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101.
Invertebrate skeletal muscle contraction is regulated by calcium influx through voltage-dependent calcium channels in the sarcolemmal membrane. In present study we investigated the effects of nitric oxide (NO) donors on calcium currents of single skeletal muscle fibres from the marine isopod, Idotea baltica, using two-electrode voltage clamp recording techniques. The NO donors, S-nitrosocysteine, S-nitroso-N-acetyl-penicillamine or hydroxylamine reversibly increased calcium inward currents in a time dependent manner. The increase of the current was prevented by methylene blue. Our experiments suggest that NO increases calcium inward currents. NO, by acting on calcium ion channels in the sarcolemmal membrane, therefore, may directly be involved in the modulation of muscle contraction.  相似文献   
102.
Obstructive pulmonary diseases are diverse with an extensive differential diagnosis. Most cases can be diagnosed after a systematic evaluation that includes detailed history, physical examination, routine laboratory testing, radiologic and pulmonary physiologic tests. More specific studies are indicated only in a few patients.  相似文献   
103.
Tinnitus is one of the most important symptoms in neurootology after vertigo, nausea, and hearing loss. In most cases, the origin of the tinnitus remains inexplicable. Well-known, however, is that tinnitus may arise in any part of the hearing pathway (i.e., both within the cochlea receptor and in the temporal lobe and projections). Tinnitus also is associated frequently with vertigo, nausea and hearing loss. An age predominance exists, with tinnitus more common among those older than 40 years. From this starting point, a great demand exists today for new ideas and developments in the diagnosis and treatment of tinnitus.  相似文献   
104.
In comparison with laryngeal voice, substitute voice after laryngectomy is characterized by restricted aero-acoustic properties. Until now, an objective means of prosodic differences between substitute and normal voices does not exist. In a pilot study, we applied an automatic prosody analysis module to 18 speech samples of laryngectomees (age: 64.2 ± 8.3 years) and 18 recordings of normal speakers of the same age (65.4 ± 7.6 years). Ninety-five different features per word based upon the speech energy, fundamental frequency F0 and duration measures on words, pauses and voiced/voiceless sections were measured. These reflect aspects of loudness, pitch and articulation rate. Subjective evaluation of the 18 patients’ voices was performed by a panel of five experts on the criteria “noise”, “speech effort”, “roughness”, “intelligibility”, “match of breath and sense units” and “overall quality”. These ratings were compared to the automatically computed features. Several of them could be identified being twice as high for the laryngectomees compared to the normal speakers, and vice versa. Comparing the evaluation data of the human experts and the automatic rating, correlation coefficients of up to 0.84 were measured. The automatic analysis serves as a good means to objectify and quantify the global speech outcome of laryngectomees. Even better results are expected when both the computation of the features and the comparison method to the human ratings will have been revised and adapted to the special properties of the substitute voices.  相似文献   
105.
The aim of the present study was to examine the effect of galanin on group III and IV afferent nerve fibres (n = 53) innervating normal and acutely inflamed knee joints in rats. They responded to local mechanical stimulation, movements of the joint and i.a. injections of KCl close to the joint. Single i.a. bolus injections of galanin (0.1 mM, 0.2 mL) caused no direct responses of the units. In normal and acutely inflamed joints, about half of the units did not change the responses to knee joint rotation. A significant reduction of the responses to noxious movements was found in approximately 40% of the units reaching a mean value of 57% in normal joints and 70% in inflamed joints compared with control movements. In approximately 10% the responses increased to 143% in normal joints and 120% in inflamed joints. Injection of a galanin receptor antagonist (M35) doubled the responses to noxious movements in 36% of the units in normal joints and reduced it in 18% to 86% of the control movements, indicating a tonic release and influence on the mechanosensitivity of a proportion of primary afferents by galanin. In conclusion, these data further support the hypothesis that the mechanosensitivity of fine afferent nerve fibres is regulated by a mixture of different substances being released into the innervated tissue. Besides the action of several pro-inflammatory peptides there seems to exist a tonic inhibitory system.  相似文献   
106.
B.N. Landis MD  T. Just 《HNO》2010,58(7):650-655
Clinically, taste disorders are less frequent than smell disorders. Nevertheless, they are very distressing to the concerned patients. Unfortunately, the underlying causes are not always found and a majority of patients are considered idiopathic dysgeusia cases. Besides this taste disorder of unknown origin, medication side effects and surgical injuries are the most frequent origins of dysgeusia. Despite recent, impressive molecular biological and physiological insight into the taste system, few clinical improvements have been achieved. Consequently, curative treatment options remain sparse.  相似文献   
107.
108.
Objective: Records of metric data of birth, serve not only the medical needs of the newborn baby, but are also indicators to assess the status of public health.

