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31.
32.
Dynamic rotation is a computer-controlled therapy technique utilizing an automated multileaf collimator in which the radiation beam shape changes dynamically as the treatment machine rotates about the patient so that at each instant the beam shape matches the projected shape of the target volume. In simple dynamic rotation, the dose rate remains constant during rotation. For optimized dynamic rotation, the dose rate is varied as a function of gantry angle. Optimum dose rate at each gantry angle is computed by linear programming. Wedges can be included in the optimized dynamic rotation therapy by using additional rotations. Simple and optimized dynamic rotation treatment plans, with and without wedges, for a pancreatic tumor have been compared using optimization cost function values, normal tissue complication probabilities, and positive difference statistic values. For planning purposes, a continuous rotation is approximated by static beams at a number of gantry angles equally spaced about the patient. In theory, the quality of optimized treatment planning solutions should improve as the number of static beams increases. The addition of wedges should further improve dose distributions. For the case studied, no significant improvements were seen for more than 36 beam angles. Open and wedged optimized dynamic rotations were better than simple dynamic rotation, but wedged optimized dynamic rotation showed no definitive improvement over open beam optimized dynamic rotation. 相似文献
33.
H. R. Rosen W. Feil G. Novi G. Zöch S. Dahlberg R. Schiessel 《International journal of colorectal disease》1994,9(4):184-186
Continence following the gracilis stimulated neosphincter reconstruction after total rectal excision is inferior to that obtained in the presence of an intact anal canal. We describe a modification of the alpha loop in which the tendon is brought through the belly of the gracilis muscle. The results in three patients are presented.
Résumé La reconstruction sphinctérienne après excision totale du rectum au moyen d'un néosphincter fait d'un muscle gracilis stimulé donne des résultats sur le plan de la continence inférieurs à ceux obtenus en présence d'un canal anal intact. Nous décrivons une modification de l'anse alpha dans laquelle le tendon est fixé après avoir traversé la sangle de muscle gracilis. Les résultats de trois patients sont rapportés.相似文献
34.
Depressed patients were interviewed at two different severity levels in the course of their illness about both problematic and neutral topics, and their speech behavior was analyzed in terms of speech activity and silences. Lowered speech activity and increased silences occurred at higher severity levels and also during problematic communication content, suggesting the mediation of cognitive factors as postulated by Beck's cognitive model of depression. 相似文献
35.
There has been a traditional reluctance to remove a subluxed (ectopic) lens because of the high surgical risk. The use of closed intraocular microsurgical techniques, however, now allows greater intraoperative control with few complications. The authors present the results of subluxed lens extraction, by limbal or pars plana lensectomy, in 44 eyes of 24 patients, in which the indication for surgery was lens subluxation causing a reduction in visual acuity or uncorrectable refractive error. Visual acuity was improved in all cases after surgery, with no significant complications. Patients with reduced visual acuity secondary to ectopic lenses have a good visual prognosis after lensectomy using a closed intraocular microsurgical technique. 相似文献
36.
Lectin-like cell adhesion molecule 1 mediates leukocyte rolling in mesenteric venules in vivo 总被引:54,自引:3,他引:51
During the inflammatory response, granulocytes and other leukocytes adhere to and emigrate from small venules. Before firm attachment, leukocytes are observed rolling slowly along the endothelium in venules of most tissues accessible to intravital microscopy. The molecular mechanism underlying this early type of leukocyte-endothelial interaction is unknown. Leukocyte rolling was investigated in venules (diameter, 40 microns) of the exposed rat mesentery. Micro-infusion of a recombinant soluble chimera (LEC-IgG) of the murine homing receptor lectin-like cell adhesion molecule 1 (LEC-CAM 1; gp90MEL) into individual venules reduced the number of rolling leukocytes by 89% +/- 2% (mean +/- SEM, n = 20 venules), while a similar CD4 chimera (CD4-IgG) had no effect (inhibition 14% +/- 7%, n = 25). Rolling was also greatly reduced by a polyclonal serum against LEC-CAM 1 (inhibition 84% +/- 3%, n = 35); preimmune serum was ineffective (11% +/- 13% inhibition, n = 28). These findings indicate that LEC-CAM 1 mediates the adhesive interaction underlying leukocyte rolling and thus may play an important role in inflammation and in pathologic conditions involving leukocytes. 相似文献
37.
Background
Job satisfaction is important for nursing home staff and nursing home management, as it is associated with absenteeism, turnover, and quality of care. However, we know little about factors associated with job satisfaction and dissatisfaction for nursing home workers. 相似文献38.
Combined open and laparoscopic approach to chronic pain following open inguinal hernia repair 总被引:1,自引:0,他引:1
Introduction: Chronic groin pain is the most common long-term complication after open inguinal hernia repair. Traditional surgical management
of the associated neuralgia consists of injection therapy followed by groin exploration, mesh removal, and nerve transection.
The resultant hernia defect may be difficult to repair from an anterior approach. We evaluate the outcomes of a combined laparoscopic
and open approach for the treatment of chronic groin pain following open inguinal herniorrhaphy. Methods: All patients who underwent groin exploration for chronic neuralgia after a prior open inguinal hernia repair were prospectively
analyzed. Patient demographics, type of prior hernia repair, and prior nonoperative therapies were recorded. The operation
consisted of a standard three trocar laparoscopic transabdominal preperitoneal hernia repair, followed by groin exploration,
mesh removal, and nerve transection. Outcome measures included recurrent groin pain, numbness, hernia recurrence, and complications.
Results: Twelve patients (11 male and 1 female) with a mean age of 41 years (range 29–51) underwent combined laparoscopic and open
treatment for chronic groin pain. Ten patients complained of unilateral neuralgia, one patient had bilateral complaints, and
one patient complained of orchalgia. All patients failed at least two attempted percutaneous nerve blocks. Prior repairs included
Lichtenstein (n=9), McVay (n=1), plug and patch (n=1), and Shouldice (n=1). There were no intraoperative complications or wound infections. With a minimum of 6 weeks follow up, all patients were
significantly improved. One patient complained of intermittent minor discomfort that required no further therapy. Two patients
had persistent numbness in the ilioinguinal nerve distribution but remained satisfied with the procedure. Conclusions: A combined laparoscopic and open approach for postherniorrhaphy groin pain results in good to excellent patient satisfaction
with no perioperative morbidity. It may be the preferred technique for the definitive management of chronic neuralgia after
prior open hernia repair. 相似文献
39.
40.
Development of cDNA probes for typing group A bovine rotaviruses on the basis of VP4 specificity. 下载免费PDF全文
Dot and Northern (RNA) blot hybridization assays were developed for the P typing of group A bovine rotaviruses (BRV) by using cDNA probes prepared from gene segment 4. The probes were prepared by polymerase chain reaction amplification of hyperdivergent regions (nucleotides 211 to 686) of BRV strain UK, IND, NCDV, and Cr VP4 cDNA by using specific oligonucleotide primers. The probes were P type specific (VP4) and exhibited little or no cross-reactivity with double-stranded RNA from heterologous rotavirus P types. Our studies indicate that at least three P types, as defined by polymerase chain reaction-derived VP4 gene probes from the UK, NCDV, and Cr strains, exist among the seven BRV isolates tested. 相似文献