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1.
To have some insight into the mechanical interplay between the parasternal intercostal and triangularis sterni muscles during breathing, we have examined the isometric contractile properties of these two muscles in the dog. Using piezoelectric crystals, we have also measured the respiratory changes in muscle length in eight spontaneously breathing animals in the supine posture, and we have compared the in situ relaxation length (Lr) of these two muscles to their respective in vitro optimal force-producing length (Lo). The triangularis sterni and parasternal intercostals had similar isometric twitch, force-frequency, and length-tension characteristics. These two muscles, therefore, are intrinsically similar. In supine dogs, however, they operate on quite distinct segments of their length-tension curve. Whereas Lr for the parasternals corresponded to 117% Lo, Lr for the triangularis sterni was only 75% Lo. This suggests that the triangularis sterni in supine dogs operates on a poorly advantageous portion of its length-tension curve. However, shortening of the parasternals during inspiration causes considerable passive distension of the muscle. As a result, the triangularis sterni is much closer to its optimal length when it starts contracting in early expiration. 相似文献
2.
B. Farkas 《European Surgery》1989,2(1):15-17
Zusammenfassung Bericht über ?dintraoperative maschinelle autotransfusion?, kombiniert mit ?pr?operativer plasmapherese?. Mit maschineller
autotransfusion kann intraoperativer blutverlust durch rückführung eigener erythrozyten halbiert werden. In kombination mit
pr?operativer plasmapherese werden weitere fremdblutkonserven eingespart. übertragung von infektionskrankheiten und erzeugung
irregul?rer antikōrper kōnnen verhindert werden. Bei der derzeitigen AIDS-situation wird das infektionsrisiko auf null reduziert.
相似文献
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Detectable TNF levels in sera 33% of patients with sepsis following pancreatitis have been found. No correlation was observed between serum TNF concentration and the severity of illness. However, monocytes and granulocytes of septic patients exerted higher TNF-mediated cytotoxicity than leukocytes of normal blood donors. The in vitro TNF-producing capacity was also higher in the patients in the study group, and it decreased only before fatal outcoming of sepsis. Our results suggest that determination of the TNF-producing capacity of leukocytes might be more informative than measurement of the serum TNF level in the evaluation of the severity or prognosis of sepsis. 相似文献
5.
The effectiveness, side effects and serum FSH, LH, prolactin, estradiol and progesterone levels were monitored in 79 women taking Anteovin for a total of 506 cycles (mean 6.4 cycles). Anteovin is a biphasic oral contraceptive with 11 tablets containing 0.05 mg levonorgestrel and 0.05 mg ethinyl estradiol, and 10 tablets containing 0.125 mg levonorgestrel and 0.05 mg ethinyl estradiol. There were no pregnancies. 11 women dropped out because of hepatomegaly (1), bleeding disorder (3), gastric pain and nausea (1), breast pain (1), nausea and vomiting (1), and personal reasons (4). 10.3% of those continuing reported minor side effects. Menses occurred every 28 days for 3-5 days, with 2 cases of breakthrough bleeding but no oversuppression. Progesterone ranged from 1.5-2.0 nmol/1, estradiol varied between 68-93 pmol/1, LH stayed constant at 6.3-11 U/1, FSH remained at 5.8-6.8 U-1 without a peak, and prolactin levels were lower than those seen in control cycles. These hormone levels all resemble those observed in anovulatory cycles. This pill is especially suitable for teens and nulliparas. 相似文献
6.
Capsaicin (50 mg/kg s.c./25 μl) was administered to rats on the 2nd and 5th days after birth. The animals were raised, and from the age of 3 months the properties of the evoked activity were tested in the contralateral barrelfield. This neonatal capsaicin treatment was found to induce profound changes in the responsiveness of the barrel cortex in the adult rats: (1) the receptive field of the neurons in the Cl barrel was expanded; units within a particular barrel were driven by a significantly larger number of vibrissae than in the controls. (2) The rate of discharge evoked by the related vibrissa deflection was enhanced, while (3) the angular sensitivity of the neurons was decreased. (4) The most prominent change in cortical activity was observed by autoradiography: capsaicin-treated rats exhibited an enhanced labelling of different types of neurons throughout the hemisphere (surpassing the cortical representation of stimulated vibrissae). The present observations indicate that neonatal capsaicin affects the functional activity of the rat somatosensory cortex. It is suggested that unmyelinated sensory afferents play a role in the development of the rat somatosensory system. 相似文献
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8.
Gluing of sterile abdominal benign cyst walls with tissue adhesives (Tissucol) (preliminary report)]
The authors, endeavouring to stick the walls of percutaneously emptied cysts together had applied the two-component Tissucol fibrin glue in the treatment of abdominal and thoracic cysts. Their ten cases, however, may be considered only as preliminary experiences. It seems that the method can be recommended for an attempt to cease these formations in a fast and simple way. Nevertheless, this method must not be the subject of treatment in infected and malignant fluid collections, but seems successful in pancreatic pseudocysts, in spite of their higher proteolytic activity. 相似文献
9.
A 13-year-old girl with multiple genitourinary malformations, incomplete bladder exstrophy, urethral duplication with single bladder, septate vagina, and total urinary incontinence is presented. Prior to admission she had undergone surgery for teratoma and calculi of the bladder and partial fecal incontinence. A continent urinary diversion was done by bladder augmentation using a cecal-colonic segment and by surgical closure of the bladder neck. The distal end of the appendix was brought to the skin as an inconspicuous, easily catheterizable, watertight stoma, our modification of the Mitrofanoff procedure. Excision of the vaginal septum, creation of an introitus, and unification of the split clitoris improved the cosmetic appearance of the external genitalia and improved the outlook for a normal sexual life and pregnancy. 相似文献
10.