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61.
C. Vyvyan Howard Luis M. Cruz-Orive Hiroshi Yaegashi 《Acta neurologica Scandinavica》1992,85(S137):14-19
The recently developed method of total vertical projections is illustrated to estimate the total dendritic length of a human Substantia Nigra neuron. Next, the length of the different orders of dendritic branches, and the mean segment length for each order - commonly regarded as important parameters in neuron physiology - are also estimated. Finally, it is shown how to estimate the mean dendritic length in a population of neurons from vertical slices of arbitrary and unknown thickness. Being unbiased and highly efficient, the proposed methods offer interesting alternatives to current procedures used for the metric analysis of neuron arborizations. 相似文献
62.
A case is reported in which entrapped polymethylmethacrylate following traumatic dislocation of a total hip replacement prevented complete reduction. A combined arthroscopic and fluoroscopic technique was used to remove the entrapped polymethylmethacrylate. Manipulation of the total hip prosthesis was done after removal of polymethylmethacrylate to minimize mechanical abrasion. This technique allows direct visual assessment of the articulating surfaces as well as the mechanical stability of the prosthesis. The morbidity related to the procedure is minimal and a short rehabilitation period is the major advantage. 相似文献
63.
N G Forouhi D Merrick E Goyder B A Ferguson J Abbas K Lachowycz S H Wild 《Diabetic medicine》2006,23(2):189-197
AIMS: To estimate the total prevalence of diabetes mellitus (diagnosed and undiagnosed) at national, regional and local level in England to support health-care planning and delivery. METHODS: An epidemiological model was constructed by applying age-sex-ethnic-specific reference prevalence rates from epidemiological studies to resident populations (2001 census) of England at national, regional, and local authority/Primary Care Trust levels. RESULTS: Estimated prevalence of total diabetes for all persons in England was 4.41% in 2001, equating to 2 168 000 persons. Type 2 diabetes was estimated to affect 2 002 000 persons (92.3%) and Type 1 diabetes 166 000 persons (7.7%). Diabetes prevalence was estimated to be higher in women (5.17%) than men (3.61%). People from ethnic minority groups had higher crude prevalence than White Europeans (4.29, 5.69, 6.63 and 2.13% among White Europeans, Black African/Caribbeans, South Asians and 'other' groups, respectively). Prevalence increased sharply with age (0.33, 3.37 and 13.92%, respectively, in those aged 0-29, 30-59 and 60+ years). The model allows use of user-defined population denominator estimates to derive numbers and prevalence of people with diabetes for a given local population group, such as at ward or general practice level. CONCLUSIONS: Self-reported diabetes prevalence estimates from community surveys underestimate the true burden of diabetes. The model can be used to derive the expected total prevalence of diabetes in health areas that lack reliable data to facilitate the implementation of the National Service Framework for diabetes. It will also allow estimates of future diabetes prevalence to be derived, and can potentially be used for prevalence estimates in all of the UK. 相似文献
64.
65.
Yoshinori Uji Arthur Karmen Hiroaki Okabe Keishi Hata Masakazu Miura Kazuyuki Ozaki Mitsuo Minamizaki Tetsushi Shibata Seiichi Inayama 《Journal of clinical laboratory analysis》1994,8(5):267-272
An automated measurement of total and free hydroxyproline in serum or urine is presented that uses flow injection analysis. After exclusion of nonspecific substances, hydroxyproline was oxidized by chloramine- T and L-cysteine with Ehrlich's reagent. The linearity obtained was from 3.8μmole/ L to 1.22 mmole/L with good precision (CV <3%). Comparison of the proposed method with HPLC yielded r = 0.939 as the correlation coefficient. Reference intervals of free and total hydroxyproline are 1.4–9.7 μmole/L, 3.8–27.2 μmole/L for serum, and 10.0–72.5 μmole/L, 25.2–303.6 μmole/L for urine, respectively. Serum free and total hydroxyproline levels in renal osteodystrophy patients on maintenance hemodialysis (N = 71) were significantly higher than in controls (P<0.0001). This method is superior to the use of HPLC with regard to stability of the color reaction. The measurement of serum free and total hydroxyproline is a useful marker for therapeutic observation of renal osteodystrophy patients. © 1994 Wiley-Liss, Inc. 相似文献
66.
