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91.
We performed suprapubic percutaneous urography in two patients to diagnose unusual duplication anomalies of the urinary tract, since preoperative diagnosis was unclear after routine noninvasive studies. In both patients standard suprapubic puncture technique was employed. The procedure was used to confirm the diagnosis of duplication of the bladder in one case and to establish the site of origin of a ureterocele in the other. The technique employed in suprapubic cystography may be extended to the diagnosis of unusual cystic abnormalities in the pelvis that may be of urinary tract origin. 相似文献
92.
This paper describes the results of the application of linear solvation energy relationships (LSERs) to quantitatively characterize the properties of adhesives and to evaluate the degree of drug-adhesive interaction in transdermal drug delivery formulations. Probe solutions were prepared in acetonitrile (ACN) for a set of probe compounds with different physicochemical properties, and were used to swell the adhesives for subsequent probe molecule-adhesive interactions. The degree of the interactions was measured by the 'sorbed' amount of probe molecules. Based on LSERs, the 'sorbed' amounts were linearly correlated with their properties. The corresponding coefficients reflect the differential interactions of these molecules with the adhesive and ACN, and are quantitative indications of the adhesive properties. Two different transdermal acrylate adhesives (isooctyl acrylate/acrylamide/vinyl acetate in the weight ratios of 75/5/20 and isooctyl acrylate/2-hydroxyethyl acrylate/vinyl acetate in the weight ratios of 58/20/18) were selected for the evaluation of the methodology. It is concluded that the first adhesive is more basic and hydrophobic, which is consistent with the use of acrylamide monomer and significant amount of isooctyl acrylate. The second adhesive is more acidic and polarizable due to a relatively high amount of the 2-hydroxyethyl acrylate. Additionally, the 'sorbed' amount can be regarded as an interaction parameter or index between a drug molecule and the adhesive. Finally, this parameter is expected to correlate with the thermodynamic properties of transdermal formulations such as drug solubility, diffusion coefficient, release rate, and maybe skin permeation rate. 相似文献
93.
A. W. Logue Henry Tobin John J. Chelonis Rex Y. Wang Nori Geary Stanley Schachter 《Psychopharmacology》1992,109(1-2):245-247
Cocaine abuse is often associated with behavior that takes into account short-term, but not long-term consequences. However, there has been no empirical research concerning the effects of cocaine on self-control (choice of a larger, more delayed reinforcer over a smaller, less delayed reinforcer). In the present research, when food-deprived rats repeatedly chose between a larger, more delayed food reinforcer and a smaller, less delayed food reinforcer, chronic intraperitoneal injections of 15 mg/kg cocaine (but not 10 mg/kg fluoxetine) decreased the rats' choices of the larger, more delayed reinforcer. Cocaine can decrease rats' self-control. 相似文献
94.
Familial and sporadic hyperinsulinism: histopathologic findings and segregation analysis support a single autosomal recessive disorder 总被引:4,自引:0,他引:4
P S Thornton A E Sumner E D Ruchelli R S Spielman L Baker C A Stanley 《The Journal of pediatrics》1991,119(5):721-724
We evaluated the possible genetic contribution to hyperinsulinism in a series of patients seen during the past 15 years. Of 26 families, 5 (19%) had more than one child affected (multiplex family). There were no apparent differences between patients in the 5 multiplex and 21 simplex families, clinically, biochemically, or on histologic examination of the pancreatic specimens. The families studied had a total of 63 offspring; the 26 index patients had 37 siblings, 6 of whom were affected. After four patients with hyperinsulinism caused by adenoma were excluded from the study, segregation analysis was carried out to test the data for agreement with results expected if familial and isolated hyperinsulinism represented a single disease with recessive mode of inheritance and a segregation ratio of 0.25. Excellent agreement was found between the observed number of affected siblings (20) and the expected number (19.65), with a segregation ratio of 0.254. The results were consistent with the hypothesis that in most or all cases, hyperinsulinism is inherited as an autosomal recessive disease. There was no evidence of distinct familial and sporadic types. 相似文献
95.
