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排序方式: 共有2215条查询结果,搜索用时 15 毫秒
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Metabolic abnormalities of gastrointestinal mucosa in celiac disease: An in vitro proton nuclear magnetic resonance spectroscopy study
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4.
Marker enzymes of Sertoli and germ cells were estimated to study the mechanism of action of antispermatogenic compound CDRI 84/35 in adult male rat testis. Animals were killed after 22, 41, and 64 days of treatment with antispermatogenic dose of CDRI 84/35 in order to evaluate the effect of the compound on spermatid, spermatocyte, and spermatogonial stages, respectively. Studies were also extended to a recovery period of 90 days. Results indicate a direction action of the compound on germ cells, with no apparent effect on Sertoli cells. Studies also show a massive depletion of postmeiotic germ cells after the treatment, with some damage to premeiotic germ cells as well. Reversibility of the compound was partial, with the marker enzymes of pre- and postmeiotic germ cells not being restored to control levels after withdrawal of treatment. 相似文献
5.
C Sekar S Rajasekaran Rajesh Kannan Shashidhar Reddy T Ajoy Prasad Shetty Yogesh K Pithwa 《The spine journal》2004,4(3):261-264
BACKGROUND CONTEXT: Administration of analgesic medication, before the actual onset of painful stimulus, is more effective than that after the onset of painful stimulus. This is the principle of preemptive analgesia. Although it is often considered superior to other forms of analgesia, its role in postoperative pain relief after lumbosacral spinal surgery has not been fully investigated. PURPOSE: To analyze the efficacy of preemptive analgesia with a single caudal epidural injection for patients undergoing surgeries on the lumbosacral spine by the posterior approach. STUDY DESIGN/SETTING: Randomized, double-blinded and controlled clinical trial. PATIENT SAMPLE: Eighty-two patients who underwent discectomy in the lumbosacral spine by the posterior approach, with or without instrumentation, were randomized to the control group (n=40) and to the study group (n=42). METHODS: Patients in control group received a single caudal epidural injection of 20 ml of normal saline. Patients in study group received a single caudal epidural injection of 20 ml containing bupivacaine and tramadol as the active agents. The time interval between this injection and the surgical incision was never less than 20 minutes in either of the groups. This facilitated enough time for the drug to get fixed to the nerve roots, leading to effective preemptive analgesia. OUTCOME MEASURES: Patients were monitored for postoperative pain immediately after surgery when they had completely recovered and regained consciousness from general anesthesia, and subsequently 4, 8, 12 and 24 hours thereafter. Pain was quantified using the visual analog scale (VAS) and the verbal rating scale (VRS). The time at which supplemental analgesic medication was first demanded in the postoperative period by the patient was also noted. RESULTS: The two groups were comparable for age, sex, body weight and the type of surgery they underwent. Because the data did not have a normal Gaussian distribution, the one-tailed Mann-Whitney test, being a nonparametric test, was adopted for statistical analysis. Accordingly, VAS and VRS values at all time intervals were significantly lower (p<.0001) in the study group as compared with the control group. This indicated significantly better pain relief in the study group. There was also a significant delay (p=.0041) in the first demand for supplemental analgesic medication in the postoperative period in the study group. No complication specific to the procedure was noted except for the development of postoperative urinary retention, which was transient and appropriately managed with urinary catheterization. CONCLUSIONS: Preemptive analgesia with a single caudal epidural injection of bupivacaine and tramadol is a safe, simple and effective method for postoperative pain relief. 相似文献
6.
Although abnormalities in serotonergic function have been the major focus of studies on suicidal behavior, several studies indicate that abnormalities of noradrenergic function may also be involved in the pathophysiology of suicide. In this paper, we have reviewed some of the noradrenergic studies in suicide, including studies of the biosynthetic enzyme for norepinephrine, tyrosine hydroxylase (TH), the receptors for norepinephrine, alpha- and beta-adrenergic receptors, as well as the signaling cascades linked to beta-adrenergic receptors. In general, these studies indicate that the protein expression of TH, as well as alpha2- and beta2-adrenergic receptors, is increased in the postmortem brain of suicide victims. More studies are needed in order to examine extensively the role of noradrenergic function in suicidal behavior. 相似文献
7.
