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71.
Objective. The aim of this article is to review the current knowledge of Doppler ultrasound in canine pregnancy. A brief introduction of Doppler principles and their applications in human obstetrics is also included. Methods. A review of the peer‐reviewed published literature was conducted of the articles pertaining to the use of Doppler ultrasound in canine pregnancy, general Doppler principles, and Doppler applications in human obstetrics. Results. In bitches, Doppler ultrasound has been used to assess ovarian, uterine, umbilical, fetal aorta, common carotid artery, and fetal caudal vena cava blood flow during normal gestation. Most of these vessels increase their blood flow during normal pregnancy. The resistive index and systolic/diastolic ratio of the uterine arteries have been recently described in an experimental pharmacologically induced model of abnormal canine gestation. Both indices progressively increase up to abortion, probably because of progesterone deprivation. Moreover, resistive index abnormalities have been found in canine cases of spontaneous abnormal gestations as described in human medicine. Conclusions. Doppler ultrasound is a useful method for assessing development of the placental and fetal circulation during normal and abnormal canine pregnancy. Further studies are still necessary to widely use this technique in clinical practice.  相似文献   
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Background and purpose:

Vascular tolerance to nitroglycerin (GTN) may be caused by impaired GTN bioactivation due to inactivation of mitochondrial aldehyde dehydrogenase (ALDH2). As relaxation to GTN is reduced but still sensitive to ALDH2 inhibitors in ascorbate deficiency, we compared the contribution of ALDH2 inactivation to GTN hyposensitivity in ascorbate deficiency and classical in vivo nitrate tolerance.

Experimental approach:

Guinea pigs were fed standard or ascorbate-free diet for 2 weeks. Reversibility was tested by feeding ascorbate-deficient animals standard diet for 1 week. Nitrate tolerance was induced by subcutaneous injection of 50 mg·kg−1 GTN 4 times daily for 3 days. Ascorbate levels were determined in plasma, blood vessels, heart and liver. GTN-induced relaxation was measured as isometric tension of aortic rings; vascular GTN biotransformation was assayed as formation of 1,2-and 1,3-glyceryl dinitrate (GDN).

Key results:

Two weeks of ascorbate deprivation had no effect on relaxation to nitric oxide but reduced the potency of GTN ∼10-fold in a fully reversible manner. GTN-induced relaxation was similarly reduced in nitrate tolerance but not further attenuated by ALDH inhibitors. Nitrate tolerance reduced ascorbate plasma levels without affecting ascorbate in blood vessels, liver and heart. GTN denitration was significantly diminished in nitrate-tolerant and ascorbate-deficient rings. However, while the ∼10-fold preferential 1,2-GDN formation, indicative for active ALDH2, had been retained in ascorbate deficiency, selectivity was largely lost in nitrate tolerance.

Conclusions and implications:

These results indicate that nitrate tolerance is associated with ALDH2 inactivation, whereas ascorbate deficiency possibly results in down-regulation of ALDH2 expression.  相似文献   
74.
原发性脾囊肿是一种罕见的疾病,目前尚缺乏对该疾病的理想治疗方法的相关研究.大多数原发性脾囊肿是上皮性囊肿.近几年,腹腔镜脾脏外科手术普及率不断提高.该研究报告了关于经腹腔镜保脾手术治疗脾囊肿的相关经验.1996年至2006年间,作者治疗了11例有症状的非寄生虫性脾脏巨大囊肿病人.病人均诉左上腹涨满症状,触诊可扪及腹部包块.术前腹部超声及CT均已明确诊断.病人接受经腹腔镜脾脏囊肿部分切除术或脾脏囊肿开窗减压术.结果发现,7例病人为脾脏间皮囊肿,2例为脾脏表皮样囊肿,2例为脾脏假性囊肿,没有发现囊肿癌变.手术操作时间为62~85 min,无中转开腹.  相似文献   
75.
Ragni  MV; Bontempo  FA; Myers  DJ; Kiss  JE; Oral  A 《Blood》1990,75(6):1267-1272
Clinical bleeding tendency and tests of immune function were studied prospectively in 11 human immunodeficiency virus (HIV)-infected hemophiliacs with immune thrombocytopenic purpura (ITP) and a platelet count less than 50,000/microL. These 11 patients represented 13% of a well-characterized cohort of 87 HIV + hemophiliacs. ITP developed a mean 3.5 years after seroconversion, mean platelet count at presentation was 36,000/microL (range 15,000 to 49,000/microL), and the mean age at seroconversion was 37.1 years. Nine patients (82%) suffered bleeding complications, including four with intracranial hemorrhage, which was fatal in three. At the onset of ITP, five had AIDS and six were asymptomatic. Mean T4 lymphocyte count at onset of ITP was 126 +/- 32/microL (range 5 to 267/microL). Sustained treatment responses occurred with intravenous gammaglobulin (2 of 2), one of whom spontaneously remitted, and with zidovudine (1 of 2), but not with steroids (0 of 6) or danazol (0 of 3). In conclusion, 13% of a cohort of HIV + hemophiliacs has developed ITP with platelets less than 50,000/microL, a significant proportion of whom (82%) have experienced bleeding complications. It is recommended that treatment for ITP in HIV + hemophiliacs be instituted once the platelet count falls below 50,000/microL in order to avoid serious hemorrhagic sequelae.  相似文献   
76.

Background

Hospitals have a critically important role in the management of mass causality incidents (MCI), yet there is little information to assist emergency planners. A significantly limiting factor of a hospital''s capability to treat those affected is its surgical capacity. We therefore intended to provide data about the duration and predictors of life saving operations.

Methods

The data of 20,815 predominantly blunt trauma patients recorded in the Trauma Registry of the German-Trauma-Society was retrospectively analyzed to calculate the duration of life-saving operations as well as their predictors. Inclusion criteria were an ISS ≥ 16 and the performance of relevant ICPM-coded procedures within 6 h of admission.

Results

From 1,228 patients fulfilling the inclusion criteria 1,793 operations could be identified as life-saving operations. Acute injuries to the abdomen accounted for 54.1% followed by head injuries (26.3%), pelvic injuries (11.5%), thoracic injuries (5.0%) and major amputations (3.1%). The mean cut to suture time was 130 min (IQR 65-165 min). Logistic regression revealed 8 variables associated with an emergency operation: AIS of abdomen ≥ 3 (OR 4,00), ISS ≥ 35 (OR 2,94), hemoglobin level ≤ 8 mg/dL (OR 1,40), pulse rate on hospital admission < 40 or > 120/min (OR 1,39), blood pressure on hospital admission < 90 mmHg (OR 1,35), prehospital infusion volume ≥ 2000 ml (OR 1,34), GCS ≤ 8 (OR 1,32) and anisocoria (OR 1,28) on-scene.

Conclusions

The mean operation time of 130 min calculated for emergency life-saving surgical operations provides a realistic guideline for the prospective treatment capacity which can be estimated and projected into an actual incident admission capacity. Knowledge of predictive factors for life-saving emergency operations helps to identify those patients that need most urgent operative treatment in case of blunt MCI.  相似文献   
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