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11.
Experience with the new Olympus twin channel TCF-2L colonoscope is presented. Based on 60 examinations including 25 polypectomies it is concluded that the instrument when compared with other colonoscopes is easier to handle and its advancement within the colon is faster, smoother and therefore less disagreeable to the patient. The proximal colon is easier to reach than previously experienced. Polypectomy and retrieving of polyps can efficiently be undertaken. This instrument will undoubtedly further enhance the usefulness and therapeutic value of fibre colonoscopy.  相似文献   
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The purpose of the study reported here was to investigate the impact of prophylaxis against gram-positive infections in patients undergoing high-dose chemotherapy and autologous bone marrow transplantation in a randomized trial. Forty-three patients undergoing high-dose chemotherapy with autologous bone marrow transplant were enrolled in a nonblinded randomized trial to receive or not to receive prophylaxis for gram-positive infections with 10(6) U of penicillin intravenously (i.v.) every 6 h (q6h) (if penicillin allergic, 750 mg of vancomycin i.v. q12h) in addition to standard antimicrobial prophylaxis with 400 mg of norfloxacin orally three times a day, 200 mg of fluconazole orally once a day, and 5 mg of acyclovir per kg of body weight i.v. q12h. The patients were being treated for germ cell cancer (n = 15), breast cancer (n = 16), Hodgkin's disease (n = 3), non-Hodgkin's lymphoma (n = 4), acute myeloid leukemia (n = 1), acute lymphoblastic leukemia (n = 1), and ovarian cancer (n = 3). The trial was stopped because of excess morbidity in the form of streptococcal septic shock in the group not receiving gram-positive prophylaxis. There were significantly fewer overall infections (10 versus 3; P = 0.016) and streptococcal infections (9 versus 1; P = 0.0078) in the group receiving gram-positive prophylaxis. There were no significant differences in the numbers of deaths, duration of broad-spectrum antibiotics, or incidence of neutropenic fever between the two groups. Prophylaxis for gram-positive infections with penicillin or vancomycin is effective in reducing the incidence of streptococcal infections in patients undergoing high-dose chemotherapy and autologous bone marrow transplant. However, this approach may carry a risk of fostering resistance among streptococci to penicillin or vancomycin.  相似文献   
14.
The Honeywell ACS 1000 is a relatively inexpensive differential white cell counter, which is only partially automated. This instrument has been evaluated in a routine haematology laboratory.  相似文献   
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We reviewed 395 patients with isolated hemo- or hemopneumothorax from stab or bullet wounds. Of these, 45 were in shock on admission. All patients were initially treated by closed thoracostomy and infusions or transfusions. Of the 45 patients in shock, 24 responded to this treatment and remained stable. The other 21, after an initial response, showed a renewed drop in blood pressure and rise in pulse rate and had to be explored. All were found to be bleeding from either a systemic artery or a major lung laceration extending into the hilus. All other patients were continued on tube drainage, supplemented, if necessary, by needle aspiration and instillation of fibrinolytic enzymes until the lung was fully expanded, thus avoiding empyemas and the need for decortications. We found the clinical course after initial tube thoracostomy to be a reliable indicator for thoracotomy or for continued non-operative management, thus avoiding unnecessary thoracotomies.  相似文献   
17.
We propose a method of using a relatively low degree of freedom (DOF) warping to accurately measure the interval change of lesions having homogeneous contrast. The setting presented here presupposes the use of interval computed tomography (CT) liver exams. After a 3 x 24 DOF warping of the later examination to match the liver's pose in the earlier exam of the interval pair is performed, the lesion's volume change is estimated using the computed difference volume of the two data sets via a novel method that counts partial volume contributions and is insensitive to slight misregistration. A mathematically generated phantom is used to quantify accuracy in the presence of noise. We also quantify the accuracy of our CT liver registrations using microcoils implanted for chemotherapy. A probabilistic liver atlas is used to support automatic masking and liver-focused registration.  相似文献   
18.
