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排序方式: 共有3168条查询结果,搜索用时 46 毫秒
41.
Graham DY Hoffman J Anderson SY Qureshi W Osato MS El-Zimaity HM 《Alimentary pharmacology & therapeutics》1999,13(2):169-172
BACKGROUND: Although many combination therapies have been proposed, there is still interest in identifying simple, inexpensive, effective protocols that have high rates of success. AIM: To investigate the role of the new soluble form of bismuth, ranitidine bismuth citrate, in twice-a-day therapy for Helicobacter pylori infection. METHODS: Patients with histologically and culture proven H. pylori infection received ranitidine bismuth citrate 400 mg, tetracycline HCl 500 mg, and clarithromycin 500 mg, each b.d. for 14 days, followed by 300 mg ranitidine once a day for 4 additional weeks. Outcome was assessed 4 or more weeks after the end of antimicrobial therapy by repeat endoscopy with histology and culture (49 patients) or urea breath testing (14 patients). RESULTS: Sixty-three patients completed the therapy, 59 men and four women (average age 56.7 years; range 31-75 years). All patients had clarithromycin-susceptible strains prior to therapy. H. pylori infection was cured in 94% (95% CI: 85-98%). There was a therapy failure in one patient who took the medicine for only 1 day and stopped because of side-effects. Three of the isolates from treatment failures were available post-failure; two were clarithromycin-resistant and one was susceptible. Side-effects were severe in two patients (3%) and moderate in three (primarily diarrhoea). CONCLUSIONS: Twice-a-day ranitidine bismuth citrate, tetracycline, clarithromycin triple therapy was well tolerated and effective for the treatment of H. pylori infection in patients with clarithromycin-susceptible H. pylori. 相似文献
42.
The involvement of dopamine receptors in the inhibitory effect of Cholecystokinin octapeptide on ingestive behaviour was investigated. Male rats were infused intraorally with a 1 M solution of sucrose and the amount ingested after treatment with the dopamine receptor agonist apomorphine was compared with that after treatment with Cholecystokinin octapeptide. The test allows a distinction between the consummatory aspects of ingestive behaviour, i.e. responses used to ingest food, from the appetitive aspects, i.e. responses used to obtain food, because it ignores the latter aspects. Comparisons were also made between the effects of apomorphine and Cholecystokinin octapeptide on pellet intake, a test in which the rat has to display appetitive ingestive behaviour. Injection of apomorphine (400 μg) increased the concentration of plasma apomorphine within 0.3 min and the concentration of dopamine in the cerebrospinal fluid within 1 min of injection and induced behavioural stereotypes within 10 min in food-deprived male rats. Plasma apomorphine and cerebrospinal fluid dopamine levels had decreased by 30 min and the behavioural stereotypies had decreased by 40 min after the injection. Injection of apomorphine also inhibited the consumption of food pellets and the ingestion of sucrose. Inhibition of pellet and sucrose ingestion paralleled the effect of apomorphine on Stereotypie behaviour. Thus, injection of a dopamine receptor agonist is followed by alterations in plasma levels of the agonist, cerebrospinal fluid dopamine levels and in Stereotypie and ingestive behaviour which occur in parallel, in an inverted U-shaped manner and with a temporal delay between each event. These results show a close correlation between dopamine receptor stimulation and inhibition of ingestive behaviour. However, reversal of the inhibitory effect of apomorphine on ingestive behaviour required pretreatment with a lower dose of a dopamine receptor antagonist (cis-flupentixol) (0.1 mg) than reversal of Stereotypie behaviour (0.8 mg). The effect of dopamine receptor stimulation on consummatory ingestive behaviour is thus relatively weak and not secondary to the induction of Stereotypic behaviour. Treatment with a high dose of cis-flupentixol (0.8 mg) caused a prolonged period of immobility but had no effect on the ingestion of sucrose. Dopamine receptor blockade, therefore, interferes with appetitive, but not consummatory ingestive behaviour. Injection of Cholecystokinin octapeptide (5 μg) suppressed pellet and sucrose intake in a manner comparable to that of apomorphine, but induced no behavioural stereotypes and caused a gradual, rather than inverted U-shaped, increase in the concentration of dopamine in the cerebrospinal fluid that did not correlate with the effect on ingestive behaviour. Furthermore, while the inhibitory effect of apomorphine on the ingestion of sucrose was reversed by pretreatment with a low dose of cis-flupentixol (0.1 mg), the inhibitory effect of Cholecystokinin octapeptide was only partially reversed by cis-flupentixol and a higher dose (0.8 mg) was required. Blockade of cholecystokinin-A receptors, by treatment with L-364,718, but not cholecystokinin-B receptors, by treatment with L-365,260, blocked the inhibitory effect of Cholecystokinin octapeptide and, by itself, L-364,718 increased the amount of ingested sucrose. The inhibitory effect of Cholecystokinin octapeptide on consummatory ingestive behaviour, which is mediated by cholecystokinin-A receptors, is likely to involve mechanisms in addition to dopaminergic ones. 相似文献
43.
