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1.
Background: Xenon is an odorless gas with low blood-gas solubility coefficient and without occupational and environmental hazards. This investigation was performed to evaluate the speed of induction, and respiratory and cardiovascular reactions to inhalation induction with xenon compared to an equianesthetic concentration of sevoflurane.
Results: Compared to equianesthetic sevoflurane, xenon produced a faster induction of anesthesia (14759 versus 71221 s, respectively) with smaller decreases in respiratory rate, tidal volume and minute ventilation. Both agents showed comparable cardiovascular stability and oxygen saturation during induction. One patient in the sevoflurane group had breath-holding and movements of extremities and another had only breath-holding. No patients in the xenon group experienced any complications.
Conclusion: Xenon produced a faster induction of anesthesia without any complications than sevoflurane. Xenon had smaller decreases in tidal volume and respiratory rate during induction than sevoflurane. Xenon might offer an alternative to sevoflurane for an inhalation induction.
Method Twenty-four adult ASA 1–2 patients premedicated with 0.05 mg/kg of midazolam were instructed to take vital capacity breaths of 1 minimum alveolar concentration (MAC) of either xenon or sevoflurane until they lost consciousness. Induction time, total ventilatory volume, tidal volume, respiratory rate, minute ventilation, end-tidal MAC fraction, cardiovascular parameters and oxygen saturation were recorded. The patients were interviewed on the following day to evaluate their acceptability rating of the inhalation inductions.  相似文献   
2.
Little work has been done with positive emission tomography (PET) in bladder tumors because high urinary excretion of (18)F-FDG makes visualization of the bladder tumor difficult. (11)C-choline has recently been reported as a new tracer which lacks urinary radioactivity. We report the result of (11)C-choline PET in four patients with invasive bladder tumors. In one case, (11)C-choline PET could detect bladder tumor effectively without urinary activity and bone metastasis despite negative bone scintigraphy. On the other hand, an intense accumulation of the tracer in the bladder hampered the interpretation on PET scanning in three patients. The mechanisms of the (11)C-choline accumulation in the bladder were reported to be due to inflammatory and proliferative changes in the mucosa of the bladder from previous catheterization or other factors. Further study is necessary to prove the value of (11)C-choline PET for detecting primary bladder cancer and bone metastasis.  相似文献   
3.
A case of malignant haemangioendothelioma of the scalp in an 82-year-old female treated with intralesional, intra-arterial and intravenous recombinant interleukin-2 (rIL-2) is reported. The scalp lesions disappeared after injection of 35 350 000 Japan reference units of rIL-2 and excision of the residual tumour. Immunohistochemical characterization of the cells infiltrating the lesion after rIL-2 administration revealed 30–40% CD4+ and CD8+ T lymphocytes, 20–30% macrophages and 5–10% natural killer cells. These findings are similar to those in other human cancers. Almost all of the cells in the intersticies of the lesion after rIL-2 injection expressed leucocyte function-associated antigen-1, and some of the tumour cells and the infiltrating cells around them expressed intercellular adhesion molecule-1. HLA-DR-positive cells markedly increased in number after rIL-2 administration. This report suggests that rIL-2 administration is the most effective therapy for malignant haemangioendothelioma.  相似文献   
4.
To clarify the significance of basic fetoprotein (BFP) in lymphocytes, we investigated whether BFP is produced in lymphocytes during blastic transformation. Peripheral blood lymphocytes obtained from 14 adults were cultured under the stimulation of lectins. The concentration of BFP in the culture medium (extracellular BFP) was estimated serially. The incorporation of [6-3 H] thymidine was assayed simultaneously. The intracellular BFP was measured by dual flow cytometry for DNA and BFP. A lymph node was studies immunohistochemically. Serum BFP was measured in four cases of lumphocytic leukaemia. In two cases, dual staining was performed. The intracellular BFP of the mitogen-stimulated lymphocytes was increased within 24 h. The extracellular BFP was increased exponentially from 72 h. The extracellular BFP at 96 h did not correlate with the [3H]-thymidine incorporation. The intracellular BFP increase began in G1 phase. Immunostaining showed that the B cells also produced BFP. The
serum BFP level in leukaemia was high in 1 of 4 cases and the leukaemic cells in two cases showed high intracellular BFP content. These observations indicate that BFP is produced in activated human lymphocytes and in lymphocytic leukaemic cells. The production of BFP during blastic transformation will be a useful new in vitro model for studying the biological role of BFP, and BFP labelling may offer some new possibilities for study of lymphocytes.  相似文献   
5.
The metabolic behavior, clearance, and pulmonary effects ofgadolinium (Gd), one of the rare earth elements, were investigatedafter single intratracheal instillation of gadolinium chloride(GdCl3) in male Wistar rats. There was a dose-related increasein Gd content of lung tissue. Gd content in the supernatantof bronchoalveolar lavage fluid (BALF) did not exceed 5 µgGd/ BALF even at a dose of 100 µg Gd/rat. Gd in the lungtissue decreased very slowly with a biological half-life of136 days at a dose of 50 µg Gd/rat. On the other hand,Gd content in the super natant of BALF was not detectable after31 days. These results suggest that intratracheally instilledGd can be retained in epithelial lining fluid only to a limitedextent as soluble forms and is deposited in the lung tissueprobably in insoluble forms which are metabolized very slowly.Calcium (Ca) content in BALF increased more rapidly than othertoxicological indices such as lactate dehydrogenase activity,protein concentration, and inflammatory cell counts. In thelung tissue, levels of Ca in Gd-instilled groups did not differfrom the control value. Although these data suggest that theorigin of Ca may be blood plasma, biological and/or toxicologicalsignificance of increased Ca is not known. The number of neutrophilsreached the maximum at 12 hr after instillation, indicatingthat Gd has the potency to cause acute lung toxicity. Summarizingthe observation, Gd instilled intratracheally into rats wasdeposited in the lung tissue in nonsoluble forms with an extremelylong half-life, while the metal caused a rapid and selectiveinfiltration of serum Ca before acute lung toxicity.  相似文献   
6.
