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81.
82.
Objective: To explore a 5-year comparison of disparities in intravenous t-PA (IV t-PA) use among acute ischemic stroke (AIS) patients based on race, gender, age, ethnic origin, hospital status, and geographic location. Methods: We extracted patients’ demographic information and hospital characteristics for 2010 and 2014 from the New York Statewide Planning and Research Cooperative System (SPARCS). We compared disparities in IV t-PA use among AIS patients in 2010 to that in 2014 to estimate temporal trends. Multiple logistic regression was performed to compare disparities based on demographic variables, hospital designation, and geographic location. Results: Overall, there was approximately a 2% increase in IV t-PA from 2010 to 2014. Blacks were 15% less likely to receive IV t-PA compared to Whites in 2014, but in 2010, there was no difference. Patients aged 62-73 had lower odds of receiving IV t-PA than age group ≤61 in both 2010 and 2014. Designated stroke centers in the Lower New York State region were associated with reduced odds of IV t-PA use in 2010 while those located in the Upper New York State region were associated with increased odds of IV t-PA use in both 2010 and 2014, compared to their respective nondesignated counterparts. Gender, ethnic origin, and insurance status were not associated with IV t-PA utilization in both 2010 and 2014. Conclusion: Overall IV t-PA utilization among AIS patients increased between 2010 and 2014. However, there are evident disparities in IV t-PA use based on patient's race, age, hospital geography, and stroke designation status.  相似文献   
83.

Background

Vitreous substitutes presently in use for intraoperative tamponade are perfluorocarbon liquids (PFCL) and for post operative tamponade are silicon oil (SO), sulphur hexafluoride (SF6) and perfluorocarbon gas (PFC). Several factors are important for a thorough understanding of each of these vitreous substitutes. The absorption or necessity for removal, indications for use (including clinical studies and special surgical methods), additives and complications of use have to be considered.

Methods

Three port standard pars plana vitrectomy was performed in 60 consecutive cases requiring intra-vitreal intervention. PFCL was used intra-operatively in 30 cases (PFCL group and X group). The eyes were implanted with SO (silicon oil subgroup), PFC (C3F8 sub-group) and SF6 (SF6 sub-group) in twenty cases each. Apart from best corrected visual acuity (BCVA), the retinal status and the longevity of gas when used, changes and reaction in both the anterior and posterior segments were noted.

Result

The difference of postoperative BCVA in the PFCL and non-PFCL groups was statistically significant with p < 0.001. In both the PFCL and non-PFCL groups the difference between preoperative and postoperative BCVA was statistically significant with p < 0.0001. All three vitreous substitutes studied are effective given the case where they had been utilised.

Conclusion

PFCL is invaluable in the management of complicated retinal detachment (RD). Where a vitreous microsurgery is indicated, the visual outcome is good. SF6 is useful for short-term tamponade. Silicon oil and C3F8 are useful for longer tamponade.Key Words: Tamponade, Perfluorocarbon liquids, Silicon oil, Sulphur hexafluoride, Perfluorocarbon gas, Retinal detachment  相似文献   
84.

Background

Proliferative vitreo-retinopathy (PVR) is the most common cause of failed repair of a primary rhegmatogenous retinal detachment (RRD). The success rates for the surgery of complicated RRD has doubled with improved vitreous techniques from 35–40% to approximately 65–75% at six months. However, despite these advances, recurrent vitreo-retinal traction leads to re-detachment in more than one-fourths of the initially successful cases. The use of adjunctive treatments to prevent cellular proliferation holds promise for the prevention of PVR or recurrences after surgery. One focus has been on the use of intra-vitreal antimetabolites to prevent the occurrence of PVR.

Methods

Thirty patients of complicated retinal detachment associated with PVR, C1 or more were managed by vitreo-retinal (VR) surgery with the addition of 250 μg / ml of 5-fluorouracil (5FU) and 1 IU / ml of low molecular weight heparin (LMWH) to the vitreous infusion. The patients were examined for any evidence of PVR till 180 days as also for any systemic or other ophthalmic complication.

Result

Out of the 30 cases in the study group, 25 (83.34%) cases had retinal settlement at the end of six weeks, which is similar to the outcomes of conventional VR surgery. There was no case of any serious complication.

