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961.
962.
Viktoria Werkström Lars Ny Katarina Persson K.-E. Andersson 《Naunyn-Schmiedeberg's archives of pharmacology》1997,356(2):151-158
Neuronal regulation of smooth muscle tone in the female pig urethra has mainly been studied in vitro using electrical field
stimulation (EFS) of nerves. Excitatory control is considered to be exerted by released noradrenaline, whereas inhibitory
control is non-adrenergic non-cholinergic (NANC), and mediated by nitric oxide (NO), and an as yet unidentified agent. We
investigated the functional and morphological effects of α-latrotoxin (αLTX), a spider neurotoxin believed to cause massive
release of vesicle-stored neurotransmitters, on spontaneously developed urethral smooth muscle tone. The effects were compared
to those of EFS and high potassium. In the presence of the NO-synthesis inhibitor Nω-nitro-L-arginine (L-NOARG: 0.3 mM) both αLTX and EFS evoked contractions. After treatment with scopolamine and phentolamine,
no contraction was observed, and under these conditions αLTX and EFS induced relaxation. At low frequencies (<12 Hz), the
EFS-induced relaxations were rapid, whereas at higher frequencies (>12 Hz), they were biphasic, consisting of a rapid first
phase followed by a more long-lasting second phase. L-NOARG abolished the relaxations at low frequencies, as well as the first
phase of the biphasic relaxation. The second phase was not affected by treatment with L-NOARG, but 0.1 μM ω-conotoxin GVIA,
blocker of N-type voltage-operated calcium- channels (VOCCs), markedly reduced or abolished the response. In the presence
of L-NOARG or ω-conotoxin GVIA, the αLTX-induced relaxation was significantly decreased, and the combination of L-NOARG and
ω-conotoxin GVIA further reduced or abolished the relaxation. In preparationstreated with tetrodotoxin or scorpion venom,
believed to inactivate nerves by acting on sodium channels, αLTX and EFS had no effects. αLTX-induced relaxation was not associated
with changes in cyclic GMP or cyclic AMP content. High (80 mM) potassium solution induced a triphasic response of the preparation.
A transient relaxation was followed by a restoration of tone, and then by a persistent relaxation. The persistent relaxation
was slightly reduced by scorpion venom or L-NOARG, but reduced by 50% by a combination of L-NOARG and ω-conotoxin GVIA. Ultrastructural
analysis of the urethral circular smooth muscle layer revealed a moderate amount of nerve profiles supplying the smooth muscle.
In control preparations, the nerve profiles contained both small synaptic vesicles and large dense core vesicles. αLTX caused
a major loss of both types of vesicle. The present data suggest that αLTX has the ability to release not only adrenergic and
cholinergic transmitters, but also NANC mediators of relaxation, including NO, from nerve terminals in the urethra.
Received: 13 January 1997 / Accepted: 17 April 1997 相似文献
963.
Alexander Goldberg Ursula Schlötzer-Schrehardt Theo Seiler 《International ophthalmology》1997,21(3):117-120
We report the first case of a unilateral microcysticMeesmann‘s epithelial dystrophy, observed in the left cornea of a 43-year-old
patient. The diagnosis was verified histologically by the unilateral occurrence of a ’peculiar substance‘ within epithelial
cysts and within the cytoplasm of the corneal epithelial cells. In an attempt to resolve thepatient‘s frequent corneal erosions,
we performed an autologous stem cell transplantation from the non-involved right eye. The results are, so far, satisfactory.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
964.
965.
Norbert Rilinger Johannes Görich Reinhard Scharrer-Pamler Jochen Vogel Reinhard Tomczak Elmar Merkle Roman Sokiranski Hans-Jürgen Brambs 《Cardiovascular and interventional radiology》1997,20(4):263-267
Purpose To evaluate the clinical results of percutaneous transluminal rotational atherectomy in the treatment of peripheral vascular
disease.
