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81.
Summary Persistent fifth aortic arch manifested as a double-lumen aortic arch (DLAA) is a rare anomaly. We present such a case with transposition of the great arteries, ventricular septal defect (VSD), and pulmonary atresia. Review of the eight previously published cases indicates relatively frequent association of DLAA with preductal coarctation of the aorta. We attempt to explain the coexistence of this lesion with DLAA. We also discuss evidence supporting derivation of the inferior channel of the DLAA from the embryologic fifth aortic arch.  相似文献   
82.
Complications during cataract surgery such as dropped nucleus or lens fragment dislocation into the vitreous cavity may become sight threatening. The recommendations regarding possible therapeutic approaches are inconsistent. Several factors like uveitis and/or an increased intraocular pressure play a major role in the decision on the further surgical procedure. Recent publications recommend an early pars plana approach in order to avoid any traction at the peripheral retina during manipulations via a limbal approach.  相似文献   
83.
Levels of prostaglandin (PG) A/B, E and F equivalents have been determined in amniotic fluid, maternal venous blood and cord blood in the course of normal deliveries at term using radioimmunoassay after proper extraction and group separation of PG's by chromatography. With progress of cervical dilatation amniotic fluid levels increased from initial values of 0.34 to 0.52 ng/ml for PG A/B up to pressing period, while PG E rised from 2.3 to 5.5 ng/ml and PG F from 4.9 to 60.4 ng/ml, respectively. Comparatively lower increases of maternal plasma levels, essentially unchanged within the last trimester, were observed from 133, 100 and 102 pg/ml for PG A/B, E and F at the early first stage of labour to levels of 231, 209 and 357 pg/ml after the second stage. Higher levels of PG's in cord blood after spontaneous deliveries, not exhibiting significant arterio-venous differences, further strengthen the limited value of PG determinations in maternal plasma for the elucidation of the role of PG's in the physiology of gestation and parturition, but support a prevailing uterine not fetal localisation of PG production. The excessive PG F increase during birth, obviously caused by selective stimulation of PG F-synthesis, validitates the hypothesis, that this PG seems to be causally responsible for initiation and maintenance of uterine contractions in normal delivery.  相似文献   
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86.

Background

Previous studies have shown a significant increase in tear protein peaks in the tears of diabetic patients suffering from dry eye. The aim of this study was to analyze the tear protein patterns from patients with diabetes mellitus who do not suffer from ocular surface diseases (DIA).

Methods

A total of 515 patients were examined in this study (255 healthy subjects (controls) and 260 patients suffering from diabetes mellitus). Tear proteins were separated by sodium-dodecyl-sulfate polyacrylamide gel electrophoresis. After digital image analysis densitometric data files were created and subsequently used for multivariate statistical procedures.

Results

A significant increase in the number of peaks was detected in diabetic patients compared to controls (P < 0.0003). The analysis of discriminance revealed a highly significant discrimination between diabetic patients and controls (Wilks lambda: 0.27; P < 0.000001). Furthermore, a significant difference in the protein pattern of diabetic patients could be detected between those suffering from dry eye or not (P < 0.002). The changes in protein patterns of diabetic patients increased with the duration of the diabetic disease. In diabetic patients with a disease duration longer than 10 years the changes were significantly more expressed than in patients with a shorter diabetic history (P < 0.003) and in healthy subjects (P < 0.0001).

Conclusions

The tear protein patterns of diabetic patients are very different in the number and intensity of spots from those of healthy subjects. Furthermore, it could be demonstrated that the differences found in the tear patterns of diabetic patients are not equal to those found in previous studies in patients suffering from dry-eye disease. The alterations in the diabetic tears were correlated with the duration of the diabetic disease. With longer disease, history changes in the tear protein patterns increased. With the course of the disease some protein peaks appeared that are not present in healthy persons. Our study shows that the analysis of electrophoretic tear protein patterns is a new non-invasive approach in the early diagnosis and analysis of the pathogenesis of diabetes induced ocular surface disease.  相似文献   
87.
A series of novel 2-phenyl-3-substituted quinazolin-4(3H)-ones have been synthesized by treating methyl-N-(2-phenyl quinazolin-3-yl-4(3H)-one) dithiocarbamate with different amines, the starting material dithiocarbamate was synthesized from anthranilic acid. The title compounds were investigated for analgesic, anti-inflammatory and antibacterial activities. All the test compounds exhibited significant activity, the compounds A1, A2 and A3 shown more potent analgesic activity, and the compound A3 shown more potent anti-inflammatory activity than the reference standard diclofenac sodium.  相似文献   
88.
Bioassay-guided fractionation of a root bark extract of Symphonia globulifera has yielded, in addition to stigmasterol, two new xanthones with isoprenoid units, named globulixanthones A (1) and B (2). The structures of these compounds have been elucidated by spectroscopic means. They possess significant cytotoxicity in vitro against the KB cell line.  相似文献   
89.
BACKGROUND: Quantitative assessment of multiple sexual partnerships and concurrency may help to elucidate the large observed differences in the prevalence of AIDS among population subgroups and countries. GOAL: The goals of the study were (1) to develop a global scale of dynamic patterns of sexual partnerships, including concurrency with new partners and stable concurrency; (2) to apply this scale to three Caribbean regions characterized by different cumulative rates of incidence of AIDS; and (3) to compare the concurrency rates given by this scale with those of other published methods. STUDY DESIGN: We defined an individual scale based on 6 patterns of sexual behavior over the previous 12-month period, by using a simple algorithm to combine 7 variables. We then applied this scale to cross-sectional data collected from men living in three French Caribbean regions: Guadeloupe, Martinique, and Guyana. RESULTS: We found that all adults of all age classes in the three regions studied frequently had multiple (>2) and concurrent partnerships. The patterns of sexual behavior in the three regions were consistent with the respective cumulative incidence rates of AIDS, and a lower rate of concurrency with new partners and a higher rate of stable partnership concurrency were noted in Martinique, especially among 45- to 59-year-olds. The rate of concurrent partnerships was found to depend on the criteria used to define them and on the observation period (a given moment, or a defined period). Our definition gave a higher rate of concurrency than previously published indicators. CONCLUSION: The proposed scale can be applied to easy-to-collect data in cross-sectional population surveys and takes into account a wide variety of behaviors, including different types of concurrency.  相似文献   
90.
BACKGROUND: Polyphenolic procyanidins are abundant flavonoid polymers in Western diets. In vitro biological activity has been reported for these compounds, but activity in vivo depends on the amount and chemical nature of the flavonoids reaching the gastrointestinal tract. Degradation of procyanidins under simulated gastric conditions at pH 2.0 has been reported in vitro. OBJECTIVE: The objective was to examine whether depolymerization of procyanidins occurs in the stomach of human subjects in vivo. DESIGN: After an overnight fast, 6 healthy subjects (3 men and 3 women) consumed 500 mL of a cocoa beverage containing 733 mg procyanidin polymers and 351 mg structurally related flavanol monomers. With the use of a nasogastric tube, stomach contents were collected every 10 min after beverage ingestion until the stomach was emptied. Flavanols and procyanidins (up to pentamers) were quantified by normal and reversed-phase HPLC. RESULTS: In all subjects, gastric transit lasted approximately 50-60 min. No change in the HPLC profile of procyanidins was observed during this period, showing that procyanidins were remarkably stable in the stomach environment. CONCLUSION: The results suggest that most ingested procyanidins reach the small intestine intact and are available for absorption or metabolism.  相似文献   
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