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61.
Percutaneous transfemoral arterial balloon occlusion or gelatin sponge embolization of the splenic artery or both were carried out in three high-risk patients with hepatic cirrhosis to reduce splenic hyperfunction and improve severe thrombocytopenia. Although this maneuver raised peripheral platelet counts in each patient, in one patient left upper quadrant pain with splinting of the lower chest cage led to hypostatic lower lobe pneumonia, while in another septic splentitis with gas-forming organisms necessitated splecectomy. Transfemoral occlusion of the splenic artery, although an effective, noninvasive approach to control splenic hyperfunction, has at the same time potential dangers that should be viewed with extreme caution in therapeutic application.  相似文献   
62.
In a cytogenetic study on the spermatogonia of Chinese hamster, cyclohexylamine (neutral sulphate) was evaluated for mutagenic effects in comparison with an untreated control group and a group treated with the mutagenic compound cyclophosphamide, by assessing spermatogonial metaphases of treated Chinese hamster for chromosomal structural changes. Each test group comprised 8 male hamsters selected at random. Approximately 100 metaphases from each animal were assessed. The doses were 5 X 150 mg cyclohexylamine sulphate (approx. 5 X 102 mg base) per kg body-weight orally, and 5 X 100 mg cyclophosphamide per kg body-weight orally. The individual doses were administered at intervals of 24 h. Preparations were made 24 h after the final treatment, essentially by the method of Hoo and Bowles [10]. Gaps, breaks, fragments, deletions and translocations were assessed as structural changes; frequencies were determined of the metaphases (a) with aberration(s) including gaps, (b)with aberration(s) less gaps and (c)with translocation(s). Aberrations occurred in the untreated negative control group (1.24% incl. gaps, 0.25% without gaps). Translocations were not seen in the untreated group. In the cyclochexylamine group, the frequencies of the aberrant metaphases were sometimes less than in the control group (0.87% including gaps, 0.37% without gaps). Statistically, the results were not significantly different from the control data. No translocations were seen after administration of cyclohexylamine. The positive cyclophosphamide control group clearly differed from the untreated control and from the cyclohexylamine group in the parameters (a) to (c); mainly, the results were highly significantly different from those obtained in the untreated control group. The frequencies of the aberrant metaphases were 3.41% including gaps and 1.99% without gaps. The frequency of the translocations was 0.71% (5 out of 704). Cyclohexylamine sulphate, administered 5 times at 150 mg/kg body-weight orally, had no mutagenic effect, whereas cyclophosphamide, adminstered 5 times at 100 mg/kg body-weight orally, had a chromosome-damaging effect on Chinese hamster spermatogonia.  相似文献   
63.
In order to compare the venodilation effect of morphine in normal individuals (22) with that in patients (13) with heart failure morphine sulfate (0.1 mg/kg) was administered to 13 patients with mild pulmonary edema. After morphine congestive symptoms improved and venodilation was induced as determined by two independent techniques: venous pressure fell 10.2 mm Hg by the isolated hand technique and the venous volume of the forearm increased by 0.48 cc/100 ml, measured by equilibration technique. Neither finding differed from those in normal individuals. Reflex venoconstriction noted on the taking of a single deep breath was unaffected by morphine administration and was similar to that observed in normal subjects. Since the drug morphine sulfate does not cause a major pooling of blood in the limbs, the favorable effect of narcotics in patients with pulmonary edema must be caused by other mechanisms such as splanchnic pooling, afterload reduction or reduced breathing effort.  相似文献   
64.
Over a ten-year period, 129 patients with idiopathic pelviureteric obstruction were randomly selected for splinted or unsplinted pyeloplasties. Of these groups, the patients with splinted pyeloplasties had a lower incidence of postoperative complications. The long-term results were similar in both groups.  相似文献   
65.
