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281.
Summary Split or full thickness eyelid defects resulting from tumor destruction or surgical excision present a dilemma for plastic and reconstructive surgeons. Full thickness eyelid replacement requires composite grafting of the skin, together with tarsal support of its substitute and mucosa. The flap described by Fricke in 1829 was used for reconstruction of anterior lamella in six lower eyelid defects. In three of our cases chondromucosal grafts taken from nasal septum were utilized for posterior lamella repair. The results have been satisfactory from a functional and cosmetic standpoint.  相似文献   
282.
The effects of hemorrhagic shock (HE) on duodenal pH, acid-neutralizing capacity and mucosal tolerance to acid were investigated in anesthetized rats, and they were compared with those of indomethacin. HE was performed by bleeding from the carotid artery to reduce arterial blood pressure to about 55 mmHg (3 ml of bleeding per 200 g of body weight), and indomethacin was given s.c. in a dose of 5 mg/kg. Duodenal pH was determined in the outflow from the proximal duodenum (1.7 cm) which was perfused with 10(-4) M HCl, and acid-neutralizing capacity was measured by back-titration of the perfusate to pH 4.0 with 10 mM HCl. Under these conditions, duodenal pH was kept at around 6.0 as the result of neutralization in the loop (approximately 8 microEq/hr). Both HE and indomethacin significantly decreased the pH and acid-neutralizing capacity. Administration of 16,16-dimethyl prostaglandin E2 (16-dmPGE2: 30 micrograms/kg, s.c.) significantly increased both pH and acid-neutralizing capacity in normal and indomethacin-treated rats, but failed to affect these parameters in rats under HE conditions. When the duodenal loop was perfused with 50 mM HCl for 1.5 hr, both HE and indomethacin induced extensive damage in the mucosa. Pretreatment with 16-dmPGE2 significantly reduced the formation of duodenal lesions induced by indomethacin but not by HE. These results suggest that HE as well as indomethacin impaired duodenal acid-neutralizing capacity to reduce the tolerance to acid of the mucosa. The deleterious effects of HE on the mucosa may be mainly due to a decreased mucosal blood flow, but not due to a deficiency of endogenous prostaglandins.  相似文献   
283.
284.
A new classification of forms of progressive systemic scleroderma (PSS) is presented. Compared with previous classifications, it includes not only frequent, typical forms of PSS, but also rarer manifestations. For the first time, it considers pathogenetic factors, such as the phenomena which have become known concerning the immunological system, and distinguishes between noninflammatory and inflammatory subtypes. Etiological (in this case, immunogenetic) criteria are also considered. This classification is open to further differentiation and development.  相似文献   
285.
286.
Abstract A high frequency of serum complement component C4A deficiency may explain the higher prevalence and greater severity of systemic lupus erythematosus reported in Australian Aborigines. Inherited deficiencies of serum complement components C4A, C4B, and C2 were examined in two Australian Aboriginal populations from Darwin and Alice Springs and compared with the prevalence of complement deficiencies in white Australian blood donors. The frequency of C4A deficiency alleles was 29% in Darwin Aborigines compared with 12% in Alice Springs and 17% in Canberra blood donors. Partial C4B deficiency was also higher in Darwin Aborigines than in the other populations. Inherited deficiency of serum complement component C2 was not observed.  相似文献   
287.
Ten knees with early tissue breakdown after knee arthroplasty resulting in exposed prostheses were treated with different plastic surgical techniques. Six knees were successfully covered: four using a gastrocnemius musculocutaneous flap, one using a fasciocutaneous flap, and one using split-skin grafts. Four knees failed: two using local skin flaps and two using split-skin grafts. A gastrocnemius musculocutaneous flap seems to provide a reliable coverage of the exposed knee joint.  相似文献   
288.
Authors with wide experience report that the Shouldice technique for repair of inguinal hernia is very effective. The technique has not gained widespread acceptance or notoriety. For example, the 13th edition of Textbook of Surgery, edited by Sabiston, devotes only one paragraph to this type of herniorrhaphy. Because of the excellent results reported by the Shouldice Clinic, this technique was adopted at the Augusta Veterans Administration Hospital, a teaching hospital of the Medical College of Georgia. Since 1976, a total of 604 Shouldice repairs have been performed by supervised house staff; 468 patients have been followed for up to 8 years and a recurrence rate of 1.3 per cent is reported. Although the follow-up is brief, the Shouldice hernia repair is widely applicable and good results are not dependent on wide experience alone.  相似文献   
289.
The oncocytic Schneiderian papilloma (OSP) is a rare neoplasm of the nose and paranasal sinuses. The majority of the approximately twenty patients reported in the literature with this papilloma have been over the age of fifty at the time of diagnosis. The 33-year-old woman reported here is the youngest patient with this lesion to date. The OSP should be considered in the work-up of all unilateral nasal polypoid lesions. This lesion's propensity for recurrence and its documented association with synchronous malignant disease warrant surgical excision by en bloc resection of the lateral nasal wall, with corresponding careful microscopic evaluation of all excised tissue.  相似文献   
290.
The antitumor effects of two polyamine antimetabolites, alpha-difluoromethylornithine (DFMO) and methylglyoxal-bis-guanylhydrazone (MGBG), when combined with cis-diamminedichlroplatinum (CDDP) or mitomycin C (MMC), were studied using human gastric cancer cells xenotransplanted into nude mice. DFMO 1000 mg/kg and MGBG 50 mg/kg were given intraperitoneally for 6 successive days, while CDDP 3 mg/kg or MMC 2 mg/kg was given every second day. Although DFMO and MGBG plus MMC did suppress the tumor growth, the combination with CDDP led to no suppression, and rapid growth occurred after the cessation of therapy. The inhibition of tumoral DNA biosynthesis and a decline in polyamine levels, were also not observed. The polyamine antimetabolites when used with CDDP did not produce the desired antitumor efficacy, even though the platinum concentration in the tumor tissue was high. On the contrary, however, DFMO and MGBG when combined with MMC did suppress tumor growth, inhibited DNA biosynthesis, and tissue polyamine levels were low. These results suggest that though CDDP and MMC belong to a similar category of DNA attacking, bifunctional alkylating agents, the findings of these two drugs are contradictory. Here, the mechanism of action no doubt plays a contributory role.  相似文献   
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