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1.
Painful calcinosis appeared at the wrist of an eight-year-old girl with lead poisoning. Careful history revealed that calcification occurred at the site of previous extravasation of calcium disodium edetate (EDTA) used in chelation therapy. Light microscopic, ultrastructural, electron activation, and X-ray diffraction studies demonstrated apatites with some suggestion of an admixture of octacalcium phosphate.  相似文献   
2.
During a three-year period, 95 adults were treated by lower-extremity amputations for peripheral vascular insufficiency. A multidisciplinary team for presurgical evaluation determined all to be potentially independent walkers with a prosthesis. Patients were graded for level of independent walking before amputation and again at a minimum two-year follow-up examination using a seven-level functional grading system. Seventy-six of 90 patients (84%) ambulated within one functional level of their preamputation status. This return to preamputation level of function was maintained whether comparing preamputation functional level or surgical amputation level. Prosthetic use increased and the use of walking aids decreased with increased functional ambulation levels, but did not correlate with surgical levels. Peripheral vascular insufficiency patients can maintain walking independence. Multidisciplinary presurgical evaluation helps selection of the amputation level and correct prosthetic limb fitting.  相似文献   
3.
We analyzed clinical and radiographic long-term results in 96 patients (106 hips) with Perthes' disease 35 years after nonoperative treatment. 19 hips in 17 patients had early radiographic signs indicating atypically severe course of the disease and poor prognosis. None of them was radiographically good at skeletal maturity; 2 cases were fair and 17 poor. At the final follow-up 12 hips had radiographic arthrosis.  相似文献   
4.
Although infra-inguinal autogenous vein graft stenoses may be treated by balloon dilatation (PTA) or surgical revision, the optimal approach is undefined. Over the last 7 years 24 PTA procedures were performed on 37 vein graft stenoses in 19 grafts. Graft stenoses were diagnosed from 2 to 72 (mean = 17.3) months after implantation. PTA was successfully completed in 23 (96%) of the 24 procedures including 18 (95%) of the primary, and 5 (100%) of the secondary procedures. Recurrent vein graft stenosis or graft thrombosis developed in 12 (67%) grafts from 3 to 47 (mean = 12.5) months after primary PTA. Long-term patency after primary PTA was 69% at 6, 29% at 12, and 22% at 36 months; secondary patency was 81% at 6, 45% at 12, and 27% at 36 months. During the same period vein graft stenosis in 7 fem-pop and 2 fem-tib grafts were surgically revised with an initial success rate of 100%, and 2 (22%) complications. Four (44%) of these grafts occluded from 1-17 (mean 6.2) months after repair, yielding a primary 5-year patency of 62%. Although vein graft stenosis may be safely, effectively, and repeatedly treated with PTA, long-term durability appears to be superior after surgical revision.  相似文献   
5.
We report the results of the treatment of multiple ruptures of extensor tendons to the fingers at wrist level in the rheumatoid patient by free tendon grafts. Twenty-three patients averaged 65 degrees of active motion at the metacarpophalangeal joints when seen at an average follow-up of 43 months.  相似文献   
6.
The effect of volleyball playing on the knee extensor mechanism   总被引:3,自引:0,他引:3  
The knee extensor mechanism was examined in 32 male competitive volleyball players (Group V) and in a control group of 49 young adult males (Group C) to evaluate the effects of previous jumping activity on the knee extensor mechanism. Several variables were recorded by means of a structured questionnaire, and by clinical and radiographic examination. The amount of physical activity from the age of 7 years onward was significantly greater in Group V than in Group C. The incidence of anterior knee pain during the year preceding the examination was higher in Group V (31%) than in Group C (6%; P less than 0.01). The most common reason for anterior knee pain in Group V was so-called "jumper's knee." No significant difference between the groups was found in the incidence of clinical symptoms and signs of patellar chondromalacia. There were radiologically detectable soft tissue calcifications at the upper or lower pole of the patella or anterior to the patella in 38% of the subjects in Group V, but no such calcifications were seen in Group C (P less than 0.001). However, persistent symptoms did not correlate with the calcifications. Group V subjects had a slight but significant trend to patella alta when compared to Group C (P less than 0.05) according to the Blackburne and Peel index.  相似文献   
7.
