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221.
To determine the physiology of acid secretion after gastrocystoplasty with the body of the stomach we performed a prospective standardized 3-day study in 13 children (median age 12.5 years) who had undergone bladder augmentation/replacement (median postoperative period 2 years). Urinary pH and titratable acid, and serum gastrin levels were measured after gastric distention with a meal and bladder distention with urethral filling at baseline and after medication with a histamine-2 receptor antagonist or an anticholinergic agent. Five children underwent cystoscopy and biopsy of the gastric and native segments of the gastrocystoplasty.

In the fasting state pH was neutral, there was no titratable acid in the urine and serum gastrin level was normal in all cases. After a meal urinary acid secretion and serum gastrin level increased markedly. After each medication half of the patients demonstrated marked inhibition of urinary acid secretion after a meal while response was partial in the remainder. In none of the patients was there significant alteration in the pattern of gastrin secretion. Bladder distention did not result in urinary acid secretion or gastrin secretion. The cystoscopic and histological appearance of the native bladder and stomach segment of the gastrocystoplasty in the 5 patients was normal. We conclude that the gastric body segment used in gastrocystoplasty continues to secrete acid as though it were part of the stomach. The secretion of acid in the urine can be decreased with histamine-2 receptor antagonist or anticholinergic medication.  相似文献   

222.
The hexane extract from Nutmeg, the seed ofMyristica fragrans significantly inhibited hepatic drug-metabolizing enzyme activity. Through systematic fractionation by SiO2 column and vacuum liquid chromatography monitoring by bioassay, three components, myristicin, (I), licarin-B(II) and dehydrodiisoeugenol(III) were isolated as active principles. Compounds II and III, with a single treatment (200 mg/kg, i.p.) showed not only a significant prolongation of hexobarbital-induced sleeping time but also a significant inhibition of aminopyrine N-demethylase and hexobarbital hydroxylase activities in mice. Compounds I and II provoked a sleep episode at a subhypnotic dose of HB, suggesting that they posses CNS-depressant properties.  相似文献   
223.
A sensitive and simplified HPLC assay of fluconazol is described. The calibration curve of fluconazol in plasma ranging 0–10 μ g/ml was linear with the correlation coefficients of 0.9900. The limit of detection was 0.3 μ g/ml. The average recovery of the drug was 89.1±9.05%. After oral administration of single dose(150mg) of fluconazol in man, Cmax and Tmax were 3 μg/ml and 4hr., respectively.  相似文献   
224.
D Boyd  G Florent  P Kim  M Brattain 《Cancer research》1988,48(11):3112-3116
At present, there is a lack of availability of differentiation markers for colon carcinoma. This may, in part, be a consequence of the diversified function of the normal human colon. This study addresses the possibility that the expression of urokinase and its receptor is inversely related to differentiation in colon carcinoma. Six colon carcinoma cell lines including three well-differentiated (CBS, GEO, FET) and three poorly differentiated ones (HCT116, HCT116b, RKO) were screened for urokinase receptor display and secretion of the plasminogen activator. A radioreceptor assay was used to determine receptor levels. Binding of radioactive urokinase to colon cells was saturable, specific, and time dependent. Cell-bound 125I-labeled protease was unaffected by the presence of epidermal growth factor, low-molecular-weight urokinase, plasminogen, or transferrin. Time course studies revealed that maximum amounts of radioactive tracer were bound in a 30-min period with no change occurring over the course of a 90-min incubation. Scatchard analysis of ligand binding indicated that the well-and poorly differentiated cells could be separated on the basis of receptor display; the aggressive RKO, HCT116, and HCT116b expressed in excess of 10(5) sites per cell, while the more indolent CBS, GEO, and FET possessed less than 1.5 X 10(4) receptors per cell. The colon carcinoma cells were also analyzed for urokinase in the conditioned medium. Low levels of the plasminogen activator (0.8 to 1.3 ng/ml/10(6) cells/72 h) were associated with the more "mature" cells. This was in contrast to the elevated levels of the protease (3.9 to 11.4 ng/ml/10(6) cells/72 h) present in the medium derived from the more aggressive cells (HCT 116, HCT116b, RKO). Thus, secreted urokinase and/or the expression of cellular receptor for the plasminogen activator may provide useful measurements of the degree of undifferentiation of in vitro colon carcinoma.  相似文献   
225.
