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81.
The pathophysiology of spondylotic cervical myeolopathy is still a matter of discussion. This paper presents a series of 126 patients operated on using a ventral approach. In 47% of the patients only a spondylotic narrowing of the spinal canal was present and in 35% an additional disc herniation was found. In 13% of the cases however a soft disc without spondylotic spures was found and in 5% a dislocation of vertebral bodies. We found a marked male preponderance of 77%, mean age was 51.6 years, ranging from 25–50 years. Most patients were operated on at the levels of C4/5 and C5/6. Observation time covered a period of 3–10 years. The outcome was rated relatively to the preoperative degree of disablement using a questionnaire for the patients and their family doctors. We found a marked difference in the answers, especially in rating deterioration, which was stated by patients in 34%, by physicians only in 12%. Another finding was the time-related out-come. We found best results with 75% improvement and 5% deterioration between 3–6 months postoperatively, with increasing time the results decreased to 33% improvement, 33% identical statys and in 33% a deterioration related to the preoperative status must be noted.  相似文献   
82.
83.
Pharmacokinetics and bioavailability of benperidol were determined in 13 schizophrenic patients after acute administration of 6 mg benperidol as an intravenous (i.v.) bolus injection, orally as liquid, and orally as tablets using a partially randomized cross-over design. Drug plasma levels were determined by high performance liquid chromatography with electrochemical detection and subjected to model independent pharmacokinetic analyses. After i.v. dosing the geometric means (mean-g) were 3.2 min for the distribution half-life, 5.80 h for the elimination half-life (t 1/2), 4.21 l/kg for the distribution volume, 7.50 h for the mean residence time (MRT), and 0.50 l/(h*kg) for the clearance. After oral administration as liquid and as tablet mean-g data for the time lag until the first appearance of measurable plasma concentrations were 0.33 and 1.1 h, mean-g t 1/2 values were 5.5 and 4.7 h, respectively, mean-g t max data were 1.0 h and 2.7 h, mean-g MRT values were 8.44 and 8.84 h, and mean-g C max maxvalues were 10.2 and 7.3 ng/ml. Differences between liquid and tablet administration were statistically significant for time lag,t max, andC max. Mean-g absolute bioavailabilities were computed as 48.6% after liquid and 40.2% after tablet administration respectively. All parameters studied exhibited large intersubject variation. The plasma concentrations of the presumed metabolite reduced benperidol were found to be very low.  相似文献   
84.
An early common element during anterior-posterior axis formation amongst amniotes is the primitive streak, running longitudinally in the two-layered embryonic disc. In mammals the primordium of this transient structure is the first definite morphological sign of the anterior-posterior axis, while in avian embryos the axis is visible and apparently defined earlier. Here we scrutinize suggestions that in mammals also there are earlier signs of axis formation by using correlative low and high-resolution light microscopy on tissues from rabbit embryos at 6.3 and 6.5 days post-conception, i.e. immediately before and after primitive streak formation. A series of semithin sections were cut from resin-embedded embryonic discs that had been photographed previously at low power. In embryos at 6.5-days post-conception the primitive streak is as long as up to half the diameter of the embryonic disc, extending anteriorly from a thickening, here called the posterior node, at the posterior margin, which contains the first mesoderm cells ingressing from the epiblast. On both sides of the primitive streak there is a triangular area that appears light in surface views of fixed embryos and correlates with stretches of low-columnar simple epithelium in an otherwise high-columnar pseudostratified epiblast. Within the anterior margin, which has a sharper contour than the rest of the circumference of the embryonic disc, there is a narrow, crescent-shaped dark zone caused by increased cellular height and number in both epiblast and hypoblast. These characteristics of the anterior margin are also found at 6.3 days post-conception, at which stage there is no sign of a primitive streak or a posterior node. The posterior margin, in contrast, is ill-defined in these earlier embryos, or there is a light crescent within the posterior margin, which has the same histological characteristics as the bilateral posterior triangular areas of primitive streak stages. Because the anterior differentiation occurs prior to primitive streak formation and is a sign of both the anterior-posterior and the transverse axes of the embryonic disc, and because some of its histological characteristics are found in primate and human embryos, we propose to name this structure the anterior marginal crescent and to add it to the list of transient structures that gradually establish the principal body axes in mammals. The anterior manifestation of body axes in mammals is thus essentially different from axis development in the avian embryo, where differentiation of these axes is first manifest at the posterior margin.Supported by the Deutsche Forschungsgemeinschaft (Vi 151/1-1); part of the results were presented at the First Joint Meeting of the Anatomical Society of Great Britain and Ireland and of the Anatomische Gesellschaft, Southampton, December 1994, and will be published in abstract form (J Anat, in press)  相似文献   
85.
Priming of CBA/J mice with different doses of antigen has aprofound effect on the ratio of IgE versus IgG antibodies appearingupon Immunization. Repeated injections of minute doses induceIgG and high titers of IgE antibodies. Large doses elicit ahigh IgG but a very low IgE antibody titer. In order to studythe modalities for activation and inactivation of IgE-producingB cells, an in vitro culture system was established in whichspleen cells from animals primed with keyhole limpet hemocyaninwere re-stliulated with antigen. In contrast to the expectationfrom the in vivo situation, spleen cells from animals Immunizedwith large doses of antigen and virtually lacking IgE antibodiesproduce high amounts of IgE antibodies upon re-stimulation invitro. The titers in spleen cell cultures from mice primed withminute doses remain proportional to the response measured asserum antibodies. In accordance with the induction of high amountsof IgE antibodies in spleen cell cultures from mice primed withlarge doses, the frequency of IgE antibody-secreting cells wasraised drastically, 1000-fold. The in vitro response is a trueanamnestic response. The sudden appearance in high frequencyof IgE antibody-forming cells among spleen cells isolated fromprimed mice which have high IgG but virtually no IgE antibodytiters is as yet unexplained and the origin of the B memorycells has not yet been traced. The answer might be crucial forour understanding of the down-regulation of the IgE Immune responses.  相似文献   
86.
Background: Opioids can produce peripheral analgesic effects by activation of opioid receptors on sensory nerves. This study was designed (1) to examine a novel route of opioid administration, the intraperitoneal injection; (2) to compare this to interpleural application, and (3) to compare opioid with local anesthetic effects under both conditions.

