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101.
玻璃体切除术治疗外伤性眼内炎62例   总被引:3,自引:1,他引:2  
王金兰  蒋宏苏  惠延年 《医学争鸣》2000,21(2):S018-S018
0 引言 外伤性眼内炎是眼外伤的常见并发症 ,对视力及眼球威协极大 .由于病原体随致伤物直接进入眼内 ,在眼内和玻璃体繁殖 ,产生剧烈炎症反应 ,对眼内组织造成严重破坏 .如不及时而有效的控制 ,终使视力丧失 ,眼球萎缩 .近年随着现代玻璃体手术的发展 ,外伤性眼内炎的治愈率明显提高 .现将我科收治的 6 2例报告如下 .1 对象和方法1 .1 对象 1 996 - 0 6 / 1 998- 0 6我院连续收治 6 2例外伤性眼内炎 ,其中男 5 0例 ,女 1 2例 ,年龄 2~ 45岁 ,平均 1 6 .5岁 .1 4岁以下儿童 38例 ,占 6 1 .3% .以致伤原因分类 :角膜穿通伤30例 ,巩膜穿…  相似文献   
102.
We examined the effects of the neuropeptide hormones vasopressin and oxytocin, and their respective synthetic derivatives desmopressin and isotocin, on F3II mouse mammary carcinoma cells. Vasopressin and desmopressin at concentrations ranging from 0.1 to 1 mu M were mitogenic for F3II cells and induced protein accumulation. On the contrary, oxytocin and isotocin were moderately growth inhibitory at similar doses. In confluent monolayers vasopressin stimulated the secretion of urokinase, a profibrinolytic enzyme involved in hematogenous metastasis. However, the net effect of the peptide on tumor-derived proteolytic activity was dependent on cell density. Stimulation of cell growth and urokinase production by vasopressin was strongly linked with calcium mobilization. These data suggest that vasopressin and its synthetic analog desmopressin may be important modulators of the behavior of metastatic mammary tumor cells.  相似文献   
103.
A young boy presented with an uncommon finding of impaction of upper right central incisor and transposition of canine and lateral incisor on the same side. Esthetic management of his cosmetic problem which included fixed appliance therapy followed by light cure restorations is discussed.KEY WORDS: Impaction, Transposition  相似文献   
104.
105.
3'-Azido-2',3'-dideoxythymidine (AZT), the thymidine analogue used against human immunodeficiency virus 1 (HIV-1), exhibits bone marrow and blood toxicity in humans, presumably as the result of genotoxic mechanisms induced by incorporation of AZT into eukaryotic DNA. Preferential incorporation of AZT into telomeric regions of DNA of Chinese hamster ovary (CHO) cells has been previously demonstrated by immunofluorescence using anti-AZT antibodies. We quantitatively compared the amount of [H-3]-AZT bound to telomeric and non-telomeric sequences of CHO cell DNA. DNA from cells exposed to [H-3]-AZT was digested by a mixture of restriction enzymes, frequent cutters in the overall genome, without restriction sites in the telomeric repeat. As a result, the telomeric fraction (TF): isolated by separation columns, comprised longer sequences (> 2 kb) than the non-telomeric fraction (NTF). Radioactivity associated with each fraction revealed a three fold increase in [H-3]-AZT incorporated in the TF compared with the NTF. No preferential telomeric binding was detected for [H-3]-thymidine (Tdr) or [H-3]-5'bromodeoxyuridine (BrdU) in similar experiments or in DNA of AZT-treated mouse primary fibroblasts, cells with large telomeric repeats that lack telomerase. When the chromosomal ends of high molecular weight [H-3]-AZT-DNA were digested with Pal 31, the radioactivity was double in the TF compared with the NTF. Therefore incorporation of AZT in CHO immortalized cells but not in primary fibroblasts (that lack telomerase) indirectly shows that AZT incorporation could be telomerase-mediated.  相似文献   
106.
Macrophage Fcgamma receptors have an important role in host defense and the pathophysiology of immune mediated disorders. Alteration of splenic macrophage Fcgamma receptors expression predisposes to severe infection. Inhibition or blockade of splenic macrophage Fcgamma receptors is one of the mechanisms by which immune cytopenias improve. Dopaminergic drugs have clinically significant regulatory functions on the immune response. Using an experimental model in the guinea pig we assessed the effect of commonly used dopaminergic drugs on the expression of macrophage Fcgamma receptors. Three dopa-antagonists, bromocryptine, leuprolide, and pergolide, and seven dopa-antagonists, chlorpromazine, SCH 23390, metochlopramide, sulpiride, veralipride, alizapride, and cisapride, were studied. Following guinea pig treatment with dopaminergic drugs, the clearance of IgG-sensitized RBCs in vivo, the in vitro binding of IgG-sensitized RBCs by isolated splenic macrophages and flow cytometry with monoclonal antibodies were performed. Treatment with dopa-agonists enhanced the clearance of IgG-sensitized RBCs, the in vitro binding of IgG-sensitized RBCs by isolated splenic macrophages, and the cell surface expression of both macrophage Fcgamma receptors, and vice versa, dopa-antagonists impaired macrophage Fcgamma receptors expression. Macrophage FcgammaR1,2 was more sensitive than FcgammaR2 to such dopaminergic effect. These alterations of macrophage Fcgamma receptors expression are mediated by both D1 and D2 dopamine receptors, with a major participation of D2 receptors. Dopaminergic drugs alter the clearance of IgG-coated cells by an effect at the expression of splenic macrophage Fcgamma receptors.  相似文献   
107.
