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101.
An unusual case of dorsal spinal dysraphism in a four year old child is presented. Various abnormalities including diastematomyelia, an extradural arachnoid cyst arising from one of the two dural tubes, and lipomeningomyelocele with a related rib-like bony structure were demonstrated with Iohexol CT and subsequently confirmed at surgery. 相似文献
102.
J L Kinzie A L Silverman T P Gupta R R Peleman 《Gastroenterology Clinics of North America》1988,17(4):793-809
Pathologic reviews and clinical studies demonstrate that groups with increased cancer risk can be identified. It is estimated that about 3.5 per cent of colorectal cancers in this country are the result of known heritable cancer syndromes, such as familial polyposis. Much effort is currently being devoted to evaluation of biologic markers, such as cell surface antigens and their antibodies, ornithine decarboxylase, errors in DNA repair, abnormalities in metabolism of polyadenosine diphosphate, and application of molecular genetic techniques to identify patients with genetic cancer susceptibility. 相似文献
103.
Narayan Prasad Amit Gupta Raj K Sharma Archna Sinha Ramesh Kumar 《Peritoneal dialysis international》2007,27(1):42-47
OBJECTIVE: To determine the impact of nutritional status on peritonitis in patients on continuous ambulatory peritoneal dialysis (CAPD) in a developing country. METHODS: 56 patients with end-stage renal disease on CAPD were randomly selected for this study. These patients were assessed for nutritional status and peritonitis episodes. Nutritional parameters were assessed by anthropometry, diet, body mass index (BMI), Nutritional Risk Index (NRI), serum albumin level, and Subjective Global Assessment (SGA). Based on SGA, patients were categorized into either group 1 (malnutrition, n = 31) or group 2 (normal nutritional status, n = 25). Peritonitis was considered the primary outcome and was compared between the two groups. RESULTS: Demographic profiles, Kt/V, creatinine clearance, and mean follow-up of the two groups were similar. Number of peritonitis episodes was significantly higher in patients with malnutrition (25/31) compared to patients with normal nutritional status (4/25) (p = 0.001). Mean peritonitis rate per patient per year was also significantly higher in patients with malnutrition (0.99 +/- 1.07) compared to patients with normal nutritional status (0.18 +/- 0.42) (p = 0.007). On univariate analysis, malnutrition based on SGA (p = 0.009), NRI (p = 0.02), serum albumin level (p = 0.005), and calorie intake (p = 0.006) was a significant predictor of peritonitis. On multivariate Cox regression analysis, only SGA (p = 0.001, odds ratio 0.08, 95% confidence interval 0.02-0.36) was found to be a significant predictor of peritonitis. On general linear model, the observed power of prediction of peritonitis was 0.96 based on SGA. On Kaplan-Meier survival analysis, peritonitis-free survival in patients with normal nutrition (42 months) was significantly higher compared to patients with malnutrition (21 months) based on SGA (log rank p = 0.003). CONCLUSION: We conclude that peritonitis rate is high in patients with malnutrition and that malnutrition indices, especially SGA, can predict the peritonitis rate in CAPD patients. 相似文献
104.
S. Sukhija V. K. Gupta A. Shah S. Thiel P. U. Sarma & T. Madan 《Scandinavian journal of immunology》2004,59(6):624-624
Activation of complement pathways, leading to production of C3a and C5a anaphylatoxins, has been postulated in the pathogenesis of asthma and allergic airway inflammation. The present study was undertaken to investigate the role of mannan-binding lectin (MBL), an initiator of the lectin pathway of complement, in asthma and allergic rhinitis. MBL levels and MBL-induced complement activity were determined in 19 patients of bronchial asthma with allergic rhinitis and 20 unrelated, age-matched controls of Indian origin. MBL levels and activity were correlated with percent eosinophilia and percent predicted FEV1 values of the patients. Association of single nucleotide polymorphisms (SNPs) in exon 1 and intron 1 of the MBL with the disease, clinical markers, MBL levels and MBL-induced complement activity was analysed using standard statistical tools. Significantly higher MBL levels and activity were observed in patients of bronchial asthma with allergic rhinitis as compared to the controls. We identified five SNPs, of which two, A816G in exon 1 and G1011A in intron 1 of the MBL, were novel. SNP G1011A was significantly associated with the disease ( P = 0.0024, OR = 5.8696, 95% CI: 1.7316 < OR < 19.8963). Individuals with 'A' allele at position 1011 showed increased MBL levels, activity and disease severity. Our results suggest that 'A' allele at position 1011 leading to high MBL levels and complement activity may be contributing to the severity of bronchial asthma and allergic airway inflammation. 相似文献
105.