Conclusion

The addition of LMWH and 5FU did not enhance the outcome of VR surgery.Key Words: Proliferative vitreo-retinopathy, Rhegmatogenons retinal detachment, 5-fluorouracil, Low molecular weight heparin  相似文献   
85.
The aim of the study was to determine the prevalence of crown fractures of permanent incisors in schoolchildren aged 7-11 years from the town of Plovdiv. MATERIAL AND METHODS: The present study included 2572 children (1287 boys and 1285 girls) at the age of 7 to 11 years from Plovdiv. A modification of the WHO classification for reporting crown fractures was used. Examinations were performed only of the upper and lower incisors, in the classrooms at daylight. Treatments of the fractured teeth after the trauma were also registered. The results were analysed statistically by calculating the chi-square to determine if there was any significant difference between the variables. RESULTS: The prevalence of crown fractures of permanent teeth in children aged 7-11 years from Plovdiv was 8.67 +/- 0.55%. The crown fracture prevalence in boys was significantly higher than that in the girls for all examined children. Most of the children had only one fractured tooth (82.96 +/- 2.52%). The prevalence of the incisor crown fractures by teeth was 1.28 +/- 0.08%. The greatest number of fractured teeth were located in the maxilla (88.20 +/- 1.99%). Most often the fractures involved only the enamel or the enamel and dentine while complicated crown fractures with pulpal exposure were found in 5.32 +/- 1.38%. Most of the fractured teeth were left untreated (84.79 +/- 2.40%). CONCLUSIONS: The prevalence of permanent incisor crown fractures in children aged 7-11 years from Plovdiv was 8.67 +/- 0.55%; and by teeth--1.28 +/- 0.08%. Children with only one fractured tooth were the greatest part of all injured children in the study. There were significantly more maxillary teeth fractures, with predominance of uncomplicated crown fractures in the permanent teeth. Treated fractured teeth were very few. Treatment was needed for 78.92 +/- 2.73% of all registered fractured incisors.  相似文献   
86.
Traditional Eastern medicine has had a successful existence for a long time and has provided functional paths for curing disease. However, some scientists do not accept acupuncture, primarily because the meridian system lacks a physical anatomical basis. To date, scientific theories have not been able to explain the functional paths used by traditional Eastern medicine to cure disease. According to Western medicine, no known anatomical foundation exists for the meridians and unknown nervous, circulatory, endocrine, and immune mechanisms mediate the effects of acupuncture. In the early 1960s, only one hypothesis was proposed to explain the anatomical basis of the meridians. By using different experimental approaches during the past 10 years, the number of scientific papers that report the discovery of different anatomical and physiological evidence confirming the existence of an anatomical basis for the meridian system has increased. Morphological science is greatly challenged to offer a new biomedical theory that explains the possible existence of new bodily systems such as the primo vascular system (PVS). The PVS is a previously unknown system that integrates the features of the cardiovascular, nervous, immune, and hormonal systems. It also provides a physical substrate for the acupuncture points and meridians. Announcements of the morphological architectonics and the function of the PVS fundamentally changed the basic understanding of biology and medicine because the PVS is involved in the development and the functions of living organisms. We propose a new vision of the anatomical basis for the PVS and the vital energy—called “Qi”—as an electromagnetic wave that is involved very closely with the DNA in the PVS. DNA provides genetic information and it functions as a store of information that can be obtained from the electromagnetic fields of the environment. The PVS is the communication system between living organisms and the environment, and it lies at the lowest level of life. The theory of the PVS could be a good basis for forming a new point of view of Darwin's evolutionary theory. Discoveries in morphological theory—such as discoveries with respect to the PVS—have not been made since the 18th century. For that reason, the PVS needs more attention.  相似文献   
87.
88.
Data about the sensitivity and the specificity of the items included in the diagnostic criteria for migraine and tension type headache (TTH) in children is limited and sometimes controversial. Aim: To evaluate the diagnostic value of characteristics of migraine and TTH included in the diagnostic criteria of ICHD–II and according to results to suggest additional criteria for diagnostic differentiation of primary paediatric headache. Patients and methods: The investigation consisted of an epidemiological school‐based study (1029 pupils completed the study and 412 had chronic or recurrent headache) and a clinical study conducted in Paediatric Neurology Ward and outpatient clinic (203 patients with chronic or recurrent headache). Inclusion criterion was at least two episodes of headache during the last year. Exclusion criteria were: headache occurring only during acute infections; withdrawal of informed consent. ICHD – II was used to classify headache. The diagnostic value of characteristics of migraine and TTH was measured using sensitivity, specificity, odds ratio and area under receiver operating characteristic curve (AUC). Results: Regarding the AUC, the best diagnostic items for migraine are: moderate or severe intensity or only severe intensity, pain aggravation by physical activity, pulsating quality, respectively, for TTH – no photophobia, no nausea, no aggravation by physical activity, mild or moderate intensity and non‐pulsating quality. The most significant symptom for increasing the migraine risk was pulsating pain and the most significant items for TTH risk were no photophobia, bilateral location and no nausea. Family history of migraine also increased migraine risk and could be either included in the diagnostic criteria for migraine or recommended as additional item in differentiating migraine and TTH with overlapping diagnostic criteria. According to AUC, we could recommend changing the content of the item of intensity for migraine as only severe intensity.  相似文献   
89.
90.
Rod-cone degenerations, for example, retinitis pigmentosa are leading causes of blindness worldwide. Despite slow disease progression in humans, vision loss is inevitable; therefore, development of vision restoration strategies is crucial. Among others, promising approaches include optogenetics and prosthetic implants, which aim to bypass lost photoreceptors (PRs). Naturally, the efficacy of these therapeutic strategies will depend on inner retinal structural and functional preservation. The present study shows that in photoinducible I307N rhodopsin mice (Translational Vision Research Model 4 [Tvrm4]), a 12k lux light exposure eliminates PRs in the central retina in 1 week, but interneurons and their synapses are maintained for as long as 9 weeks postinduction. Despite bipolar cell dendritic retraction and moderate loss of horizontal cells, the survival rate of various cell types is very high. Significant preservation of conventional synapses and gap junctions in the inner plexiform layer is also observed. We found the number of synaptic ribbons to gradually decline and their ultrastructure to become transiently abnormal, although based on our findings intrinsic retinal architecture is maintained despite complete loss of PRs. Unlike common rodent models of PR degeneration, where the disease phenotype often interferes with retinal development, in Tvrm4 mice, the degenerative process can be induced after retinal development is complete. This time course more closely mimics the timing of disease onset in affected patients. Stability of the inner retina found in these mutants 2 months after PR degeneration suggests moderate, stereotyped remodeling in the early stages of the human disease and represents a promising finding for prompt approaches of vision restoration.  相似文献   
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