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81.
Cervical root stimulation (CRS) was compared with conventional EMG, nerve conduction, and late response studies in 34 patients with possible cervical radiculopathy. Cervical roots were stimulated by monopolar needles inserted into paraspinal muscles, recording compound muscle action potentials in biceps, triceps, and abductor digiti minimi muscles. In 18 patients with clinical evidence of radiculopathy, EMG was abnormal in 11 (61%), but CRS was abnormal in all 18. Of 16 patients with symptoms but no signs of radiculopathy, EMG was abnormal in 5 (31%) and CRS was abnormal in 9 (56%). 相似文献
82.
In spite of extensive investigations of the rat's meso-cortico-limbic system, the dopaminergic (DA) innervation of the hippocampal formation (HF) has not heretofore been visualized by histochemical techniques. However pharmacological and biochemical studies strongly suggested its existence. We used tyrosine-hydroxylase (TH) as an immunocytochemical marker of DA neurons in rats in which the noradrenaline cortical innervation was previously destroyed by neurotoxins. The absence of noradrenergic axons was routinely controlled with dopamine-beta-hydroxylase immunocytochemistry. TH-positive axons, thus DA axons, reach the HF primarily through the fimbria in which they occupy a specific lateral sector. They innervate the ventral and caudal parts of the HF, the subiculum and the adjacent CA1 hippocampal field being the main targets. This DA terminal field in the HF, matches with the area projecting toward the nucleus accumbens. Thus the hippocampo-striatal projections which represent a link of functional importance between the limbic and central motor systems might be modulated by the dopaminergic meso-cortico-limbic pathway. The present immunocytochemical study confirms the very dense innervation of the entorhinal cortex (EC): DA axons are organized in dense fiber islands and occupy primarily the superficial layers (I-II-III). Da innervation predominates in the lateral part of EC, which is the site of multimodal cortical afferences and therefore relays information between the whole neocortex and the hippocampus. Thus the DA system could play an important role of modulation on hippocampal and parahippocampal functions. 相似文献
83.
Management of abdominal sepsis 总被引:2,自引:0,他引:2
D. Berger K. Buttenschoen 《Langenbeck's archives of surgery / Deutsche Gesellschaft fur Chirurgie》1998,383(1):35-43
Introduction: Today the management of the different forms of peritonitis is generally standardised. The classification of primary and secondary
peritonitis is well accepted. From a pathophysiological point of view, postoperative and post-traumatic peritonitis should
be considered as independent entities. The bacteriological isolates from the inflamed peritoneal cavity do not correlate with
the clinical course, and the occurrence of enterococci and bacteroides may be slightly related to ongoing infectious complications.
Classification: Valuable scoring systems mainly rely on systemic signs of the septic disease and seem to better differentiate the prognosis
of the disease than more surgically oriented scores do. Although the scoring systems did not allow any clinical decision,
they should be used to help better compare patients treated in different institutions. The observation of the minor relevance
of bacteriology and the superiority of general sepsis scores agrees with the fact that pre-existing septic organ dysfunction
and pre-existing comorbidity are the main determinants of mortality. Treatment: Surgical therapy focuses on the control of the source of infection because it has been clearly shown that, without resolving
the source of infection, the prognosis remains poor. Adjuvant surgical measures aim at the further reduction of the bacterial
load in the peritoneal cavity. Planned relaparotomy, relaparotomy on demand, and continuous closed peritoneal lavage are used.
Results: Clinical results proved these methods to be equally effective although pathophysiological considerations favour closed peritoneal
lavage. Conclusion: Summarising the available data, we need a more sophisticated understanding of the pathophysiology of the peritonitis, and
well-designed clinical studies are necessary to define the optimal surgical treatment modalities.
Received: 27 November 1997 相似文献
84.
Sacral insufficiency fractures develop over a period of time and show time-dependent changes. We report on 15 CT examinations of 5 patients with early-stage insufficiency fractures of the sacrum. In 4 patients only irregular sclerosis without distinct fracture lines was present in 7 of 8 fractures. Of these 4 patients; 3 exhibited intraosseous gas inclusions in a ventral part of a lateral mass; 5 of 8 fractures disclosed a ventral cortical break. When distinct fracture lines had developed in 1 patient, intraosseous vacuum phenomenon had disappeared. Fracture lines evolve over weeks to months and show central bone absorption. The fractures can heal as demonstrated in 4 of 6 fractures in 3 patients, can persist over 1 year without significant changes or can progress to pseudoarthrosis with bone destruction similar to neuropathic joint disease. Intraosseous vacuum phenomena can persist to this stage. Intraosseous vacuum phenomenon is recognized as a potential finding in the early stage of sacral insufficiency fracture, which also is true for irregular sclerosis and ventral cortical disruption.
Correspondence to: A. Stäbler 相似文献
85.
86.
87.
