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31.
Seventy seven antral biopsies were collected from patients attending endoscopy clinic at King Khalid University Hospital, Riyadh, Saudi Arabia during a period of six months between December 1988 to May 1989. Of these 69 (89.6%) showed chronic gastritis as well as Helicobacter-like organisms (HLOs) in the biopsy specimens while 63 (81.8%) of biopsies grew Helicobacter pylori on culture. These findings indicate a good correlation between the histological diagnosis of chronic gastritis and isolation of H. pylori on culture.  相似文献   
32.
Rats exposed on their first postnatal day to 100% nitrogen for 25 min developed hyperactivity and lower performance in passive avoidance task during development. Administration of MK-801 (0.5 mg/kg i.p.) 1 h before anoxia or (0.25 and 0.5 mg/kg) 1 h after completely reversed this behavioral impairment. Senescent rats (24-26 months) exposed to hypoxia (92% N2 + 8% O2) for 5 h failed in their performance in C.A.R., 30 days later. Pretreatment with MK-801 (1 mg/kg i.p.) completely reversed this impairment. These data suggest that activation of endogenous NMDA receptors produces different behavioral consequences in neonatal and senescent rats and that MK-801 administration close to exposure of animals to anoxia or hypoxia can prevent such damage, thus preventing behavioral impairments in postnatal as well as in senescent rats.  相似文献   
33.
Transient transfection of pLB2CAT constructs bearing short synthetic oligonucleotides derived either from the tyrosine hydroxylase (TH) promoter or other sources was used to examine functional cAMP regulatory element (CRE) activity in a variety of cell lines. The region containing only the putative TH CRE was found to be as or more effective in conferring cAMP responsiveness onto pLB2CAT (which employs the TK promoter) than the immediate 272 bp region of the TH promoter. Increases in CAT activity of 10- to 20-fold were observed in JEG-3 cells with a single insert of the TH CRE region (-31 to -54) in pLB2CAT, and the presence of a second insert generated only a modest further increase. This construct also responded to cAMP in 4 other cell lines tested but the degree of increase was less dramatic. Inserts containing the consensus 8 bp CRE motif embedded in other natural or artificial contexts served generally as weak functional CREs in all cell lines tested. In vitro analysis revealed that a specific protein-DNA complex apparently containing a single protein with a MW of 45-50 kDa was formed equally well with JEG-3 cell nuclear extract and CRE-bearing-TH and other fragments which produced dramatically different cAMP effects in vivo. These results suggest specificity in the effects of cAMP on different CREs which are dictated by contextual differences.  相似文献   
34.
Oncologic screenings of the populations in the areas with increased incidence of esophageal cancer have revealed Barrett's ulcer in 1 percent of the examinees. Endoscopic and cytologic characteristics of this condition are presented. Precancer changes--severe dysplasia--are most frequent in male Kazakhs (14.1 percent) aged 50 to 59 (14.7 percent). Subjects with Barrett's ulcer developing severe dysplasia, as evidenced by cytograms, should be included in the group of subjects at risk for carcinoma of the lower third of the esophagus and cardia.  相似文献   
35.
J S Li 《中华外科杂志》1989,27(10):629-33, 640
Serum aminogram changes were prospectively studied in 95 patients with enteric fistula and intraabdominal infection who was under total parenteral nutrition (TPN) therapy with Anfuming 14s. In patients with sepsis and starvation, the aminogram showed remarkably low total free amino acids before TPN therapy. In 81 survivors, free amino acids increased gradually to normal in 2 weeks after use of TPN and in 14 dead cases increased rapidly to a significantly higher peak at terminal stage. Both in survivors and nonsurvivors, phenylalanine level remained high during the study. In response to infection, proline was also elevated but to a lesser degree; the ratio of branched chain amino acid (BCAA) to aromatic amino acid (AAA) was lower than normal and the decrease of arginine was parallel to the severity of infection. We conclude that the ideal amino acids preparation for the starvated and septic patients should be high in BCAA and arginine but low in phenylalanine, administration of inappropriate exogenous amino acids in decompensated metabolic septic patients may bring about more harm than benefit, and in septic patients that the levels of serum phenylalanine and proline are elevated persistently along with the decrease of arginine level is a useful prognostic indication.  相似文献   
36.