To study the possibility that release of dopamine in the brain mediates the inhibitory effect of Cholecystokinin octapeptide on ingestive behaviour, the effect of amphetamine on intake of pellets or an intraorally administered sucrose solution was compared with that of Cholecystokinin octapeptide. Additionally, comparisons were made between the effect of Cholecystokinin octapeptide and pargyline, a monoamine oxidase inhibitor, and α-methyl-ρ-tyrosine, a tyrosine hydroxylase inhibitor. While amphetamine dose-dependently inhibited pellet intake it failed to inhibit sucrose intake in doses which caused behavioural stereotypies (<800 μg). Cholecystokinin octapeptide (5 μg) inhibited ingestive behaviour in both tests. A very high dose of amphetamine (2 mg) was required to inhibit sucrose intake to a level comparable to that of Cholecystokinin octapeptide. Pargyline (5 to 25 mg) or α-methyl-p-tyrosine (25 to 100 mg) dose-dependently inhibited pellet intake but had only weak effects on the intake of sucrose. Pargyline increased the concentration of dopamine and 3-methoxytyramine in the dorsal striatum and decreased the concentration of 3,4-dihydroxyphenylacetic acid. α-Methyl-ρ-tyrosine decreased the concentration of dopamine and 3,4-dihydroxyphenylacetic acid, but not that of 3-methoxytyramine. Injection of amphetamine (2 mg), but not Cholecystokinin octapeptide, in rats pretreated with pargyline increased the concentration of 3-methoxytyramine in the dorsal striatum and this effect was blocked by pretreatment with α-methyl-ρ-tyrosine. Pretreatment with α-methyl-ρ-tyrosine partially reversed the inhibitory effect of Cholecystokinin octapeptide on sucrose ingestion, enhanced the effect of amphetamine but did not affect that of apomorphine, a dopamine agonist. The results support the possibility that the inhibitory effect of Cholecystokinin octapeptide on consummatory ingestive behaviour, in part, is mediated via release of dopamine in the brain. 相似文献
44.
散发内淋巴囊瘤VHL基因位点微卫星标志杂合性丢失的研究 总被引:1,自引:0,他引:1
目的 探讨散发内淋巴囊瘤发病与VHL基因异常之间的关系。方法 采用组织微切割技术和多聚酶链式反应等方法对3例散发内淋巴囊瘤肿瘤细胞VHL基因位点染色体微卫星标志的杂合性丢失进行分析。结果 3例散发内淋巴囊瘤中有2例发生VHL基因位点微卫星标志的杂合性丢失,进一步的研究证实,该两例肿瘤细胞中分别存在着VHL基因第二外显子的异常。结论 VHL基因的异常导致其功能改变不但是VHL的致病原因,而且是散发性内淋巴囊瘤发病的重要的基因遗传学基础。 相似文献
45.
Qureshi AI Luft AR Sharma M Guterman LR Hopkins LN 《Neurosurgery》2000,46(6):1360-75; discussion 1375-6
We reviewed the incidence, risk factors, and clinical features of thromboembolic and ischemic events associated with diagnostic cerebral angiography, endovascular treatment of aneurysms using coils or balloons, angioplasty and stent placement to treat extracranial carotid artery stenosis, and embolization of arteriovenous malformations using glue or other embolic agents. We performed a cumulative analysis to determine the frequency and characteristics of these events and a subset analysis (whenever possible) to determine the benefits of various strategies for complication avoidance. Of the 1,547 patients who underwent Guglielmi detachable coil treatment, thromboembolic events were observed for 127 (8.2%), consisting of asymptomatic events for 12 patients, transient ischemic attacks for 29, and strokes for 86. The outcomes for the 86 patients with strokes were categorized as full recovery for 15, good recovery for 27, partial recovery for 19, no recovery for 11, death for 12, and undetermined outcome for 2. Of the 834 patients who underwent carotid angioplasty and stent placement, thromboembolic events were observed for 73 (8.8%), consisting of transient ischemic attacks for 26 patients and strokes for 47. The outcomes for the patients with strokes were categorized as full recovery for 20, good recovery for 15, partial recovery for 6, no recovery for 2, and death for 4. High rates of thromboembolic events were also observed with balloon occlusion of aneurysms (11%) or parent arteries (19%) and carotid angioplasty alone (5.9%). Arteriovenous malformation embolization was associated with an ischemic event/procedure rate of 9.4%. High rates of thromboembolic and ischemic complications, with subsequent morbidity and death, are associated with most endovascular procedures. Further research and the formulation of standard preventive guidelines may help to reduce these risks and improve the overall success of these procedures. 相似文献
46.
