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41.
Lasers in Medical Science - Long-pulsed 1064-nm (LP1064) and 755-nm (LP755) lasers have been demonstrated as effective treatments for leg veins. However, few studies of these treatments on Asian...  相似文献   
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Huerta  S.  Tran  N.  Yi  B.  Pham  T. 《Hernia》2021,25(5):1289-1294
Hernia - The optimal approach for inguinal hernia repair in the obese remains elusive. Minimally invasive techniques show equivocal results compared to the open method. None of the current analyses...  相似文献   
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Background: Skeletal muscle lacerations are a relatively common injury. Compared with nonrepaired lacerations, surgically repaired muscle lacerations regenerate faster, develop less scar tissue, have a higher return to baseline strength, and have lower incidence of hematomas. Despite the benefits of repair, the optimal repair technique is still unknown. The purpose of this study was to examine the biomechanical properties of common muscle repair techniques to determine the optimal repair. Methods: Forty-two fusiform porcine muscle specimens were dissected and used for this study. Three suture techniques were used for comparative analysis: Figure-eight, Mason Allen, and Perimeter. Each muscle was transected and then repaired using one of the 3 techniques. Fourteen muscle-tendon specimens were prepared for each group and tested for tensile failure using a material testing system. Biomechanical properties, including peak failure point and stiffness, were compared for differences between the suture groups by 1-way analysis of variance. The average time per repair technique was also recorded. Results: The Perimeter technique showed a statistically significant higher peak failure point than the Mason Allen technique (P = .03). Both the Figure-eight (P = .047) and Perimeter techniques (P < .001) were significantly stiffer than the Mason Allen technique. The repair time was comparable across all 3 techniques. Conclusions: The Figure-eight and Perimeter repairs were found to be similar in peak failure point and stiffness, whereas the Mason Allen technique showed significantly lower stiffness and peak failure point. The Figure-eight was the quickest repair to perform. The Figure-eight technique may be strongly considered for muscle laceration repairs due to its simplicity and efficiency.  相似文献   
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Summary We have studied the sympathetic response to blockade of presynaptic 2-adrenoceptors in essential hypertension by measuring plasma concentrations of noradrenaline after a single oral dose of yohimbine, an 2-adrenoceptor antagonist.Mean baseline plasma noradrenaline and adrenaline concentrations were similar in the hypertensive and normotensive groups. Yohimbine (0.2 mg×kg–1 orally) caused a lesser increase in the plasma concentrations of noradrenaline in hypertensive patients (+67%) than in normotensive subjects (+178%) and a pressor response in hypertensive (but not in normotensive) patients.These results are consistent with an alteration in the balance of -adrenoceptors (for example presynaptic 2-adrenoceptor desensitization and post-synaptic 1-adrenoceptor hyper-responsiveness) which would help to develop and/or maintain arterial hypertension.  相似文献   
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  1. The α1-adrenoceptor population mediating contraction of caudal artery of rat has been characterized by using quantitative receptor pharmacology.
  2. Cumulative concentration-effect (E/[A]) curves to noradrenaline (NA) yielded a p[A]50 of 5.56±0.05 (n=16). Prazosin caused concentration-dependent, parallel, dextral shifts of E/[A] curves to NA yielding a pKb of 8.9 (Schild regression slope=1.0). RS-17053 (N-[2-(2-cyclopropyl methoxy phenoxy) ethyl]-5-chloro-α ,α-dimethyl -1H-indole- 3-ethanamine hydrochloride; 10–100 nM), a selective α1A-adrenoceptor antagonist, produced non-parallel, biphasic, dextral shifts of E/[A] curves to NA, suggesting the involvement of more than one α1-adrenoceptor subtype. Analysis of the high affinity component yielded an apparent pA2 value of 9.2±0.3.
  3. A-61603, a selective agonist at α1A adrenoceptors behaved as a full agonist relative to NA and yielded monophasic E/[A] curves with a p[A50] of 7.59±0.04 (n=15). Pretreatment of tissues with chloroethylclonidine (CEC; 100 μM for 20 min, followed by 40 min washout), which preferentially alkylates α1B- and α1D-adrenoceptors, did not alter E/[A] curves to A-61603. Prazosin (3–300 nM) caused concentration-dependent, parallel, dextral shifts of E/[A] curves to A-61603 yielding a pA2 estimate of 9.2±0.2.
  4. Experiments with α1-adrenoceptor antagonists of varying subtype selectivities (RS-17053, SNAP 5089, tamsulosin, 5-methylurapidil, BMY 7378, HV 723 and REC 15/2739) revealed parallel dextral shifts of E/[A] curves to A-61603. Schild regression analyses yielded pA2 estimates of 9.2, 9.3, 11.2, 9.0, 6.3, 8.7 and 10.0 for RS-17053, SNAP 5089, tamsulosin, 5-methylurapidil, BMY 7378, HV 723 and REC 15/2739, respectively, although deviations from unit slope (possibly reflecting a secondary involvement of another α1-adrenoceptor) hindered estimations of pKb for some antagonists. The antagonist affinity profile obtained reflects best that described for the α1A-adrenoceptor.
  5. In conclusion, caudal artery of rat contracts in response to NA via activation of at least two α1-adrenoceptor subtypes. One of these subtypes displays the pharmacology of the α1A-adrenoceptor, while the other remains to be defined. Use of the novel selective agonist, A-61603, allows for limited pharmacological isolation of the α1A-adrenoceptor permitting characterization of the properties of selective antagonists.
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50.
Since January 1990, data from uveitis patients have been systematically stored in a computer data bank. During the period from January 1990 to March 1993, 435 new patients (185 female and 250 male, mean age 43 years; range 6–92) were seen at the Uveitis Clinic of the Hopital Jules Gonin. These 435 patients (630 eyes) were subdivided into anterior uveitis (268 patients — 62%), intermediate uveitis (47 patients — 11%), posterior uveitis (89 patients — 20%) and panuveitis (31 patients — 7%). The incidence of uveitis for the referral area considered was calculated to be 17 per 100,000 inhabitants per year. A specifie diagnosis was found in 312 cases (72%). The most frequently diagnosed entities were HLA-B27-associated acute anterior uveitis (67 cases — 15.4%), uveitis associated with acute herpes zoster ophthalmicus (40 cases — 9.2%), toxoplasmosis (39 cases — 9%), typical pars planitis (29 cases — 6.7%), sarcoidosis (29 cases — 6.7%), Fuchs' heterochromic cyclitis (27 cases — 6.2%), herpetic anterior uveitis (21 cases — 4.8%) and acute retinal necrosis (11 cases — 2.5%). Incidence and distribution of most disease entities correspond to those of other European series.  相似文献   
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