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101.
102.
103.
W L Donegan  P Harris 《Cancer》1976,38(4):1479-1483
Fifteen patients were treated with intra-arterial fluorouracil, methotrexate, and bleomycin in combination for palliation of advanced cancer of the head and neck. In all cases irradiation or irradiation plus surgical resection had previously failed to control the tumor. Tumor regression occured in 87% of the cases (13/15), and was complete in three (20%). Regressions lasted for up to 13 months. In four instances tumor regression permitted radical resection. The response rate achieved with this drug combination was greater than that observed earlier using each drug individually. Intra-arterial chemotherapy provides useful palliation for advanced head and neck cancer and the results can be improved with drug combinations.  相似文献   
104.
The ability of histamine to inhibit the overall contractile ('twitch') response of the isolated vas deferens of the mouse to electrical field stimulation (64 V pulse, 1 ms pulse width, frequency 0.2 Hz) was studied in nine inbred mouse strains. The strains were also characterized in terms of the potency of the histamine H2-receptor antagonist cimetidine in its inhibition of histamine-mediated effects. An apparently bimodal inter-strain variation (8-10 fold) in both characteristics was encountered, with three strains (SWR, A2G and C57BL/10ScSn) relatively sensitive (S) to both agonist and antagonist actions, and six (C3H, A, C57/BL6, DBA/2, Balb/C and 129/Sv) relatively insensitive (IS). These strain differences were independent of extracellular calcium concentration in the range 1.25-5 mM, and also independent of the frequency of tissue stimulation over the range 0.2-6.4 Hz. Representative S (SWR and A2G) and IS (DBA/2 and C3H) mouse vasa were also characterized in terms of their sensitivity to the agonist actions of dimaprit and the antagonist actions of tiotidine. In the S strain tissues, dimaprit produced 50% inhibition of the twitch response at 4.6-1.8 microM (mean +/- s.d.) and was able to elicit complete inhibition of the twitch response at concentrations greater than 100 microM, whereas 48.7 +/- 11.9 microM dimaprit was required to produce 50% inhibition of the twitch response in tissues from IS mice. In addition, the agonist actions of dimaprit were incomplete in the latter tissues, the drug eliciting no more than 75% inhibition of the twitch response at concentrations in the range 300-1000 microM.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
105.
Purpose This study focuses on the curvature and inclination of the lingual surfaces of the maxillary anterior teeth from the transition point on the cingulum to the incisal edge. Materials and Methods On 32 sets of mounted casts, 768 measurements were made of the curvature of the lingual surfaces utilizing radius gauges. The inclination of the lingual surface relative to the occlusal plane was recorded. The relationship of the incisal edge of the mandibular teeth to the transition point on the cingulum of the maxillary teeth was determined. Centric occlusion contact was noted on each tooth. Results Significant differences were found between the measured areas of any one tooth and between the types of teeth. The average radius ranged from 20.5 mm on the mesial ridge of the canine to 5.3 mm in the fossa of the central. The average inclination of the lingual surfaces was 46%. In centric occlusion, 97% of the canines and 59% of the centrals and laterals were in contact with the opposing teeth. These contacts occurred 2.8 mm incisal to the transition point. The centrals contacted two opposing teeth (45%), and canines contacted one opposing tooth (53%). Conclusions The function and curvature of the incisor teeth vary considerably from those of the canines. Overcontouring the lingual surfaces of the maxillary incisors to gain contact is not normal and may be detrimental.  相似文献   
106.
Reconstruction of soft tissue defects in the lower leg and foot after traumatic injury is a challenging problem owing to lack of locally reliable flaps. The traditional options for wound coverage often do not provide feasible or adequate treatment for many of these wounds. The lack of skin laxity in the lower leg and foot often make local flaps unavailable. Split-thickness skin grafts will not be robust enough. Free tissue flaps have a litany of potential complications and guaranteed comorbidities. The present case reinforces that appropriately selected patients with significant open bony and soft tissue trauma to the foot and ankle can be treated with a reverse sural artery fasciocutaneous flap. The reverse sural artery flap allows for full-thickness skin coverage with its own blood supply, maximizing the healing potential and should be considered a viable first option for soft tissue coverage.  相似文献   
107.
BACKGROUND: Numerous studies have linked dementia to the subsequent deterioration of oral health. Few investigators, however, have examined oral disease as a potential risk factor in the development of dementia. The authors conducted a study to investigate a potential association between a history of oral disease and the development of dementia. METHODS: Longitudinal dental records supplemented data collected from 10 annual cognitive assessments of 144 Milwaukee participants in the Nun Study, a longitudinal study of aging and Alzheimer disease, who were 75 to 98 years old. Neuropathologic findings at autopsy were available for 118 participants who died. RESULTS: A low number of teeth increased the risk of higher prevalence and incidence of dementia. CONCLUSION: Participants with the fewest teeth had the highest risk of prevalence and incidence of dementia. CLINICAL IMPLICATIONS: Edentulism or very few (one to nine) teeth may be predictors of dementia late in life.  相似文献   
108.
Unusual kinetics of white cell clearance in transfused mice   总被引:1,自引:0,他引:1  
BACKGROUND: Donor white cells (WBCs) in blood transfusions are responsible for complications in recipients, including alloimmunization, graft-versus-host disease (GVHD), and virus transmission and reactivation. The recent use of sequence-specific polymerase chain reaction assays to monitor the kinetics of clearance of donor WBCs in transfused humans and dogs found transient recirculation of donor lymphocytes on Days 3 to 5 after transfusion; this presumably reflected an abortive GVHD reaction to major histocompatibility complex-incompatible recipient cells, after which donor WBCs were cleared to undetectable levels. STUDY DESIGN AND METHODS: This study sought to develop a murine model to further characterize the kinetics and major histocompatibility complex restriction of donor WBC clearance. A sensitive murine Y chromosome- specific polymerase chain reaction assay was developed and applied to serial blood samples collected after transfusions of allogeneic blood to naive inbred, primed inbred, and outbred mice, as well as after transfusions of gamma-radiated blood to naive inbred mice. RESULTS: In inbred mice, both naive and primed to the allogeneic blood donor, transfused WBCs were not cleared to undetectable levels for more than 1 month after transfusion. Transfused outbred mice also showed prolonged donor WBC survival, although at lower levels than inbred mice. There was no evidence of GVHD in either inbred or outbred mice, and gamma radiation had no significant impact on donor WBC persistence. CONCLUSION: These results contrast with the rapid clearance of donor WBCs observed in humans and dogs. The immunologic basis for this discrepancy remains unclear. Caution should be exercised in any extrapolation to humans of conclusions drawn from results in transfused mice.  相似文献   
109.