H M Sharma C Dwivedi B C Satter K P Gudehithlu H Abou-Issa W Malarkey G A Tejwani 《Pharmacology, biochemistry, and behavior》1990,35(4):767-773
Maharishi-4 (M-4), an ayurvedic food supplement, was tested for anticarcinogenic and anticancer properties against 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary tumors in rats. The 6% M-4-supplemented diet protected DMBA-induced carcinogenesis by reducing both tumor incidence and multiplicity during initiation and promotion phases. The control animals who developed tumors when supplemented with M-4 diet for four weeks showed tumor regression in 60% of cases. There was no significant difference in the food intake or weight gain in rats who were on M-4-supplemented diet compared to control group. Possible mechanisms of action of M-4 are discussed. 相似文献
8.
Protection against 7,12-dimethylbenzanthracene-induced tumour initiation by protein A in mouse skin.
S Kumar Y Shukla A K Prasad A S Verma P D Dwivedi N K Mehrotra P K Ray 《Cancer letters》1992,61(2):105-110
Protein A is an immunostimulating glycoprotein obtained from Staphylococcus aureus Cowan I. Its antitumour activity is proven in various tumour models. Its ability to provide protection against tumour initiation by the chemical carcinogen 7,12-dimethylbenzanthracene (DMBA) has been investigated in the present study using a mouse skin model of two-stage carcinogenesis. Protein A was administered intraperitoneally (1 microgram/animal 20 g body wt.) twice a week for 2 weeks, prior to initiation by DMBA. The promotion was performed by twice weekly applications of 12-O-tetradecanoyl phorbol-13-acetate (TPA) (3 or 5 micrograms/animal in 100 microliters acetone). Protein A provided significant protection to animals from DMBA-induced tumour initiation as was observed by the decrease in cumulative number of tumours, percent of animals developing tumours, number of tumours per animal and rate of tumour growth. Our data indicate that protein A has anticarcinogenic properties. 相似文献
9.
Singh Shivendra V.; Haque Abida K.; Ahmad Hassan; Medh Rheem D.; Awasthi Yogesh C. 《Carcinogenesis》1988,9(9):1681-1685
In the present studies we have compared the levels of glutathione(GSH) and GSH-related enzymes in lung tumors and correspondingnormal tissues obtained from the same individuals. We have alsoimmunologically quantitated the relative amounts of glutathioneS-transferase (or GST-P) type antigen in tumors and adjacentnormal tissues from five patients. GST activities towards 1-chloro-2,4-dinitrobenzene (CDNB) and ethacrynic acid were found to beelevated in tumors from two out of five patients (patients #1and 4), whereas the activity towards these substrates was markedlysuppressed in the tumor tissue from one of the patients (#5).Immunotitration and Western blot studies using antibodies raisedagainst -type GST isoenzymes of human lung and placenta indicatedinduction of GST -type isoenzyme in tumors from patients #1and 4 and suppression of this isoenzyme in tumor from patient#5. The tumors from patients #2 and 3 did not show any increasein GST activity or GST -type antigen. Except for the tumor frompatient #5, the GSH content was higher in the tumors from otherpatients. GSH reductase activity was found to be elevated intumors of all the patients examined in this study. These resultsindicate that GSH and GSH related enzymes are differentiallyaltered in lung tumors and GSH levels and GST - or GST-P-typeisoenzyme(s) are not uniformly elevated in all tumors. 相似文献
10.
Role of Periductal and Ductular Epithelial Cells of the Adult Rat Pancreas in Pancreatic Hepatocyte Lineage: A Change in the Differentiation Commitment 总被引:4,自引:8,他引:4
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M. Sambasiva Rao Rama S. Dwivedi Anjana V. Yeldandi V. Subbarao Xiaodi Tan Mohammed I. Usman Shobha Thangada Mohan R. Nemali Sujata Kumar Dante G. Scarpelli Janardan K. Reddy 《The American journal of pathology》1989,134(5):1069-1086
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