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991.
The central nervous system plays a key role in the regulation of cardiovascular function, and alterations in the central neural
mechanisms that control blood pressure may underlie the vast majority of cases of primary hypertension. The well-studied baroreceptor
reflex powerfully regulates arterial pressure, though its involvement in the pathogenesis of chronic hypertension is likely
to be only of minor importance. Supraspinal maintenance of sympathetic vasomotor outflow appears to emanate from neurons in
the rostral ventrolateral medulla, and the tonic drive exerted on sympathetic vasomotor activity by the rostral ventrolateral
medulla appears to be increased in several animal models of hypertension. In particular, the excitation of the rostral ventrolateral
medulla by excitatory amino acid neurotransmitters and by stimulation of AT1 angiotensin receptors appears to be increased in experimental hypertension. The current data support the view that neurogenic
hypertension is mediated by increased excitatory drive of rostral ventrolateral medulla sympathoexcitatory neurons. 相似文献
992.
Cooper LA 《Journal of general internal medicine》2004,19(9):985-986
993.
Intracerebral hemorrhage (ICH) remains the least treatable form of stroke. Despite ongoing attempts to find effective interventions based on the physiopathologic understanding of this disease, evidence-based medical therapies for ICH are limited to recommendations on blood pressure (BP) reduction, intracranial pressure monitoring, osmotherapy with adequate fluid resuscitation, fever and glycemic control, and seizure prophylaxis. Although the value of surgical treatment remains in doubt because of the negative results of the International Surgical Trial in Intracerebral Haemorrhage (STICH), a subgroup analysis of this study suggested better outcomes among patients with superficial hematomas who underwent surgical evacuation, supporting the ongoing STICH-II trial. Other approaches currently under study include ultra-early hemostatic therapy and BP reduction, thrombolytic therapy for intraventricular hemorrhage, and minimally invasive surgical approaches. 相似文献
994.
Seth J. Worley Douglas C. Gohn Robert W. Pulliam 《Journal of interventional cardiac electrophysiology》2008,23(2):135-137
Introduction Venoplasty allows the addition or replacement of leads despite subtotal or total subclavian occlusion.
Methods The threshold of the LV pacing lead implanted for biventricular pacing over a period of 18 months increased to greater than
5 V. A pre implant venogram revealed total subclavian occlusion. Venous access was maintained by extraction of the 4 F LV
lead over a wire. Subsequently the sheath would not advance despite 6mm balloon inflation to 30 atm with no residual waist.
A wire was placed beside the balloon and the balloon was reinflated.
Results The subclavian obstruction was eliminated without damage to the existing leads.
Conclusion The obstruction formed by the fibrous track around an extracted lead may persist despite what appears to be successful balloon
dilation. Inflation with a wire beside the balloon increases the effect eliminating the resistant obstruction without damaging
the leads.
Acknowledgements of Sources of Financial Support:Dr. Worley receives compensation in various forms from Medtronic, Pressure
Products, Guidant, and St Jude Medical. Dr. Gohn receives compensation in various forms from Medtronic. No financial support
was provided for the creation of this case report 相似文献
995.
996.
Seth Woodruff Guillaume Feugère Paula Abreu Joseph Heissler Marcia T. Ruiz Frank Jen 《Journal of thrombosis and thrombolysis》2016,42(4):494-504
Venous thromboembolism (VTE) is a common and serious complication in patients with cancer; treatment guidelines recommend extended therapy of ≥6 months with low-molecular-weight heparin (LMWH) for treatment and prevention of recurrent VTE (rVTE) in this population. This post hoc analysis used data from the CLOT study—a phase III, randomized, open-label, controlled study (N = 676)—to compare the efficacy and safety of dalteparin, a LMWH, versus vitamin K antagonist (VKA) for prevention of rVTE in patients with cancer and renal impairment (creatinine clearance <60 ml/min). Overall, 162/676 (24 %) patients had renal impairment at baseline. Patients received subcutaneous dalteparin 200 IU/kg once daily during month 1, followed by 150 IU/kg once daily for months 2–6; or VKA once daily for 6 months, with initial overlapping subcutaneous dalteparin 200 IU/kg once daily for ≥5 days until international normalized ratio was 2.0–3.0 for 2 consecutive days. Endpoints included the rates of rVTE (primary) and bleeding events. Overall, fewer dalteparin-treated patients (2/74 [2.7 %]) experienced ≥1 adjudicated symptomatic rVTE compared with VKA-treated patients (15/88 [17.0 %]; hazard ratio = 0.15 [95 % confidence interval 0.03–0.65]; p = 0.01). Bleeding event rates for both treatments were similar (p = 0.47). In summary, compared with VKA, dalteparin significantly reduced risk of rVTE in patients with cancer and renal impairment (p = 0.01) while exhibiting a comparable safety profile. This analysis supports dosing patients with renal impairment in accordance with patients with normal renal function; however, anti-Xa monitoring could be considered to further support safety in selected patients, particularly those with very severe renal impairment. 相似文献
997.
