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991.
992.
OBJECTIVE: To establish the pharmacodynamic and safety equivalence between 2 sustained-release forms of leuprorelin 11.25 mg and 3.75 mg, in the treatment of metastatic prostatic carcinoma. METHODS: 44 patients received subcutaneous injections of leuprorelin for 9 months (randomization: 2/l): either 11.25 mg every three months (n = 29) or 3.75 mg monthly (n = 15). Main criterion: centralized monthly assay of plasma testosterone (T). RESULTS: The equivalence of the 2 forms in terms of mean plasma testosterone was demonstrated (p = 0.002): 1 month: T = 0.19 +/- 0.03 ng/ml; 3 months: T = 0.27 +/- 0.04 ng/ml. Exploratory analysis did not reveal any significant difference between the groups for the number of patients castrated at each visit or for the number of patients with all T values < or = 0.5 ng/ml, or for clinical responses or safety. CONCLUSION: The 2 forms have a comparable efficacy and safety.  相似文献   
993.
OBJECTIVE: To review the morbidity and mortality among 68 premature infants treated with enterostomy for necrotizing enterocolitis. DESIGN: Data were collected retrospectively from hospital medical records to include the period between January 1, 1987, and September 30, 1997. SETTING: Tertiary care children's hospital. PATIENTS: A group of 68 infants aged 2 to 35 days (mean age, 12.5 days), weighing 1500 g or less, with necrotizing enterocolitis necessitating surgical enterostomy for treatment. INTERVENTIONS: Creation of any enterostomy during exploratory laparotomy for necrotizing enterocolitis and subsequent closure. MAIN OUTCOME MEASURES: Morbidity and mortality associated with infant enterostomy and its closure. RESULTS: Thirty-nine infants underwent ileostomy with mucous fistula, 16 underwent ileostomy with a Hartmann pouch, 7 had jejunostomy with mucous fistula, 2 had colostomy with mucous fistula, and 4 had colostomy with a Hartmann pouch. Eighteen (26%) of the 68 infants died in the postoperative period of sepsis (n = 10), continuing necrotizing enterocolitis (n = 5), or respiratory distress (n = 3). Of the remaining 50 infants, complications developed in 34 (68%). These complications included strictures requiring further resection at the time of enterostomy closure in 20 infants; stricture of the enterostomy requiring surgical revision in 6; incisional hernia in 3; parastomal hernia in 4; enterostomal prolapse or intussusception in 6 and 1, respectively; wound dehiscence in 4; wound infection in 8; small-bowel obstruction requiring laparotomy in 2; and anastomotic complications in 2. Only 16 enterostomies were closed uneventfully, with 3 of these infants subsequently dying of sudden infant death syndrome between 6 and 8 months after the operation. Of the surviving infants, 3 (6%) continue to require home hyperalimentation. CONCLUSIONS: Although enterostomy in infants with low birth weight with necrotizing enterocolitis may be lifesaving, it is also a major cause of morbidity. These data suggest the feasibility of a prospective study comparing resection and primary anastomosis with resection and enterostomy.  相似文献   
994.
Chromosomal homologies among the X chromosomes of species representative of eight bovid subfamilies and most of the recognized tribes were established using a combination of FISH and conventional G- and C-banding. Our analyses allowed for the delimitation of three X chromosome types represented, respectively, by cattle (Bovinae, tribe Bovini), the tragelaphines (Bovinae, tribe Tragelaphini), and a large assemblage comprising all the remaining subfamilies and their tribes (the Cephalophinae, Hippotraginae, Alcelaphinae, Antilopinae, Aepycerotinae, Peleinae, and Caprinae). The use of the bacterial artificial chromosome probe BAC 101 (which maps to Xp12 in cattle) and an Xp painting probe comprising sequences specific for the short arm of cattle Xp (Xp24-->p12) allowed us to orient this region, which has moved as a conserved euchromatic block during the evolution of the bovid X chromosome. We show that the differences between the three chromosomal types are attributable to a transposition, two inversions, and heterochromatic additions/deletions. A paucity of comparative mapping data precludes the assignment of the sequences contained in cattle Xp to either the presumed conserved (XCR) or the recently added (XAR) region of the eutherian X chromosome, and the reasons for the retention of these sequences as an evolutionarily conserved unit in the intrachromosomal restructuring of the bovid X across lineages remain enigmatic.  相似文献   
995.
OBJECTIVE: This study investigates whether factors that determine myocardial performance (preload, afterload, heart rate, and contractility) are altered after isolated unilateral pulmonary contusion. METHODS: Catheters were placed in the carotid arteries, left ventricles, and pulmonary arteries of anesthetized, ventilated (FiO2=0.5) pigs (31.2+/-0.6 kg; n=26). A unilateral, blunt injury to the right chest was delivered with a captive bolt gun (n=17) followed by tube thoracostomy. To control for anesthesia and instrumentation at FiO2 of 0.5, one group received tube thoracostomy only (sham injury; n=6). To control for effects of hypoxia without chest injury, an additional sham-injury group (n=3) was ventilated with FiO2 of 0.12. To generate cardiac function (i.e., Starling) curves, lactated Ringer's solution was administered in three bolus infusions at serial time points; the slope of stroke index versus ventricular filling pressure defines cardiac contractility. RESULTS: By 4 hours after pulmonary contusion, pulmonary vascular resistance, airway resistance, and dead space ventilation were increased, whereas PaO2 (72+/-6 mm Hg at FiO2=0.5) and dynamic compliance were decreased (all p < 0.05). Despite profound lung injury, arterial blood pressure, heart rate, cardiac filling pressures, and output remained within the normal range, which is inconsistent with direct myocardial contusion. The slope of pulmonary capillary wedge pressure versus left ventricular end-diastolic pressure (LVEDP) regression was reduced by more than 50% from baseline (p < 0.05), but there was no significant change in the slope of the central venous pressure versus LVEDP regression. By 4 hours after contusion, the slope of the stroke index versus LVEDP curve was reduced by more than 80% from baseline (p < 0.05). By the same time after sham injury with FiO2 of 0.12 (PaO2 < 50 mm Hg), the regression had decayed a similar amount, but there was no change in the slope after sham injury with FiO2 of 0.5 (PaO2 > 200 mm Hg). CONCLUSION: After right-side pulmonary contusion, the most often used estimate of cardiac preload (pulmonary capillary wedge pressure) does not accurately estimate LVEDP, probably because of changes in the pulmonary circulation or mechanics. Central venous pressure is a better estimate of filling pressure, at least in these conditions, probably because it is not directly influenced by the pulmonary dysfunction. Also, ventricular performance can be impaired by depressed myocardial contractility and increased right ventricular afterload even with normal left ventricular afterload and preload. It is thus conceivable that occult myocardial dysfunction after pulmonary contusion could have a role in the progression to cardiorespiratory failure even without direct cardiac contusion.  相似文献   
996.