Delayed-type hypersensitivity responses of inbred mice during the course of lethal and chronic infections with strains of Rickettsia tsutsugamushi were evaluated by using the influx of radiolabeled cells into antigen-injected ears. Congenic strains of C3H mice, which previously have been shown to be resistant (C3H/RV) or sensitive (C3H/HeDub) to lethal intraperitoneal infection with the Gilliam strain of rickettsiae, both expressed delayed-type hypersensitivity early in the course of infection (5 to 7 days). The sensitive C3H/HeDub mice, however, exhibited a marked decline in reactivity just before death. In contrast, reactivity of C3H/RV mice remained high through day 9 and declined slowly through day 15 after infection. Similar results were obtained when BALB/c mice were infected with either the Karp or the Gilliam strain of rickettsiae, which produce a lethal or nonlethal infection, respectively, in this strain of mice. Rechallenge of C3H/RV mice elicited a rapid increase in reactivity, suggesting a secondary memory response. To analyze delayed-type hypersensitivity during chronic infection, C3H/HeDub mice were immunized by subcutaneous infection with the Gilliam strain of R. tsutsugamushi, and both delayed-type hypersensitivity reactivity and resistance to intraperitoneal challenge were examined. Delayed-type hypersensitivity reactivity developed slowly and peaked at 21 days postimmunization, which correlated with resistance to intraperitoneal challenge. Delayed-type hypersensitivity reactivity declined thereafter, but resistance to intraperitoneal challenge remained through 28 days postimmunization. Delayed-type hypersensitivity reactivity increased after secondary challenge at 28 days, again suggesting antigen memory generated by primary immunization. Transfer of delayed-type hypersensitivity reactivity was accomplished by using immune thymus-derived splenic lymphocytes isolated with nylon-wool columns. Abrogation of the ability of immune spleen cells to transfer delayed-type hypersensitivity reactivity after treatment with anti-Thy 1.2 alloantiserum and complement further supported the view that delayed-type hypersensitivity responses to scrub typhus rickettsiae were mediated by thymus-derived lymphocytes.  相似文献   
8.
The genetic basis for natural resistance to lethal infection with Rickettsia akari was studied in over 25 inbred strains, inbred hybrids, and outbred stocks of mice. Inbred mice infected intraperitoneally with the Kaplan strain of R. akari demonstrated three levels of response, susceptible (C3H/HeJ), intermediate (A/HeJ, A/J, A/WySn, BALB/cDub, BALB/cJ, and SJL/J), and resistant (AKR/J, AL/N, BALB/cAnN, BALB/cNCr1BR, C3H/HeN, C57BL/6J, C57L/J, CBA/J, DBA/2J, and SWR/J). No correlation was evident between the six H-2 haplo-types tested and susceptibility to Kaplan infection. Four outbred mouse stocks, Dub: (ICR), Wrc:(ICR), Caw:(CF1), and Mai:(S) were all resistant. The F1 inbred hybrids of resistant X resistant (AKD2F1/J), resistant X intermediate (CB6F1/U), intermediate X intermediate (CAF1/J), and resistant X susceptible (C3D2F1/J) parents were all resistant. The F2 and parental backcross generations of C3H/HeJ and DBA/2J hybrids yielded ratios of resistant to susceptible mice that suggested resistance was under multigeneic control. Susceptible mice (C3H/HeJ) were capable of mounting an immune response, since prior infection with the avirulent Hartford strain of R. akari rendered them resistant to subsequent lethal challenge with the Kaplan strains.  相似文献   
9.
Human bornavirus encephalitis is a severe and often fatal infection caused by variegated squirrel bornavirus 1 (VSBV-1) and Borna disease virus 1 (BoDV-1). We conducted a prospective study of bornavirus etiology of encephalitis cases in Germany during 2018–2020 by using a serologic testing scheme applied along proposed graded case definitions for VSBV-1, BoDV-1, and unspecified bornavirus encephalitis. Of 103 encephalitis cases of unknown etiology, 4 bornavirus infections were detected serologically. One chronic case was caused by VSBV-1 after occupational-related contact of a person with exotic squirrels, and 3 acute cases were caused by BoDV-1 in virus-endemic areas. All 4 case-patients died. Bornavirus etiology could be confirmed by molecular methods. Serologic testing for these cases was virus specific, discriminatory, and a practical diagnostic option for living patients if no brain tissue samples are available. This testing should be guided by clinical and epidemiologic suspicions, such as residence in virus-endemic areas and animal exposure.  相似文献   
10.
Summary The pharmacokinetics of pyridostigmine was evaluated after intravenous injection in two healthy male volunteers and after oral administration to five subjects. Plasma concentrations of pyridostigmine were determined after ion pair extraction from plasma and analysis by gas chromatography — mass spectrometry with chemical ionization, using d6-pyridostigmine as internal standard. Degradation of pyridostigmine in vitro was compensated for by use of the deuterated internal standard and by rapid cooling and separation of plasma after blood sampling. After intravenous administration of pyridostigmine 2.5 mg the plasma elimination half-life was 1.52 h, the volume of distribution was 1.43 l/kg and the plasma clearance 0.65 l/kg × h. The pharmacokinetic constants were very similar after oral administration of pyridostigmine 120 mg; the elimination half-life was 1.78±0.24 h, the volume of distribution 1.64±0.29 l/kg and the plasma clearance was 0.66±0.22 l/kg × h. The bioavailability was calculated to be 7.6±2.4%. When pyridostigmine was taken together with food, the time to reach the peak plasma concentration was prolonged from 1.7 to 3.2 h. Bioavailability, however, was not influenced by concomitant food intake. Steady-state plasma concentrations of pyridostigmine were measured in myasthenic patients on their ordinary dose schedule of cholinesterase inhibitor drugs. More than a seven-fold difference in steady-state plasma concentration was found between patients taking approximately the same daily dose of pyridostigmine.  相似文献   
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