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101.
BACKGROUND/PURPOSE: Bartonella henselaeis the causative agent of cat scratch disease (CSD), manifesting as fever and acute regional lymphadenopathy. Although serologic testing is the reference method for diagnosis, successful use of immunohistochemical (IHC) stain of regional lymph nodes for the diagnosis of CSD has been reported. To determine the characterization and diagnostic potential of IHC in lymphadenopathy of CSD, lymph nodes were excised from patients with suspected CSD for further evaluation. METHODS: Polyclonal antibody-based IHC studies were performed for the detection of B. henselae. Between January 2001 and December 2004, the reference laboratory of the Center for Disease Control, Taiwan, received a total of 377 sera from 352 reported suspected CSD cases. Twenty-three formalin-fixed paraffin-embedded lymph nodes from 16 patients and two skin biopsies from two patients suspected of having CSD were included in this study. Nine of them were serologically confirmed to have CSD and the others were seronegative but suspected to have CSD by the attending physicians. Seven lymph node specimens were obtained from tuberculosis patients for comparison. RESULTS: We demonstrated that the microorganisms existed in the cytoplasm of histiocytes within the granulomatous lesions in nine lymph nodes and one skin biopsy. Among the nine lymph nodes with IHC (+) stains, three were seronegative. On the other hand, three cases were IHC (+) and six cases were IHC (-) among nine seronegative patients. In addition, two seronegative patients with skin biopsy showed one IHC (+) and one IHC (-). CONCLUSION: IHC can contribute to the etiologic diagnosis of B. henselaelymphadenopathy when serology and molecular techniques are not available.  相似文献   
102.
Background: Despite the fact that obesity is a known risk factor for cardiovascular disease, many studies have failed to demonstrate that obesity is independently associated with an increased risk of cardiovascular morbidity and mortality in nondiabetic patients undergoing coronary artery bypass graft surgery. The authors investigated the influence of obesity on adverse postoperative outcomes in diabetic and nondiabetic patients after primary coronary artery bypass surgery.

Methods: A retrospective cohort study of patients undergoing primary coronary artery bypass surgery (n = 9,862) between January 1995 and December 2004 at the Texas Heart Institute was performed. Diabetic (n = 3,374) and nondiabetic patients (n = 6,488) were classified into five groups, according to their body mass index: normal weight (n = 2,148), overweight (n = 4,257), mild obesity (n = 2,298), moderate obesity (n = 785), or morbid obesity (n = 338). Multivariate, stepwise logistic regression was performed controlling for patient demographics, medical history, and preoperative medications to determine whether obesity was independently associated with an increased risk of adverse postoperative outcomes.

Results: Obesity in nondiabetic patients was not independently associated with an increased risk of adverse postoperative outcomes. In contrast, obesity in diabetic patients was independently associated with a significantly increased risk of postoperative respiratory failure (odds ratio [OR], 2.26; 95% confidence interval [CI], 1.41-3.61; P < 0.001), ventricular tachycardia (OR, 2.27; 95% CI, 1.18-4.35; P < 0.02), atrial fibrillation (OR, 1.56; 95% CI, 1.03-2.38; P < 0.04), atrial flutter (OR, 2.38; 95% CI, 1.29-4.40; P < 0.01), renal insufficiency (OR, 1.66; 95% CI, 1.10-3.41; P < 0.03), and leg wound infection (OR, 5.34; 95% CI, 2.27-12.54; P < 0.001). Obesity in diabetic patients was not independently associated with an increased risk of mortality, stroke, myocardial infarction, sepsis, or sternal wound infection.  相似文献   

103.
104.
本文简介海南岛的自然地理、啮齿动物地理区划和社会经济(包括人口数、性别年龄分布、人工植被、耕作习惯等)与钩端螺旋体病发生或流行有关的自然因素.扼要报告自1958─1991年以来各年度该病的发病率与病死率,比较了50─90年代总的发病态势是低→高→低,并略作了分析。  相似文献   
105.