Methods Rotational atherectomy was performed in 39 patients aged 39–87 years (mean 66.6 years). A total of 71 lesions (43 stenoses
and 28 occlusions) were treated in 40 limbs. Additional balloon angioplasty was required in 54% of lesions. Fifteen patients
(37.5%) presented in Fontaine stage II, 10 patients (25%) in Fontaine stage III and 15 patients (37.5%) in Fontaine stage
IV. Rotational atherectomy at 750 rpm was carried out over a 0.014-inch guidewire with continuous aspiration into a vacuum,
bottle. Follow-up angiography and color flow Doppler examinations were performed in 22 patients (23 limbs) after a mean period
of 6 months (range 2–14 months)
Results There was one primary technical failure. In 36 of 40 lesions there was a good angiographic result with residual stenoses in
less than 30%. In 70 lesions treated by rotational atherectomy, however, 54% showed residual stenoses of 30%–50% and these
cases required additional balloon angioplasty. The mean ankle-brachial index improved significantly (p<0.001), from 0.49 before the procedure to 1.01 after the procedure. A single distal embolus, related to primary recanalization,
occurred and there were two large inguinal hematomas. Cumulative clinical patency after 6 months was 83.8% and cumulative
angiographic patency after 6 months was 79.1%.
Conclusion Percutaneous rotational atherectomy is a promising approach for the treatment of chronic peripheral vascular disease. Further
prospective, randomized studies are necessary to compare percutaneous transluminal angioplasty with this new technical approach. 相似文献
966.
967.
Isha Tyagi H. C. Taneja 《Indian journal of otolaryngology and head and neck surgery》1997,49(1):51-53
A 50-year old male presented with swollen right eyelids, bleeding per nostrils and a vague left post-auricular swelling for 4 months. Posterior rhinoscopy revealed one pinkish polypoidal mass in the posterior nare and roof of nasopharynx. FNAC from the post-auricular swelling suggested metastatic undifferentiated carcinoma. Incisional biopsy was done form the nasopharynx and histopathological examination proved it to be a malignant paraganglioma. The case is reported for its rarity. 相似文献
968.
Zusammenfassung In diesem Reviewartikel wird die sozial- und verhaltenswissenschaftliche Interventionsliteratur der letzten 20 Jahre im
deutschsprachigen Raum kritisch resümiert. Es werden nur kontrollierte Studien mit ad?quater Erhebungsmethodologie berücksichtigt.
Was Interventionen im kognitiven Bereich betrifft, so belegen die Arbeiten deutlich positive Trainingseffekte. Allerdings
zeigen Studien auch die Grenzen der kognitiven Plastizit?t in deutlicher Weise auf. Anhand eines weiten Bündels von Studien
zeigt sich die Potenz von Interventionen zur Bewahrung bzw. Wiedererlangung der Selbst?ndigkeit im Alltag, zur Erh?hung der
sozialen Aktivit?t und des subjektiven Wohlbefindens. Ebenso finden sich positive Effekte im Bereich des Selbstkonzepts, der
personalen Kontrolle und des Attributionsstils. Eine allgemeine Diskussion dieser Befunde mündet in Vorschl?ge für zukünftige
Forschungspriorit?en.
Eingegangen: 10. November 1997, Akzeptiert: 22. Januar 1998 相似文献
969.
Reliability of a Store Observation Tool in Measuring Availability of Alcohol and Selected Foods 总被引:1,自引:0,他引:1
Deborah A. Cohen Diane Schoeff Thomas A. Farley Ricky Bluthenthal Richard Scribner Adrian Overton 《Journal of urban health》2007,84(6):807-813
Alcohol and food items can compromise or contribute to health, depending on the quantity and frequency with which they are
consumed. How much people consume may be influenced by product availability and promotion in local retail stores. We developed
and tested an observational tool to objectively measure in-store availability and promotion of alcoholic beverages and selected
food items that have an impact on health. Trained observers visited 51 alcohol outlets in Los Angeles and southeastern Louisiana.
Using a standardized instrument, two independent observations were conducted documenting the type of outlet, the availability
and shelf space for alcoholic beverages and selected food items, the purchase price of standard brands, the placement of beer
and malt liquor, and the amount of in-store alcohol advertising. Reliability of the instrument was excellent for measures
of item availability, shelf space, and placement of malt liquor. Reliability was lower for alcohol advertising, beer placement,
and items that measured the “least price” of apples and oranges. The average kappa was 0.87 for categorical items and the
average intraclass correlation coefficient was 0.83 for continuous items. Overall, systematic observation of the availability
and promotion of alcoholic beverages and food items was feasible, acceptable, and reliable. Measurement tools such as the
one we evaluated should be useful in studies of the impact of availability of food and beverages on consumption and on health
outcomes. 相似文献
970.