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81.
82.
Seven eyes of seven patients with visually disabling postkeratoplasty astigmatism underwent arcuate keratotomy to reduce astigmatism. Keratotomy length was prospectively determined by comparing the corneal shape change needed by each patient with shape changes in cadaver eyes induced by arcuate keratotomy. Keratograph ring ovality quantified corneal shape change. Keratotomies were placed in the wound interface using a diamond knife with blade length set to 100% of corneal thickness. Prekeratotomy keratometric astigmatism was 9.27 +/- 2.14 D (mean +/- SD), and at 2.0 to 18.4 months after keratotomy, astigmatism was 2.75 +/- 2.25 D (mean +/- SD). All corneas had decreased keratometric astigmatism and less oval keratoscope rings. Five corneas had 3.00 D or less residual keratometric astigmatism. Change in ring ovality was significantly correlated with keratotomy length and keratometric astigmatism change. The utility of keratoscope ring ovality as a corneal topography metric was demonstrated by systematically investigating the response to arcuate keratotomy.  相似文献   
83.
LY354740 is a potent mGlu2/3 agonist with a limited oral bioavailability. Its alanyl prodrug, LY544344, showed high affinity to the intestinal peptide transporter PEPT1, and improved the oral bioavailability of LY354740 in various animal models. The aim of the present study was to investigate the mechanism of in vivo absorption of the dipeptidic prodrug LY544344. The permeabilities of LY544344 and LY354740 were examined in the rat in situ single‐pass intestinal perfusion model. The intestinal absorptive flux of LY354740 was shown to be very low in comparison with LY544344. The absorptive flux of LY544344 could best be described by a Michaelis–Menten process in parallel with a linear process. The estimated parameters were: Jmax = 26.7 × 10?5 µmol/(cm2‐s), Km = 2.6 mM. The absorptive permeability of LY544344 was reduced to approximately 5% of control in the presence of excess Gly‐Sar, a known PEPT1 substrate. Intracellular accumulation of LY354740 and LY544344, estimated postperfusion, showed high levels of LY354740 over LY544344 at all perfusate concentrations studied. However, there was a decline in the intracellular ratio of LY354740 to LY544344 at higher concentrations, suggesting that the metabolic activation to release LY354740 is saturable. © 2009 Wiley‐Liss, Inc. and the American Pharmacists Association J Pharm Sci 99: 1574–1581, 2010  相似文献   
84.
Coronary artery fistula is often considered to be a benign and rare congenital anomaly. It is usually an incidental finding encountered during routine cardiac catheterization. We report a case of a patient presenting with endocarditis involving a large coronary artery fistula connecting an aneurysmal circumflex coronary artery to the coronary sinus. The diagnosis was initially made by echocardiography and confirmed by cardiac catheterization. In addition, we briefly discuss the literature on management of this coronary anomaly.  相似文献   
85.
The nutritional and growth effects on children following a bone marrow transplant (BMT) have not been well documented. The purpose of this study was to describe the growth patterns of young children during the first year following BMT. A retrospective chart review was used to examine the nutritional status of 25 young children, 1 to 6 years of age, who received an allogeneic BMT. Nutritional data were reviewed prior to BMT and at 3, 6, 9, and 12 months following BMT. The mean weight gain was 2.5 kg with a median weight gain of 2.3 kg (range, -1.2 to 9.4 kg). The mean height gain was 7 cm with a median height gain of 7.4 cm (range, 1.2 to 16.8 cm). Growth related to gender, age, and incidence of infection was similar to the overall average; however, children with graft-versus-host disease revealed poor weight and height gain. Nurses must learn to recognize patients at nutritional risk and intervene when necessary. More research is needed to address specific nutritional needs of the pediatric BMT patient.  相似文献   
86.
A patient-centered paradigm for clinical research and medical care is presented as a solution to the problem of declining innovation and increasing costs and development time in the pipeline for new therapies. Fundamental differences in values and motivations among scientists, clinicians, industry sponsor, and patients in neurotherapeutics provide a framework for analysis of ethical conflicts and the loss of public confidence in medical research. Parkinson advocates’ views on clinical trial participation, perceived risks and benefits, placebo controls, and sham surgery are presented. These views reflect the sense of urgency and the unique perspective that comes from living with this progressive, debilitating condition full time. A patient-centered paradigm that includes authentic voices of patients as collaborators at every stage of development will help to resolve conflicts, build trust, recruit trial participants, and accelerate new therapies. Key elements are adaptive clinical trial methods and the development of information technology for the assessment of outcomes and surveillance of safety over the life cycle of a medical product. Supported by the Parkinson’s Disease Foundation, the Parkinson Pipeline Project is a grassroots group of Parkinson’s patients whose goal is to represent an authentic voice for patients in the treatment development process. This group promotes education and communication between members of the Parkinson’s community and active stakeholders in medical research, industry, and regulatory agencies. Its members are an example of a new breed of knowledgeable consumers, armed with first-hand access to research findings and reinforced by on-line connections to like-minded peers throughout the world.  相似文献   
87.
88.
Allogeneic hematopoietic stem cell transplantation (HSCT) is established therapy for selected patients with acute leukemia. After transplantation, antileukemic immune responses are believed to eliminate residual leukemia cells and decrease the likelihood of relapse. However, the clinical effect of successful antigen-specific immune reconstitution after HSCT on the likelihood of leukemic relapse and overall survival is not known. Pediatric recipients of unrelated cord blood transplants who underwent transplantation for acute leukemia were sequentially evaluated for their development of antigen-specific T-lymphocyte immunity to herpes viruses. The clinical effect of a positive antigen-specific response on relapse-free survival was determined. The presence of an antigen-specific response resulted in a relapse-free survival advantage (P = .0001), which was primarily due to a decrease in leukemic relapse (P = .003). Proportional hazards modeling for time to relapse and time to relapse or death defined 3 variables that were strongly associated with a poor outcome: female gender, poor remission status before transplantation, and negative antigen-specific T-lymphocyte proliferation. Notably neither acute nor chronic graft-versus-host disease had any effect on the incidence of leukemic relapse. Successful antigen-specific immune reconstitution after unrelated cord blood transplantation results in decreased leukemic relapse and improved overall survival.  相似文献   
89.
Sclerosing stromal cell tumors of the ovary are an uncommon neoplasm that usually does not produce hormonal imbalances. Most patients showing a hormonal effect from this lesion have had menstrual cycle disturbances. Infertility and endometrial hyperplasia have also been described. One other reported case had masculinizing effects. Other authors have documented elevated levels of both estrogenic and androgenic hormones that corrected after surgery. A case of a pregnant 27-year-old Caucasian with hirsutism on her chin and neck and a male suprapubic hair pattern is presented. Elevated androstenedione, dehydroepiandrosterone, and free testosterone levels were present. A 3-cm left ovarian mass was excised and identified as a sclerosing stromal tumor. The histologic features included a pseudolobular pattern with focal areas of sclerosis and a two-cell population of spindled and polygonal cells. Immunohistochemical studies showed a positive vimentin reaction, weakly positive desmin and muscle-specific actin stains, and a negative cytokeratin stain. Following surgery the hormone levels returned to normal and the hirsutism resolved. A normal female infant without evidence of masculinization was delivered from the patient at term.  相似文献   
90.
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