changes. Major complications were observed in 30% of recipients but none of the donors. One recipient was infected with COVID-19 during the postoperative period. A donor-recipient couple contracted COVID-19 after discharge from the hospital. All patients recovered from COVID-19 and liver enzymes were unaffected.ConclusionThis study represents a microcosm of experience in LDLT during the COVID-19 era. Outcomes of LDLT are not affected by COVID-19 per se, provided that we make necessary changes.  相似文献   
19.
This study assessed whether the goodness of fit--between early adolescents temperaments and their parents and peers demands, or "ethnotheories", regarding temperament--was more related to adjustment than were acontextual measures of temperament alone. Data from the Pennsylvania Early Adolescent Transitions Study, a short-term longitudinal investigation of 153 adolescents from the beginning of sixth grade to the end of seventh grade, were used. Temperament was indexed by the nine attributes measured by the Revised Dimension of Temperament Survey, and the measures of demands regarding temperament were derived from different versions of this instrument. Adjustment was indexed by teacher ratings of academic and social competence and by parent ratings of problem behaviors. At the end of Grade 6 and the beginning of Grade 7, the number of significant relations between the adjustment measures and the fit scores tended to be greater than the number of significant relations between adjustment and temperament, measured alone. Moreover, groups formed on the basis of high vs. low temperament fit showed differential adjustment scores: adolescents in the low fit group in regard to both peer- and parent-demands received lower teacher ratings of scholastic competence, and higher parent ratings for conduct and school problems, than did the adolescents in the high fit group.  相似文献   
20.
Ten cases of psoriasis were studied to see the pattern of histological resolution and to evaluate clinico-histological correlation in psoriasis following weekly methotrexate therapy. Five sequential biopsies were taken in each patient. Scaling was first to regress followed by induration and erythema in 18, 26 and 35 days, respectively. Uniform granular layer appeared in 4 days, stratum corneum became orthokeratotic in 7 days, mitotic activity got restricted to basal layer in 7 days and rete ridges elongation was reduced to half in 11 days. Mild acanthosis, cellular infiltrate and vascular dilatation pesisted even after full clinical regression. Interestingly, 5 out of 10 biopsies revealed increase in cellular infiltrate and oedema after first methotrexate pulse.  相似文献   
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