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941.
Lateral unicompartmental knee arthroplasty (UKA) is a valid alternative treatment in the event of arthritis confined to the lateral compartment. This paper examines its indications, technique and short to medium-term results. A total of 159 Miller–Galante cemented UKA prostheses (Zimmer, Warsaw, Indiana) were implanted consecutively (131 medial and 28 lateral) by the same surgeon. This study investigates 28 lateral UKAs in 27 patients. Twenty-five implants in 24 patients (including a subject operated bilaterally) were followed up for 12–60 months. Three patients were discarded on account of to short a follow-up period. The Hospital for Special Surgery (HSS) knee score was used to compare the pre- and post-operative results of the lateral UKA patients. The HSS score improved from a pre-op mean of 59.92 (range 48–68) to 88.04 (range 71–95) at the last follow-up. There was a positive increase in the pain, function and ROM components of the score. The lateral UKA prosthesis can be regarded as a sound alternative to total knee replacement. Correct patient selection on the basis of optimum surgical indications, however, is essential. No benefits of funds were received in support of the study.  相似文献   
942.
Introduction The authors report a case of interhemispheric ependymal cyst accompanied with agenesis of the corpus callosum in a fetus. Discussion Routine ultrasound and subsequent magnetic resonance imaging of a 20-year-old woman at 33 weeks and 1 day of gestation detected a large interhemispheric cystic lesion in the fetal cranial cavity. Caesarian section was carried out at 36 weeks because of the progressive enlargement of the fetal head. The cyst was multiloculated and a cyst peritoneal shunt placement resulted in collapse of the drained cyst components followed by enlargement of others. After wrack-a-mole-like shunt revisions, open surgery was performed at the age of 2 years. Cyst walls were fenestrated and the cavities were communicated with each other and eventually with the lateral ventricle. Pathological diagnosis of the cyst wall was ependymal cyst. The boy is now 3 years old, and growing without apparent developmental delay or recurrence. Current concept and management policy of the interhemispheric cyst accompanied with agenesis of the corpus callosum is reviewed.  相似文献   
943.
Complications in a donor are a distressing but inevitable occurrence, since graft procurement is a major undertaking. Although the technique for procurement has some similarities to hepatic resection, a donor is very unlike a patient with malignancy. The risk factors identified in these patients cannot be extrapolated to donors. Donor hepatectomy carried out from June 1995 to March 2005 in Chang Gung Memorial Hospital, Kaohsiung Medical Center was reviewed with the aim of identifying risk factors for complications. There were 204 living donor liver transplants, with 205 donor hepatectomies, as 1 living donor liver transplantation was a dual graft. Ten donors (4.88%) suffered complications. There was no difference in terms of age, gender, body weight, operation, and parenchymal time between those who had complications and those who did not. There was also no difference in liver function tests between the 2 groups of donors, but the total bilirubin was significantly higher in donors with complications. The graft weight and remnant liver volume were also similar. The proportion of donors with fatty liver was the same between the 2 groups. The mean blood loss in donors with complications was 170 +/- 79 mL, and that for donors without complications was 95 +/- 77 mL. There was a statistically significant greater blood loss in donors with complications (P < 0.05). The number of segments removed in donors with complications was also higher compared to donors without complications (P < 0.03). Using multivariate analysis, intraoperative blood loss and the number of segments removed were found to be independent risk factors for donor complications. Intraoperative blood loss during graft procurement must be kept low to minimize complications in donors.  相似文献   
944.
Several likely precursors of schizophrenia have been identified. These range from possibly causative features, such as exposure to perinatal insults, to features that are the effects of an underlying vulnerability, such as abnormal childhood behaviors. Unfortunately none of these precursors is specific enough to be used in identifying individuals for targeted preventive treatment. A more useful strategy is to combine risk factors for psychotic disorders in a population seeking help for psychiatric problems. Thus, individuals who are possibly prodromal are identified. Research into this group has found high rates of onset of psychotic disorders, particularly schizophrenia, within a short time frame. Preliminary treatment trials suggest that symptoms can be reduced and psychosis onset possibly delayed or averted.  相似文献   
945.
