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51.
对管碟法测定Nisin效价的条件进行了研究,考察了几个参数的影响,得出了Nisin测定的最佳条件:90mm培养皿中培养基加量为15mL,Na2HPO4·12H2O质量浓度1g/dL,菌悬液浓度109CFU/mL,琼脂质量浓度1g/dL,培养基pH值7.0,牛津杯中样品加液量100μL.在此条件下,Nisin效价在5~100IU/mL,其对数值与抑菌圈直径有较好的线性关系. 相似文献
52.
为了探讨腰神经通道狭窄的病因,我们对224例腰椎间盘突出及腰椎管狭窄症患者进行了腰神经通道探查手术,结果发现其病因以腰部组织变性为主。除外伤及反复慢性腰部损伤引起腰部病变外,活动少,或很少进行腰部锻炼,体形肥胖也是引起腰神经通道狭窄日趋加重的致病因素。在治疗时强调不只满足于切除突出的椎间盘,应沿神经通道探查,清除一切卡压神经根的病变组织才能获得较好的治疗效果。我们随访197例,平均随访3a,优良率935%。 相似文献
53.
Shigenori Inao Yoshiharu Takemitsu H. Edward Conrad 《Journal of orthopaedic science》1996,1(6):369-375
Monolayer cultures of 12-day chick embryo chondrocytes from the regions of dividing (zone 1), elongated (zone 2), and hypertrophied
(zone 3) chondrocytes in the tibial cpiphyseal growth plate were analyzed for their capacity to synthesize types II, IX, X,
and XI collagens. Synthesis of types II and IX collagens was markedly elevated in the zone 2 culture, while type X collagen
synthesis was maximal in zone 3. Type XI collagen was synthesized at low rates in all cultures, with some elevation of its
rate in zones 2 and 3. In terms of mol percent of total collagen synthesis, types II and IX collagens decreased from zone
1 to zone 3, while type X collagen increased progressively. Thus, the composition of the extracellular collagens produced
by the different zones changed markedly during chondrocyte differentiation. In addition, type X collagen was released exclusively
into the culture medium, whereas type XI collagen was retained in the extracellular cell-associated matrix. In contrast, types
II and IX collagens were found in both the culture medium and the cell matrix pools. Although types II and IX collagens showed
similar changes during differentiation, the synthetic molar ratios of these two collagens varied from 3 to 18 in different
cultures, suggesting that the synthesis of these two products is not tightly coupled in these cells. 相似文献
54.
加压滑动鹅头钉治疗股骨转子间骨折的临床与实验研究 总被引:27,自引:0,他引:27
探讨加压滑动鹅头钉在治疗股骨转子间骨折中的作用。临床应用45例。男34例,女11例。平均年龄61岁。稳定型13例,不稳定型32例。经临床应用和生物力学实验测定,结果表明:(1)对不稳定型转子间骨折,恢复小转子区内后侧皮质骨的连续性在骨折的稳定中具有重要作用。(2)内后侧骨折块解剖复位,加压螺丝钉固定或大转子骨折端加压螺丝钉固定能显著增强加压滑动鹅头钉的固定作用,明显提高不稳定型转子间骨折的术后稳定性。(3)该装置设计合理,性能坚固,对转子间骨折具有很强的固定作用,能有效地达到早期下床和避免长期卧床的目的,是目前临床最理想的内固定装置。 相似文献
55.
Claude Clément MD Roberto Ruiz MD Bogdan Costa-Foru MD Hubert Nicaise MD 《Annals of vascular surgery》1990,4(3):305-308
Extrinsic compression of the renal artery due to a fibromuscular band originating from the diaphragm was encountered in a 26-year-old patient who had systemic hypertension associated with stenosis and kinking of one of her renal arteries. After surgical decompression, the renal artery assumed a normal expansion with disappearance of hypertension. Six other cases of extrinsic compression of the renal artery have been found in the literature. Surgical treatment is mandatory in all cases because the mechanism that causes the lesion makes percutaneous transluminal angioplasty illusory. 相似文献
56.