为探讨体外循环(CPB)导致心脏植物神经系统(CAS)损伤的机理,了解温血心停跳液能否防止CPB后心率变异性(HRV)的降低,采用对照方法观察了温血心停跳液与冷晶体心停跳液对狗HRV的影响。结果显示:CPB后温血心停跳液组(WB组)和冷晶体心停跳液组(CC组)的全频谱(TP)、低频(LF)和高频(HF)均较术前明显降低(P<0.05),而且CC组比WB组降低更明显(P<0.05),但LF/HF在组内及组间均无明显变化(P>0.05)。CPB后24小时平均心率(MHR)明显增加(P<0.05),且CC组高于WB组(P<0.05)。本研究表明:采用温血心停跳液或冷晶体心停跳液的CPB不会干扰CAS平衡,但均能使HRV降低,温血心停跳液不能防止HRV损害。  相似文献   
108.
BACKGROUND: Angiographic embolization is an effective technique to control bleeding after blunt trauma to the liver or pelvis. Its role in penetrating trauma to the abdomen has not been studied. METHODS: From January 1992 to May 1998, 40 patients underwent angiography for bleeding resulting from intra-abdominal penetrating injuries (33 gunshot wounds, 7 stab wounds). Angiographic embolization of intraperitoneal or retroperitoneal vessels was performed by standard angiographic techniques with gelatin sponge and/or coils. Data were extracted from medical records, radiology data bank, trauma registry, and morbidity/mortality records, and compared by Student's t test and chi-square test. The main outcome measures were failure of angiographic embolization to control bleeding and complications of angiographic embolization. RESULTS: Angiography was performed during a course of nonoperative management in 6 patients (group A), because of failure to control bleeding surgically in 23 (group B), and because of late vascular complications after an initially successful operation in 11 more (group C). In 32 patients, angiography revealed active bleeding; 29 (91 %) underwent successful angiographic embolization. Of the remaining 3 patients, 2 were successfully managed surgically (1 each from groups A and B) and 1 died despite multiple surgical maneuvers (group B). One patient who developed postoperatively a large, bleeding superior mesenteric artery pseudoaneurysm, suffered extensive bowel necrosis after angiographic embolization. No other significant complication was related to angiographic embolization. CONCLUSIONS: Angiographic embolization after penetrating injuries to the abdomen is safe and effective for a small number of selected patients. It is a valuable tool for bleeding control when surgery has failed. It may be ideal for control of late vascular complications when reoperation is not desirable. It may prove to be a useful adjunct in the nonoperative treatment of selected injuries.  相似文献   
109.
The circadian timekeeping system exhibits many functional changes with aging, including a loss of sensitivity to time cues such as systemic injections of the serotonergic agonist, 8-hydroxy-2-(di-n-propylamino)tetralin (8-OH-DPAT). In order to elucidate the neurochemical mechanisms responsible for this age-related loss of sensitivity of the circadian pacemaker to serotonin agonists, the present study used quantitative autoradiography to determine whether aging decreases serotonin receptor populations in male Syrian hamsters. Four neuroanatomical regions that regulate circadian timekeeping were studied (the suprachiasmatic nuclei [SCN], the lateral geniculate nuclei [LGN], and the median raphe nucleus [MRN] and dorsal raphe nucleus [DRN]). The specific binding of [3H]8-OH-DPAT to serotonin7 (5-HT7) and serotonin1A (5-HT1A) receptors was investigated by competitive inhibition with ritanserin and pindolol, respectively. The results showed that the SCN, IGL, MRN, and DRN of the male Syrian hamster exhibited specific binding of [3H]8-OH-DPAT to both the 5-HT7 and 5-HT1A receptors, and that the latter receptor subtype is more abundant in all of these regions. At 17-19 months of age, a 50% decrease in 5-HT7 receptors was found in the DRN but not in any other regions. No significant age-related changes in 5-HT1A receptors were observed in any regions examined. The finding that a marked decrease in 5-HT7 receptors occurs in the DRN at the age previously characterized by loss of sensitivity to 8-OH-DPAT suggests that this region and this receptor subtype play important roles in 8-OH-DPAT induction of circadian phase shifts in vivo and that they constitute an important locus of aging in the circadian timing system.  相似文献   
110.
Women in the United States, particularly African-Americans and Hispanics, are at increased risk for HIV. The female condom now offers women a potentially important option for HIV prevention, yet few efforts have been made to increase its use. To elucidate strategies to promote the use of the female condom, we conducted in-depth interviews with 62 women recruited from the four major racial/ethnic groups of the U.S. (African-American, Asian-American, Hispanic, and white). Subject recruitment took place at a family planning clinic in San Francisco during 1996-97. We identified four major types of facilitators and barriers to use of the female condom: mechanical, psychosexual, interpersonal, and situational. Specifically, the mechanical facilitators and barriers included positive and negative aspects of the device, and difficulty with insertion. The psychosexual factors were female empowerment, more options for contraception and disease prevention, discomfort with vaginal insertion, and condom use norms. The interpersonal factors included: enhanced communication, relationship status, partner preferences, and partner objections. Finally, the situations that made women disinclined to use the device were: no access to the female condom when having sex and using other forms of contraceptives. The implications of these findings for HIV prevention and future research are discussed.  相似文献   
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