Magnetic susceptibility, as a physical property of materials, plays important roles in many physical, chemical, engineering, and medical applications. Its quantification becomes of significant interest when MRI becomes a commonly used technique in biomedical applications. A general method is presented here for quantifying arbitrary magnetic susceptibility distributions in a localized region on the basis of first principles of magnetic induction field distributions in space. A proof of the concept was demonstrated by computer simulations. The study establishes the methodological basis for quantitative magnetic susceptibility imaging with MR.  相似文献   
946.
Hemosuccus pancreaticus (HP) is a rare cause of gastrointestinal bleeding, usually due to rupture of a visceral artery aneurysm in chronic pancreatitis. Other causes of HP are rare. We present a case of HP which occurred in a patient with chronic calcifying pancreatitis and a pancreatic pseudocyst documented by ultrasonography and computed tomography. With detectable fresh blood in the descending duodenum, an aneurysm in the pancreatic head was revealed by superior mesenteric angiography as the suspected origin of intermittent bleeding from the pancreatic duct. Because an artery feeding the pseudocyst could not be identified, angiographic embolization was not possible. Surgical resection or ligation was difficult by laparotomy; therefore, intraoperative packing of the pseudocyst with absorbable gelatin sponges was achieved via a cannula through a directly punctured site in the pseudocyst wall. The patient has been followed for 4.25 years with no further episodes of HP. It is possible that the packing of a pancreatic pseudocyst with gelatin sponges is a method that can be used in similar cases, where control of hemostasis is the primary concern. The packing of a pancreatic pseudocyst with gelatin sponges is a technique that can be performed not only via laparotomy but also via laparoscopy or concomitant angiography and ultrasonography.  相似文献   
947.
In this review article, we demonstrate the mucin expression profile in normal tissue, invasive ductal carcinoma (IDC), two subtypes of intraductal papillary–mucinous neoplasm (IPMN dark cell type and IPMN clear cell type), pancreatic intraepithelial neoplasia (PanIN), and mucinous cystic neoplasm (MCN) of the pancreas. In MUC1, there are various glycoforms, such as poorly glycosylated MUC1, sialylated MUC1, and fully glycosylated MUC1. IDCs showed high expression of all the glycoforms of MUC1. IPMNs dark cell type showed no expression or low expression of all the glycoforms of MUC1. IPMNs clear cell type showed low expression of poorly glycosylated MUC1, but expression of sialylated MUC1 and fully glycosylated MUC1. Expression of MUC2 was negative in IDCs, high in IPMNs dark cell type and low in IPMNs clear cell type. MUC5AC was highly expressed in IDCs, IPMNs dark cell type, and IPMNs clear cell type. MUC6 expression was higher in IPMNs clear cell type than in IDCs and IPMNs dark cell type. Our recent study demonstrated that high expression of MUC4 in IDCs is correlated with a poor outcome for patients. In PanINs, expression of both MUC5AC and MUC6 are an early event, whereas up-regulation of MUC1 is a late event. MCNs do not look as if they will show a specific mucin expression profile according to the literature review.  相似文献   
948.
BACKGROUND AND PURPOSE: The potential risk of prolongation of treatment time in cervical cancer has been reported for many low-dose rate (LDR) studies, with an estimated loss of local control ranging from 0.3 to 1.6% per day of treatment prolongation. Since the treatment schedule for fractionated high-dose rate intracavitary brachytherapy (HDRICB) is not directly comparable with that for low-dose rate studies, this report aims to evaluate the adverse effect of treatment prolongation specifically for cervical cancer treated with HDRICB. MATERIAL AND METHODS: From September 1992 to December 1997, 257 patients diagnosed with uterine cervical cancer (35 Ib, 26 IIa, 122 IIb, 10 IIIa, 57 IIIb, 7 IVa), who underwent external radiotherapy combined with between two and four courses of HDRICB and a minimum of 3 years of follow-up (median 57 months), were analyzed. Treatment consisted of irradiation of the whole pelvis with 44-45 Gy consisting of 22-25 fractions by 5 weeks, with the dose boosted to 54-58 Gy (with central shielding) for patients diagnosed as FIGO stage IIb-IVa bilateral parametrial disease. HDRICB was performed using an Ir-192 remote