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1.
Outflow of aqueous humor following cyclodialysis or ciliochoroidal detachment in rabbit 总被引:1,自引:0,他引:1
Cyclodialysis and ciliochoroidal detachment were performed in three eyes of three rabbits and in three eyes of another three rabbits, respectively. After aspiration of the aqueous humor, 0.1 ml of 10% sodium fluorescein was injected intracamerally, and the eyeball was enucleated between 30 minutes and one hour after injection and prepared for fluorescence microscopy. Sodium fluorescein concentrations in the supraciliary space were much greater in the group with cyclodialysis or ciliochoroidal detachment than in the normal control group. These results suggest that (1) in the eye with cyclodialysis, the aqueous humor may freely gain access to the supraciliary space through the cleft between the anterior chamber and the supraciliary space and then be removed rapidly and (2) in the eye with ciliochoroidal detachment, the aqueous humor may pass through the uveoscleral outflow pathway. 相似文献
2.
Milena Soares Santos Guilherme de Sousa Ribeiro Tainara Queiroz Oliveira Renan Cardoso Nery Santos Edilane Gouveia Kátia Salgado Daniele Takahashi Cleuber Fontes Leila Carvalho Campos Mitermayer Galvão Reis Albert Icksang Ko Joice Neves Reis 《International journal of infectious diseases》2009,13(4):456-461
3.
Teng-Yi Huang Hsiao-Wen Chung Fu-Nien Wang Cheng-Wen Ko Cheng-Yu Chen 《Magnetic resonance in medicine》2004,51(2):243-247
In this work the feasibility of separating fat and water signals using the balanced steady-state free precession (SSFP) technique is demonstrated. The technique is based on the observation (Scheffler and Hennig, Magnetic Resonance in Medicine 2003;49:395-397) that at the nominal values of TE = TR/2 in SSFP imaging, phase coherence can be achieved at essentially only two orientations (0 degrees and 180 degrees ) relative to the RF pulses in the rotating frame, under the assumption of TR < T2, and independently of the SSFP angle. This property allows in-phase and out-of-phase SSFP images to be obtained by proper choices of the center frequency offset, and thus allows the Dixon subtraction method to be utilized for effective fat-water separation. The TR and frequency offset for optimal fat-water separation are derived from theories. Experimental results from healthy subjects, using a 3.0 Tesla system, show that nearly complete fat suppression can be accomplished. 相似文献
4.
Wing‐Hong Li Moon‐Tong Cheung Candace N.S. Ho Ting‐Pong Fung Kai‐Ming Ko Kelvin K.W. Yau 《Surgical Practice》2007,11(4):138-143
Aim: To examine the survival benefit of liver and lung resection for colorectal metastasis and the potential prognostic factors that affect patient survival. Methods: All patients who had resection of lung or liver metastasis for colorectal metastasis in Queen Elizabeth Hospital, Hong Kong from 1995 to 2004 were retrospectively reviewed. The overall and disease‐free survival was analysed, in particularly between liver and lung metastasis. All factors that may have affected the survival were entered into Cox's proportional hazards regression model to identify significant variables associated with survival. Results: At 5 years, the overall survival of patients who had resection of lung and liver metastasis was 44% and 38%, respectively; the disease‐free survival was 26% and 24%, respectively. Overall and disease‐free survival of patients with resection of lung metastasis was comparable to those with resection of liver metastasis. The differentiations of primary tumour and time to metastasis were shown to be significant prognostic factors influencing overall survival. Those patients with systemic chemotherapy after resection of colorectal metastasis demonstrated a significantly higher probability of overall survival. Conclusion: Resection of lung and liver metastases from colorectal origin was safe and both procedures improved survival. The use of chemotherapy after resection of metastasis significantly improved the overall survival. 相似文献
5.
The determination of a unicellular or a multicellular origin of a tumor is an important due for understanding its etiology. To investigate this issue, we performed clonality assay of cervix cancer using polymerase chain reaction based on highly polymorphic locus of the androgen receptor gene, in which methylation of DNA correlates with inactivation of X chromosome. DNA samples were obtained from formalin-fixed, paraffin-embedded tissue of 20 invasive epidermoid carcinomas and 10 carcinoma in situ. Seven of ten carcinoma in situ, heterozygous for the androgen receptor locus, were monoclonal pattern. Among twenty invasive epidermoid carcinomas, eighteen of which showed heterozygous, twelve were monoclonal pattern and six were polyclonal pattern. We conclude that carcinoma in situ arises from a single cell. In invasive epidermoid carcinoma, most cases were monoclonal, although some cases were polyclonal. These suggest that invasive carcinoma of the cervix does not always arise from a single cell, but may arise from several cells with different mechanisms. 相似文献
6.