We have recently reported that ligation of the CD44 cell surface antigen with A3D8 monoclonal antibody (mAb) triggers incomplete differentiation and apoptosis of the acute promyelocytic leukemia (APL)-derived NB4 cells. The present study characterizes the mechanisms underlying the apoptotic effect of A3D8 in NB4 cells. We show that A3D8 induces activation of both initiator caspase-8 and -9 and effector caspase-3 and -7 but only inhibition of caspase-3/7 and caspase-8 reduces A3D8-induced apoptosis. Moreover, A3D8 induces mitochondrial alterations (decrease in mitochondrial membrane potential DeltaPsi m and cytochrome c release), which are reduced by caspase-8 inhibitor, suggesting that caspase-8 is primarily involved in A3D8-induced apoptosis of NB4 cells. However, the apoptotic process is independent of TNF-family death receptor signalling. Interestingly, the general serine protease inhibitor 4-(2-aminoethyl)-benzenesulfonyl fluoride (AEBSF) decreases A3D8-induced apoptosis and when combined with general caspase inhibitor displays an additive effect resulting in complete prevention of apoptosis. These results suggest that both caspase-dependent and serine protease-dependent pathways contribute to A3D8-induced apoptosis. Finally, A3D8 induces apoptosis in all-trans-retinoic acid-resistant NB4-derived cells and in APL primary blasts, characterizing the A3D8 anti-CD44 mAb as a novel class of apoptosis-inducing agent in APL.  相似文献   
37.
A modified technique for the repair of moderate to severe cicatricial entropion has been developed. This method is unique, as it involves the creation of a bipedicled tarsoconjunctival advancement flap. The technique avoids the causes of surgical failure seen with standard tarsal fracturing procedures.  相似文献   
38.
Smoking and stroke.   总被引:2,自引:0,他引:2  
The purpose of this review is to evaluate literature published since 1978 on the association between smoking and stroke. Two cohort studies found a dose-response relationship between the amount of cigarettes smoked per day and the relative risk of stroke. Also, two of the cohort studies found that when smoking ceased, the risk of stroke lessened (p less than 0.001). Nine case-control studies found a significant association between smoking and stroke for men and women. The biological association between smoking and stroke is plausible and several epidemiologic studies are supportive of this thesis. Additional, well-designed epidemiologic studies with a sufficient sample size to detect reasonably small odds ratios or relative risks (thus providing adequate statistical power) are warranted.  相似文献   
39.
The neuroprotective effects of dizocilipine maleate (MK-801), a noncompetitive antagonist of the N-methyl-D-aspartate (NMDA) receptor/channel, were tested in the 4-vessel occlusion rat model of forebrain ischemia. Adult Wistar rats, treated intraperitoneally with MK-801 or saline using several different treatment paradigms were subjected to 5 (n = 208) or 15 (n = 62) min of severe, transient forebrain ischemia. In saline-treated animals, 15 min of ischemia (n = 13) produced extensive and consistent loss of pyramidal neurons in the CA1 zone of hippocampus. The degree and distribution of cell loss were not reduced by single dose preischemic administration of MK-801 at 1 (n = 7), 2.5 (n = 4), or 5 mg/kg (n = 8). In other animals subjected to 15 min of forebrain ischemia, multiple doses of MK-801 (5, 2.5, and 2.5 mg/kg) given immediately and at approximately 8 and 20 hr after cerebral reperfusion (n = 5) did not alter CA1 injury compared to saline-treated controls (n = 5). Five minutes of forebrain ischemia in saline-treated animals, (n = 82) resulted in significantly fewer (p less than 0.001) dead CA1 pyramidal cells and a greater variance compared to animals subjected to 15 min of ischemia. Power analysis of the preliminary saline-treated animals subjected to 5 min of ischemia (n = 22) indicated that 60 animals per group were necessary to detect a 15% difference between MK-801 and vehicle-treated groups. Multidose treatment with MK-801 (1 mg/kg) given 1 hr prior to 5 min of ischemia (n = 60) and again at approximately 8 and 16 hr after recirculation failed to attenuate hippocampal injury.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
40.
Following administration of phenothiazines for schizophrenia, a 25-year-old patient developed a malignant neuroleptic syndrome followed by bilateral periarticular ossification of the knees, with severely limited motion. Two years later, the patient regained useful motion after bilateral excision of the ossified tissue and intensive physiotherapy. No recurrence of ossification was observed 3 years after operation, and the patient has maintained almost normal motion.  相似文献   
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