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111.
Structure-Activity Relationships of Nefopam Hydrochloride An X-ray study of (?)-nefopam hydrochloride ( 1 ) (P21/c, a = 1176.1, b = 773.9, c = 1689.7 pm, β = 97.43°, Z = 4) shows that the heterocyclic ring has two structurally simple features: Five atoms (2–6) form the C5 fragment of a cyclohexane ring, while another five atoms (2, 1, 10a, 6a and 6) lie within the plane of the fused benzene ring. The two benzene rings are almost perpendicular to each other, which is remarkably different from the structurally related benzodiazepines. The structure of 1 is practically identical with that found for (-)-nefopam hydrochloride monohydrate, a fact which is discussed under the aspect of conformational rigidity. Nefopam can be taken as a model substance for serotonin agonists and antagonists. As a common structural feature these compounds have an aliphatic amino group which lies (or can be easily placed) at a distance of about 600 pm from the center of the aromatic system and nearly within the plane of the system. 相似文献
112.
Pediatric patients with achondroplasia: CT evaluation of the craniocervical junction 总被引:2,自引:0,他引:2
Twenty-six patients (4 months to 6 years old) with achondroplasia complicated by sleep apnea and/or other neurologic manifestations underwent plain computed tomography (CT) of the craniocervical junction; six also underwent CT myelography. For objectification, multiplanar reconstruction was used to complement axial plane measurements by providing coronal and sagittal measurements; multiplanar reconstruction also improved perception of the longitudinal relationships between the brain stem and subarachnoid space. A narrow subarachnoid space was found in all 26 patients; marked cord compression was present in nine, six of whom underwent CT myelography. These six had marked focal obliteration of the subarachnoid space on both plain CT and CT myelography. Since the subarachnoid space immediately above and below the craniocervical junction is normally capacious, when marked constriction was present, no additional information could have been gained from CT myelography. Thus, plain CT was shown to be sufficient for surgical planning (suboccipital decompression) in nine patients with cord compression due to achondroplasia. 相似文献
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114.
Medical schools put little emphasis upon education on public health, even though public health has played an important role in this century. One way to harness its benefit in order to improve global health in the 21st century is to globally share lectures on public health through the Internet. We have developed the Supercourse comprising of web-based learning modules on epidemiology in a standardized format with the size of each web page less than 10 kilobytes. A cross-sectional observational study was conducted to investigate the association of the perception of the access speed to Web-based lectures by teachers with their perception of lecture quality. There were 223 teachers who rated the lectures: 72% were from North America or Western Europe, 40% had taught epidemiology, and 14% reported that the speed of access was slow. Odds ratio of above-average rating among those who reported that the speed of access was fast relative to those who reported that the speed of access was slow was 4.25 (2.03-8.91; P = 0.001). The odds ratios were similar and significant after taking into account several other factors, including the variation of rating across lectures, region, and experiences in teaching epidemiology. The results indicate that the perception of the quality of Web-based lectures is related to the speed of access to a web page. The speed of access may be as important, if not more important, as the content itself. This suggests that, to share educational materials on the Web globally for teachers, one must consider not only the content, but also how people at local sites gain access to the Internet. 相似文献
115.
Pulmonary embolism after hip or knee replacement: postoperative changes on pulmonary scintigrams in asymptomatic patients 总被引:1,自引:0,他引:1
Foley M; Maslack MM; Rothman RH; Casey MP; Lugano EM; Parry CE; Balderston RA; Booth RE Jr 《Radiology》1989,172(2):481-485
Serial pulmonary imaging has proved to be effective in the evaluation of patients undergoing total joint arthroplasty. A clinical dilemma arises in asymptomatic patients whose postoperative pulmonary images differ from the preoperative images. The authors prospectively evaluated 403 patients with serial imaging to determine the significance of changed postoperative images in asymptomatic patients undergoing total hip or knee arthroplasty. Twenty-two (5.5%) patients had significant changes on postoperative images. Seventeen were asymptomatic; all but one underwent pulmonary angiography. Documented pulmonary emboli were demonstrated in 100% of patients whose postoperative images changed to indicate a high probability of pulmonary embolism, 71% whose images changed to a moderate probability, and 0% whose images changed to indeterminate probability. Overall, pulmonary emboli occurred in 76% of all asymptomatic patients with significantly change postoperative images. Asymptomatic pulmonary embolism is a significant occurrence after total hip or knee repair, and a changed lung scan with appropriate clinical evaluation is an accurate indicator of pulmonary emboli in asymptomatic postarthroplasty patients. 相似文献
116.
