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91.
In an effort to minimize surgical and visual morbidity of cryotherapy for retinopathy of prematurity (ROP), 18 eyes of 13 patients with 3 to 7 clock hours of stage 3 ROP with "plus" disease were treated by cryotherapy applications limited to the avascular retina adjacent to the areas of stage 3 disease. In 17 of 18 eyes, this limited use of cryotherapy was sufficient to cause regression of ROP without further treatments. After at least 3 months follow-up, ROP outcome showed a normal macular appearance in 16 eyes; two eyes developed macular dragging; no retinal detachments occurred.  相似文献   
92.
In two headache questionnaire surveys we inquired about the occurrence of headache in the mothers, fathers, siblings and children of the respondents. In total, 633 people completed valid questionnaires, 260 in the first survey and 373 in the second. The hypothesis was that familial headache occurrence would be positively associated with headache frequency. In each survey, the regression of headache frequency on the number of parents having headache was highly significant. Neither sex nor the sibling and children variables were significant predictors. In the cross-tabulations of the parental occurrence of headache with headache frequency we saw a clear "break-point" between the "no headache" and the headache frequency categories studied. For the final analyses the dichotomy "headache/no headache" was related in fourfold tables to headache occurrence in the father and the mother separately, and to the number of headache parents. The positive associations were not simply due to the large number of migraine cases since they remained after removing the migraineurs.  相似文献   
93.
Abnormalities of cerebral oxidative metabolism were investigated in "animal models" of Parkinson disease by in situ optical measurements of local cerebral blood volume and cytochrome oxidase redox shifts in rats two weeks after unilateral 6-hydroxydopamine lesions of the substantia nigra with or without interruption of ascending noradrenergic pathways. The data demonstrate oxidative metabolic dysfunction of ipsilateral cerebral hemispheres caused by lesions that involve both dopaminergic and noradrenergic systems but not when dopaminergic neurons only are affected. We speculate that the dementia of Parkinson disease may be more prevalent when degeneration of catecholaminergic systems is widespread and not restricted to the dopaminergic system.  相似文献   
94.
Validity of the tritiated water assay technique for tyrosine hydroxylase activity as a qualitative method was demonstrated with mushroom tyrosinase. Using this method, isolated murine melanoma "tyrosinase" (L-dopa oxidase) showed no tyrosine hydroxylase activity. This finding supports previous studies in our laboratory which used a variety of histochemical and biochemical methods. The nonenzymatic production of tritiated water caused by tritium exchange with hydrogen peroxide complicates the use of the tritiated water assay technique with crude systems, since hydrogen peroxide is generated by a variety of oxidase reactions. For this reason, previous studies using the tritiated water assay technique with crude systems are ambiguous.  相似文献   
95.
Poly(ADP-ribose) polymerase-1 (PARP-1) is a nuclear enzyme, activated by DNA strand breaks to participate in DNA repair. Overactivation of PARP by cellular insults depletes its substrate NAD(+) and then ATP, leading to a major energy deficit and cell death. This mechanism appears to be prominent in vascular stroke and other neurodegenerative processes in which PARP gene deletion and PARP-inhibiting drugs provide major protection. Cell death associated with PARP-1 overactivation appears to be predominantly necrotic while apoptosis is associated with PARP-1 cleavage, which may conserve energy needed for the apoptotic process. Novel forms of PARP derived from distinct genes and lacking classic DNA-binding domains may have nonnuclear functions, perhaps linked to cellular energy dynamics.  相似文献   
96.
Forty Bosnian refugee couples living in the United States completed a translated version of the PTSD Symptom Scale—Self Report, the Behavioral Acculturation Scale, the Marital Satisfaction Inventory—Revised, and a demographic questionnaire. Posttraumatic stress disorder (PTSD) symptomatology was the best predictor of marital functioning and was related negatively to acculturation. After controlling for PTSD, acculturation did not predict marital functioning. Wives' marital satisfaction was best predicted by husbands' PTSD, husbands' acculturation, and their own PTSD. Husbands' marital satisfaction was not predicted significantly by any of these variables. These findings suggest several implications for mental health professionals dealing with refugees and other traumatized populations.  相似文献   
97.
