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91.
Objective: To evaluate the incidence and severity of apnoea and bradycardia in hospitalized preterm infants following immunization at 2 months of age, and identify risk factors.
Methodology: A prospective study of 98 preterm infants, of gestational age 24–31 weeks, immunized at approximately 2 months post natal age with diphtheria-tetanus-whole cell pertussis vaccine (DTPw) in the neonatal intensive care unit (NICU) at King George V Hospital Sydney. Half the infants also received Haemophilus influenzae type b conjugate vaccine (Hib) simultaneously. All infants were monitored for apnoea and bradycardia in the 24 h periods pre- and post immunization.
Results: Only one infant had apnoea and/or bradycardia pre-immunization compared with 17 post immunization. For 12 infants these events were brief, self-limiting and not associated with desaturations (oxygen saturation <90%). However, for five infants (30%) these events were associated with oxygen desaturation and two of these infants required supplemental oxygen. The group that had apnoea and/or bradycardia and the group that did not were not significantly different in terms of gestational age, birth weight and other variables. Infants who received Hib together with DTPw were less likely to have apnoea and/or bradycardia than those given DTPw alone.
Conclusion: When considering immunization for preterm infants, the benefits of early immunization must be balanced against the risk of apnoea and bradycardia. We recommend that the cardio-respiratory function of hospitalized infants born at less than 31 weeks gestation be monitored for 48 h post immunization.  相似文献   
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Yeh KA  Jillella AP  Wei JP 《The American surgeon》2000,66(3):250-4; discussion 255
Despite increasing public awareness and widespread availability of mammography, many patients will present with locally advanced breast cancers. The role of surgery remains controversial. Between 1993 and 1998, 47 of 393 (11.9%) breast cancer patients presented with T4 (inflammatory or locally advanced) carcinoma. We reviewed multimodality management, clinical response to neoadjuvant therapy, perioperative course and complications, and local control. Forty-six women and one man were diagnosed with clinical T4 breast cancer. There were 24 white and 23 African-American patients. Mean age at presentation was 54.5 (range, 31-88) years. Twenty-three patients had clinical metastases to axillary nodes, and five had distant metastases at the time of diagnosis. For these women, intent was for personal hygiene and control of pain. Neoadjuvant chemotherapy was given for 34 of 47 (72%) with 25 of 34 (73.5%) having partial or complete clinical response. There was no response or progression of disease in 9 of 34(26.5%). Forty-six patients underwent radical or modified radical mastectomy, whereas a single patient underwent breast conservation treatment. Twelve required tissue transfer for wound coverage. Although eight developed minor wound complications (cellulitis/flap separation), there were no major wound complications. Pathologically negative margins were achieved in all but one patient. To date, five women have developed local recurrence in either the chest wall (three) or axilla (two). Average time to local recurrence was 7.8 months. There is no evidence of local failure in the remaining 87 per cent. Locally advanced breast cancer is a common occurrence in certain populations. Multimodality management remains the standard of care. Surgical resection may allow for successful local control and, in certain situations, long-term cure.  相似文献   
95.
Video-assisted endoscopic thyroidectomy   总被引:55,自引:0,他引:55  
BACKGROUND: Several experimental and clinical reports concerning endoscopic parathyroid surgery have appeared. However, reports concerning minimally invasive surgery for thyroid remains rare. Herein we present a new method, called video-assisted endoscopic thyroidectomy (VAET), for the management of various benign thyroid diseases. METHODS: In all, 16 consecutive patients who underwent VAET for benign thyroid diseases were retrospectively studied. The study group included nodular hyperplasia in 8 patients, follicular adenoma in 6, and Hurthle's tumor and simple cyst in 1 each. A 2 to 3 cm transverse incision was made on the suprasternal notch. The wound was deepened to expose the underlying trachea from which the plane of the thyroid fascia was accessed directly, and the working space was established with lifting method using conventional instrument. All surgical procedures could be manipulated and monitored under laparoscopy without gas insufflation. The ultrasonically activated scalpel was the principal instrument used for VAET. RESULTS: All 16 patients underwent VAET successfully without conversion to open thyroidectomy. The surgical procedures included lobectomy in 13 and extirpation in 3. The operation time ranged from 28 minutes to 5 hours (mean 1 hour, 42 minutes). For the 5 most recent cases, lobectomy took an average of 2 hours, whereas extirpation less than 40 minutes. The tumor size ranged from 3.5 cm to 8.0 cm (mean 5.8 cm). There were no surgical complications. All patients but 1 were discharged on postoperative day 2. During follow-up, all patients demonstrated euthyroid function and satisfactory cosmetic results. CONCLUSIONS: VAET emerges as a promising minimally invasive surgical technique replacing conventional thyroidectomy for benign thyroid diseases in selected cases, with the advantage of satisfactory cosmetic results.  相似文献   
96.
