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591.
592.

Objective

The purpose of this case study is to describe the clinical presentation of a patient with a chief complaint of low back and leg pain with no prior diagnosis of lung cancer.

Clinical Features

A 48-year-old man with a history of back pain presented to a chiropractic office with a complaint of low back and left leg pain.

Intervention and Outcome

Abnormal examination and radiographic findings were discovered. The patient was immediately referred to the pulmonologist for co-management. Through the use of advanced imaging and biopsy, stage 4 lung cancer was diagnosed.

Conclusion

Low back pain recurrence in an established patient should constitute a reevaluation of the problem. The cause cannot be assumed to be musculoskeletal in origin even though this may have been the case with the initial complaint. Metastatic disease should be considered with any type of recurrent low back pain.  相似文献   
593.

Objective

The purpose of this study was to determine whether healthy adult volunteers report symptoms following exposure to low-speed frontal crashes at low velocities.

Methods

Nineteen medically screened, healthy, informed, and willing volunteers (17 men, 2 women; mean age, 37 years) were exposed to low-speed frontal crashes. All volunteers were seated in the rear seat position of the bullet vehicle. Closing velocities ranged from 4.1 to 8.3 mph (mean, 6.7 mph). For the bullet vehicle, the delta V ranged from 1.4 to 3.9 mph with a mean of 2.8 mph.

Results

Eighty-eight percent of volunteers attributed symptoms of discomfort to their crash exposure. All reported symptoms were transient, and none required medical treatment. The mean duration was 1 day.

Conclusions

Even at relatively low speeds, there is no lower threshold below which it can be reasonably assumed that healthy and prepared volunteer rear seat passengers will not sustain some level of minor injury in a frontal collision. Although the reported mean delta V for injured persons in real-world frontal crashes has been reported to be as high as 8.1 mph, this does not offer any insight into the minimum threshold for such injuries among all at-risk vehicle occupants.  相似文献   
594.

Background and purpose:

The volatile anaesthetic isoflurane protects the heart from ischaemia and reperfusion (I/R) injury when applied at the onset of reperfusion [anaesthetic postconditioning (APoC)]. However, the mechanism of APoC-mediated protection is unknown. In this study, we examined the effect of APoC on mitochondrial bioenergetics, mitochondrial matrix pH (pHm) and cytosolic pH (pHi), and intracellular Ca2+.

Experimental approach:

Cardiac mitochondria from Wistar rats were isolated after in vivo I/R with or without APoC (1.4%-vol isoflurane, 1 minimum alveolar concentration), and mitochondrial permeability transition pore (mPTP) opening, mitochondrial membrane potential (ΔΨm), and oxygen consumption were assessed. In isolated cardiomyocytes and isolated mitochondria I/R injury was produced in vitro, with or without APoC (0.5 mM isoflurane). Intracellular Ca2+, pHm, pHi and ΔΨm were monitored with SNARF-1, TMRE and fluo-4, respectively. Myocyte survival was assessed when APoC was induced at pH 7.4 and 7.8. In isolated mitochondria oxygen consumption and ATP synthesis were measured.

Key results:

In vivo APoC protected against mPTP opening, slowed mitochondrial respiration and depolarized mitochondria. APoC decreased the number of hypercontracted cardiomyocytes at pH 7.4, but not at pH 7.8. APoC attenuated intracellular Ca2+ accumulation, maintained lower pHm, and preserved ΔΨm during reoxygenation. Isoflurane did not affect the regulation of cytosolic pH. In mitochondria, APoC preserved ATP production rate and respiration.

Conclusions and implications:

At reperfusion, APoC inhibited mitochondrial respiration, depolarized mitochondria and acidified pHm. These events may lead to inhibition of mPTP opening and, consequently, to preserved ΔΨm and ATP synthesis. This reduces intracellular Ca2+ overload and cell death.This article is commented on by Moncada, pp. 217–219 of this issue. To view this commentary visit http://dx.doi.org/10.1111/j.1476-5381.2010.00706.x and to view related papers in this issue by Puerta et al. and Kurz et al. visit http://dx.doi.org/10.1111/j.1476-5381.2010.00663.x and http://dx.doi.org/10.1111/j.1476-5381.2010.00656.x  相似文献   
595.
While there is much information and discussion on pregnancy failure after assisted reproductive technologies, less emphasis is placed on the failure to collect oocytes after apparently successful ovarian stimulation. This retrospective survey reviewed 4973 treatment cycles in order to obtain information about the likelihood of this event. Overall 42 women (43 treatment cycles) failed to have oocytes collected [0.86% of treatments started and 0.92% of women given human chorionic gonadotrophin (HCG)]. However, in only six cases was this failure unexpected (0.1%) with no obvious potential clinical reason (i.e. all six cases had: HCG administered; more than two follicles >15 mm in diameter; oestradiol values >2000 pmol/l; <38 years old; normal body mass index). Indifference concerning uncommon events is fraught with peril, as although rare, the particular outcome may be devastating to the individual, both economically and psychologically. Eighteen of the 42 women did not return for on-going treatment suggesting increased contact by clinic staff may be required when oocyte retrieval is not achieved. These data suggest that the failure to collect oocytes after apparently successful ovarian stimulation is rare and random. The information has proved useful in allaying the fears of couples contemplating assisted reproductive technologies.   相似文献   
596.
在临床分子生物学诊断中,聚合酶链反应-单链构象多态性(PCR-SSCP)技术是一种有效的检测基因变异的方法[1,2],我们使用自动电泳和分离系统Phastsy-stem进行电泳分离,结合银染进行DNA分析,特别适用于迅速检出含有变异序列的外显子。1材...  相似文献   
597.
598.
599.
Assessment of living renal donors with spiral CT   总被引:4,自引:0,他引:4  
  相似文献   
600.
Angiographic evaluation of chronic pulmonary embolism   总被引:1,自引:0,他引:1  
  相似文献   
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