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111.
Küpker W Schwinger E Hiort O Ludwig M Nikolettos N Schlegel PN Diedrich K 《Human reproduction (Oxford, England)》1999,14(Z1):24-37
Major principles of genetic failures, chromosomal alterations and the most common syndromes associated with male subfertility should be taken into account before medical therapy and sophisticated techniques of assisted fertilization are applied to help a couple conceive. This review addresses the most common genetic reasons for male subfertility or infertility with special regard to the importance for the clinical work-up in daily routine and the potential risks for the conceptus. 相似文献
112.
Arens S Kraft C Schlegel U Printzen G Perren SM Hansis M 《Archives of orthopaedic and trauma surgery》1999,119(1-2):82-85
Resistance to local infection after fracture fixation with plate osteosynthesis may be influenced by the implantation technique.
It is known that the extent of the surgical approach to the bone can compromise the local defence capacity. We have investigated
susceptibility to infection after a local bacterial challenge in rabbit tibiae using either the open surgical approach for
‘biological’ internal fixation of standard 2.0 dynamic compression plates or the method of minimally invasive plate osteosynthesis
(MIPO), a percutaneous, tunnelling insertion technique preserving the integrity of the overlying soft tissue. After the wounds
had been closed, various concentrations of Staphylococcus aureus were injected in the direct vicinity of the implants. The infection rate for the open surgical technique was 38.5% and that
for the MIPO technique, 25%. This difference is not statistically significant (P > 0.05) suggesting that resistance to local infection associated with the MIPO method is at least equivalent to the open
approach for plate osteosynthesis.
Received: 22 January 1998 相似文献
113.
MRI findings in Hirayama’s disease: flexion-induced cervical myelopathy or intrinsic motor neuron disease? 总被引:6,自引:0,他引:6
Schröder R Keller E Flacke S Schmidt S Pohl C Klockgether T Schlegel U 《Journal of neurology》1999,246(11):1069-1074
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
114.
L-701,324, a selective antagonist at the glycine site of the NMDA receptor, counteracts haloperidol-induced muscle rigidity in rats 总被引:1,自引:1,他引:0
J. Konieczny Krystyna Ossowska Gert Schulze Helmut Coper Stanislaw Wolfarth 《Psychopharmacology》1999,143(3):235-243
Rationale: It has recently been suggested that the overactivity of glutamatergic neurotransmission may contribute to the pathophysiology
of Parkinson’s disease. Therefore, a search for new compounds which block glutamatergic receptors and show antiparkinsonian
properties in animal models of this disease seems to be justified. Objective: The aim of this study was to determine whether L-701,324 [7-chloro-4-hydroxy-3(3-phenoxy) phenylquinoline-2-(H)-one], a selective
and full antagonist at the glycine site of the NMDA receptor, counteracts parkinsonian-like muscle rigidity and catalepsy
induced by haloperidol in rats. Methods: The muscle tone was measured as the resistance developed to passive flexion and extension of the hind limb. Electromyographic
(EMG) activity was additionally recorded in the gastrocnemius and tibialis anterior muscles. Results: L-701,324 (2.5–40 mg/kg IP) dose-dependently decreased the muscle tone enhanced by haloperidol (1–5 mg/kg IP). Likewise, the
haloperidol-enhanced resting EMG activity and the EMG reflex response to passive movements were diminished by lower and almost
abolished by higher doses of L-701,324. However, up to a dose of 20 mg/kg IP, L-701,324 did not influence haloperidol (0.5
mg/kg IP)-induced catalepsy. Moreover, L-701,324 (1.25–5 mg/kg IP) given alone or together with haloperidol (0.5–1 mg/kg IP)
disturbed rotarod performance. Gross observation of behaviour indicated that rats injected with L-701,324 in doses equal to
or higher than 5 mg/kg, alone or in combination with haloperidol, were markedly ataxic, i.e. rats showed signs of disturbed
balance and loss of control over their hind limbs. Conclusions: The present study suggests that L-701,324 exhibits a beneficial action in the animal model of parkinsonian rigidity, but not
that of parkinsonian akinesia. Nonetheless, this compound is not devoid of motor side-effects.
Received: 1 February 1998 / Final version: 20 October 1998 相似文献
115.
