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91.
The problem of appraising qualitative research   总被引:3,自引:0,他引:3       下载免费PDF全文
  相似文献   
92.
93.
A case of congenital self-healing reticulohistiocytosis in an otherwise healthy newborn boy is presented. Histological, immunohistochemical, and ultrastructural findings are described and the nosologic position of this entity is discussed.  相似文献   
94.
One hundred nine percutaneous catheterizations of synthetic vascular grafts in 89 patients who had angiographic procedures were reviewed to determine the risk of major complications. Ninety-six of the catheterizations were inserted into the inguinal portion of aortofemoral grafts. There were no instances of hematoma, graft infection, aneurysm formation, suture line disruption, or embolic events distal to the puncture site. One local thrombus developed within a vascular graft that was corrected by a simple thrombectomy performed with a surgical catheter. One puncture site required 2 hours of compression to maintain hemostasis. Because of the extremely low risk of complications from catheterization of synthetic vascular grafts, it is the preferred route for angiographic procedures when the native femoral arterial route is unavailable.  相似文献   
95.
CYP51 fulfills an essential requirement for all cells, by catalyzing three sequential mono-oxidations within the cholesterol biosynthesis cascade. Inhibition of fungal CYP51 is used as a therapy for treating fungal infections, whereas inhibition of human CYP51 has been considered as a pharmacological approach to treat dyslipidemia and some forms of cancer. To predict the interaction of inhibitors with the active site of human CYP51, a three-dimensional quantitative structure-activity relationship model was constructed. This pharmacophore model of the common structural features of CYP51 inhibitors was built using the program Catalyst from multiple inhibitors (n = 26) of recombinant human CYP51-mediated lanosterol 14alpha-demethylation. The pharmacophore, which consisted of one hydrophobe, one hydrogen bond acceptor, and two ring aromatic features, demonstrated a high correlation between observed and predicted IC(50) values (r = 0.92). Validation of this pharmacophore was performed by predicting the IC(50) of a test set of commercially available (n = 19) and CP-320626-related (n = 48) CYP51 inhibitors. Using predictions below 10 microM as a cutoff indicative of active inhibitors, 16 of 19 commercially available inhibitors (84%) and 38 of 48 CP-320626-related inhibitors (79.2%) were predicted correctly. To better understand how inhibitors fit into the enzyme, potent CYP51 inhibitors were used to build a Cerius(2) receptor surface model representing the volume of the active site. This study has demonstrated the potential for ligand-based computational pharmacophore modeling of human CYP51 and enables a high-throughput screening system for drug discovery and data base mining.  相似文献   
96.
OBJECTIVE: To estimate the association of passenger seating position with the risk of death for passengers in traffic crashes. Design, setting, PARTICIPANTS: Matched cohort analysis of data from the National Highway Traffic Safety Administration Fatality Analysis Reporting System regarding 56 644 passengers in 23 308 passenger cars, light trucks, vans, and sport utility vehicles that crashed during 1990-2001. MAIN OUTCOME MEASURE: The adjusted risk ratio (aRR) for death of a rear seat passenger compared with a front seat passenger within 30 days of a crash. RESULTS: The aRR for all passengers in the rear seat in a crash was 0.79 (95% CI 0.77 to 0.82). This estimate varied by age, restraint use, and the presence of a front passenger airbag (p<0.001). For restrained passengers in cars with a front passenger airbag, the aRR was 0.62 (95% CI 0.48 to 0.81) for children 0-12 years, 0.96 (95% CI 0.88 to 1.06) for passengers 13-29 years, 1.03 (95% CI 0.93 to 1.15) for passengers 30-59 years, and 1.06 (95% CI 0.90 to 1.26) for passengers 60 years or older. The rear seat was associated with more protection in cars without front airbags and more protection for unrestrained passengers compared with restrained passengers. CONCLUSIONS: Previous studies have reported that the rear seat was safer for persons of all ages; thus seating a young child in the rear has often meant that older children and adults had to assume an increased risk of death by sitting in the front. These results suggest that when front passenger airbags are present and passengers are restrained, putting adults in front and children in back enhances child safety without sacrificing adult safety.  相似文献   
97.
Smith Kevin C.  BA  BSc  MD  FACP  FRCPC    Melnychuk Michael  BSc  DDS 《Dermatologic surgery》2005,31(S4):1635-1637
Background. Injection of filler substances into the lips is painful, and many patients also find the injection of local or regional anesthesia into the lips painful.
Objective. To develop a highly effective and painless form of anesthesia to facilitate injection of filler substances into the lips.
Methods. Five percent lidocaine cream was applied simultaneously to the skin, vermilion, and mucosa of the lips (with the use of a barrier to keep the cream in contact with the mucosa and out of the rest of the mouth) for 20 to 30 minutes.
Results. Profound anesthesia of the lips was reliably produced, with no complications.
Conclusions. This "anesthetic cream block" is easier to perform and better tolerated than injectable anesthetics. Use of this technique is likely to expand the range of physicians who perform filler injections on the lips and will probably also expand the range of patients who wish to have filler injections done on their lips and who (because they had little or no discomfort) are willing to return for additional filler injections in the future.  相似文献   
98.
Two patients with angiolymphoid hyperplasia with eosinophilia isolated to the orbit had eyelid swelling, a superior orbital mass, and histories of intermittent obstructive airway disease. One patient later developed a transient peripheral blood eosinophilia as high as 36%. One lesion recurred 38 months postoperatively and responded to systemic corticosteroid therapy.  相似文献   
99.
Repeated administration of the antimanic drug lithium (4 mEq/kg/day for 2, 4 or 6 days, i.p.) to rats produced a progressive decline and eventual depletion of dynorphin-A (1-8) (DYN) concentration whereas Met5-enkephalin (ENK) was only marginally decreased in the neurointermediate lobe of the pituitary (NIL). Administration of a neuroleptic haloperidol neither affected ENK and DYN levels nor influenced lithium-induced changes. The study reveals that lithium produces a preferential perturbation in the dynorphin system relative to the enkephalin system. These results taken together with other evidence, indicate that dynorphin is possibly coreleased with vasopressin following lithium administration and provide a pharmacological support to the previously described colocalization and corelease of these endogenous peptides in the NIL.  相似文献   
100.
The ameloblastoma is a tumor arising predominantly in the mandible from odontogenic epithelium, and is locally invasive. It is rarely malignant; but even when benign, it causes gross local destruction and expansion of tissue. Growth is persistent, and recurrence may occur more than a decade after presumed total resection. Surgical resection should include a reasonable margin of healthy tissue whenever possible. Late patient presentation due to a paucity of symptoms, and insiduous tumor growth patterns render complete removal of the ameloblastoma difficult. Follow-up examinations should span a prolonged period, exceeding 10-15 years.  相似文献   
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