Allen D. Roses Margaret A. Pericak-Vance Ann M. Saunders Donald Schmechel Dmitry Goldgaber Warren Strittmatter 《Epilepsia》1994,35(S1):S20-S28
Summary: Strategies used in molecular genetics have changed modern neurology. The gene or genes responsible for several major neurologic diseases have now been identified using "reverse" or positional genetics. Unexpected new genetic mechanisms have been discovered in human neurologic diseases, including (a) identical mutations of the prion protein gene in Creutzfeldt-Jakob disease and fatal familial insomnia with the phenotypic expression directed by an accompanying polymorphism; (b) stable duplications of chromosome 17 in Charcot-Marie-Tooth disease (type 1 A) that involve many genes, only one of which appears to cause neuropathy; and (c) highly variable, dynamic mutations in myotonic dystrophy, fragile X syndrome, and Kennedy's syndrome that modulate variable expressivity in multiple tissues. There is growing recognition that neurologic diseases are often complex genetic diseases with multifactorial rather than simple modes of inheritance. For example, genetic association/linkage strategies have interacted with biochemistry and immunopathology studies to produce new insights into the disease mechanism of late-onset Alzheimer's disease. The role of apolipoprotein E in late-onset Alzheimer's disease is an example of how new analytical techniques of genetic disease can be applied to dissect multiple genes. Similar research strategies are suggested for the study of epilepsy as a complex disease. 相似文献
57.
Deformation due to growth disturbance after epiphyseal fractures around the knee may involve more than the primarily injured
epiphysis, as spontaneous corrective growth of the opposite epiphyseal plate can take place in an attempt to maintain overall
alignment of the leg. As a result, there will be an inclination in the knee joint line if corrective osteotomy is only performed
for the primary angulation. We report two cases of this complex deformity in which corrective osteotomies of both the distal
femur and the proximal tibia were performed, resulting in correct alignment of the overall leg axis and knee joint axis.
Received: 25 May 1996 Accepted: 20 November 1996 相似文献
58.
应力松弛接骨板对骨几何形态和力学性能影响的实验观察 总被引:2,自引:0,他引:2
《中华医学杂志》1995,(7)
作者采用粘弹性材料制成垫圈置于接骨板螺孔与螺丝钉之间,构成应力松弛接骨板系统。实验证实,有垫与无垫接骨板在固定早期对模拟骨的应力遮挡作用相同,固定8周后垫圈出现明显变形和破坏,使有垫接骨板的应力遮挡率从第10周起明显低于无垫接骨板。有垫接骨板固定的胫骨骨质疏松明显轻于无垫组,固定20周后,有垫组的胫骨髓腔径明显小于无垫组,骨皮质厚度和胫骨抗弯强度均明显大于无垫组(P<0.05~0.01)。说明应力松弛接骨板系统早期具有与坚强接骨板相同的固定作用,后期其应力遮挡效应可逐渐减小,避免严重的骨质疏松和骨力学性能下降。 相似文献
59.
G. J. Breur M. D. Lapierre K. Kazmierczak K. M. Stechuchak G. P. McCabe 《Calcified tissue international》1997,61(5):418-425
In this study, we tested the hypotheses that (a) both the domain volume (volume of the cell and the matrix it has formed)
and matrix volume of juxtametaphyseal hypertrophic chondrocytes in the growth plate is tightly controlled, and that (b) the
domain volume of juxtametaphyseal hypertrophic chondrocytes is a strong determinant of the rate of bone length growth. We
analyzed the rate of bone length growth (oxytetracycline labeling techniques) and nine stereologic and kinetic parameters
related to the juxtametaphyseal chondrocytic domain in the proximal and distal radial and tibial growth plates of 21- and
35-day-old rats. The domain volume increased with increasing growth rates, independent of the location of the growth plate
and the age of the animal. Within age groups, the matrix volume per cell increased with increasing growth rates, but an identical
growth plate had the same matrix volume per cell in 21- and 35-day-old rats. The most suitable regression model (R
2= 0.992) to describe the rate of bone length growth included the mean volume of juxtametaphyseal hypertrophic chondrocytes
and the mean rate of cell loss/cell proliferation. This relationship was independent of the location of the growth plate and
the age of the animal. The data suggest that the domain volume of juxtametaphyseal hypertrophic chondrocytes, as well as the
matrix volume produced per cell, may be tightly regulated. In addition, the volume of juxtametaphyseal hypertrophic chondrocytes
and the rate of cell loss/rate of cell proliferation may play the most important role in the determination of the rate of
bone length growth.
Received: 2 December 1996 / Accepted: 24 March 1997 相似文献
60.
Summary Plain radiography, myelography and post-myelographic CT-scan are described and related to clinical findings in a prospective
study of 153 consecutive patients with myelographic signs of spinal cord compression. The majority of the metastatic tumours
arise in the vertebral body or the pedicles. In 80% of the patients with total blockage to the contrast medium on myelography
the post-myelographic-CT showed passage of the contrast medium. Ambulatory function at time of diagnosis was correlated to
the degree and the localization of the epidural block. In 64 patients who underwent a second myelography, the post-treatment
findings of sensory function were correlated to radiological regression. 相似文献