Summary Motor activity of rats was recorded following bilateral injections of GABA and the two GABA analogues gammahydroxybutyric acid (GHBA) and baclofen into the nucleus accumbens. GABA produced a shortlasting hypoactivity and this effect was potentiated by the GABA transaminase inhibitor aminooxyacetic acid (AOAA). More pronounced hypoactivities were caused by GHBA and baclofen. The hypoactivity was followed by hyperactivity after GHBA, baclofen and, to a small extent, after AOAA plus GABA. Systemic treatment with GHBA and GABA also suppressed motor activity and GHBA caused a subsequent hyperactivity. Small doses of GABA and particularly GHBA injected into the nucleus accumbens caused an increase in motor activity without the preceding decrease, especially when the rats were habituated to the environment. The effects appeared specific since no or only small changes in motor activity were induced by carnitine and betahydroxybutyric acid, structurally related to GABA and GHBA, respectively. Furthermore, the motor activity was stimulated by local treatment with the GABA receptor blocking agent picrotoxin, but not by strychnine or pentylenetetrazole. GHBA and GABA inhibited the apomorphine-induced activity of reserpine-treated rats indicating that these compounds stimulate GABA receptors beyond the dopamine synapses. The motor activity was depressed by GHBA and GABA given into the rostral and intermediate neostriatum and into the globus pallidus and, to a smaller extent, when given into the caudal neostriatum. The stimulatory effect of GHBA or picrotoxin was less, pronounced after local application to the globus pallidus or the neostriatum than when applied to the nucleus accumbens. The increased motor activity by GHBA, baclofen and GABA might be due to stimulation of GABA autoreceptors in the nucleus accumbens. The decreased motor activity might be evoked by stimulation of postsynaptic GABA receptors in the nucleus accumbens but a similar action in the corpus striatum might contribute.Part of the data was presented at the symposium on Interactions Among Putative Transmitters in the Brain held at the Mario Negri Institute, Milan, Italy on October 26–28, 1976 相似文献
116.
Wolfram Sterry Helmut Pullman Gerd-Klaus Steigleder 《Archives of dermatological research》1981,270(3):285-290
Summary To obtain information about the role of local proliferation in the pathogenesis of dermal infiltrate in malignant cutaneous lymphomas, we determined the percentage of 3H-thymidine-labeled infiltrating cells (3H-index).A linear correlation was found between proliferative activity and clinical stage in mycosis fungoides, i.e., the 3H-index is moderately elevated in stage I and high in stage III.The 3H-index is within normal range in dermal infiltrate of Sézary syndrome, diffuse lymphocytic lymphoma, as well as in lymphocytoma benigna cutis.In parapsoriasis en plaques two groups can be distinguished: in the smallplaque variant (chronic superficial dermatitis) the 3H-index is low, whereas the large-plaque variant (prereticulotic poikiloderma) shows strong proliferative activity.Thus, determination of proliferative activity seems to give new insights into the pathogenesis of dermal infiltrate in cutaneous lymphomas.Zusammenfassung Um die Bedeutung der lokalen Zellproliferation im dermalen Infiltrat bei cutanen malignen Lymphomen zu untersuchen, bestimmten wir den Prozentsatz der 3H-Thymidin-markierten Infiltratzellen (3H-Index.Zwischen dem klinischen Stadium der Mycosis fungoides und der Proliferationsaktivität des dermalen Infiltrats besteht eine lineare Beziehung; im Stadium I ist die Proliferation niedrig, im Stadium III sehr hoch.Nicht erhöht ist der 3H-Index im dermalen Infiltrat beim Sézary-Syndrom, diffusen lymphocytischen Lymphom sowie bei Lymphocytoma benigna cutis.Bei der Parapsoriasis en plaques müssen zwei Formen unterschieden werden: bei der kleinfleckigen Form (chronic superficial dermatitis) ist der 3H-Index niedrig, während die großfleckige Form (Präretikulotisches Poikiloderm) eine starke Proliferationsaktivität aufweist.Die Untersuchung des Proliferationsverhaltens gibt neue Einblicke in die Pathogenese des dermalen Infiltrats cutaner Lymphome. 相似文献
117.
Rüdiger Burkard Klaus Peter Kaiser Helmut Wieler Peter Klawki Axel Linkamp Lutz Mittelbach Thomas Göller 《Neurosurgical review》1992,15(4):265-273
Single photon emission computed tomography (SPECT) with thallium-201-chloride (201TI) was used in 22 patients to assess the grade of malignancy of brain tumors.Low- and high-grade malignant gliomas could be well differentiated by calculating the Grade Index (GI), i.e., 201TI uptake in the tumor area relative to a contralateral brain region. Low-grade gliomas (WHO-grade I–II) usually showed a GI of <1.5. Tumors classified histologically as high-grade malignant (WHO-grade III–IV) had GI values greater than 1.42 and a mean value of 1.89.Until labelled amino-acid tracers for gamma-cameras become commercially available, thallium-201 brain-SPECT can provide an independent and complementary method to CT/MRI for the differential diagnosis of grading of brain tumors. This simple technique can help to reduce sampling errors during needle biopsies of brain tumors, particularly of high-grade lesions incorrectly graded as low-grade tumors due to inadequate biopsy material. In addition, pre- and post-therapy studies can influence the strategy of therapy itself and allow an early detection of recurrences. 相似文献
118.