The spectrum of CD30+ cutaneous lymphoproliferative disorders is characterized by the histology of a high-grade lymphoma but frequent clinical regression of skin lesions in lymphomatoid papulosis (LyP) and occasional regression in CD30+ large cell lymphomas (LCLs). A recent study shows that apoptosis may be a significant mechanism of regression of LyP (Arch Dermatol 133:828-833, 1997). Therefore, we studied expression of proteins that induce apoptosis, including CD27, CD40, CD95, and nerve growth factor receptor (NGF-R), as well as anti-apoptotic protein bcl-2 in skin lesions from 25 patients within the spectrum of CD30+ cutaneous lymphoma. Our results show consistent expression of CD95 (APO-1/Fas), but rare or absent expression of CD27, CD40, and NGF-R on tumor cells from both regressing LyP lesions and nonregressing CD30+ lymphomas. Bcl-2 was expressed at low levels in LyP and at high levels in pleomorphic CD30+ lymphomas. These results indicate that, in addition to CD30, CD95 expression is preferentially expressed at high levels in all cutaneous CD30+ lymphomas and suggest that CD95 may play a role in the regression of CD30+ skin lesions. Expression of bcl-2 appears to protect tumor cells from apoptosis in CD30+ lymphoproliferative disorders.  相似文献   
19.
The effects of age and gender on the single dose pharmacokinetics of avitriptan and its three metabolites were assessed in 15 young men, 15 young women, 15 elderly men and 15 elderly women. Avitriptan was administered as a 150-mg capsule after a 10-hour fast and serial plasma and urine samples were collected up to 36 hours after the dose. Plasma samples were analyzed for avitriptan and its metabolites, N-desmethyl avitriptan (ND048), O-desmethyl avitriptan (OD048), and methoxypyrimidinyl piperazine (MPP). Urine samples were analyzed for only avitriptan and MPP. Avitriptan was well tolerated in all four groups. The drug was rapidly absorbed with a median time to maximum plasma concentration (tmax) between 0.5 and 1.5 hours. No significant gender-related differences were found in the maximum plasma concentration (Cmax) and area under the concentration-time curve extrapolated to infinity (AUC0-infinity) of avitriptan. Renal clearance of avitriptan was significantly smaller in young women compared with young men, but this is clinically not relevant because only 2% to 3% of the total dose is excreted unchanged. Compared with the young volunteers, mean Cmax was approximately 50% higher in the elderly but there was no difference in the AUC0-infinity between the 2 age groups. Plasma concentrations of ND048, OD048, and MPP were each 50 to 100 fold lower than those of avitriptan. Hence some age- and gender-related differences found in the pharmacokinetics of avitriptan metabolites are probably not relevant in the assessment of overall safety and efficacy of avitriptan. Based on the pharmacokinetics and tolerability, no age or gender-related dose adjustment is necessary for avitriptan.  相似文献   
20.
M.E. Bland  C.A. Bailey  G. Davey 《低温学》1973,13(11):651-657
A study of bubble nucleation in liquid nitrogen and liquid hydrogen has been made in a 120 mm bubble chamber using a high speed cine camera.The initiation and growth of bubbles from artificially prepared cavities was studied. These cavities, produced in both copper and brass surfaces, had mouth radii ranging from 50 μm to 190 μm with depths varying from 110 μm to 500 μm. The liquids were superheated by either heating the surface containing the cavities or by reducing the pressure of the liquid, or by combining both of these methods.The heat fluxes required for initiation of boiling were greater than those required to sustain nucleation from a given site. The growth rate of the bubbles at constant liquid pressure was dependent on a number of factors. It changes as a bubble grew out of the thermal or superheated layer above the metal surface. After an initial period of more rapid growth the vapour volume increased linearly with time. The growth rate was dependent on the liquid used; being slower in liquid hydrogen than in liquid nitrogen. Formulae were obtained which predicted the observed variations in growth rate and departure volume.No nucleation was observed from the test surfaces for a pressure drop alone; the surfaces had to be heated before nucleation would occur. It is thought that this was due to the existence of a zero contact angle for cryogenic liquids on solid surfaces.  相似文献   
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