OBJECTIVE: To evaluate radiotherapy dose and length of treatment in the control of early stage nasopharyngeal carcinoma (NPC) treated with a combination of external radiotherapy and brachytherapy, MATERIALS & METHODS: We reviewed the records of 133 patients with early stage nasopharyngeal carcinoma (stage I or II, AJC/UICC staging system) who received definitive radiotherapy in Chang Gung Memorial Hospital from 1979 to 1991. The median follow-up time was 7.1 years with a minimum of 2 years. All patients were treated with megavoltage external radiotherapy to the nasopharynx area (63-72 Gy) followed by high dose rate intracavitary brachytherapy (5-16.5 Gy in one to three fractions, spaced 1-2 weeks apart). The median total dose and time of irradiation was 75 Gy (69.8-81.4 Gy) and 11.6 weeks (7.8-20 weeks) respectively. Survival analysis was used to examine the effect of several variables on prognosis. RESULTS: The 5-year rates were 86.4% for local control, 84.7% for disease free survival, 88.5% for actuarial survival and 84.2% for overall survival. The treatment group (combination of time and dose of irradiation) was the most important prognostic factor according to Cox's proportional hazard model. Patients receiving radiation at a total dose of < or = 75 Gy completed in < 12 weeks showed the best prognosis. CONCLUSION: Treatment time and total treatment dose are both important factors in treating early stage NPC. Decreasing the total radiation time to < 12 weeks and not exceeding a radiation dose of 75 Gy gave the best results.   相似文献   
98.
OBJECTIVE: A retrospective review of appendectomies performed at the University of Kansas Medical Center between January 1, 1989, and January 1, 1994, was conducted. In addition, the literature evaluating effectiveness of incidental appendectomy in preventing future operation and morbidity from appendicitis was reviewed. The results of the two reviews were analyzed to formulate guidelines for the appropriateness of performing incidental appendectomy in association with other operative procedures. METHOD: A retrospective review of results of appendectomies performed in 460 patients at the University of Kansas Medical Center with analysis of operative findings, pathology of the removed appendix and operative complications was performed. These results were compared with those of a systematic review of the literature utilizing a Medline search relating to the subject of incidental appendix removal. RESULTS: Two hundred sixty-one incidental appendectomies were performed in this study of 460 patients (60%). The procedure was most commonly performed with total abdominal hysterectomy (56%), followed by oophorectomy (15%) and exploratory laparotomy (11%). Morbidity was minimal at all ages. Microscopic pathology was found in 25% of the cases. CONCLUSION: The data from the current survey and literature review support incidental removal of the appendix in the young patient (< 35 years old). In patients 35-50 years old the literature is controversial, and the patient's clinical condition and judgment of the operating surgeon should determine whether incidental appendectomy should be performed. However, routine incidental appendectomy cannot be justified in patients greater than age 50.  相似文献   
99.
Krithika Rajagopalan  PhD    Linda Abetz  MA    Polyxane Mertzanis  MPH    Derek Espindle  MA    Carolyn Begley  OD  MS    Robin Chalmers  OD    Barbara Caffery  OD  MS    Christopher Snyder  OD  MS    J. Daniel Nelson  MD    Trefford Simpson  PhD    Timothy Edrington  OD  MS 《Value in health》2005,8(2):168-174
OBJECTIVE: The purpose of this study was to compare the discriminative properties of two generic health-related quality of life (QoL) instruments (SF-36 and EQ-5D) and a newly developed disease-specific patient-reported outcomes instrument (Impact of Dry Eye on Everyday Life (IDEEL)) to distinguish between different levels of dry eye severity. METHODS: Assessment of 210 people: 130 with non-Sjogren's Keratoconjunctivitis Sicca (non-SS KCS), 32 with Sj?gren's Syndrome (SS) and 48 controls; comparison of SF-36, EQ-5D, and IDEEL age-adjusted data by dry eye severity levels. Severity was assessed based on diagnosis (non-SS KCS, SS, control), patient-report (none, very mild, mild, moderate, severe, extremely severe) and clinician-report (none, mild, moderate, severe). RESULTS: Discriminative validity results were consistent for all instruments. Significant differences between severity levels were found with most SF-36 scales (P < 0.05), all EQ-5D scales (P < 0.05), and all IDEEL scales (P < 0.0001), except for Treatment Satisfaction. IDEEL scales consistently outperformed the generic QoL measures regardless of the severity criterion used. Most SF-36 scales outperformed the EQ-5D QoL scale, but the EQ-5D visual analog scale outperformed the SF-36 scales, except for General Health Perceptions. CONCLUSIONS: The disease-specific IDEEL scales are better able to discriminate between severity levels than the majority of the generic QoL scales. Preliminary evidence demonstrates that the IDEEL will be sensitive to QoL changes over time, although further testing in controlled longitudinal studies is needed.  相似文献   
100.
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