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91.
The earliest ascertainable clues and symptoms of carcinoma of the colon and rectum have been considered, and factors aiding in an early and positive diagnosis have been reiterated.The most common initial symptoms of malignant growths of the right side of the colon are pain, palpable tumor and indefinite dyspepsia. Lesions in the transverse colon manifest themselves first by pain, obstructive attacks and developing or increasing constipation. Carcinoma of the descending colon and sigmoid is manifested first by increasing constipation or obstruction, pain, rectal bleeding and diarrhea. Carcinoma of the rectosigmoid and rectum is suggested by a change in bowel habit, either constipation or diarrhea, and rectal bleeding. The diagnosis of malignant lesions of the colon is rendered certain by roentgenographic examination. The presence of lesions in the sigmoid or below it may be proved by proctoscopic and digital examination of the rectum. 相似文献
92.
JV Aranda A Varvarigou K Beharry R Bansal C Bardin H Modanlou A Papageorgiou S Chemtob 《Acta paediatrica (Oslo, Norway : 1992)》1997,86(3):289-293
The elimination, disposition and protein binding of ibuprofen (IBU) in premature infants were studied for use in the prevention of intraventricular hemorrhage and closure of patent ductus arteriosus. The kinetic profile of i.v. IBU lysine (10 mg/kg bolus) given within the first 3 h after birth was studied in 21 premature neonates (mean birthweight = 944.7 g, range: 575–1450 g; gestational age: 26.8 weeks, range: 22–31 weeks). Blood samples (0.3 ml/sample) were obtained at time 0 and at 1, 3, 6, 12, 24, 48, and 72 h post-dose for IBU by high-performance liquid chromatography (HPLC). Kinetic analyses assumed applicability of one open-compartment model and calculations from the model-independent areas under the time concentration curve (AUC). Data (mean ± SEM) show that apparent volume of distribution (AVd) was 62.1 ± 3.9 ml/kg, plasma t 1/2 beta was 30.5 ± 4.2 h, elimination rate constant (kel ) was 0.032 ± 0.004 h-1 plasma clearance was 2.06 ± 0.33 ml/kg/h and plasma concentration (Cp) at 1 h was 180.6 ±11.1 mg/1. Gestational age and birthweight were not related to drug elimination. In 10 neonates, IBU maintenance dose of 5 mg/kg once daily on days 2 and 3 generated mean Cp of 116.6 ± 54.5 mg/1 and 113.6 ± 58.2mg/1, respectively. Protein binding by ultrafiltration and capillary electrophoresis showed that the percentage bound IBU was significantly lower in full term cord plasma (94.98 ± 0.39%, n = 26) compared to adult plasma protein (mean ± SE = 98.73 ± 0.31%, n = 8, p < 0.0001). Compared to data from adults and older children, IBU elimination is markedly prolonged in neonates and protein binding is slightly lower. Thus, investigational and clinical therapeutic regimens should be adjusted to account for decreased drug disposition to ensure safe and effective therapy. 相似文献
93.
Meniscal tears of the knee: accuracy of MR imaging 总被引:39,自引:0,他引:39
Before surgery, 277 menisci in 144 knees were examined with magnetic resonance (MR) imaging. They were then examined directly with arthroscopy or arthrotomy. Menisci were graded on a scale of 1-3 according to the character of the intrameniscal MR imaging signal. At surgery, 137 of 154 (89%) menisci exhibiting only grade 1 or grade 2 signal were found to be normal. One hundred sixteen of 123 (94%) menisci exhibiting intrameniscal signal communicating with a meniscal articular surface (grade 3 signal) had tears. If only a grade 3 signal is considered consistent with meniscal tears, then MR findings and surgical findings agreed in 91.3% of menisci. MR imaging can separate surgically significant from nonsignificant meniscal lesions and is useful in the noninvasive preoperative screening of suspected meniscal tears. 相似文献
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Approximately 2154 regional blood centers and hospital-based blood banks and transfusion services responded to the 1991 American Association of Blood Banks Institutional Membership Questionnaire that elicited data from 1990. Information from 2144 institutions was considered valid. Questionnaire topics were donor blood collections, hemapheresis, perioperative cell salvage, component usage, and transfusion-associated diseases. Institutional members reported collecting 9.3 million units, of which 90.9 percent were for allogeneic use in the community, 6.0 percent were for autologous use, and 3.1 percent were directed donations. The percentage of directed-donor units that were crossed over for allogeneic use (51%) was greater than the percentage of units transfused to the designated patient (49%). Only 12.5 percent of institutions reported obtaining specific consent for transfusion. Of the 15.4 million transfused blood components, 8.5 million were red cells, 4.1 million were platelets, 1.8 million were fresh-frozen plasma, and 0.9 million were cryoprecipitate. There were 1263 reported cases of transfusion-associated hepatitis. Approximately 44 percent of the patients who were tested proved positive for hepatitis B surface antigen, and 80 percent of the patients who were tested proved positive for antibody to hepatitis C. The questionnaire's aggregate results can be used to assess current patterns of blood donation and transfusion activities. 相似文献
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David L. H. Bennett Martin Koltzenburg John V. Priestley David L. Shelton Stephen B. McMahon 《The European journal of neuroscience》1998,10(4):1282-1291
Nerve growth factor (NGF) has a well characterized role in the development of the nervous system and there is evidence that it interacts with nociceptive primary afferent fibres. Here we applied a synthetic tyrosine kinase A IgG (trkA-IgG) fusion molecule for 10–12 days to the innervation territory of the purely cutaneous saphenous nerve in order to bind, and thereby neutralize endogenous NGF in adult rats. Using neurophysiological analysis of 152 nociceptors we now show that sequestration of NGF results in specific changes of their receptive field properties. The percentage of nociceptors responding to heat dropped significantly from a normal 57% to 32%. This was accompanied by a rightward shift and a reduced slope of the stimulus response function relating the intracutaneous temperature to the neural response. The number of nociceptors responding to application of bradykinin was also significantly reduced from a normal of 28% to 8%. In contrast, the threshold for mechanical stimuli and the response to suprathreshold stimuli remained unaltered, as did the percentage of nociceptors responding to noxious cold. The reduced sensitivity of primary afferent nociceptors was accompanied by a reduction in the innervation density of the epidermis by 44% as assessed with quantitative immunocytochemical analysis of the panaxonal marker PGP 9.5. This demonstrates that endogenous NGF in the adult specifically modulates the terminal arborization of unmyelinated fibres and the sensitivity of primary afferent nociceptors to thermal and chemical stimuli in vivo. 相似文献