Dose response, coasting, and differential fiber vulnerability in human toxic neuropathy: a prospective study of pyridoxine neurotoxicity. 总被引:6,自引:0,他引:6
We administered either 1 or 3 g/d of pyridoxine (vitamin B6) to five healthy volunteers and repeatedly followed serum pyridoxal phosphate levels, clinical symptoms and signs, quantitative sensory thresholds (QSTs), and sural nerve electrophysiology. Pyridoxine was discontinued at the first sign of either clinical or laboratory abnormality. In all subjects, sensory symptoms and QST abnormalities occurred concurrently. Subjects receiving higher doses became symptomatic earlier than low-dose subjects. Elevation of thermal QSTs preceded or exceeded that for vibration in the three low-dose subjects; vibration and thermal QST became abnormal simultaneously in the higher-dose subjects. A reduction in the amplitude of the sural sensory potential lagged behind QST changes in two of three subjects. Symptoms continued to progress ("coasting") for 2 to 3 weeks despite stopping pyridoxine administration and the return of serum pyridoxal phosphate levels to normal. This study suggests that (1) there is a clear dose-percent relationship for pyridoxine-induced neuropathy, (2) QST is a sensitive measurement for detecting early peripheral neuropathy; QST abnormalities may precede changes in nerve conduction studies, (3) coasting appears unrelated to persistently elevated blood levels of the toxin, and (4) a dose-dependent vulnerability may exist among nerve fibers of different caliber when exposed to an axonal toxin, such as pyridoxine. 相似文献
88.
It has been postulated that spontaneous pneumothoraces (SP) develop because of rupture of subpleural blebs, and that atmospheric pressure changes (delta AP) may be contributory. A 5-year retrospective analysis of SP admissions was carried out to determine if delta AP do play a role in SP development. Using a 36-yr record of hourly delta AP, a normative background for delta AP was constructed. A fall in AP below the fifth, or a rise above the ninety-fifth percentile during these time periods, was classed as "unusual." Atmospheric pressure changes in the 4 days prior to SP were analyzed. The expected frequency of SP occurring by chance, if no relationship to delta AP existed, was also calculated. A total of 192 cases of SP was analyzed. Traumatic pneumothoraces were excluded. The majority of cases (72%) had been exposed to at least one "unusual" delta AP in the 4 days prior to onset of symptoms. Among those with four or more "unusual" exposures, SP occurrence was significantly more frequent than expected by chance alone (p less than 10(-10]. A strong positive association between delta AP and SP was not found in all cases, as delta AP are unlikely to be the only causative factor for SP. This finding of a relationship with ambient pressure changes lends support to the theory that SP develop as a result of rupture of subpleural blebs. 相似文献
89.
E Irschick K Miller M Berger D Sch?nitzer J Koller H Wagner W G?ttinger C Huber 《Transplantation》1989,48(6):986-990
Transplantation of unmatched allogeneic corneas into highly vascularized recipient eyes under the cover of short-term immunosuppression with cyclosporine enables permanent engraftment. The aim of this study was to further elucidate the mechanism(s) underlying this tolerant state. In eight "high-risk" cornea recipients the clone sizes of donor-specific and third-party reactive cytotoxic T cell precursors were assessed by limiting dilution analyses before and at three and six months after transplantation. Acquired allograft tolerance in these patients was not accompanied by clonal reduction of donor-specific CTL-p, whereas in the case of an irreversible rejection the donor-specific CTL pool size was significantly enlarged. This donor-specific CTL-p increase could already be seen two months before clinical manifestation. These patterns differed from that of tolerant renal transplant patients, in whom marked and donor-specific reduction of CTL-p was observed. During rejection identical patterns with increasing donor-specific CTL-p frequencies were seen in both groups of patients. We conclude that induction of tolerance by short-term CsA to unmatched cornea grafts is not caused by clonal reduction of the effector precursor cell pool. 相似文献
90.
Evaluation of long-term safety of the anti-IgE antibody, omalizumab, in children with allergic asthma. 总被引:8,自引:0,他引:8
William Berger Niroo Gupta Margaret McAlary Angel Fowler-Taylor 《Annals of allergy, asthma & immunology》2003,91(2):182-188
OBJECTIVE: To evaluate the long-term effects of the anti-IgE antibody omalizumab in children with asthma. METHODS: This was a 28-week, double-blind, randomized, placebo-controlled trial with a 24-week open-label extension. In the core trial 225 children (ages 6 to 12 years) with moderate-to-severe allergic asthma requiring inhaled beclomethasone dipropionate (BDP) received omalizumab every 2 or 4 weeks, and 109 received placebo. BDP dosage was stable for weeks 1 to 16, then reduced during weeks 17 to 24 using strict safety criteria. The lowest dose for optimal asthma control was maintained for 4 more weeks. During the 24-week extension, all patients (n = 309) received open-label omalizumab in addition to other asthma medications. One-year safety data were analyzed. RESULTS: The incidence of adverse events in patients treated with omalizumab for 52 weeks was similar to those treated for 28 weeks in the core trial, which was generally comparable with placebo. In the 52-week omalizumab group, upper respiratory tract infection and headache were the most frequently reported adverse events (47.1% and 42.7%, respectively). Eleven patients (4.9%) reported urticaria, which resolved spontaneously or with antihistamine, except for 1 patient who was discontinued because of severe urticaria. No anaphylactic reactions or adverse events suggestive of serum sickness or immune complex formation occurred. No anti-omalizumab antibodies were detected in any of the children. There is no evidence that new or more serious adverse events occur with long-term omalizumab treatment. CONCLUSIONS: Long-term treatment with omalizumab is safe and well tolerated in children with allergic asthma. 相似文献