Garima Chawla Piyush Gupta R Thilagavathi Asit K Chakraborti Arvind K Bansal 《European journal of pharmaceutical sciences》2003,20(3):305-317
This study deals with the generation and characterization of various solid-state forms of celecoxib, a selective cyclooxygenase-2 (COX-2) inhibitor. The drug was subjected to polymorphic screen using different solvents to explore the possibility of existence of different solid forms. N,N-Dimethyl acetamide (DMA) and N,N-dimethyl formamide (DMF) yielded solvates in 1:1 stoichiometric ratio. Quench cooling of the melt resulted in amorphous form of the drug. All these solid-state forms were characterized by thermoanalytical (DSC, TGA, HSM), crystallographic (XRD), microscopic (polarized, SEM), spectroscopic (FTIR), and elemental analysis techniques. Solubility and van't Hoff studies were carried out for their thermodynamic interpretation. Influence of morphology of different solid-state forms on flow behavior was also investigated. Molecular modeling studies were used to elucidate the interaction between solute and solvent molecules in the solvate. 相似文献
106.
Manjula K. Gupta Karen Seifarth Sharad D. Deodhar O. P. Schumacher 《Journal of clinical laboratory analysis》1987,1(1):124-128
A sensitive, simultaneous sandwich enzyme immunoassay for TSH was evaluated especially for its ability to distinguish hyperthyroid patients from the euthyroid population. A total of 140 patient samples was analzyed by this assay as well as with a two-step sandwich radioimmunoassay. The diagnostic sensitivity of the thyrotropin assay was 92.5% and the specificity was 88%. False negatives by thyrotropin assay included two patients with Graves' disease who were being treated with propranolol at the time of testing and one patient who was considered hyperthyroid while receiving synthroid. Twelve patients with elevated free thyroxine index levels were considered euthyroid and 50% of these had thyrotropin values that were undetectable; most were elderly patients with nonthyroidal illnesses. Although the thyrotropin enzyme immunoassay had good sensitivity and precision for the detection of hyperthyroidism, our data suggest the limitation of a single thyrotropin determination in establishing the euthyroid state, especially in elderly patients with associated nonthyroidal illnesses and hyperthyroxinemia. 相似文献
107.
Sturge-Weber syndrome is a rare neurocutaneous disorder characterized by a facial nevus flammeus and extensive angiomatous changes involving the leptomeninges, the dura, and vessels of the gray and white matter. Oculodermal melanocytosis is characterized by hyperpigmentation of the facial skin in the distribution of the ophthalmic, maxillary, and occasionally mandibular division of the trigeminal nerve. 相似文献
108.
109.