BACKGROUND: Computer-assisted learning (CAL) offers a number of potential advantages for surgical technical skills teaching. The purpose of this study was to evaluate the impact of individualized external feedback on surgical skill acquisition when a CAL package is used for instruction. METHODS: Freshman and sophomore students participated in a 1-hour CAL session designed to teach them how to tie a two-handed square knot. One group received individualized external feedback during the session and the other group did not. Subjects were videotaped performing the skill before and after the session. The tapes were independently analyzed, in blinded fashion, by three surgeons. Three measures were obtained: the total time for the task, whether or not the knot was square, and the general quality of the performance using a rating scale. RESULTS: Data from 105 subjects were available for final analysis. For both groups there were significant increases in the proportion of knots that were square when the posttest performance was compared with the pretest performance but there was no difference between groups on this measure. Comparison of the performance scores demonstrated that both groups had a significant improvement after the session but the performance scores were significantly better in the group that had received feedback. CONCLUSIONS: Novices in both groups using CAL showed improvement in two of the outcomes measured, suggesting that subjects in both groups attained some degree of competence with this skill. The higher posttest performance score for the group receiving feedback demonstrates that external feedback results in a higher level of mastery when CAL is used to teach surgical technical skills.  相似文献   
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Yeh JH  Chiu HC 《Journal of neurology》2000,247(7):510-513
Two techniques for plasmapheresis are used in the treatment of myasthenia gravis (MG): immunoadsorption (IA) and double filtration (DR). This controlled study evaluated the differences between these techniques in clinical effects and serological changes. Five patients with generalized MG (clinical states IIb and III) were enrolled; each patient received IA and DF plasmapheresis on separate occasions. Immunosorba TR-350 with an affinity to acetylcholine receptor antibodies (AchRAb) was used for IA, while Evaflux 4A was used as the plasma fractionator for DF. Each course of treatment consisted of five sessions of apheresis. MG score, titers of AchRAb, immunoglobulins (IG), and plasma biochemistry were assessed by blinded examiners before and immediately after the entire course of treatment. Both treatments effectively ameliorated symptoms of MG. There were no significant changes in MG score between the two groups (IA vs. DF: 2.2 vs. 2.6, P>0.5). IA had a higher clearance rate of AchRAb than DF (66 % vs. 54 %, P<0.05), while DF removed more IgA (72 % vs. 21 %, P< 0.05) and IgM (89 % vs. 57 %, P<0.01) than did IA. Although IA removed AchRAb more effectively than DF, the clinical effects between these two treatments were similar. The titers of AchRAb cannot reflect the clinical severity. Some circulating factors other than AchRAb may contribute to the pathogenesis of MG. Received: 10 September 1999, Received in revised form: 7 February 2000, Accepted: 24 February 2000  相似文献   
99.
Keratoconjunctivitis sicca (KCS) is a common complication of graft-versus-host disease (GVHD), and may lead to corneal epithelial defect and melting. In contrast, recurrent corneal calcareous degeneration and perforation is rare. A 46-year-old woman developed chronic GVHD after bone marrow transplantation for aplastic anemia. Severe KCS with corneal melting and calcium deposits were noted in the left eye. Penetrating keratoplasty was performed because of corneal perforation, but poor re-epithelialization and calcium deposition recurred. Lamellar keratectomy and amniotic membrane transplantation (AMT) were performed, but acute calcareous degeneration developed with subsequent recurrence of corneal perforation. After regraft, AMT and tarsorrhaphy, the corneal graft remained clear for 3 months. However, breakdown of the corneal epithelium occurred 3 weeks after spontaneous separation of tarsorrhaphy. Six months later, corneal perforation recurred again along with exacerbation of GVHD. Regraft was performed, but the patient refused tarsorrhaphy and AMT. Poor re-epithelialization persisted after regraft. Corneal melting with impending corneal perforation ensued. Further corneal surgery was refused and the patient chose to undergo evisceration. This case demonstrates that the ocular complications of GVHD may be severe enough to lead to corneal perforation and calcareous degeneration that is recalcitrant to medical and surgical treatment.  相似文献   
100.
Osteosarcoma is a very malignant bone tumor which has a high metastatic potential and usually lead to poor prognosis. The adhesion of tumor cells to the endothelium or extracellular matrix (ECM) is an essential step in the metastatic cascade. We investigated the effect of thrombin on the adhesion activity of the osteosarcoma cell line, ROS 17/2.8. Incubation with the low concentrations of thrombin (0.01-5 U/ml, 5 min to 24 h) elevated the adhesion activity of ROS 17/2.8 to both human umbilical vein endothelial cells (HUVEC) and extracellular matrix, with the peak effect at the concentration of 0.5 U/ml for 30 min at 37 degrees C. The ROS 17/2.8 cells responded to thrombin by a peak effect of increased adhesion to HUVEC (5.5 folds vs. control) and fibronectin (4.8 folds) after thrombin pretreatment (0.5 U/ml, 30 min, 37 degrees C). Pretreatment with monoclonal antibodies against beta3 integrins, including anti-alphavbeta3, 10E5 and 7E3, effectively antagonized the thrombin-enhanced cell adhesion activity, whereas anti-alpha3beta1 and anti-alpha5beta1 did not antagonize the enhanced cell adhesion. Rhodostomin, an Arg-Gly-Asp (RGD)-containing snake venom peptide, and synthetic peptide RGDS also blocked the thrombin-enhanced ROS 17/2.8 cell adhesion. This study demonstrated that thrombin enhanced the cell adhesion of ROS 17/2.8 cells to HUVEC or ECM through an upregulation of beta3 integrins, and rhodostomin was a strong inhibitor on thrombin-enhanced cell adhesion, either to HUVEC or fibronectin substratum.  相似文献   
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