Jim-Shoung Lai T.-N. Wu Saou-Hsing Liou Chen-Yang Shen Chiam-Fang Guu Kquei-Nu Ko Chi. Hsueh-Yun P.-Y. Chang 《International archives of occupational and environmental health》1997,69(4):295-300
Objective: To examine the relationship between ambient lead levels and blood lead levels and to explore the modifiers of the relationship
between ambient lead and blood lead. Method: A cross-sectional study was conducted in two lead battery factories. Blood lead level and ambient lead concentration were
measured for each participant concurrently. A structured questionnaire was administered to collect sociodemographic characteristics
and occupational history. Design: Biological and personal environmental measurements of 219 lead-exposed workers were analyzed by both simple and multiple linear
regression. A regression model was selected for interpretation. Results: A high correlation (r=0.62) between ambient lead (PbA) and blood lead (PbB) was observed. In addition, numerous factors, including age, sex, alcohol
consumption, personal hygiene practice and type of lead exposure, were also found to influence blood lead levels. Although
PbB was highly correlated with PbA, blood lead level may not be effectively lowered by reducing ambient lead level. Based
on the regression coefficients, improvement of hygienic practice was more effective at lowering PbB than reducing ambient
lead level. Good hygienic practice may be the preferential way to reduce lead exposure in current conditions. Conclusion: Education of correct work practice may be more important than engineering control in the developing countries to lower blood
lead levels in lead battery factories.
Received: 28 May 1996/Accepted: 30 August 1996 相似文献
7.
Total respiratory resistance (Rrs) was measured by the application of a sine wave of airflow to the mouth at an oscillation frequency of 10 Hz. The instrument used was the Siemens Siregnost FD5. The Rrs data were correlated with height, age, sex, and weight in 73 patients and 29 healthy subjects. The patients took part in a rehabilitation program for restoration of their locomotion function. Both groups had normal lung function (VC, FEV1) and no signs of pulmonary disease. The only important determining factor for the value of the Rrs was height. The mean Rrs of 102 subjects was 0.29 +/- 0.08 kPa.1-1.s. Other studies gave values between 0.23 +/- 0.05 and 0.32 +/- 0.10 kPa.1-1.s. 相似文献
8.
9.
J C Shih T L Ko M C Lin M K Shyu C N Lee F J Hsieh 《Ultrasound in obstetrics & gynecology》2004,24(2):202-206
The relationship of large and vascularized chorioangiomas to adverse pregnancy outcome is well recognized. We present a patient with a large placental tumor and signs of impending fetal cardiac failure. The angioarchitecture of the tumor depicted by three-dimensional (3D) power Doppler ultrasound enabled us to accurately diagnose a placental chorioangioma. During the follow-up period, quantitative flow data obtained using 3D power Doppler indicated altered hemodynamics in the tumor and concomitant improvement in the condition of the fetus, enabling us to manage the mother conservatively. Spontaneous delivery occurred at 38 weeks without any complications. This report demonstrates the potential value of 3D power Doppler in prenatal diagnosis and monitoring of pregnancies complicated by large, vascularized chorioangioma. 相似文献
10.
AIM: Benign childhood epilepsy with centro-temporal spikes (BCECTS) is the most common idiopathic partial epilepsy in children. Treatment attitudes remain a controversial issue. We examine features that could suggest refractoriness at onset. METHODS: We retrospectively reviewed the medical records of 144 children with BCECTS diagnosed at the Division of Pediatric Neurology, Asan Medical Center, from March 1, 1995, to April 30, 2002 and treated with AEDs. The patients were subdivided into two groups according to the number of antiepileptic drugs used for effective seizure control. RESULTS: Of the 144 patients, 75 were male and 69 were female, with a mean age at seizure-onset of 7.2 +/- 2.3 years (range, 2.1-14.3 years); 119 children were taking one antiepileptic drug (AED) (Group A), and 25 were taking more than one (Group B). There were no significant group differences in female-to-male ratio, prescribed AEDs, number of seizures before the start of treatment, interval between seizure-onset and start of treatment, presence of secondarily generalized seizures, or presence of bilateral EEG abnormalities. The groups differed however, in mean age at seizure onset (7.6 +/- 2.2 years versus 5.1 +/- 1.9 years, p < 0.05) and percentage of patients with seizure-onset before 3 years (p < 0.05). CONCLUSIONS: When treated with AEDs, children with BCECTS usually respond well. However, an earlier onset of seizures is associated with more frequent seizures and initial refractoriness to medical treatment. 相似文献