Analysis of DNA adducts in putative premalignant hepatic nodules and nontarget tissues of rats during 2-acetylaminofluorene carcinogenesis 总被引:3,自引:0,他引:3
Exposure of rats to a standard four-cycle feeding regimen of 0.06% 2-acetylaminofluorene (AAF) results in the formation of putatively premalignant hepatic nodules, but the types and magnitude of DNA adducts formed in these nodules has not been previously examined. By using a sensitive 32P-adduct assay (R. C. Gupta, Cancer Res., 45: 5656-5662, 1985), we analyzed the DNA adduct lesions in individual hepatic nodules at various times during and after exposure to AAF. Kidney, spleen, and testis were included as nontarget tissues. No qualitative difference was observed in the DNA adducts found in hepatic nodules and nontarget tissues; however, quantitative differences occurred. At least one unknown and two known (dG-C8-AF and dG-N2-AAF) DNA adducts were detected, with dG-C8-AF being predominantly (96-98%) formed, in all tissues examined. At the end of the first three weeks of AAF feeding, the concentration of the deacetylated adduct dG-C8-AF in liver (223 fmol/micrograms DNA) was found to be about 2, 6, and 5 times higher than in kidney, spleen, and testis, respectively. The concentration of the N2-acetylated adduct in liver (4.5 fmol/micrograms DNA) was 4-fold higher than in kidney and strikingly higher (51- and 42-fold, respectively) than in spleen and testis. At the end of the fourth feeding cycle, total DNA adducts measured in the hepatic nodules ranged from 30-100 fmol/micrograms DNA, while the "surrounding liver," kidney, spleen, and testis showed 235, 218, 62, and 28 fmol adducts/micrograms DNA, respectively. Sixty days following the cessation of AAF, the binding in both the persistent nodules and liver had decreased to 7% of their respective levels measured at the end of the fourth cycle, while adducts in kidney, spleen, and testis were 32%, 18% and 19%. After 88 days, the binding levels in the nontarget tissues declined further, but no additional adduct removal occurred in the nodules. Our data indicate that (a) although the metabolic apparatus for activation of AAF is diminished in the hepatic nodules, a significant level of adduct formation occurs in the cells of this putative, premalignant lesion, and (b) unlike in the nontarget tissues, repair processes in the premalignant nodules may not be operative several weeks after the cessation of AAF exposure. 相似文献
110.
K. K. Tangri G. P. Gupta S. Vrat 《Naunyn-Schmiedeberg's archives of pharmacology》1989,339(5):557-563
Summary The effects of microinjection of histamine and its antagonists into mesencephalic nucleus dorsalis raphe, were investigated on mean arterial pressure and heart rate in cats to elucidate the nature and role of histaminergic receptors in cardiovascular regulation. Microinjection of histamine (5 and 10 g) into nucleus dorsalis raphe elicited both inhibitory and excitatory cardiovascular responses respectively. On the other hand, microinjection of H2-receptor blocker, cimetidine (10 g) resulted in hypertension and tachycardia while H1-receptor antagonist, mepyramine (10 g) microinjection evoked hypotension and bradycardia. Furthermore, local pretreatment with cimetidine and mepyramine blocked the inhibitory and excitatory cardiovascular responses of graded doses of histamine microinjection. These H1 and H2 receptors are localized in nucleus dorsalis raphe since microinjection of histamine into adjoining neural structures did not evoke any cardiovascular change. Furthermore, both the inhibitory and excitatory cardiovascular responses to histamine microinjection could not be observed in animals with spinal cord transection and in animals pretreated with p-chlorophenylalanine while they could be observed in bilateral cervical vagotomized animals. Thus, it appears that these cardiovascular responses to microinjection of histamine into nucleus dorsalis raphe, are due to modulation of serotonergic bulbospinal influence on sympathetic preganglionic neurones in the spinal cord. Moreover, the excitatory cardiovascular responses of high dose of histamine (10 g) seem to result from a local release of noradrenaline since they were blocked by prior microinjection of guanethidine and piperoxan into nucleus dorsalis raphe. A release of noradrenaline in turn, modulates the activity of the neurones of the nucleus by acting on adrenoceptors and thereby alters the activity of sympathetic preganglionic neurones. These adrenoceptors appear to be of 1 type (Saxena et al. 1985, 1987) since phenylephrine microinjection evoked excitatory cardiovascular responses could be blocked by piperoxan.
Send offprint requests to K. K. Tangri at the above address 相似文献