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131.
132.
Hemorrhagic intracranial malignant neoplasms: spin-echo MR imaging   总被引:2,自引:0,他引:2  
Twelve patients with 15 separate, spontaneously hemorrhagic, intracranial malignant lesions (seven primary gliomas, eight metastatic lesions) were examined with spin-echo magnetic resonance imaging at 1.5 T, and with computed tomography. The signal intensity patterns of these lesions, as seen on both short repetition time (TR)/short echo time (TE) and long-TR/long-TE spin-echo pulse sequences, were compared with the previously described appearance at 1.5 T of non-neoplastic intracerebral hematomas. The images of hemorrhagic intracranial malignancies showed notable signal heterogeneity, often with identifiable nonhemorrhagic tissue corresponding to tumor; diminished, irregular, or absent hemosiderin deposition; delayed hematoma evolution; and pronounced or persistent edema, compared with non-neoplastic hematomas. The demonstration of these characteristics in the appropriate clinical setting may suggest malignancy as the cause of an intracranial hematoma.  相似文献   
133.
Phosphorus-31 magnetic resonance (MR) spectroscopy was used to study the effects of partial and complete ureteral obstruction on the porcine kidney; results were compared with renal tubular function as determined with technetium-99m dimercaptosuccinic acid (DMSA) scintigraphy. Twenty-seven pigs were used: nine as sham-operated controls, six with partial ureteral obstruction, and 12 with complete ureteral obstruction. P-31 MR spectra and Tc-DMSA scintiscans were obtained weekly over 3 weeks. Partial obstruction caused no significant change in P-31 MR spectra, whereas Tc-DMSA scintiscans showed a 74% decrease in tubular function by the end of 3 weeks. Complete obstruction caused a 43% reduction in the mean adenosine triphosphate (ATP) to inorganic phosphate (Pi) ratio, which paralleled the 96% decrease in Tc-DMSA uptake over 3 weeks. The difference in ATP/Pi ratios between control and completely obstructed kidneys was significant (P less than .01) at 2 and 3 weeks after ligation. These results indicate that radionuclide Tc-99m DMSA uptake is very sensitive to the pathophysiologic changes in renal tubular function, while the organ average cellular bioenergetic state (ATP/Pi) is not as strongly affected.  相似文献   
134.
Liebhaber  SA; Cash  FE; Cornfield  DB 《Blood》1988,71(2):502-504
The level of Hb C in the erythrocytes of individuals with Hb C trait decreases significantly in the presence of coexisting alpha- thalassemia. This relationship may result from the higher affinity of beta A than beta C for limiting amounts of alpha-globin during hemoglobin assembly. This mechanism would predict that the beta A and beta C synthetic capacity in alpha-thalassemic individuals with Hb C trait should be balanced despite the low levels of Hb C in their circulating erythrocytes. To directly test this prediction, we have measured the beta A and beta C synthetic capacity of reticulocyte RNA isolated from two individuals with Hb C trait, one with a normal alpha- globin genotype and one with alpha-thalassemia. The balanced expression of beta A and beta C in both cases supports the proposed posttranslational control over Hb C expression.  相似文献   
135.
Suriclone is a new anxiolytic drug belonging to the family of cyclopyrrolones. The effects of acute and repeated doses of suriclone on subjective sleep, psychomotor performance and cognitive function were compared to those of placebo in young and elderly volunteers. Young volunteers randomly received suriclone 0.2 mg, 0.3 mg, 0.4 mg or placebo tid, and the elderly received suriclone 0.1 mg, 0.2 mg or placebo tid. After the first single dose and after a three-day treatment, subjects completed at 1, 2, 4, 12 and 24 h after drug administration the following battery of psychomotor and cognitive tests: critical flicker fusion threshold, choice reaction time, simulated car tracking test, the stroop test and the Sternberg memory scanning task. Visual analogue scales and the Leeds sleep evaluation questionnaire were also administered during the study. No significant effects of suriclone compared to placebo were seen on the psychomotor tests both in young and elderly volunteers. The only significant result was an improvement of the ease of getting to sleep in the young with 0.4 mg suriclone tid. In conclusion, there is little evidence to suggest that suriclone produces any measurable behavioural toxicity, so often seen with many of the benzodiazepines, in either young or elderly subjects.  相似文献   
136.