The feasibility of using beta,beta'-monochloromethylene diadenosine 5',5"'-P1,P4-tetraphosphate (AppCHCl-ppA) as an antithrombotic agent was studied in a rabbit intracarotid cannula thrombosis model previously shown to be sensitive to antiplatelet agents. This analogue, having a P-C-P bridge in place of a P-O-P internucleoside linkage, has been found resistant to phosphodiesterase activity. Rabbits were infused with the dinucleotide at a dose of 50 mg per kg over a 2-hr period, at a controlled rate by pump. A 1-cm length of polyethylene cannula (1 mm i.d.) was tied into the carotid artery. Animals were stable under general anesthesia during the entire period of the experiment. In the control group, 16 of 20 animals formed clots, an incidence of 80%, whereas in the test animals, 6 of the 20 formed clots (30% incidence, P < 0.05). After preincubation of whole blood with 50 microM AppCHClppA at 37 degrees C for up to 3 hr, a consistent suppression of ADP-induced platelet aggregation was observed. The present study suggests that AppCHClppA may be useful as an antithrombotic agent in certain clinical situations, such as hemodialysis, arteriovenous shunts, and introduction of artificial heart valves. It may also possibly prevent extension of recent clots. The toxicity and metabolism of AppCHClppA have, however, yet to be explored.  相似文献   
226.
Regional cerebral blood flow (CBF) in eight patients in a persistent vegetative state was measured and compared with that in five healthy volunteers. The patients were classified into three groups: Group 1 (locked-in syndrome) consisted of a single patient, Group 2 (typical vegetative state) of five patients, and Group 3 (prolonged coma) of two patients. CBF was measured early after onset by single photon emission computed tomography with 123I-N-isopropyl-p-iodo-amphetamine and/or 99mTc-hexamethyl-propyleneamine oxime. The regions of interest (ROIs) were the bilateral frontal, temporal, parietal, occipital, and cerebellar areas and basal ganglia. The values obtained in these areas were averaged, and the ratio for each ROI [(the value in the ROI/the mean value) x 100] was calculated. "Hyperfrontal distribution" of CBF was found to be rare in both the normal condition and the vegetative state. Higher CBF values were noted in the left than in the right frontal area in four of the five volunteers but in only four of the eight patients. CBF distribution in the frontal lobe was characteristic for each group: Group 1 showed high CBF bilaterally, although the elevation was statistically significant only on the right side, and Group 3 exhibited significantly low values. In Group 2, CBF was variable but, for the most part, within normal limits. Awareness was closely correlated with frontal lobe function and alteration of CBF in the frontal region.  相似文献   
227.
The Src-homology 2 domain-containing, leukocyte-specific phosphoprotein of 76 kDa (SLP-76) is a hematopoietic adaptor that plays a central role during immunoreceptor-mediated activation of T lymphocytes and mast cells and collagen receptor-induced activation of platelets. Despite similar levels of expression in macrophages, SLP-76 is not required for Fc receptor for immunoglobulin G (IgG; FcgammaR)-mediated activation. We hypothesized that the related adaptor SLP-65, which is also expressed in macrophages, may compensate for the loss of SLP-76 during FcgammaR-mediated signaling and functional events. To address this hypothesis, we examined bone marrow-derived macrophages (BMM) from wild-type (WT) mice or mice lacking both of these adaptors. Contrary to our expectations, SLP-76(-/-) SLP-65(-/-) BMM demonstrated normal FcgammaR-mediated activation, including internalization of Ig-coated sheep red blood cells and production of reactive oxygen intermediates. FcgammaR-induced biochemical events were normal in SLP-76(-/-) SLP-65(-/-) BMM, including phosphorylation of phospholipase C and the extracellular signaling-regulated kinases 1 and 2. To determine whether macrophages functioned normally in vivo, we infected WT and SLP-76(-/-) SLP-65(-/-) mice with sublethal doses of Listeria monocytogenes (LM), a bacterium against which the initial host defense is provided by activated macrophages. WT and SLP-76(-/-) SLP-65(-/-) mice survived acute, low-dose infection and showed no difference in the number of liver or spleen LM colony-forming units, a measure of the total body burden of this organism. Taken together, these data suggest that neither SLP-76 nor SLP-65 is required during FcgammaR-dependent signaling and functional events in macrophages.  相似文献   
228.