Methods: At the end of laparoscopic cholecystectomy, 110 patients received the following injections in a double-blind, randomized manner: Group 1 (n = 18) was given intraperitoneal morphine (1 mg in 20 ml saline) and 20 ml intravenous saline. Group 2 (n = 17) received intraperitoneal saline and 1 mg intravenous morphine. Group 3 (n = 15) received 20 ml 0.25% intraperitoneal bupivacaine and intravenous saline. Group 4 (n = 20) received interpleural morphine (1.5 mg in 30 ml saline) and 30 ml intravenous saline. Group 5 (n = 20) received interpleural saline and 1.5 mg intravenous morphine. Group 6 (n = 20) received 30 ml 0.25% interpleural bupivacaine and intravenous saline. Postoperative pain was assessed using a visual analog scale, a numeric rating scale, and the McGill pain questionnaire. Pain localization, supplemental analgesic consumption, vital signs, and side effects were recorded for 24 h.

Results: Neither intraperitoneal nor interpleural morphine produced significant analgesia after laparoscopic cholecystectomy (P > 0.05, Kruskal-Wallis test), whereas interpleural bupivacaine was effective (P < 0.05, Kruskal-Wallis test, up to 6 h postoperatively) but not intraperitoneal bupivacaine (P > 0.05, Kruskal-Wallis test). Shoulder pain was not prevalent in the majority of patients during the first 6 h. By 24 h, about half of the patients complained of shoulder pain, which was rated "low" by about one-third of all patients. No significant side effects occurred.  相似文献   

