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111.
Forty-six medullary thyroid carcinomas (MTC) were subjected to a qualitative and quantitative characterization of native and sialic acid masked Lewisa (Lea) antigens. Immunohistochemical investigations included monoclonal antibodies (MABs) directed against alpha(2,3)-sialyl-Lea, i.e. CA19-9 (MAB 19-9), native Lea (MAB anti Lea) and alpha(2,3) sialyl type 1 structure, i.e. CA 50 (MAB C50). To detect sialic acid masked Lea reactivity, MAB anti-Lea was also applied to native and enzymatically desialylated tissue sections with and without masking of sialic acid residues by sialic acid and sequence specific lectins. Only 7 MTC (15%) displayed a weak expression of CA19-9, while 16 (33%) showed moderate positive staining for native Lea. Twenty-seven tumours exhibited a strong staining by the N'ase MAB anti Lea staining sequence. The latter could most effectively be inhibited by the simultaneous masking of alpha(2,3)-and alpha-(2,6)-linked sialic acid residues due to the comptetitive binding of sialic acid and sequence specific lectins: Maackia amurensis agglutinin (specific alpha(2,3)-linked sialic acid) and Sambucus nigra agglutinin (specific alpha(2,6)-linked sialic acid). Thus, in MTC the major portion of sialic acid masked Lea antigen reactivity is different from that detected by the MAB 19-9. The antigen reactivity is probably due to Lea structures containing both alpha(2,3) and alpha(2,6)-linked sialic acid residues. A highly significant correlation between the expression of CA50 and that detected by the N'ase MAB anti-Lea staining sequence indicates that the alpha(2,3)-sialyl type 1 chain represents a common intermediate structure within the pathway of the biosynthesis of sialylated Lea antigens, excluding the formation of CA19-9 via the formation of the disialyl type 1 structure. This is subsequently fucosylated to the corresponding sialic acid masked Lea. Preliminary clinicopathological studies indicate that the sialic acid masked Lea antigens detected by the N'ase MAB anti-Lea staining sequence are related to biologically aggressive MTC.  相似文献   
112.
Computed tomography (CT) has proven reliable in the early detection of acute haemorrhagic pancreatitis. In the present study the extrapancreatic changes at CT were studied in 60 patients with acute pancreatitis. The CT findings were correlated to the early "prognostic signs" by Ranson and the clinical course of the disease. All the patients with minor extrapancreatic changes recovered without complications. When moderate to severe extrapancreatic changes were seen the incidence of haemorrhagic pancreatitis and the risk of development of pseudocyst or abscess was high. In these patients a dynamic contrast enhanced CT should be done in order to select the patients with haemorrhagic pancreatitis.  相似文献   
113.
Journal of Immigrant and Minority Health - Up until recently incidences of tuberculosis (TB) had been declining for many years in Germany. The rise in TB cases coincided with a large increase in...  相似文献   
114.
PurposeThe purpose of this study was for an international panel of experts to establish consensus indications for distal rectus femoris surgery in children with cerebral palsy (CP) using a modified Delphi method.MethodsThe panel used a five-level Likert scale to record agreement or disagreement with 33 statements regarding distal rectus femoris surgery. The panel responded to statements regarding general characteristics, clinical indications, computerized gait data, intraoperative techniques and outcome measures. Consensus was defined as at least 80% of responses being in the highest or lowest two of the five Likert ratings, and general agreement as 60% to 79% falling into the highest or lowest two ratings. There was no agreement if neither threshold was reached.ResultsConsensus or general agreement was reached for 17 of 33 statements (52%). There was general consensus that distal rectus femoris surgery is better for stiff knee gait than is proximal rectus femoris release. There was no consensus about whether the results of distal rectus femoris release were comparable to those following distal rectus femoris transfer. Gross Motor Function Classification System (GMFCS) level was an important factor for the panel, with the best outcomes expected in children functioning at GMFCS levels I and II. The panel also reached consensus that they do distal rectus femoris surgery less frequently than earlier in their careers, in large part reflecting the narrowing of indications for this surgery over the last decade.ConclusionThis study can help paediatric orthopaedic surgeons optimize decision-making for, and outcomes of, distal rectus femoris surgery in children with CP.Level of evidenceV  相似文献   
115.
From 40 sets of five human gallstones obtained at cholecystectomy, four stones were subjected to either 125/250 (maximum generator output) or 250/500 (half maximum generator output) electromagnetic shock waves (treatments I/II and III/IV, respectively); the fifth stone was used for computed tomography (CT) and chemical analysis. Overall, 130 (81%) of 160 stones fragmented, including 72 (45%) adequately (fragments less than or equal to 5 mm). For the treatments I, II, III, and IV the overall fragmentation rates were 80%, 95%, 70%, and 80%, respectively. The corresponding percentages of adequate fragmentation ( less than or equal to 5 mm) were 38%, 70%, 30%, and 42%, respectively. The best results were thus obtained after application of 250 shock waves (maximum generator output; treatment II). Pure cholesterol stones (p less than 0.01), stones with a mean CT density less than or equal to 110 HU (p less than 0.001), and stones with a calcified rim (p < 0.05) fragmented significantly better, but adequate fragmentation ( less than or equal to 5 mm) was significantly determined by stone weight and diameter (p less than 0.001), bilirubin content (p less than 0.02), and calcium content (p less than 0.05). A weight greater than 500 mg and a diameter > 10 mm could be defined as stone characteristics with significant negative predictors of adequate fragmentation. However, because the experimental conditions in this in vitro study did not completely simulate clinical settings for various reasons, these observations must be interpreted accordingly.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
116.