Of 179 patients with stage B or C adenocarcinoma of the prostate, 106 underwent iodine-125 seed-implant therapy (I-125 SI) and 73 received external-beam radiation therapy (EB). A retrospective analysis determined disease-free survival rate, local tumor control, and complication rate for each treatment group. The 5-year disease-free survival rates for SI-treated patients were 75% for stage B and 30% for stage C groups. Corresponding rates for EB-treated patients were 75% and 40%, respectively. The rate of local tumor control for stage B patients was 85% for SI-treated and 88% for EB-treated patients. The corresponding rates for stage C tumors were 75% for SI-treated and 92% for EB-treated patients. The rate of long-term complications in each group was approximately 10%. For stage B cancer of the prostate, I-125 SI treatment is an acceptable alternative to EB therapy; our data are inconclusive regarding stage C treatment, but EB therapy is preferred. 相似文献
117.
Meticulous monitoring and control of the treatment offers patients injured in accidents the best conditions for healing and leads to cost reductions in terms of compensation for injury, vocational aid measures and pensions. The accident and emergency hospital maintained by the employers’ liability insurance association in Hamburg is currently conducting a project entitled “Hand Injuries” in collaboration with the professional association for health services and welfare’s Hamburg regional office, which is aimed at realizing and documenting this aim. 相似文献
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119.
Fourteen institutions performed 1,830 computed tomographic (CT) cerebral blood flow (CBF) examinations with 32% inhaled stable xenon. Respiratory rate delay greater than 10 seconds occurred in 3.6% of patients, with 83% of the delays lasting 10-15 seconds. There was no incident of prolonged respiratory difficulty. Headache (0.4%), seizures (0.2%), nausea and vomiting (0.2%), and change in neurologic status (0.1%) were uncommon, and there were no transient ischemic attacks. The CT CBF method with 32% inhaled stable xenon is thus associated with an acceptably low incidence of adverse reactions. 相似文献
120.
A comparative investigation of FK506 and cyclosporin A in murine corneal transplantation 总被引:3,自引:0,他引:3
A. Reis Thomas Reinhard Rainer Sundmacher Stefan Braunstein Erhard Godehardt 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》1998,236(10):785-789
· Background: Acute rejection is the cause of over 50% of transplant opacifications in some immunological high-risk groups.
More potent immunomodulating substances must be found in order to allow extended or individualised therapeutic options for
combating rejection. · Methods: Rats of the inbred strains Brown Norway and Lewis were used as donors and recipients, respectively.
FK506 (Prograf) was administered intraperitoneally for 14 days in a dosage of 0.3 mg/kg bw, and cyclosporin A (CSA; Sandimmun)
was administered, likewise for 14 days, in an intramuscular dosage of 10 mg/kg bw. The transplants were examined every 3rd
day by slit-lamp microscopy. Every transplant was subjected to histological or immunohistological evaluation. · Results: The
average transplant survival period in the allogeneic strain combination was 7.9 days (SEM=1.1). Therapy with FK506 led to
a statistically significant prolongation of transplant survival to 17.1 days (SEM=1.5, P<0.05). Therapy with CSA delayed transplant rejection to 21 days (SEM=0.0, P<0.05). No statistically significant difference was found between the two therapeutic regimens. There were no significant
histomorphologic differences in rejected grafts in the FK506- and CSA-treated animals. · Conclusions: In this study we have
shown that FK506 is able to delay corneal allograft rejection at a much lower dosage than CSA without a higher incidence of
side effects related to toxicity or overimmunosuppression.
Received: 8 September 1997 Revised version received: 16 December 1997 Accepted: 13 January 1998 相似文献