Kluger's Fixateur Interne proved to be an excellent tool not only in spinal trauma for repositioning of impacted fractures and transpedicular stabilization of the dorsal column but also in other forms of thoracic or lumbar instability.After spinal tumor excision from a dorsal approach and vertebral replacement with methylmethacrylate additional stability through dorsal fixation was achieved with this device.Spondylodiscitis, symptomatic spondylolisthesis, spinal instability from degenerative disc disease as well as nonunion following previous surgery could be cured using Kluger's internal fixation. Rare complications, i.e. from broken screws or rods (5%) caused no problems, but some patients required a second operation for readjustment of malpositioned screws which were causing pain or neurological deficit. 相似文献
119.
Volker B. Fiedler Sybylle Buchheim Helmut Göbel Rolf-Eberhard Nitz 《Naunyn-Schmiedeberg's archives of pharmacology》1982,321(4):314-320
Summary The effects of i.v. molsidomine and dopamine infusion on mean haemodynamic changes, myocardial oxygen consumption (pressure-rate-product), and ultimate infarct size were studied in pentobarbital-anaesthetized, open-chest dogs and compared to those occurring in dogs receiving saline infusion. Either agent was administered in a separate setting. Haemodynamic variables and oxygen consumption were determined during a 6-h period after ligation of the left anterior descending coronary artery and collected at 1-h intervals. Infarct size was determined by post-mortem nitroblue tetrazolium stain of intracellular lactic dehydrogenase enzymes. Coronary artery ligation during saline infusion (n=8) resulted in decreased blood pressure and cardiac output, whereas heart rate, systemic peripheral resistance, end-diastolic filling pressure and myocardial oxygen consumption increased. Infarct size amounted to 24.2±3.2% (i. e., 23.8±3.1 g) of left ventricular mass. Infusion of 1.4 g/kg/min molsidomine (n=8) produced significant fall of blood pressure, cardiac output, filling pressure and oxygen consumption while heart rate and peripheral resistance were unaffected. The infarct volume was reduced to 49% (P<0.01) of that observed in saline controls. The administration of 3 g/kg/min dopamine (n=8) elevated blood pressure and cardiac output initially with a subsequent reduction of either parameter. Arteriolar vascular resistance and oxygen consumption increased but filling pressure remained unchanged. Infarct size was not different from saline controls. Infusion of 6 g/kg/min dopamine, however, significantly increased blood pressure, heart rate, and peripheral resistance. Cardiac output and filling pressure fell and myocardial oxygen consumption rose. The histochemically measured final infarct was reduced to 13.5±1.8% of left ventricle (i. e., 16.2±2.2 g, P<0.05 vs saline control), but the hearts were edematous and haemorrhagic. Therapy with molsidomine appears promising in the treatment of clinical myocardial infarction with haemodynamic sequellae. The safe use of therapy with higher dopamine doses in patients with acute myocardial infarction, however, awaits further investigation.Part of the dopamine experiments were done at Bayer AG, Institut für Pharmakologie 相似文献
120.
Pignatelli Brigitte; Bereziat Jean-Claude; Descotes Gerard; Bartsch Helmut 《Carcinogenesis》1982,3(9):1045-1049
Measurements were made of the effects of phenolic compounds,some of which are present in the human diet, on the nitrosationof proline by nitrite to give N-nitrosoproline (NPRO). In vitro,resorcinol, catechin, p-nitrosophenol and phenol were catalystsand chlorogenic acid an inhibitor; guaiacol showed a marginalcatalytic effect. Both the catalytic and the inhibiting effectswere dependent on pH and on the concentration of phenolic compounds;catalysis by resorcinol and catechin was increased at optimalratios of [nitrite]: [phenolic compound]. Endogenous nitrosationwas examined in vivo by co-administration of nitrite, prolineand a phenolic compound to rats and by monitoring the amountof NPRO excreted in the urine. Under similar experimental conditions,the catalytic effects observed in vivo decreased in the sameorder as those observed in vitro: resorcinol > p-nitrosophenol> catechin > phenol guaiacol; chlorogenic acid acted asan inhibitor. Catalysis and inhibition of N-nitrosation in ratsin vivo appears to occur via mechanisms similar to those invitro, although the effects in vivo were smaller. The implicationsof our findings for the endogenous formation of N-nitroso compoundsand for variations in exposure due to different dietary constituentsin humans are discussed. 相似文献