D Block S Cruikshank K Kelly M Stanley 《International journal of gynaecology and obstetrics》1991,34(4):377-380
The rare teratoma of the placenta has been compared to the fetus amorphus, two distinguishing characteristics being the teratoma's lack of structural organization and lack of large vessels entering the tumor. A case of placental teratoma and theories of origin are discussed. 相似文献
96.
Brain tissue oxygenation in patients with cerebral occlusive disease and arteriovenous malformations
Hoffman W. E.; Charbel F. T.; Edelman G.; Ausman J. I. 《British journal of anaesthesia》1997,78(2):169-171
It is not clear if ventilation with oxygen increases brain tissue oxygen
pressure (PO2) during ischaemia. We have measured brain tissue PO2, carbon
dioxide pressure (PCO2) and pH during baseline anaesthesia and oxygen
ventilation in non-ischaemic control patients (n = 9), patients with
cerebral occlusive disease (n = 11) and patients with arteriovenous
malformations (AVM, n = 12). The same anaesthetic treatment was given to
all groups and anaesthesia was constant during the study. Arterial
pressure, brain temperature and arterial blood-gas tensions were similar
between groups. Under baseline conditions, brain tissue PO2 was mean 4.2
(SD 1.4) kPa in the controls and was 70% lower in patients with ischaemia
and AVM. Patients with occlusive disease also had elevated tissue PCO2 and
acidosis. During oxygen ventilation, PO2 increased to 7.5 (2.9) kPa in
controls and this was 50% greater than the increase in the ischaemia and
AVM patients. The results showed that baseline tissue oxygenation and
increases in PO2 during hyperoxia were attenuated in patients with
ischaemia or AVM.
相似文献
97.
98.
Stanley J. Szefler Alan K. Kamada Donna Hughes A. Manon Brenner Erwin W. Gelfand 《The Journal of asthma》1992,29(2):91-97
Alternative treatments such as troleandomycin methotrexate, gold, and intravenous gamma globulin are sometimes considered for severe asthmatics to minimize the need for systemic corticosteroids and reduce adverse effects. These alternative therapies may also be associated with significant toxicity and expense. The ability to reduce corticosteroid use and the need for alternative treatment interventions in 125 pediatric patients at our institution were reviewed. Because corticosteroid requirements were reduced significantly, only 23 of 125 children evaluated were considered for treatment alternatives with only 10 receiving such therapy. This study emphasizes the importance of a thorough and comprehensive review of corticosteroid requirements and usage prior to initiating alternative approaches to treatment in moderate to severe asthmatics as well as in patients thought to be “steroid-dependent.” 相似文献
99.
100.
Fernando Cendes Jeff A. Stanley FranOis Dubeau Frederick Andermann Douglas L. Arnold 《Annals of neurology》1997,41(1):74-81
We performed proton magnetic resonance spectroscopic imaging of the temporal lobes between, during, and soon after nonconvulsive seizures in 20 patients with documented temporal lobe epilepsy, 5 patients with primary generalized epilepsy, and 2 patients with secondary generalized epilepsy. Our objective was to determine whether there were metabolic changes observable by magnetic resonance spectroscopic imaging during seizures and whether these changes were specific for focal or generalized nonconvulsive seizures. We found a significant increase in lactate to creatine plus phosphocreatine (lactate/creatine) values, reflecting an imbalance in energy supply and demand or an adaptation in response to ictal neuronal discharges, during and soon after complex partial seizures, but not during or soon after absence seizures associated with generalized epilepsy. In patients with temporal lobe epilepsy, the N-acetylaspartate resonance relative to creatine plus phosphocreatine was low in one or both temporal lobes, indicating neuronal loss or damage. This was not observed in patients with primary generalized epilepsy. The regions with abnormal lactate/creatine and N-acetylaspartate/creatine values corresponded to the epileptogenic focus as defined by clinical-electroencephalographic investigation. There was no change in the N-acetylaspartate/creatine values in the temporal lobes between the interictal, ictal, or postictal states. We conclude that (1) partial seizures are associated with abnormally high lactate levels, but absence seizures are not, and (2) no short-term changes of N-acetylaspartate occur during or soon after complex partial seizures or absence seizures. These findings may be related to the lack of postictal confusion in patients with absence seizures, as well as with the more benign course of primary generalized epilepsy with nonconvulsive attacks. 相似文献