Introduction

Injuries to the anterior or posterior pelvic ring rarely occur in isolation. Disruption to the anterior pelvic ring, indicated by a fracture of the superior or inferior pubic ramus, or injury to the pubic symphysis, may be indicative of additional pelvic ring disruption. The purpose of this retrospective study was to determine whether displaced inferior pubic ramus fractures warrant a more detailed investigation of the posterior ring in an effort to predict unstable posterior pelvic ring injuries.

Materials and methods

All patients with a displaced inferior ramus fracture on AP pelvic radiograph were identified at a single level I trauma center over a 5-year period. Complete pelvic radiographs and computed tomography scans were then evaluated for additional pelvic ring injuries. The data were analyzed using the chi-square test to determine the association between inferior ramus fractures and posterior pelvic ring injury.

Results

Sixty-three of the 93 patients with a fracture of the inferior ramus (68 %) were found to have a posterior ring injury; 60 % of these injuries were unstable. Patients with concurrent superior ramus fractures were more likely to have a posterior ring injury (p < 0.001) and an unstable pelvis (p = 0.018). Of those with a displaced unilateral inferior ramus fracture, parasymphyseal involvement was associated with higher incidence of posterior ring injury (p = 0.047) and pelvic instability (p = 0.028).

Conclusion

The anterior pelvic ring can be used to help identify unstable injuries to the posterior pelvis. Patients with displaced inferior pubic ramus fractures warrant a detailed examination of their posterior ring to identify additional injuries and instability.  相似文献   
110.
Trends in the number of tests for HIV-1 antibody at a London sexually transmitted diseases clinic showed substantial changes between September 1985 and June 1988. From an average of 100 tests per month between September 1985 and August 1986, the average increased to 365 tests per month for September 1986 to August 1987. This levelled off at 243 tests per month between September 1987 and June 1988. The average number of positive tests per month between September 1985 and June 1988 remained constant, though the number of seropositive tests in females increased. Male and female populations displayed similar temporal patterns. The greatest increase was seen in the tests generated by heterosexual males and females with no other risk factors. This group generated 42% of the 8012 tests performed during the study period. The Clinic's catchment area predominantly included London and surrounding areas and temporal patterns were similar for residents from each of the Thames Regions. The temporal patterns observed coincided with periods of increased media attention on HIV infection/AIDS and involved campaigns by the popular press, television, Department of Health Education Authority. The increase in tests during the time of maximum media exposure, the subsequent plateau at a level substantially higher compared with the period preceding the media campaigns and the large increase in heterosexual males and females tested, all suggest that the campaigns have contributed to increasing awareness of HIV infection/AIDS as a major contemporary public health problem.  相似文献   
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