Thirteen patients with gastric metastasis were examined endoscopicallyand their diseases were diagnosed histologically at the NationalCancer Center Hospital from 1962 to 1980. Their endoscopic findings were analyzed. The metastatic lesionwas solitary in 10 of the 13 cases and multiple (9 lesions)in three. Although 12 of the 13 cases showed elevated lesionsendoscopically, ulcerated hemispherical nodules, which correspondto the "bull's-eye sign" of Pomerantz roentgeno-graphically,were observed in only four cases. In the remaining nine casesthe endoscopic findings were submucosal tumor without centraldepression (2 cases), a cancer-like appearance (6 cases) orextragastric compression (1 case). The majority of these metastatic lesions (9 of the 19; 47.3%)were located along the greater curvature of the stomach. Fromthese results, the elevated lesion of the greater curvaturemight suggest a metastatic tumor regardless of the conventionalcriteria (multiplicity or ulcerated hemispherical nodule) whenthe patient has cancer in other organs.  相似文献   
7.
To evaluate the endoscopic criteria for early malignant findingsof gastric carcinoma more precisely, a retrospective examinationof endoscopic pictures of 72 patients with gastric carcinomawas carried out. The patients had received endoscopic examinationsrepeatedly for years and proceeded finally to surgery on thebasis of a diagnosis of carcinoma by gastric biopsy. The macroscopicas well as microscopic findings of the resected specimens werecompared with the previous endoscopic observations. Ulcerative lesions were predominantly found at the initial endoscopyin patients whose final diagnosis was the lie type of earlygastric cancer or IIc-like advanced cancer. These patients usuallyreceived endoscopic examinations repeatedly and their lesionswere diagnosed as malignant by the adopted criteria of earlygastric cancer 2 to 6 yr after the initial examination. In contrast, nonulcerative lesions were observed more frequentlyat the initial examination in patients with the final diagnosisof the IIa+IIc type of early gastric cancer or Borrmann typeof advanced cancer. In most of those patients endoscopic examinationwas not carried out so frequently, and in some of those whohad been closely followed the malignant findings appeared rathersuddenly with tumorous formation as well as deeper invasionduring less than a few years from the previous examination atwhich the tumor had been considered benign. These data indicate that the nonulcerative lesions which wereconsidered benign could be the early expression of gastric carcinoma.It should be stressed that nonulcerative lesions such as "irregularerythematous change, discoloration, flat granular change" and"simple mucosal depression" observed in some parts of the stomachwould be important site for the detection of early gastric carcinoma,and that these lesions need to be biopsied more frequently.  相似文献   
8.
We conducted molecular analysis of two candidate genes for spinal muscular atrophy (SMA), the survival motor neuron gene (SMN) and the neuronal apoptosis inhibitory protein gene (NAIP), in 16 Japanese patients with SMA and compared the phenotypic features of SMA in these patients with the corresponding genotypes. Exons 7 and/or 8 of SMN were homozygously deleted in 11 SMA type I (Werdnig-Hoffmann disease) patients, two SMA type II patients and one SMA type III patient. Exons 5 and 6 of NAIP were homozygously deleted in six SMA type I patients. No patient had a deletion in NAIP without a deletion in SMN. Mechanical ventilation was required during the first 7 months of life in the SMA type I patients who had a deletion in both SMN and NAIP. Ventilatory support was initiated within 2 years after birth in patients who had a deletion in SMN but not in NAIP. We detected homozygous deletion of exon 5 of NAIP in the unaffected mothers of two SMA type I patients. In these families, the patients exhibited a deletion in both SMN and NAIP. The parents and unaffected siblings of these patients did not have a deletion in SMN. The present findings support the hypothesis that SMN deletion plays an important role in the development of SMA and suggest that combined deletion of both SMN and NAIP may be relevant for determining the disease severity.  相似文献   
9.
Phenotypic changes in lymphocytes from healthy children with antibody for human T lymphotrophic virus type I (HTLV-I) were studied using two color flow cytometry. The subjects were high school students within a small district of Kyushu, Japan. In the carrier group, a subset of lymphocytes which expressed CD8+CD57+ was significantly lower in percentage (P < 0.01) and in number (P < 0.05). There was no significant difference between carriers and non-carriers in the percentage and number of CD4+ Leu8+cells or CD4+ HLA-DR+ cells. The IgG levels were slightly higher in carriers than in non-carriers (P < 0.05). These findings suggest that HTLV-I-infected cells may affect the immune system in healthy carrier children.  相似文献   
10.
We report a case of ureteral obstruction due to retroperitoneal fibrosis secondary to a solitary left internal iliac aneurysm. It has been reported that as a cause of ureteral obstruction, an internal iliac aneurysm without aortic and/or common iliac aneurysms is very rare. In the present case, magnetic resonance imaging was a useful modality to diagnose retroperitoneal fibrosis secondary to an internal iliac aneurysm as a direct cause of ureteral obstruction.  相似文献   
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