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1.
白蛋白微球作为肝靶向给药载体的研究   总被引:16,自引:0,他引:16  
用均匀设计方法和计算机技术筛选了乳化化学交联法制备白蛋白微球的六个因素,十二个水平。优化出最佳制备工艺,制备了平均粒径0.41~0.47μm的白蛋白微球。将此工艺制备的125I-白蛋白微球做动物体内研究,结果表明微球iv后主要浓集在肝脏,可达注入总剂量的68%,此微球在靶组织肝脏的变化规律可用二室模型契合。  相似文献   
2.
Reference data files support the evaluation of myocardial perfusion single-photon emission tomography (SPET). The aim of this study was to create a large reference data base for technetium-99m sestamibi SPET, age and gender matched to the general patient population. One hundred and twenty-eight healthy volunteers (76 males and 52 females) with a likelihood of coronary artery disease of less than 5% underwent rest and maximal exercise99mTc-sestamibi SPET with a 2-day protocol and 180° elliptical rotation. The normalized activity values of99mTc-sestamibi in the inferior wall differed significantly between men and women. Age variations were found for men in the anterior wall. Normalized activity values in all four walls were strikingly similar during rest and stress. Our results suggest that the use of reference files in99mTc-sestamibi SPET requires a gender- and, for males, possibly an age-matched reference population. Different reference files at rest and during stress might not be necessary.  相似文献   
3.
Background: There is increasing recognition of surgeons' physical fatigue in the new ergonomic environment of laparoscopic surgery. The purpose of this study was to determine what the differences are in the movement of the surgeon's axial skeleton between laparoscopic and open operations. Methods: Surgeons' body positions were recorded on videotape during four laparoscopic (LAP) and six open (OP) operations. The percent of time the head and back were in a normal, bent, or twisted position as well as the number of changes in head and back position were tabulated using a computer program. A separate laboratory study was performed on four surgeons ``walking' a 0.5-inch polyethylene tubing forward and backward using laparoscopic and open techniques. The movements of the surgeons' head, trunk, and pelvis were measured using a three-camera kinematic system (Kin). The center of pressure was recorded using a floor-mounted forceplate (Fp). Results: In the operating room surgeons' head and back positions were more often straight in laparoscopic procedures and more often bent in open operations. The number of changes in back position per minute were significantly decreased when the laparoscopic-only part of surgery was analyzed. In the laboratory the subjects' head position was significantly (p= 0.02) more upright and the anteroposterior (AP) and rotational range of motion of the head was significantly reduced during laparoscopy. Subjects' CP was more anterior and there was a significant reduction in the AP range of motion of the CP during laparoscopy. Conclusions: Our study suggests that surgeons exhibit decreased mobility of the head and back and less anteroposterior weight shifting during laparoscopic manipulations despite a more upright posture. This more restricted posture during laparoscopic surgery may induce fatigue by limiting the natural changes in body posture that occur during open surgery. Received: 3 March 1996/Accepted: 2 July 1996  相似文献   
4.
Summary Based on the anatomic data obtained from earlier studies on the vascular anatomy of the hand, the vascular architecture in the palm of the hand was studied on 60 sides of unembalmed adult upper extremities. Each palm was divided into 64 squares by 8 sagittal and 8 transverse sections. The vascular architecture in these squares and the arterial relations between them were observed and measured by angiography, operative microscopic dissection and computerised three-dimensional reconstruction. According to the pattern of the blood-vessels, the amputated palms can be classified into 4 types. The anatomic basis for the vascular anastomosis in each type is defined. There are three key-areas for the blood-supply of the palm and their significance is discussed. Apart from the 4 types of transversely amputated palms, the repair programe of the blood-vessles in 4 types of common obliquely amputated palms are also discussed.
Etude complémentaire de l'anatomie vasculaire de la main pour la réimplantation des amputations transpalmaires
Résumé Sur la base de données anatomiques obtenues lors de précédents travaux sur l'anatomie vasculaire de la main, l'architecture vasculaire palmaire a été étudiée sur 60 extrémités supérieures de cadavres d'adultes, non embaumés. Chaque paume a été divisée en 64 carrés par 8 sections sagittales et 8 sections transversales. L'architecture vasculaire à l'intérieur des carrés et les relations artérielles entre eux ont été étudiées et mesurées par angiographie, dissection au microscope opérateur et reconstruction computérisée en 3D. Les paumes amputées ont été regroupées en 4 types d'après la distribution des vaisseaux sanguins. Les données anatomiques concernant les anastomoses vasculaires sont précisées. Il existe trois zones clés pour l'irrigation de la paume. Leur importance quant à l'irrigation de la main est exposée. Outre la division des paumes amputées transversalement en 4 types, le programme de réparation de vaisseaux dans les 4 types d'amputations obliques communes de la paume et aussi discuté.