Methods

After approval by the local Ethics Commitee and after informed consent had been given, 40 patients scheduled for elective maxillofacial surgery were included in this double-blind, randomized study. As a supplement to standardized general anaesthesia (isoflurane, N2O), the patients received either clonidine 5 μg/kg or placebo during the last hour of the operation. Blood pressure, heart rate, time of recovery, and sedation and pain scores were measured postoperatively. The occurrence of nausea, vomiting or shivering was noted, as were the requirements of piritramide for analgesia, which was administered on demand in titrating dosages, and of nifedipine for systolic blood pressure exceeding 180 mm Hg.

Results

The two groups were comparable regarding biometric parameters, ASA-classification and duration of anaesthesia. Clonidinetreated patients were later in opening their eyes (22.5±11.9 min vs 17.9±10.9; n.s.) and the ability to state their dates of birth returned later (32.2±11.6 min vs. 25.7±12.8;P<0.05). Pain was more frequent in the placebo group (P<0.05 after 30 min), and there-fore, these patients required much more piritramid (P<0.01). The sedation scores showed no significant differences. No vomiting occurred in the clonidine group, and shivering was less frequent (P<0.01). The placebo group received more nifedipine (P<0.05) because the rate-pressure product was higher (P<0.01).

Discussion

Opiates are frequently used as analgesics after maxillofacial surgery, even though their most common side effect—respiratory depression, nausea and vomiting—are particularly dangerous in these patients because of the obstruction of the upper respiratory tract. Self-titration of the opiate dosage on demand can decrease the incidence of serious side effects. Clonidine administered intraoperatively caused a profound reduction in analgesic requirements in this study. Additional opiate administration in the postoperative period was unnecessary in nearly all clonidine-treated patients. The attenuating effect on sympathoadrenergic reactions leads to lowering of the rate-pressure product and may be of advantage for patients suffering from arterial hypertension, angina pectoris or bronchial asthma. The slower emergence from anaesthesia following clonidine administration is probably caused by double-blind study properties preventing full consideration of the decreased isoflurane requirements after clonidine.  相似文献   
117.
In this paper I: (1) Describe something of the present situation in the United States and briefly contrast this with the state of affairs in other nations of the industrialised world. I emphasise health care but also allude to other social conditions: health care is merely one institution of a society and, just as do its other institutions, the system of health care reflects the basic world-view of that society. (2) Sketch the world-view and the philosophy which underwrites the use of a market system in distributing what are acknowledged to be critically important social goods like health care and higher education. I show that a well-functioning market can indeed be useful when it comes to distributing some, but not when distributing other goods. (3) Suggest that when competition and the market are used to regulate health care, technology—instead of being used to benefit patients—is apt to be used primarily to maximise individual profit: it becomes a weapon between what is often painted as warfare among health care providers and institutions. I argue that this state of affairs is based on an undue emphasis upon the demands of individual freedom to the detriment of the community. Finally (4) I suggest an alternative approach to balancing individual with communal interests, an approach which is neither based on a predominance of one with neglect of the other, nor on a dialectic balance between them, but rather upon an approach which sees both individual and communal interests as modifying forces in a complex homeostatic balance. Individual success, in any civilised sense of the term, is possible only in a viable and well-functioning community, and a well-functioning community is not possible without individual success: the two are inevitably interdependent and linked.  相似文献   
118.
119.
Differentiation of the non-dividing trypomastigote form of Trypanosoma cruzi, the causative agent of Chagas disease, to the dividing amastigote form normally occurs in cytoplasm of infected cells. Here we show that calyculin A. a potent inhibitor of protein phosphatases 1 and 2A, induces at pH 7.5 extracellular transformation of long slender trypomastigotes to round amastigote-like forms which acquire characteristic features observed after the normal differentiation process: repositioning and structural changes of the kinetoplast, release of surface neuraminidase, and expression of amastigote-specific epitopes. Calyculin A inhibits parasite phosphatases and changes in the phosphorylation of specific proteins occur during the transformation process. As an exposure of trypomastigotes to calyculin A concentrations as low as 1 nM and for only 1-2 h is sufficient to induce transformation, the inhibition of calyculin A-sensitive phosphatase(s) appears to play a major role in initiating the trypomastigote differentiation.  相似文献   
120.
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