Natural killer/T-cell lymphoma (NKTL) and peripheral T-cell lymphomas (PTCL) are prevalent in the Asian population and exhibit a high association with the Epstein-Barr virus (EBV). Moreover, differentiation of these two groups is often difficult and problematic. We investigated 35 cases of NKTL (22 nasal cases and 13 extranasal cases) and 30 cases of PTCL in terms of their clinical features, immunohistology, EBV positivity, EBV strain-type polymorphism and latent membrane protein 1 (LMP1) deletion variant distribution. Eighteen cases (82%) of nasal NKTL and seven (54%) of extranasal NKTL showed EBV positivity by EBV in situ hybridization. Fifteen cases (50%) of PTCL revealed EBV positivity. EBV strain type A was predominant in NKTL (18:5), and EBV strain types A and B were distributed evenly in PTCL (6:6). EBV-positive patients had significantly shorter survival than EBV-negative patients (P < 0.05), and EBV positivity correlated with advanced clinical stage (P < 0.05). Patients harboring type A EBV showed slightly poorer prognoses than those having type B, though it was not obviously statistically different (P = 0.07). The LMP1 deletion variant was prevalent in both NKTL (three wild-type LMP1, 15 deletion variants) and PTCL (three wild-type LMP1, eight deletion variants, two coexistent forms) patients, but did not have prognostic impact. Our results indicate that EBV acts as a negative prognostic factor in NKTL and PTCL, and that the intrinsic properties of a specific viral strain might influence the clinical behavior of these diseases.  相似文献   
229.
Fine-needle aspiration biopsy (FNAB) is an accurate, cost-effective method of evaluating lymphomas. The neutrophil-rich variant of anaplastic large cell lymphoma (NR-ALCL) is a rare non-Hodgkin lymphoma. To our knowledge, we present thefirst study of NR-ALCL by FNAB cytology. Histologic confirmation was available for both patients. Both cases were positive for Ki-1 (CD-30) and were either T-cell or null-cell phenotype. FNAB specimens were highly cellular with a single-cell pattern composed of pleomorphic tumor cells, "hallmark" tumor cells, and a background rich in neutrophils that occasionally obscured tumor cells. Diagnosis on FNAB is difficult owing to the rarity of this tumor, its resemblance to Hodgkin lymphoma and other non-Hodgkin lymphomas that express CD30, its similarity to an infectious process, and its occasional confusion with metastatic carcinoma and melanoma. Reproducible cytologic features usually are present, and the diagnosis can be made conclusively by FNAB in conjunction with ancillary studies.  相似文献   
230.
A randomized comparison of pre-and post-experimental design was used to examine the effects of a fall prevention exercise program (FPEP) on muscle strength, ankle flexibility, balance, instrumental activities of daily living (IADLs), and depression for the community-dwelling elderly in Korea. Twenty-two subjects were assigned to an experimental group and twenty-three to a control group. The experimental group participated in a 4-day-per week FPEP of 8 weeks duration, twice a week by direct instruction and twice a week with videotaped instruction by the program instructor at each senior center. The eight-week FPEP turned out to be significantly effective in enhancing muscle strength, ankle flexibility and balance, and in reducing depression, after intervention among community-dwelling elderly in Korea. IADLs, however, was not changed by the intervention. Further research with a larger sample and longer follow up period is needed to expand our understanding about the effects of FPEP. Future study is also recommended to differentiate between the effects of FPEP by direct instruction and by videotaped.  相似文献   
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