106.
OBJECTIVE: To observe the morphological changes of Balb/C mouse embryonic stem cells following directed differentiation into pancreatic islet-like cell clusters (PICC) in vitro using atomic force microscope (AFM). METHODS: Balb/C mouse embryonic stem cells were first cultured into embryonic bodies (EBs) and allowed to differentiate spontaneously for 4 days. The cells were then transferred to gelatin-coated dishes for the EBs to attach and spread on the tissue culture plates, in the course of which a series of cell growth factors such as basic fibroblast growth factor (bFGF), insulin-like growth factor 1 (IGF-1) and nicotinamide were added into the culture medium at specific time points to induce directed differentiation of the stem cells into PICC. Immunocytochemistry was employed to detect the cells positive for insulin and glucagon, which were observed with AFM. RESULTS: The embryonic stem cells developed into cell clusters of different sizes, in which the cells were tightly arranged. Islet B cells were numerous in the center of clusters and darkly stained, but fewer in the peripherals with lighter stains. Islet A cells expressing glucagon were relatively fewer in the cell clusters, found mainly in the peripherals. Scanning of the insulin-positive clusters by AFM revealed large quantity of tissue fibers resembling nerve fibers that formed a reticular structure in disorderly arrangement. Numerous round granules were observed in the cytoplasm of almost identical sizes ranging from 0.5 to 1.0 mum in diameter. CONCLUSION: The cell clusters obtained by directed differentiation are mature in both morphology and function with also well organized structures.  相似文献   
107.
1972年出土的<武威汉代医简>第9、10两简有"五(疒夅)"及"石(疒夅)"、"血(疒夅)"、"膏(疒夅)"、"泔(疒夅)"的记载.就其病名与症状的描述而言,颇似当今的淋证.本文就两简中的"(疒夅)"、"泔(疒夅)"、"五(疒夅)"进行探讨,认为"(疒夅)"是多义字,有罢病、淋证等含义.同时又是"癃"的省写,故"(疒夅)"字即"癃"字,属"淋证"."泔(疒夅)",为米泔汁样小便,伴小便频数涩痛的症状,类似于当今临床"白浊"的部分表现."五(疒夅)"中的第五淋尚难以确定.  相似文献   
108.
Cardiac PET combined with CT is rapidly expanding despite artifactual defects and false-positive results due to misregistration of PET and CT attenuation correction data-the frequency, cause, and correction of which remain undetermined. METHODS: Two hundred fifty-nine consecutive patients underwent diagnostic rest-dipyridamole myocardial perfusion PET/CT using (82)Rb, a 16-slice PET/CT scanner, helical CT attenuation correction with breathing and also at end-expiratory breath-hold, and averaged cine CT data during breathing. Misregistration on superimposed PET/CT fusion images was objectively measured in millimeters and correlated with associated quantitative size and severity of PET defects. Misregistration artifacts were defined as PET defects with corresponding misregistration on helical CT-PET fusion images that resolved after correct coregistration using a repeat CT scan, cine CT averaged attenuation during normal breathing, or shifted cine CT data that coregistered with PET data. RESULTS: Misregistration of standard helical CT PET images caused artifactual PET defects in 103 of 259 (40%) patients that were moderate to severe in 59 (23%) (P = 0.0000) and quantitatively normalized on cine or shifted cine CT PET (P = 0.0000). Quantitative misregistration was a powerful predictor of artifact size and severity (P = 0.0000), particularly for transaxial misregistration >6 mm occurring in anterior or lateral areas in 76%, in inferior areas in 16%, and at the apex in 8% of 103 artifactual defects. CONCLUSION: Misregistration of helical CT attenuation and PET emission images causes artifactual defects with false-positive results in 40% of patients that normalize on cine CT PET using averaged CT attenuation data during normal breathing comparable to normal breathing during PET emission scanning and shifting cine CT images to coregister visually with PET.  相似文献   
109.