BACKGROUND: The technique of allele-specific polymerase chain reaction (PCR) amplification has been adapted for DNA-based human platelet alloantigen typing. STUDY DESIGN AND METHODS: Sequence-specific primers were used to discriminate between the alleles encoding the six major human platelet alloantigens in a series of patients and normal blood donors. RESULTS: This technique allows the direct determination of platelet antigen genotypes from genomic DNA after PCR amplification and agarose gel electrophoresis. It offers significant advantages over previously described techniques for alloantigen identification, as the additional analytical steps of restriction enzyme digestion or dot blot hybridization are not required. The results obtained with this technique correlated precisely with those derived from serologic typing and allele-specific oligonucleotide hybridization. CONCLUSION: The use of allele-specific PCR for platelet alloantigen typing should facilitate the development of DNA-based typing in other regional blood centers and clinical laboratories.  相似文献   
137.
A total of 355 outpatients and 73 inpatients were studied for cerebrovascular disease with intraarterial digital subtraction angiography (DSA). The studies were performed by means of selective carotid and vertebral artery catheterization from a transbrachial approach. Selective catheterization of the carotid artery was possible in 95% of patients, with definitive examinations of both extra- and intracranial circulation obtained in 95%-100% of all patients. Vessel opacification was very good to excellent, and the technique was inherently free from artifact caused by vessel overlap or involuntary motion. There were 25 complications, of which 20 were local in nature. Iodine load per case was extremely low, averaging 4.2-7.0 g. Selective carotid and vertebral catheterizations by the brachial route proved to be as safe as intravenous DSA and aortic arch intraarterial DSA with less contrast material load and superior images.  相似文献   
138.
139.
伊贝辛的分离和鉴定   总被引:3,自引:0,他引:3  
从吉林栽培的伊贝母(Fritillaria pallidiflora Schrenk)鳞茎中分离出两种介藜芦胺类生物碱Ⅰ和Ⅱ。碱Ⅱ是一个新的甾体生物碱,定名为伊贝辛(yibeissine),结构为22,26-imino-17,23-oxidojerv-12-en-6-oxo-3β,11α-diol,碱Ⅰ是一个已知化合物,结构为11-deoxo-6-oxo-5α,6-dihydrojervine。  相似文献   
140.
Liver metastases of colorectal cancer is present in more than 20% of new diagnosed patients and in 40–60% of relapsed patients. It is a life-threatening prognostic aspect. Hepatic resection, when possible, is the best therapeutic modality, although the overall survival rate is still low (30%). Angiography and intraoperative ultrasonography are useful for resection. The number of hepatic metastases and the surgical margin are probably the most significant prognostic factors. Colorectal cancer may spread predominantly to the liver making regional treatment strategies viable options. Subtotal hepatic resections and segmentectomies are potentially curable procedures for single or small numbers of hepatic metastases without other sites of disease. However, there have been no prospective randomized trials comparing patients with unresected liver metastases and resected metastases. Regional chemotherapy with floxuridine seems usefull combined with hepatic resection or as palliative therapy. Gastric ulcer and biliary sclerosis are the main related toxicities. Patients with localized, unresectable hepatic metastases or concomitant bad medical condition may be candidates for radiation, percutaneous ethanol injection, cryosurgery, percutaneous radiofrequency, hypoxic flow-stop perfusions with bioreductive alkylating agents, hepatic arterial ligation, embolization and chemoembolization. These new hepatic-directed modalities of treatment are being investigated and may offer new approaches to providing palliation and prolonging survival. This review will report the possibilities of intra-arterial chemotherapy and other novel hepatic-directed approaches to the treatment of liver metastases from colorectal cancer.  相似文献   
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