AIM: To determine whether adult non-vegetarian Seventh-day Adventists differ in selected nutrition related health aspects from adult vegetarian Seventh-day Adventists. METHODS: One hundred and forty-one Seventh-day Adventist church members responded to a general health questionnaire. Forty-seven sex and age matched subjects (23 non-vegetarians and 24 vegetarians) were selected for further investigation. Blood lipids, serum vitamin B12, folate, haemoglobin and ferritin levels were measured along with stature, weight and blood pressure. A quantitative 7-day diet record was also completed. RESULTS: Body mass index was similar between the non-vegetarian and vegetarian groups but diastolic blood pressure was higher for non-vegetarian than vegetarian males. Even though the dietary vitamin B12 intake was significantly lower (p < 0.01) in the vegetarian group both vegetarians and non-vegetarians recorded similar serum vitamin B12 levels. The vegetarian and non-vegetarian groups had similar haemoglobin concentrations. While dietary iron intake was higher in the female vegetarian group, though predominantly in the non-haem form, the difference was not significant. Low serum ferritin levels were found in both female dietary groups even though the vegetarian group had a significantly (p < 0.05) higher vitamin C intake. Blood lipid levels were similar in the two diet groups even though the vegetarian group had a lower percentage energy contribution from total and saturated fat (p < 0.01) and consumed significantly less cholesterol. CONCLUSION: Both non-vegetarian and vegetarian Seventh-day Adventists appear likely to enjoy a lower risk of nutrition related chronic degenerative disease than the average New Zealander and have a satisfactory iron and vitamin B12 status.  相似文献   
997.
BACKGROUND: The purpose of this study was to determine the correlation between progression and regression of myointimal hyperplasia (MH) and cytokine production in experimental vein grafts. Although the autologous vein is the best suitable bypass conduit for reconstruction of peripheral arteries, at the end of the first year thrombosis in the coronary and lower extremity circulation ranges from 20% to 50%. Many of these failures are caused by MH. METHODS: In 76 inbred Lewis rats, a 1 cm long segment of inferior vena cava was inserted at the level of the abdominal aorta. The segments of inferior vena cava were obtained from syngeneic Lewis rats. In 56 animals the arterial vein graft was explanted 3 days (n = 10), 7 days (n = 10), 4 weeks (n = 26), and 12 weeks (n = 10) after operation. In 20 animals the vein graft was explanted 4 weeks after being in the arterial system and reimplanted as iliac venovenous bypass in syngeneic Lewis rats. These grafts were explanted 2 weeks (n = 10) and 8 weeks (n = 10) later. Grafts were analyzed by light and electron microscopy, morphometric study, and histochemical analysis and were put in an organ culture to assess cytokine production. RESULTS: We observed MH formation in arterial vein grafts and MH regression in reimplanted vein grafts (p < 0.001). MH formation was correlated with production of platelet-derived growth factor, basic fibroblast growth factor, interleukin-1, and tumor necrosis factor-alpha. MH regression was correlated with transforming growth factor-beta 1 production. CONCLUSIONS: On the basis of the results of our study, we conclude that MH formation in experimental vein grafts depends on production of platelet-derived growth factor, basic fibroblast growth factor, interleukin-1, and tumor necrosis factor-alpha, and MH regression depends on transforming growth factor-beta 1 production. Cytokine therapy may represent a valuable new treatment to prevent vein bypass failures caused by MH.  相似文献   
998.
The long-term complications of percutaneous dilatational tracheostomy   总被引:1,自引:0,他引:1  
  相似文献   
999.
1000.
The role of lysozyme in the immune immobilisation of Treponema pallidum is not yet fully understood. The T. pallidum immobilisation assay was used to demonstrate that the immobilisation and lysis of T. pallidum in vitro by antibodies (serum, IgG fraction or IgM fraction) and complement proceed in a lysozyme-independent mode. In the presence of lysozyme the rate of immobilisation increased. In contrast with its effect on Escherichia coli, the effect of lysozyme on T. pallidum was governed exclusively by its enzymic activity rather than by the cationic protein nature of the molecule. Lysozyme, released from stimulated phagocytes, induced formation of lysozyme antibodies in 59.6% of syphilis patients as determined by lysozyme antibody ELISA. The highest frequency was found in patients with untreated secondary syphilis, whereas untreated primary syphilis was only rarely accompanied by the presence of lysozyme antibodies. Cross-reactivities between lysozyme and treponemal antigens were excluded by immunoblotting. The autoantibodies did not influence the lysozyme activity. It was concluded that the formation of lysozyme antibodies is only an epiphenomenon in the host defence against treponemal infection.  相似文献   
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