afterloading technique at 1-week intervals. The standard prescribed dose for each course of HDRICB was 7.2 Gy to point A for three insertions (before July 1995), or 6.0 Gy to point A for four insertions (after July 1995). Total prescribed point A doses (external beam radiotherapy+HDRICB) ranged from 58 to 71.6 Gy (median, 65.6 Gy) for stage IB-IIA, while analogous dosage for larger lesions (stage IIb-IVa) ranged from 59 to 75.6 Gy (median, 65.6 Gy). Kaplan-Meier and multivariate analyses were used to test the effect of treatment time on pelvic control rate (PCR) and cause-specific survival (CSS) at 5 years. RESULTS: Median treatment time was 63 days. For all stages of disease, the 5-year CSS and PCR were significantly different comparing treatment times of less than and greater than or equal to 63 days [83% and 65% (P=0.004], 93% and 83% (P=0.02), respectively]. These associations were also significant for stage Ib/IIa [97% and 79% (P=0.01), and 100% and 87% (P=0.02), respectively), but not for stage IIb [75% and 72% (P=0.79), and 93% and 87% (P=0.83), respectively] or stage III [66% and 49% (P=0.2), and 83% and 72% (P=0.21), respectively]. Multivariate analysis identified three prognostic factors for CSS, stage (P<0.001), tumor response to external RT (P=0.001), and overall treatment time (OTT; P=0.006). Prognostic factors for pelvic failure were stage (P<0.001), tumor response to external RT (P=0.001), and OTT (P=0.03). Prolongation of treatment time resulted in a daily decrease in pelvic control rate of 0.67% overall, and 0.43% for stage Ib-IIa, 0.57% for stage IIb, and 0.73% for stage III patients. CONCLUSION: Analysis of the data from the current study demonstrates that the adverse effect of treatment prolongation was observed later in the treatment course for the high-dose rate (HDR) series compared to the LDR analog, however, treatment-time prolongation still negatively influenced the cause-specific survival and pelvic control rate for both dosage groups.  相似文献   
949.
慢传输型便秘模型的建立及其机制探讨   总被引:13,自引:0,他引:13  
目的 :建立实验型慢传输型便秘模型。 方法 :实验组小鼠皮下注射吗啡建立慢传输型便秘模型 ,记录小鼠粪便重量 ,利用炭沫推进试验比较实验组与对照组小鼠结肠传输功能 ;利用免疫组化技术比较两组小鼠结肠组织中Cajal细胞数量。 结果 :实验组小鼠粪便重量减轻 (P <0 .0 1) ,结肠推进率较对照组明显延长 (P <0 .0 1) ,Ca jal细胞数量较对照组明显减少 (P <0 .0 1)。 结论 :吗啡皮下注射诱导小鼠结肠慢传输型便秘模型符合疾病的基本特点 ,其发病机制可能与内源性阿片肽增多和 (或 )肠道Cajal细胞异常改变有关  相似文献   
950.
Genital herpes simplex virus (HSV) infection has substantial economic and quality-of-life consequences; not least is the risk of transmission to the fetus/infant during parturition with the subsequent effects on the family, society as a whole and healthcare providers. While general screening programs for HSV infection are not cost effective, screening of susceptible subgroups may be acceptable in some circumstances (e.g. immunocompromised patients, presumed discordant heterosexual couples, pregnant women) despite the high costs involved. First-line options for treatment and suppression of genital herpes in Europe and the US include valaciclovir, aciclovir and famciclovir. The established efficacy of valaciclovir, along with its potential for once-daily administration in many patients (versus administration up to five times daily for aciclovir), its positive effect on quality of life, its suppressive efficacy in late pregnancy and its proven reduction of viral transmission between heterosexual discordant partners support the drug’s position as a first-line therapy and suppression option in patients with genital herpes. However, the high acquisition costs compared with aciclovir will affect formulary decisions in some patients, and the favored niche for this drug, at least until evidence of prevention of transmission is demonstrated for other antivirale, would seem to be in the prevention of transmission in susceptible subgroups such as couples discordant for HSV infection (especially male-positive/female-negative couples who are planning a pregnancy), and the treatment and suppression of genital herpes in patients particularly receptive to once-daily administration.Potential disease management programs for genital herpes would thus need to balance the high costs of HSV screening and the relatively high acquisition costs of valaciclovir against the convenience of once-daily administration, the improved quality of life and the proven potential for reduced viral transmission to susceptible partners (with potential for downstream reductions in the overall socioeconomic burden of the disease) associated with oral valaciclovir.  相似文献   
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