PC机辅助三维表面覆盖法诊断颞骨茎突骨折的临床价值

目的:探讨PC机辅助三维表面覆盖法诊断颞骨茎突骨折的临床价值。方法:对45例颌面及颅底外伤的患者进行多层螺旋CT薄层扫描后,经PC机辅助三维表面覆盖法成像。结果:45例患者中发现颞骨茎突骨折9例,其中双侧骨折2例,单侧骨折7例,均合并有不同程度的颌面部及颅底骨折。结论:PC机辅助三维表面覆盖法可直观地了解颞骨茎突骨折在三维立体空间的实际大小、形态、位置及周围结构的解剖关系,对诊断和治疗有重要的指导作用,同时具有实用、方便、经济诸多优点,值得在颞骨茎突、颌面、骨与关节疾病诊断应用领域推广。     

Effects of the Addition of Autologous Seminal Plasma to Highly Concentrated Stallion Semen After 48 Hours of Cooled Storage

Insemination with chilled transported semen has become distinctly important in the horse-breeding industry. To ensure cell survival during cooled storage, semen is diluted with an appropriate extender and the concentration of seminal plasma (SP) is reduced. Nevertheless, SP plays an important immunomodulatory role in the female genital tract and supports sperm fertility. The aim of the present study was to evaluate the effect of the addition of autologous SP after cooled storage to highly concentrated stallion semen. Therefore, SP was removed by simple centrifugation of extended semen, aspiration of the supernatant, and resuspension of the sperm pellet with semen extender. Motion characteristics were evaluated after cooled storage for 48 hours at concentrations of 333 × 10⁶ sperm/mL in comparison with stored samples at concentration of 25 × 10⁶ sperm/mL (control). The highly concentrated semen samples were diluted with an extender containing 0%, 5%, 20%, and 80% SP directly before motility analysis. Dilution of the cooled semen with a fresh semen extender without SP (0%) increased kinematic parameters (curvilinear velocity [VCL] 137.3 vs. 151.8; straight-line velocity [VSL] 49.0 vs. 57.5; average path velocity [VAP] 69.5 vs. 79.4 μm/second; amplitude of lateral head [ALH] 3.1 vs. 3.3 μm; beat cross frequency [BCF] 31.6 vs. 33.5 Hz; P < .05) but not total motility (51% vs. 43%) and progressive motility (46% vs. 36%) compared with controls. The addition of SP after storage for 48 hours decreased sperm total motility and progressive motility regardless of SP concentration: 5 (38% and 34%), 20 (37% and 33%), and 80% SP (27% and 22%; P < .05). In contrast, kinematic parameters were enhanced by extenders containing 5% and 20% SP (VCL: 148.0 and 155.6; VSL: 59.2 and 60.9; VAP: 78.7 and 81.9; BCF: 33.4 and 35.7; ALH: 3.4 and 3.4; P < .05). However, using an extender containing 80% SP was detrimental to kinematic parameters (VCL: 151.2; VSL: 52.2; VAP: 76.9; BCF: 34.8; P < .05) except for ALH, which increased (3.5; P < .05). In conclusion, cooled storage at concentrations of 333 × 10⁶ sperm/mL did not affect sperm motility. The addition of a fresh extender or an extender containing small concentrations of SP to highly concentrated ejaculated sperm increased kinematic values after storage; however, increasing concentrations of SP decreased sperm motility.     

Evolution of burrow systems after the accidental introduction of a new earthworm species into a Swiss pre-alpine meadow

 The unintentional introduction of a new earthworm species (Aporrectodea nocturna) into a Swiss pre-alpine meadow resulted in a great increase in earthworm density in the newly colonized area (386 m^–2) compared with the density observed in the natural area (273 m^–2) where an earthworm community was already present. To investigate the impact of this introduction on the burrow systems, eight soil cores (length 25 cm, diameter 16 cm) were taken (four in the colonized area and four in the natural area) and analysed with computer-assisted X-ray tomography. The resulting images were processed to obtain the 3D-skeleton reconstructions of the earthworm burrow systems. Due to high variability in these burrow systems, only slight differences were observed between the two areas. The total burrow length and the mean burrow lengths tended to be greater in the colonized area. Moreover, the distribution of pore numbers with depth showed different patterns with a maximum for depths between 10 cm and 15 cm in the colonized area and a maximum for depths between 20 cm and 25 cm in the natural area. These differences may have been related to: (1) the particular behaviour of A. nocturna, which was observed to cast at the surface in this site, and (2) the predominance of juvenile earthworms around the colonization front. These differences were sufficient to create significant effects on the continuity of the burrow systems (assessed by the number of different pathways between virtual horizontal planes) for the two areas. The colonized area was characterized by a greater pore continuity, which could have resulted in enhanced transfer properties. Received: 2 July 1999     

Nucleomorphometric analysis of feline basal cell carcinomas

Twenty-four feline spontaneous basal cell carcinomas (BCCs) were analyzed by computerized nuclear morphometry. The study included 15 non-recurrent and 9 recurrent tumours. In each case, the nuclei of at least 100 neoplastic cells were measured, and the mean nuclear area (MNA), mean nuclear perimeter (MNP) and mean nuclear diameter (MND) were calculated. The analysis of data of the non-recurrent BCCs and the recurrent tumours revealed statistically significant differences between those groups (p<0.001) as well as between infiltrative and clear types of BCCs (p<0.05). The results indicate that nuclear morphometry is able to predict recurrent tumour growth and helps to differentiate histological subtypes of BCCs in cats.     

Changing soil and surface conditions during rainfall: Single rainstorm/subsequent rainstorms

During rainstorms, physical properties of the soil surface change significantly. As a result of surface sealing, variations in infiltration rate, water content, water suction, bulk density and surface roughness can be observed and quantified. Dynamic processes taking place on the soil surface were investigated in laboratory and field experiments on a typical loess-derived soil in Germany. This study focused on the effects of continuous and subsequent rainfall treatments. Furthermore, all laboratory experiments were carried out in two different initial moisture regimes. In the laboratory experiments, a capillary rainfall simulator was used. Water suction was measured with microtensiometers 2 cm below the sealed surface in a 30 s time interval. The water content was determined with TDR probes in a variable time step, depending on the movement of the infiltration front. Compared to the continuous rainfall treatment, the decline of infiltration rate was much steeper in the subsequent rainfall events. After 2 h of continuous rainfall, a ‘drying effect' could be observed underneath the surface sealing at a depth of 2 cm. This was not the case in the intermittent treatment. Saturated conditions 10 cm below the surface sealing were reached in none of the treatments. The variation of bulk density within the first centimeter of the soil was determined via computed tomography and also with two simple methods using micro soil cores [Fohrer, N., 1995. Auswirkungen von Bodenfeuchte, Bodenart und Oberflächenbeschaffenheit auf Prozesse der Flächenerosion durch Wasser. PhD Thesis, Technical University Berlin, Bodenökologie und Bodengenese, No. 19, 183 pp.] and immersion as described by Roth [Roth, C.H., 1997. Bulk density of surface crusts: depth functions and relationships to texture. Catena 29 (3–4) 223–237.]. Under continuous rainfall conditions, the initially dry plots showed a higher compaction than the initially moist treatments. In the case of subsequent rainstorms, it was shown that the bulk density–depth function is not constant with time. The alteration of surface roughness was measured using a laser relief meter. The levelling effect of the intermittent rainfall regime proved to be much stronger in comparison to the continuous event.