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91.
广州市1996—2005年管网末梢水卫生状况及对策分析 总被引:1,自引:0,他引:1
目的了解广州市管网末梢水的水质情况,为随时监测全市生活饮用水水质的动态变化提供信息并提出改进措施。方法对广州市1996—2005年管网末梢水水质监测资料进行统计,按照GB5749—85《生活饮用水卫生标准》和卫生部《生活饮用水卫生规范》(2001年)进行分析评价。结果共监测606份水样,合格155份,合格率为25.58%。不合格的项目主要有锰、游离余氯、细菌总数、色度、铁和耗氧量。在广州市疾病预防控制中心检测的项目中,锰的合格率仅为59.57%,游离余氯的合格率为76.73%,细菌总数的合格率为85.81%,色度的合格率为88.12%,铁的合格率为88.94%,耗氧量的合格率为96.37%。结论广州市管网末梢水的锰、游离余氯、细菌总数和铁等项目合格率较低,今后应加强饮水的氯化消毒、对管网的定期检修和冲洗、减少二次供水水箱的使用和设立管网水水质自动监测系统。 相似文献
92.
目的 检测肺鳞状细胞癌中死亡相关蛋白激酶 (DAP K)mRNA表达及细胞凋亡 ,探讨DAP K与细胞凋亡的关系及其在肺鳞状细胞癌发生、发展中的作用。方法 用原位分子杂交法检测 6 0例肺鳞状细胞癌、9例癌旁肺组织DAP KmRNA表达 ;用原位末端标记TUNEL法检测相应组织中细胞凋亡 ,计算凋亡指数 (AI)。结果 肺鳞状细胞癌的DAP KmRNA阳性表达率为 4 6 7% ,癌旁肺组织为 6 7 7% ,其阳性率高于肿瘤组织 (P <0 0 1 )。在肺鳞状细胞癌中 ,高分化癌DAP KmRNA阳性率为 70 % ,低分化癌为 2 3 3% ,高分化癌的DAP KmRNA阳性率高于低分化癌 (P <0 0 1 )。肺鳞状细胞癌的细胞AI为(0 6 72 8± 0 4 2 6 1 ) % ,癌旁肺组织中支气管肺泡上皮细胞AI为 (1 0 2 89± 0 2 4 33) % ,癌旁肺组织的AI高于肿瘤组织 (P<0 0 1 )。在肺鳞状细胞癌中 ,高分化癌的AI为 (0 5 82 3± 0 1 92 2 ) % ,低分化癌为 (0 4 4 6 0± 0 1 92 5 ) % ,高分化癌的AI高于低分化癌 (P <0 0 1 )。DAP KmRNA呈阳性表达的肺癌 ,其AI为 (0 5 31 7± 0 2 0 97) % ;DAP KmRNA呈阴性者 ,其AI为 (0 4 872± 0 1 91 8) % ,两组间差异有显著性 (P <0 0 5 )。在连续切片上 ,DAP KmRNA阳性细胞的分布区域与凋亡阳性细胞的分布相似。DAP KmRNA呈阳性表达 相似文献
93.
J. J. Visser J. E. Hoogkamer M. F. Bobbert P. A. Huijing 《European journal of applied physiology》1990,61(5-6):453-460
Summary Lengths of muscle tendon complexes of the quadriceps femoris muscle and some of its heads, biceps femoris and gastrocnemius muscles, were measured for six limbs of human cadavers as a function of knee and hip-joint angles. Length-angle curves were fitted using second degree polynomials. Using these polynomials the relationships between knee and hip-joint angles and moment arms were calculated. The effect of changing the hip angle on the biceps femoris muscle length is much larger than that of changing the knee angle. For the rectus femoris muscle the reverse was found. The moment arm of the biceps femoris muscle was found to remain constant throughout the whole range of knee flexion as was the case for the medial part of the vastus medialis muscle. Changes in the length of the lateral part of the vastus medialis muscle as well as the medial part of the vastus lateralis muscle are very similar to those of vastus intermedius muscle to which they are adjacent, while those changes in the length of the medial part of the vastus medialis muscle and the lateral part of the vastus lateralis muscle, which are similar to each other, differ substantially from those of the vastus intermedius muscle. Application of the results to jumping showed that bi-articular rectus femoris and biceps femoris muscles, which are antagonists, both contract eccentrically early in the push off phase and concentrically in last part of this phase. 相似文献
94.