Factors associated with aneurysm size in patients with subarachnoid hemorrhage: effect of smoking and aneurysm location 总被引:2,自引:0,他引:2
OBJECTIVE: Intracranial aneurysm size is an important determinant of risk of rupture and outcome after rupture. Risk factors influencing aneurysm formation and growth are not well defined. In this study, we examined the association between known risk factors for cerebrovascular disease and size of intracranial aneurysms in patients with aneurysmal subarachnoid hemorrhage. METHODS: We analyzed prospectively collected data from the placebo-treated group in a multicenter clinical trial conducted at 54 neurosurgical centers in North America. The presence, location, and size of intracranial aneurysms were determined by review of the admission angiograms. Pertinent information regarding the presence of various cerebrovascular risk factors was collected for each patient. Using logistic regression analysis, we identified independent determinants of aneurysm size from demographic, clinical, and angiographic characteristics of the participants. The impact of aneurysm size on 3-month mortality was analyzed after adjusting for potential confounding factors. RESULTS: For 298 patients admitted with subarachnoid hemorrhage, the ruptured aneurysms were graded as small (<13 mm) in 235 patients (79%) and large (> or =13 mm) in 63 patients (21%). In the logistic regression model, both smoking at any time (odds ratio, 2.2; 95% confidence interval, 1.1-4.5) and middle cerebral artery origin (odds ratio, 2.5; 95% confidence interval, 1.3-4.9) were independently associated with large aneurysms. Neither hypertension, diabetes mellitus, nor alcohol and illicit drug use were associated with large-sized aneurysms. After adjusting for initial Glasgow Coma Scale score and age in the logistic regression model, the presence of large-sized aneurysms was independently associated with 3-month mortality (odds ratio, 2.3; 95% confidence interval, 1.1-4.8). CONCLUSION: Cigarette smoking and middle cerebral artery origin seem to increase the risk for developing large aneurysms in patients predisposed to intracranial aneurysm formation. Further studies are required to investigate the mechanism underlying the association between cigarette smoking and intracranial aneurysm formation. 相似文献
47.
We report a case of secondary psoas abscess in a 37-year-old man with a 3-week history of severe low backache managed conservatively without surgical drainage. Apart from bilaterally restricted straight leg raising (<70 degrees), his neurologic examination was within normal limits. Magnetic resonance imaging showed discitis of the L3-L4 space and a left-sided secondary psoas abscess. Aspiration biopsy of the abscess material under radiologic control isolated Staphylococcus aureus, which responded to appropriate antibiotic therapy with complete resolution. A high index of suspicion is necessary for diagnosis of psoas abscess, which should be considered in patients with pyrexia and backache with a neurologic examination that is otherwise normal. We discuss the recommendations for surgical and nonsurgical approaches. 相似文献
48.
Solitary intestinal fibromatosis (SIF) is very rare; only 9 cases have been described. A new case presenting unusually in a newborn is described and the previously reported cases are reviewed. SIF should be considered in the differential diagnosis of a newborn presenting with an intestinal perforation. 相似文献
49.
BA Evans IA Hughes CL Bevan MN Patterson JW Gregory 《Archives of disease in childhood》1997,76(6):529-531
The androgen insensitivity syndrome is a heterogeneous disorder with a wide spectrum of phenotypic abnormalities, ranging from complete female to ambiguous forms that more closely resemble males. The primary abnormality is a defective androgen receptor protein due to a mutation of the androgen receptor gene. This prevents normal androgen action and thus leads to impaired virilisation. A point mutation of the androgen receptor gene affecting two siblings with partial androgen insensitivity syndrome is described. One had cliteromegaly and labial fusion and was raised as a girl, whereas the other sibling had micropenis and penoscrotal hypospadias and was raised as a boy. Both were shown to have the arginine 840 to cysteine mutation. The phenotypic variation in this family is thus dependent on factors other than abnormalities of the androgen receptor gene alone. 相似文献
50.
Suzanne M. Jacques Faisal Qureshi Barbara J. Doss Adnan Munkarah 《Pediatric and developmental pathology》1998,1(5):380-387
Choriocarcinoma arising in the placenta, or intraplacental choriocarcinoma, has seldom been reported, particularly in the
absence of maternal metastases. Reluctance to diagnose choriocarcinoma in the presence of chorionic villi can delay diagnosis;
however, timely diagnosis of choriocarcinoma is prognostically important, both for the mother and infant. We report the clinicopathologic
findings in five mothers and infants in whom choriocarcinoma was identified in the placenta. None of the mothers had a history
of gestational trophoblastic disease in previous pregnancies. Three placentas were similar with a single small lesion grossly
suggesting a small infarct; microscopically these consisted of infarcted areas surrounded by choriocarcinoma. These three
mothers were unusual in that none had metastatic choriocarcinoma; two were treated with chemotherapy and remained disease-free;
the third was lost to follow-up shortly following delivery. The remaining two mothers had known pulmonary metastases at time
of delivery. One of these latter two placentas contained a large marginal lesion microscopically identified as choriocarcinoma.
The fifth placenta had rare microscopic foci of choriocarcinoma, and sheets of necrotic choriocarcinoma were identified in
“blood clot” submitted with the placenta. In four of the five cases the choriocarcinoma appeared to be arising from otherwise
normal chorionic villi, and in no case was there invasion of the villous stroma. All of the infants survived, and none had
evidence of choriocarcinoma. These cases support the concept that choriocarcinoma associated with otherwise normal pregnancy
arises in the placenta and may be more common than reported.
Received August 11, 1997; accepted December 8, 1997. 相似文献