Methods: This is a retrospective study of 4946 newborns (singleton: 2508 boys and 2365 girls) born in 1989 and in 2009 at the Department of Obstetrics and Gynaecology of the University of Szeged. We aimed as to compare and map the metrical changes over 20 years, and to describe the averages of four body parameters of the normal birth weight (2500–4000?g) subgroup (3993 singleton babies) in both years. Statistical analysis was performed with SPSS 17.0.

Results: In 1989, the mean birth weight was 3223.770?±?559.595?g, birth length 49.551?±?2.729?cm, chest circumference 32.181?±?2.231?cm, and head circumference 34.122?±?1.688?cm. In 2009, the birth weight was 3309.673?±?582.630?g, birth length 49.515?±?2.658?cm, chest circumference 32.736?±?2.392?cm and head circumference 33.854?±?1.768?cm. The mean birth weight, chest circumference and the maximum value of birth weight have thus increased. The mean maternal age shifted to 30.21?±?4.863 years, which is an increase of 3.57 years in 20 years.

Conclusion: The body parameters of newborns changed significantly between 1989 and 2009. As underlying causes changes in eating habits and lifestyle of the mother are to be mentioned.  相似文献   
109.
C3 from Clostridium botulinum (C3) specifically modifies Rho GTPases RhoA, RhoB, and RhoC by mono-ADP-ribosylation. The confined substrate profile of C3 is the basis for its use as pharmacological tool in cell biology to study cellular functions of Rho GTPases. Although C3 exoenzyme does not possess a cell-binding/-translocation domain, C3 is taken up by intact cells via an unknown mechanism. In the present work, binding of C3 to the hippocampus-derived HT22 cells and J774A.1 macrophages was characterized. C3 bound concentration-dependent to HT22 and J774A.1 cells. Pronase treatment of intact cells significantly reduced both C3 binding and C3 cell entry. Removal of sugar residues by glycosidase F treatment resulted in an increased binding of C3, but a reduced cell entry. To explore the involvement of phosphorylation in the binding process of C3, intact HT22 and J774A.1 cells were pre-treated with vanadate prior to incubation with C3. Inhibition of de-phosphorylation by vanadate resulted in an increased binding of C3. To differentiate between intracellular and extracellular phosphorylation, intact cells were treated with CIP (calf intestine phosphatase) to remove extracellular phosphate residues. The removal of phosphate residues resulted in a strong reduction in binding of C3 to cells. In sum, the C3 membranous binding partner is proteinaceous, and the glycosylation as well as the phosphorylation state is critical for efficient binding of C3.  相似文献   
110.
The in vitro metabolism of cyclosporin A (CsA) was investigated by rabbit liver microsomes in order to identify the form(s) of cytochrome P-450 responsible for its biotransformation. Metabolites including monohydroxy-, N-demethylated, dihydroxy- and dihydroxy-N-demethylated derivatives were detected and quantified by HPLC from incubates of liver microsomes, CsA, and NADPH. Kinetic data indicated that monohydroxy- and N-demethylated derivatives were first generated and then served as substrates for production of dihydroxylated derivatives. Liver microsomes from phenobarbital-, beta-naphthoflavone-, triacetyloleandomycin-, erythromycin-, or rifampicin-treated and untreated rabbits were investigated, but only microsomes from animals treated with macrolide antibiotics (specific inducers of form P-450 3c) exhibited a type I binding spectrum upon CsA addition (Ks = 1.5 +/- 0.5 microM) and extensively metabolized the drug to all groups of derivatives (Km = 5.0 +/- 0.5 microM, Vmax = 1.0 +/- 0.2 nmol/mg/min). A linear correlation existed between CsA oxidase activity and P-450 3c specific content. Antibodies to P-450 3c strongly inhibited CsA oxidase activity of microsomes from macrolide antibiotic-induced animals, whereas antibodies to other forms, including P-450 2, 3b, 4, and 6, did not. When highly purified forms of P-450, including P-450 2, 3b, 3c, and 4, were assayed in a reconstituted system, only P-450 3c exhibited type I binding spectrum upon CsA addition (Ks = 1.4 +/- 0.5 microM) and extensively metabolized the drug to all derivatives. We conclude that the macrolide antibiotic-inducible form P-450 3c (or P-450 3c related from(s)) is responsible for the major part of CsA metabolism by rabbit liver microsomes.  相似文献   
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