目的 探讨后路经皮内窥镜下颈椎椎间盘切除术的安全范围。 方法 选取20具成人颈椎标本,分别测量C3/C4至C6/C7各节段左右两侧V点与硬脊膜外侧距离、V点与椎动脉水平及垂直距离、小关节面宽度,并进行统计学比较。 结果 V点与硬脊膜外侧距离为:左(1.31±0.32)~(2.46±0.60) mm,右(1.29±0.35)~(2.75±0.45) mm,各节段间差别有统计学意义,同一水平左右差别无统计学意义;V点与椎动脉水平距离为:左(2.17±0.42)~(5.10±0.93) mm,右(1.99±0.39)~(5.00±0.71) mm,各节段间差别有统计学意义,同一水平左右差别无统计学意义;V点与椎动脉垂直距离为:左(11.05±1.06)~(13.47±1.12)mm,右(11.33±1.20)~(13.61±1.01)mm,同一水平左右侧差别有统计学意义,节段间比较C3/C4与C4 /C5无明显差异,其余节段间差别均有统计学意义;小关节面宽度为:左(10.79±0.93)~(12.66±0.88) mm,右(10.86±0.68)~(12.54±0.70)mm。 结论 后路经皮内窥镜下颈椎椎间盘切除术的安全范围宜控制在距V点内侧C3/C4至C6/C7各水平1.20~2.00 mm;磨除范围距V点外侧C3/C4至C6/C7各水平超过2.00~5.00 mm时可能到达椎动脉体表投影处,因此需注意此时的手术进入深度宜控制在:C3/C4~C6/C7各节段距V点11.00~14.00 mm。 相似文献
95.
Satoshi Muraki Masahiro Yamasaki Yoshito Ehara Kunio Kikuchi Kunihiro Seki 《European journal of applied physiology》1996,74(5):481-483
The purpose of the present study was to examine the effect of maximal arm exercise on the skin blood circulation of the paralyzed
lower limbs in persons with spinal cord injury (PSCI). Eight male PSCI with complete lesions located between T3 and L1 performed
graded maximal arm-cranking exercise (MACE) to exhaustion. The skin blood flux at the thigh (SBFT) and that at the calf (SBFC)
were monitored using laser-Doppler flowmeter at rest and for 15 s immediately after the MACE. The subject's mean peak oxygen
uptake and peak heart rate was 1.41 ± 0.22 l · min–1 and 171.6 ± 19.2 beats · min–1, respectively. No PSCI showed any increase in either SBFT or SBFC after the MACE, when compared with the values at rest.
These results suggest that the blood circulation of the skin in the paralyzed lower limbs in PSCI is unaffected by the MACE.
Accepted: 12 September 1996 相似文献
96.
97.
We have studied the haemodynamic effects of the application of the medical anti-shock trouser (MAST) in 10 healthy subjects in the semi-upright position in order to simulate mild hypovolaemia. Left ventricular end diastolic dimension (EDD) was measured by M-mode echocardiography and cardiac output (CO) by the Doppler ultrasound technique. Forearm blood flow (FBF) was measured by plethysmography and blood pressure (BP) by the standard cuff technique. Systematic increases in MAST pressure of up to 80 mm Hg were applied. EDD increased to a maximum of 9.3% (p0.01) which was associated with a maximum increase in CO of 31.7% (p0.05). FBF increased by a maximum of 54.2% (p0.001) whilst BP increased by a maximum of 12% (p0.001). These results demonstrate that the application of the MAST is an effective means of transferring blood to the central circulation by compression of the capacitance vessels resulting in significant increases in cardiac output and tissue perfusion. At high pressures there was evidence of compression of resistance vessels, which may be useful in reducing blood loss. The ease and rapidity with which his suit can be applied suggests that it may be useful in the short term treatment of hypovolaemia. 相似文献
98.
目的 比较周围神经端侧缝合与神经移植的效果。方法 选用体重 2 0 0~ 30 0gWistar大白鼠 ,左侧后肢腓总神经与胫神经端侧缝合 ,右侧腓总神经采用神经移植修复。结果 3个月后运动神经传导速度分别为2 9.6 8± 5 .34m/s、 30 .87± 6 .0m/s(P >0 .0 5 ) ,潜伏期 2 .1± 0 .1ms ,2 .0± 0 .1ms(P >0 .0 5 ) ,波幅 12 .5± 0 .6mV、13.9± 0 .5mV(P >0 .0 5 ) ,组织切片中 ,两组均可见大量神经纤维和髓鞘 ,有髓神经纤维计数分别为 75 7.2± 2 2 .31、775± 2 1.87(P >0 .0 5 )。结论 ①正常神经发出侧芽能通过端侧缝合口长入远端神经 ,使变性神经再神经化 ;②周围神经端侧缝合能取得与神经移植相近的结果。 相似文献
99.
Surgeons are privileged to offer treatments that often cure disease. Optimizing comfort for those who cannot be cured is also a core part of every clinician's duty: surveys repeatedly tell us that when death is approaching, people value quality of life above length of survival. Recognizing when someone is dying can be difficult. Tools exist to help; it is worth noting that emergency presentation with life-threatening symptoms can be a marker of poor prognosis. Clear, effective communication is crucial: understanding the patient's perspective and expectations is vital before attempting to offer information that allows future care planning. Judicious use of surgery combined with careful prescribing will optimize comfort, allowing the patient to live as well as possible for as long as possible. Anticipatory prescribing includes opioid, anti-emetic, anti-secretory and sedative medication. Attention should also be given to care of the bereaved. Generalists should understand when to refer to specialist palliative care and remember that reflecting on care when someone has died can be beneficial for professional wellbeing. 相似文献
100.