In head injured patients changes were found in the CSF levels of metabolites of the dopaminergic and the serotonergic neurotransmission (HVA and 5-HIAA). After the fifth day following trauma a significant decrease of the HVA levels in the lumbar CSF after probenecid treatment was found. The intensity of this decrease was found to be related to the severity of the trauma (period of unconsciousness), but not to the state of consciousness. Also the probenecid-induced 5-HIAA levels in conscious patients were decreased after the fifth post-traumatic day. In unconscious patients, the period of unconsciousness, particularly in the period of 5-20 days after trauma. Between 21 and 60 days after trauma the 5-HIAA concentrations in unconscious patients decreased remarkably, but they were still significantly higher than in the conscious patients. It can be concluded that during unconsciousness serotonergic neurons have a high rate of turnover, but that both neurotransmitter systems are damaged by the direct or indirect consequences of the injury.  相似文献   
66.
A case of primary retroperitoneal germinoma is presented in which markedly elevated serum lactic dehydrogenase levels were present before diagnosis, but declined to normal with abdominal irradiation. It is the first report of lactic dehydrogenase serving as a tumor marker in germinoma.  相似文献   
67.
The in situ microbiota from several aquaculture facilities with active nitrification was examined by transmission electron microscopy of thin sections for the presence of bacteria that contained intracytoplasmic membranes characteristic of the nitrifying bacteria. Colonies of bacteria with the cellular morphology of a species of Nitrosomonas were found to be present in both the culture water and in the biological filter slime of a freshwater chinook salmon (Oncorhynchus tshawytscha) culture system. bacteria in the water possessed the normal nitrosomonas type of ultrastructure, whereas similar bacteria in the slime had an aberrant morphology due to multiple invaginations of the cell wall and cyto-membranes and a significantly greater number of ribosomes. These nitrosomonas-like bacteria lysed during enrichment in commonly used media. Bacteria with the morphology of species of Nitrosomonas and Nitrosococcus were also observed in colonies in the surface slimes of marine culture systems for striped bass (Morone saxatilis) and quahaug (Mercenaria mercenaria).  相似文献   
68.
The per review system for the assessment of research proposals is widely respected by working scientists. Nevertheless two problems associated with the operation of this system by the US National Institutes of Health are identified. First the scientist has no control over which committee will review an application and it may be considered by a quite inappropriate group. Second analysis of the committee composition suggests that in some of the groups several members are not active scientists and therefore not the "peers" of the applicant.  相似文献   
69.
The bioluminescent reaction of adenosine 5'-triphosphate (ATP) with luciferin and luciferase has been used in conjunction with a sensitive photometer (Lab-Line's ATP photometer) to detect significant bacteriuria in urine. This rapid method of screening urine specimens for bacteriuria was evaluated by using 348 urine specimens submitted to the clinical microbiology laboratory at the University of Minnesota Hospitals for routine culture using the calibrated loop-streak plate method. There was 89.4% agreement between the culture method and the ATP assay, with 7.0% false positive and 27.0% false negative results from the ATP assay using 10(5) organisms/ml of urine or greater as positive for significant bacteriuria and less than 10(5) organisms/ml as negative for significant bacteriuria.  相似文献   
70.
Sequential ascending venographic studies were used to assess the healing of deep venous thrombosis in 50 patients randomly assigned to streptokinase or heparin therapy. Various degrees of thrombolysis and/or recanalization were demonstrated by venograms performed on the fourth and tenth days of treatment. Late follow-up studies (mean, 7 months after treatment) showed three basic patterns of resolution: (1) return to normal, (2) complete recanalization, and (3) incomplete recanalization and/or collateralization. Loss of valves or their function was associated with recanalization. The character, speed, and outcome of healing reflected the nature and extent of thrombosis, prior thrombotic disease in the extremity, and the type and timing of treatment. Streptokinase was highly effective and preferable to heparin in patients with deep vein thrombosis when therapy was begun within 4 days of onset of symptoms. In later stages of acute or recurrent deep vein thrombosis, the effectiveness of both drugs was significantly reduced.  相似文献   
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