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5.
A major allergen has been identified in an aqueous extract of the 'green nimitti' midge, Cladotanytarsus lewisi (Diptera: Chironomidae). Following chromatography on Sephadex G-100 allergenic activity, as assessed by skin ('prick') testing, eluted as two closely related peaks (pools I and II) at about 50% bed volume. When these pools were applied separately to columns of CM-cellulose, activity in each eluted with 0 . 05 M NaCl. Isoelectric focusing of the unfractionated allergen gave a single peak of activity at pI 4 . 3. By SDS--PAGE, biological activity in the whole 'green nimitti' extract and the material eluting from both pools I and II of the Sephadex G-100 column migrated to the same positions and were associated with a molecular size of 15,000--20,000 daltons. Skin test reactivity of the unfractionated material and the Sephadex G-100 pool I and II eluates were all destroyed following incubation with trypsin, chymotrypsin, thermolysin and neuraminidase. These experiments indicate that a major allergen derived from the 'green nimitti' midge, a cause of widespread and severe immediate-type allergy in the Sudan, is an acidic glycoprotein of 15,000--20,000 molecular weight.  相似文献   
6.
Preoperative bone scintigraphy of the femoral head in 33 hips with slipped capital femoral epiphysis, showed no relation to duration of symptoms or degree of slip. The preoperative uptake was always normal or increased. Two hips had postoperative femoral head uptake below normal, both had complications affecting the vascular supply, resulting in necrosis of the femoral head and severe arthrosis. At follow-up after 10 (5-15) years of 28 hips, no relation could be demonstrated between Adolescent Hip Questionnaire which included clinical data, and radiography or magnetic resonance imaging. We only recommend scintigraphy after complications jeopardizing the vascular supply of the femoral head in slipped capital femoral epiphysis.  相似文献   
7.
In severely burned patients the approach to the central vein is often difficult due to concomitant edema, but also due to the fact that the skin area, where commonly used approaches are performed, is burned as well, whereas the axillary region is often not involved. In order to perform an axillary approach to the central vein as an alternative to the commonly used approaches in patients, an anatomical dissection in fresh human cadavers was carried out. Considering the anatomical landmarks which were found during dissection of the axillary region, the axillary approach to the central vein was used in 35 patients in our intensive burn care unit with unaffected axillary skin. In three cases the only complication observed was an occasional puncture of the axillary artery without major hematoma. The infection rate of the catheters was similar to the commonly used puncture sites. This approach to the central venous line in severely burned patients can be recommended.  相似文献   
8.
9.
BACKGROUND AND PURPOSE: Single agent mitomycin c (MMC) has been shown to improve the outcome of radiotherapy in single institution trials. In order to confirm these findings in a broader worldwide setting, the International Atomic Energy Agency (IAEA) initiated a multicentre trial randomising between radiotherapy alone versus radiotherapy plus MMC. MATERIAL AND METHODS: Patients with advanced head and neck cancer were treated with primary curative radiotherapy (66 Gy in 33 fractions with five fractions per week) +/-a single injection (15 mg/m(2)) of MMC at the end of the first week of radiotherapy. Stratification parameters were tumour localization, T-stage, N-stage, and institution. A total of 558 patients were recruited in the trial from February 1996 to December 1999. Insufficient accrual and reporting led to the exclusion of three centres. The final study population consisted of 478 patients from seven centres. Patients had stage III (n=223) or stage IV (n=255) squamous cell carcinoma of the oral cavity (n=230), oropharynx (n=140), hypopharynx (n=65) or larynx (n=43). Prognostic factors like age, gender, site, size, differentiation and stage were well balanced between the two arms. RESULTS: The haematological side effects of MMC were very modest (<5% grade 3-4) and did not require any specific interventions. Furthermore, MMC did not enhance the incidence or severity of acute and late radiation side effects. Confluent mucositis and dry skin desquamation was common, occurring in 56% and 62% of patients, respectively. The overall 3-year primary locoregional tumour control, disease-specific and overall survival rates were 19, 36 and 30%, respectively. Gender, haemoglobin drop, tumour site, tumour and nodal stage were significant parameters for loco-regional tumour control. There was no significant effect of MMC on locoregional control or survival, except for the 161 N0 patients, where MMC resulted in a better loco-regional control (3-year estimate 16% vs. 29%, P=0.01). CONCLUSIONS: The study did not show any major influence of MMC on loco-regional tumour control, survival or morbidity after primary radiotherapy in stage III-IV head and neck cancer except in N0 patients where loco-regional control was significantly improved.  相似文献   
10.
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