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71.
The so-called hypertrophic column of Bertin is a normal variation and simply represents unresorbed polar parenchyma of one or both of the two subkidneys that fuse to form a normal kidney. It contains renal cortex, pyramids, and columns (septa) of Bertin. (Since all elements of the tissue are normal, that is, neither hypertrophic nor a displaced or embryonic rest, it is referred to as "junctional parenchyma.") When a masslike lesion is suspected at sonography or excretory urography, diagnosis of junctional parenchyma can be made with a high degree of certainty when sonography shows that the structure (a) is located between the overlapping portion of two renal sinus systems, (b) is bordered by a junctional parenchymal line and defect, (c) contains renal cortex, pyramids, and columns of Bertin, and (d) contains renal cortex that is continuous with the adjacent renal cortex of the same subkidney. 相似文献
72.
Hypotension is an uncommon complication of procedures involving extracorporeal circulation, including plasmapheresis. From November 1993 to March 1999, we treated 139 patients who underwent a total of 1,137 sessions of double filtration plasmapheresis (DFP). Hypotension was defined as a systolic blood pressure (BP) < 80 mm Hg or any decrease of systolic BP with systemic reactions. A total of 17 (1.5%) episodes of hypotension were documented in 15 patients during the study period. Hypotensive episodes occurred in 2.3% of patients with inflammatory neuropathy, 1.2% of patients with myasthenia gravis, and 1.2% of patients with all other medical diseases. Involvement of the autonomic nerve system (ANS) and a low baseline BP were associated with the occurrence of hypotension. Eight (47%) of 17 episodes were symptomatic and 2 were complicated with seizure. Patients with symptomatic hypotension had a higher level of systolic BP prior to DFP and a larger drop of systolic BP and pulse rate during hypotensive attacks compared to asymptomatic patients. Most hypotensive episodes were resolved briefly after intravenous infusion of saline within 30 min. Eight (47%) of the hypotensive episodes occurred during the first session of DFP treatment. Twelve (71%) of 17 episodes occurred during the last half period of treatment; 6 of them were noted during the terminating stage of DFP. In conclusion, in this series plasmapheresis-related hypotension occurred in 1.5% of DFP sessions and had a higher prevalence in patients with ANS instability and low BP. Extra caution in monitoring BP during DFP therapy is warranted in these vulnerable patients, especially during the termination phase of the first DFP session. 相似文献
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74.
Jun-Jun Yeh Wu-Huei Hsu We-Tao Huang Jhi-Joung Wang Shung-Tai Ho Albert Kao 《Tumour biology》2003,24(3):151-155
The multidrug resistance gene 1 encoding human P-glycoprotein (Pgp) is thought to play an important role in the multidrug resistance of lung cancer. The purpose of this study was to predict chemotherapy response by technetium-99m tetrofosmin (Tc-99m TF) lung single photon emission computed tomography (SPECT) and compare Pgp expression in patients with untreated small cell lung cancer (SCLC). Forty patients with untreated SCLC received Tc-99m TF lung SPECT prior to chemotherapy. The chemotherapy response was evaluated in the 3rd month after completion of treatment. Immunohistochemical staining of Pgp expression was performed on multiple nonconsecutive sections of biopsy specimens. By quantitative analyses, tumor to background ratios were 1.86 +/- 0.27 and 1.17 +/- 0.26 for patients with a good and poor response, respectively (p < 0.05). All of the 20 patients with a good chemotherapy response also had a positive Tc-99m TF lung SPECT and negative Pgp expression. In contrast, only 4 of the 20 patients with a poor chemotherapy response had a positive Tc-99m TF lung SPECT. Moreover, 10 of the 20 patients with a poor chemotherapy response also had negative Pgp expression (p < 0.05). Therefore, we concluded that Tc-99m TF lung SPECT can accurately predict the chemotherapy response, and Tc-99m TF lung SPECT findings can be partially compatible with Pgp expression in patients with untreated SCLC. 相似文献
75.
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77.
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
78.
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
79.
The impact of external feedback on computer-assisted learning for surgical technical skill training 总被引:4,自引:0,他引:4
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
80.
Comparison between double-filtration plasmapheresis and immunoadsorption plasmapheresis in the treatment of patients with myasthenia gravis 总被引:1,自引:0,他引:1
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