Objective To compare the clinical efficacy of postoperative intraperitoneal chemotherapy combined with systemic chemotherapy to systemic chemotherapy alone for serosa-involved colorectal cancer. Methods According to the criteria of serosa-involving in colorectal cancer, 332 cases were divided into 2 groups prospectively without randomization. Study group (n=166) was treated with intraperitoneal chemotherapy combined with systemic chemotherapy, and control group (n=166) with systemic chemotherapy alone. Incidence of local recurrence, peritoneal metastasis, hepatic metastasis, other distant metastasis and 3-year, 5-year overall survival (OS) rate of two groups were compared. Results 3-year and 5-year OS rates of stage Ⅱ B in study group were similar to those in control group (χ2=0.612,P=0.434). The above rates of stage Ⅲ in study group were higher than those in control group (χ2=3.989,P=0.046). Either the study group or the control group, the 3-year and 5-year OS rates of patients undergone laparoscopic surgery or open surgery were similar (P=0.839, P=0.172). Incidences of local recurrence, peritoneal metastasis and hepatic metastasis in study group were 1.9%, 3.8% and 3.8% respetively, lower than those in control group (8.2%,9.5% and 10.1%,P<0.05). Distant metastasis rate in study group was similar to that in control group. In study group, intraperitoneal chemotherapy regimen with Oxaliplatin had lower rates of peritoneal metastasis and hepatic metastasis as compared to that with Cisplatin (0.9% vs 8.8% ,P=0.019), while the incidences of local recurrence and other distant metastasis were similar. Conclusions Postoperative intraperitoneal chemotherapy combined with systemic chemotherapy improves 3-year and 5-year overall survival rates in patients with stage Ⅲ serosa-involved colorectal cancer, and decreases local recurrence, peritoneal metastasis and liver metastasis rate, especially when intraperitoneal chemotherapy regimen contains Oxaliphtin. Comparing with open surgery, laparoscopic surgery dose not improve 3-year and S-year overall survival rates in patients receiving combined chemotherapy or systemic chemotherapy alone.  相似文献   
110.
Amniotic fluid mesenchymal stem cells have the ability to secrete neurotrophic factors that are able to promote neuron survival in vitro. The purpose of this study was to evaluate the effects of neurotrophic factors secreted by rat amniotic fluid mesenchymal stem cells on regeneration of sciatic nerve after crush injury. Fifty Sprague-Dawley rats weighing 250-300 g were used. The left sciatic nerve was crushed with a vessel clamp. Rat amniotic fluid mesenchymal stem cells embedded in fibrin glue were delivered to the injured nerve. Enzyme-linked immunosorbent assay (ELISA) and immunocytochemistry were used to detect neurotrophic factors secreted by the amniotic fluid mesenchymal stem cells. Nerve regeneration was assessed by motor function, electrophysiology, histology, and immunocytochemistry studies. Positive CD29/44, and negative CD11b/45, as well as high levels of expression of brain-derived neurotrophic factor, glia cell line-derived neurotrophic factor, ciliary neurotrophic factor (CNTF), nerve growth factor, and neurotrophin-3 (NT-3) were demonstrated in amniotic fluid mesenchymal stem cells. Motor function recovery, the compound muscle action potential, and nerve conduction latency showed significant improvement in rats treated with amniotic fluid mesenchymal stem cells. ELISA measurement in retrieved nerves displayed statistically significant elevation of CNTF and NT-3. The immunocytochemical studies demonstrated positive staining for NT-3 and CNTF in transplanted cells. The histology and immunocytochemistry studies revealed less fibrosis and a high level of expression of S-100 and glial fibrillary acid protein at the crush site. Rat amniotic fluid mesenchymal stem cells may facilitate regeneration in the sciatic nerve after crush injury. The increased nerve regeneration found in this study may be due to the neurotrophic factors secreted by amniotic fluid mesenchymal stem cells.  相似文献   
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