Edward McNulty Joshua Cohen Tony Chou Kendrick Shunk 《Catheterization and cardiovascular interventions》2006,67(1):46-48
We present two patients with angulated, proximal left circumflex lesions, one a chronic total occlusion and one an acute subtotal occlusion. In both cases, use of the deflectable tip Venture Catheter (Velocimed, Minneapolis, MN) facilitated guide wire passage and successful percutaneous coronary intervention (PCI) after prior attempts at guide wire passage with standard wires were unsuccessful. 相似文献
67.
Day-to-day variations in serum iron, serum iron binding capacity, serum ferritin and erythrocyte protoporphyrin were determined on 2 successive days in 48 patients with anaemia. The correlation coefficients between the paired determinations were 0.86, 0.89, 0.95 and 0.95, and the day-to-day coefficients of variation (in per cent) were 33, 11, 12 and 13 for serum iron, serum iron binding capacity, erythrocyte protoporphyrin and serum ferritin, respectively. Thus, in patients with anaemia, day-to-day variations in serum iron, serum iron binding capacity, erythrocyte protoporphyrin and serum ferritin are at least as high as in healthy controls. The results indicate important limitations in the use, particularly, of serum iron in the clinical investigation of anaemia. 相似文献
68.
Serum levels of free insulin-like growth factor (IGF)-I were measured by
immunoradiometric assay (IRMA) in fasting sera of 137 normal boys and 120 normal girls
aged from 8 to 15 yr to study relationships between free IGF-I levels and ages, total
IGF-I, IGF binding protein (IGFBP)-1, IGFBP-3, and acid-labile subunit (ALS) levels. In
both sexes, serum free IGF-I levels and the ratios of free IGF-I to total IGF-I were
significantly higher in the pubertal age groups than in the prepubertal age groups. Serum
levels of free IGF-I showed a significant positive correlation with those of total IGF-I,
IGFBP-3 and ALS, while they showed a significant negative correlation with those of
IGFBP-1. These observations suggest that increase in serum free IGF-I levels during
puberty is caused by a dramatic increase in total IGF-I, rather than IGFBP-3, and a
decrease in IGFBP-1. Also, high free IGF-I levels may play an important role in pubertal
growth spurt. 相似文献
69.
70.
低位前外侧入路微创全髋置换术 总被引:6,自引:0,他引:6
目的:评价低位前外侧入路微创全髋关节置换术的可行性和早期临床效果.方法:17位患者18例髋关节进行前外侧入路微创全髋关节置换术,仰卧位,自大转子上2 cm为顶向前下切口,纵行切开髂胫束和臀中肌前部着点,由髋关节囊前方分离至髋臼前外缘.不脱位,经股骨颈截骨和取头,处理髋臼植入假体.患髋内收外旋股骨颈基底脱出切口外,股骨扩髓后植入假体.结果:手术切口平均长(10.5±2.1)cm.切口长短与体重正相关,髋臼病理改变和翻修者更长.手术时间平均为(101.7±14.6)min,术中出血量110~600ml,平均(302.2±77.3)ml;双侧髋关节置换1例.术后2~5 d患髋均可负重行走.随访7~22个月,Harris评分平均:术前44;术后6个月85.假体位置理想.无并发症.结论:经低位的前外侧入路行微创全髋关节置换术,需要特殊的髋关节拉钩和牵开技术.有创伤小、不损伤臀上神经、假体位置理想、术中可以处理较复杂病理改变、准确测量两侧下肢体长度、术后外展肌有力、早期康复等优点. 相似文献