87.
Hirayama’s disease is a benign juvenile form of focal amyotrophy affecting the upper limbs. Previous studies have suggested that the disorder is a neck flexion induced cervical myelopathy. We report clinical and magnetic resonance imaging findings in nine patients with Hirayama’s disease. Cervical imaging of seven patients revealed spinal cord changes consisting of focal atrophy and foci of signal alterations. On neck flexion a forward movement and mild reduction in the anteroposterior diameter of the lower cervical cord against the vertebral bodies was noted in affected individuals as well as in five normal controls. In contrast to earlier reports, none of our patients showed complete obliteration of the posterior subarachnoid space. Measurement of the anteroposterior spinal cord diameter in each vertebral segment (C4–C7) revealed no significant differences in the degree of spinal cord flattening between the two groups. Furthermore, two of our patients had significant degenerative changes in the cervical spine (disc herniation, retrospondylosis) contralateral to the clinically affected side. These degenerative changes resulted in a marked cord compression on neck flexion but were not associated with ipsilateral clinical abnormalities or spinal cord alterations. Our results argue against a flexion-induced cervical myelopathy and support the view that Hirayama’s disease is an intrinsic motor neuron disease. Received: 15 March 1999 Received in revised form: 25 May 1999 Accepted: 1 June 1999  相似文献   
88.
Background: Most germs causing postoperative endophthalmitis derive from the conjunctival bacterial normal flora. Postoperative endophthalmitis is often induced by staphylococcal germs. The application of polyvidone-iodine solution to the conjunctiva is one possibility to reduce potential endophthalmitis-causing bacteria. The aim of this study was to evaluate the effectiveness of 1 % polyvidone-iodine solution concerning the reduction of colonization with staphylococci in the course of intraocular surgery. This is to evaluate the effectiveness of 1 % polyvidone-iodine solution concerning coagulase-negative and positive staphylococci.  相似文献   
89.

Purpose

We present a time and labor saving embedding technique for a full-thickness bowel flap tube used as a continent outlet.

Materials and Methods

In 17 patients the bowel flap tube was extramurally embedded instead of being submucosally tunneled. The reservoir was attached to the abdominal wall to reinforce the continence mechanism and prevent the tunnel from opening.

Results

All 17 patients are completely continent and 14 of 16 evacuate urine easily with a 14F catheter. Due to recurrent stomal stenosis 1 patient with severe diabetes has undergone incontinent diversion.

Conclusions

Our described tunneling procedure for the full-thickness bowel flap tube is easy to perform and provides excellent continence.  相似文献   
90.

Objectives

To analyze the effectiveness of adjuvant polychemotherapy after radical cystectomy for nonorgan-confined transitional cell bladder cancer (Stages pT3b, pT4a, and/or pN1 or pN2).

Methods

Of 166 consecutive patients undergoing cystectomy at two institutions from 1987 to 1993, 80 received adjuvant polychemotherapy with methotrexate, vinblastine, and cisplatin plus doxorubicin (MVAC) or epirubicin (MVEC), whereas 86 had cystectomy only. The patients were evaluated for relapse-free survival and length of progression-free interval on the basis of follow-up data obtained in 1995 and 1996.

Results

Kaplan-Meier analysis revealed a significantly higher progression-free rate for patients after adjuvant chemotherapy (P=0.0002, log-rank test). With and without adjuvant chemotherapy, prognosis declined in a stepwise manner, depending on the extent of lymph node involvement. Nevertheless, the superior prognosis of the chemotherapy group could be demonstrated at each lymph node stage. Of the 166 patients, 49 had initially entered a prospective trial comparing adjuvant with no adjuvant treatment. That study was discontinued in December 1990 after an interim analysis revealed a significant prognostic advantage in favor of the 26 patients randomized to receive chemotherapy compared with the 23 control patients. Current follow-up data continue to demonstrate a significant improvement in progression-free survival in favor of patients randomized to receive adjuvant chemotherapy (P=0.0040). The follow-up period of patients living free of disease ranges from 58 to 96 months.

Conclusions

Adjuvant chemotherapy with MVAC/MVEC leads to significant prolongation of relapse-free survival and improvement of the definitive cure rate after radical cystectomy for locally advanced transitional cell carcinoma of the urinary bladder.  相似文献   
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