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991.
992.
JW Kronson BJ Hering DE Sutherland Y Tanioka JP Leone N Kirchhof AP Dalmasso 《Canadian Metallurgical Quarterly》1998,65(12):1549-1554
BACKGROUND: Discordant islet xenografts are immediately nonfunctional in nonimmunosuppressed recipients other than the mouse, a process called primary nonfunction. Although at present it is unknown whether complement is involved, complement might participate in the induction of primary nonfunction through a number of mechanisms. We investigated the potential role of the membrane attack complex of complement in primary nonfunction of transplanted xenoislets. METHODS: Canine islets were transplanted into both nonimmunosuppressed and immunosuppressed normocomplementemic and C6-deficient (C6D) PVG rats. Cyclosporine, rapamycin, deoxyspergualin, and mycophenolate mofetil were used for immunosuppression from day -3 to cessation of islet cell function. Serum glucose was measured at 6 hr after transplant and daily thereafter. Xenograft tissue sections were obtained at various times after transplant and stained for inflammatory cells and insulin. RESULTS: Canine islets grafted in nonimmunosuppressed C6D rats and normocomplementemic rats underwent primary nonfunction in all animals. The incidence of primary nonfunction in animals receiving a four-drug immunosuppressive regimen was 33% in the normocomplementemic rats but only 10% in the C6D rats. The mean functional islet survival time was 1.57+/-0.33 days in the normocomplementemic group and 2.70+/-0.67 days in the C6D group (P=0.38). The islet xenografts showed little difference in degree and composition of cell infiltration between normocomplementemic and C6D rats. CONCLUSION: The membrane attack complex does not appear to play a major role in primary nonfunction of canine islet xenografts in nonimmunosuppressed PVG rats. However, there was a lower incidence of primary nonfunction and a longer posttransplant survival time in immunosuppressed C6D rats, suggesting the membrane attack complex may play a minor role in recipients that are heavily immunosuppressed. 相似文献
993.
Assisted reproduction techniques (ART) are modern medical methods which should help infertile couples to resolve their problems. With the introduction of ART new ethical and technical problems arise. The authors wish to demonstrate on the submitted two case-histories the need of interdisciplinary collaboration of the specialist in internal medicine and gynaecologist when dealing with a serious complication of ART--ovarian hyperstimulation syndrome (OHSS). 相似文献
994.
Z Trizna M de Andrade AP Kyritsis K Briggs VA Levin JM Bruner Q Wei ML Bondy 《Canadian Metallurgical Quarterly》1998,7(6):553-555
The simultaneous determination of betamethasone dipropionate (BD) and salicylic acid (SA) in both ointment and topical solution was developed using high-performance liquid chromatography (HPLC). The method was standardized using a LiChrospher 100 RP-18 (125 x 4 mm, 5 microns) column, acetonitrile-tetrahydrofuran-acetic acid 1% (25:20:55 v/v), apparent pH 3.3, as mobile phase, and UV detection at 254 nm. The peak area response versus concentration was linear in a concentration range from 5.0 to 50.0 micrograms/ml of BD and from 20.0 to 200.0 micrograms/ml of SA. The correlation coefficients were 0.9997 for BD and 0.9987 for SA, and the relative standard errors of estimates were 1.38% for BD and 3.27% for SA. The coefficient of variation and the recovery average were, respectively, 0.41-1.15% and 100.09% for BD, and 0.57-0.95% and 99.79% for SA. 相似文献
995.
VN Gorbunov AP Sytnik NN Korenev SA Gordeev EV Stoliarchuk GA Urzhumtseva 《Canadian Metallurgical Quarterly》1998,(9):14-17
Results of treatment of 1309 patients with perforated and bleeding pyloroduodenal ulcers for 20-years period have been analysed. Resection of the stomach performed in 85 cases resulted in high postoperative lethality which made up in bleeding ulcers 14.8%. Drainage operations of the stomach with excision or suturing of ulcer combined with bilateral truncal vagotomy was performed in 60 patients, postoperative lethality rate being 8.4%. 128 patients underwent selective proximal vagotomy together with pyloro- and duodenoplasty, lethality rate being 1.6%. Combined vagotomy (posterior truncal and anterior sero-muscular) with excision of ulcer, transversal pyloroplasty and duodenoplasty was carried out in 1036 patients (postoperative lethality--2.4%). Excellent and good functional results were achieved in 79.6% of the patients. 相似文献
996.
997.
998.
AP Waters 《Canadian Metallurgical Quarterly》1998,4(1):23-24
Toxicosis due to microcystin-containing blue-green algae has been sporadically reported in a variety of animal species. Most reports of intoxication involve algal blooms during periods of warm temperatures and abundant sunshine in the spring or early summer. A case of blue-green algae toxicosis with lesions attributable to toxins from Microcystis aeruginosa is described in 4 cattle from southern Georgia during November. The case was unusual in that characteristic hepatic necrosis was accompanied by severe mesenteric edema and peritoneal effusion. In addition, weather conditions and location were not expected to be conducive to algal blooms. Rapid diagnosis and identification of the probable source of intoxication allowed the owner to move the herd away from the affected pond. This action limited losses to only the 4 cattle. 相似文献
999.
As they mature and become sexually active, more young people face serious health risks. Most face these risks with too little factual information, too little guidance about sexual responsibility, and too little access to health care. Meeting young adults' diverse needs challenges parents, communities, health care providers, and educators. Despite urgent needs, program efforts have been slight and slowed by controversy. 相似文献
1000.
Genes encoding fibroblast growth factors (FGFs) are expressed in early Xenopus neurulae in the prospective midbrain-hindbrain boundary (MHB) region of the neural plate. These expression domains overlap those of XWnt-1 and XEn-2, raising the question of the role of FGF signalling in the regulation of these genes, and more generally about the function of FGF during Xenopus midbrain development. We report that explants from the prospective MHB grafted into the anterior neural plate in midneurula stage embryos induce XWnt-1 expression and, at a lower frequency, XEn-2 expression in the vicinity of the graft. Such a process is likely to involve FGF signalling. Implantation of FGF4- or FGF8-soaked beads in the prospective forebrain at neurula and tailbud stages causes the up-regulation of XWnt-1 and XEn-2 in the dorsal and lateral region of the anterior midbrain. This effect is not relayed by endogenous FGF genes since exogenous FGFs inhibit the expression of endogenous XFGF3 or XFGF8. However, consequences of grafting MHB or implanting FGF4 or FGF8 beads on tadpole brain development are different. MHB grafts induce ectopic mesencephalic structures, strongly suggesting that a region homologous to the isthmic organizer of amniotes is specified as early as the midneurula stage. In contrast, exogenous FGFs do not cause the formation of ectopic mesencephalic structures but an overgrowth of mesencephalon and diencephalon. We propose that FGF signals from the prospective MHB play a crucial role in the spatial regulation of XWnt-1 and XEn-2 expression in the posterior midbrain, but that the full organizing activity of the MHB involves other factors in combination with FGF. 相似文献