Maria Mercedes Binda 《Archives of gynecology and obstetrics》2015,291(5):955-957
Purpose
The peritoneum is the serous membrane that covers the abdominal cavity and most of the intra-abdominal organs. It is a very delicate layer highly susceptible to damage and it is not designed to cope with variable conditions such as the dry and cold carbon dioxide (CO2) during laparoscopic surgery. The aim of this review was to evaluate the effects caused by insufflating dry and cold gas into the abdominal cavity after laparoscopic surgery.Methods
A literature search using the Pubmed was carried out. Articles identified focused on the key issues of laparoscopy, peritoneum, morphology, pneumoperitoneum, humidity, body temperature, pain, recovery time, post-operative adhesions and lens fogging.Results
Insufflating dry and cold CO2 into the abdomen causes peritoneal damage, post-operative pain, hypothermia and post-operative adhesions. Using humidified and warm gas prevents pain after surgery. With regard to hypothermia due to desiccation, it can be fully prevented using humidified and warm gas. Results relating to the patient recovery are still controversial.Conclusions
The use of humidified and warm insufflation gas offers a significant clinical benefit to the patient, creating a more physiologic peritoneal environment and reducing the post-operative pain and hypothermia. In animal models, although humidified and warm gas reduces post-operative adhesions, humidified gas at 32 °C reduced them even more. It is clear that humidified gas should be used during laparoscopic surgery; however, a question remains unanswered: to achieve even greater clinical benefit to the patient, at what temperature should the humidified gas be when insufflated into the abdomen? More clinical trials should be performed to resolve this query.998.
Female sexual response is a complex, nonlinear progression from desire to arousal and orgasm. Diabetes may affect all these,
but it particularly affects arousal with decreased genital sensation and lubrication. Vaginal dryness and infections may lead
to dyspareunia. Predictors of sexual dysfunction in women include depression. Neither age, duration of diabetes, glycemic
control, nor complications predict sexual dysfunction in women as they do in men. Objective measures of decreased genital
sensation or lubrication do not correlate with a subjective sense of female sexual arousal disorder. Low androgens and possibly
estrogens may be etiologic, as may numerous medications used by patients with diabetes. Practitioners should recognize the
high prevalence of female sexual dysfunction (up to 50%) and potential increase, in tandem with that of diabetes. In the absence
of definitive treatment evidence, psychological counseling, improvised vaginal lubricants, and low doses of estrogens or androgens
have been used to relieve the personal distress of female sexual dysfunction. 相似文献
999.
Mykytenko J Reeves JG Kin H Wang NP Zatta AJ Jiang R Guyton RA Vinten-Johansen J Zhao ZQ 《Basic research in cardiology》2008,103(5):472-484
This study tested the hypothesis that inhibition of myocardial injury and modulation of mitochondrial dysfunction by postconditioning (Postcon) after 24 h of reperfusion is associated with activation of K(ATP) channels. Thirty dogs undergoing 60 min of ischemia and 24 h of reperfusion (R) were randomly divided into four groups: Control: no intervention at R; Postcon: three cycles of 30 s R alternating with 30 s re-occlusion were applied at R; 5-hydroxydecanoate (5-HD): the mitochondrial K(ATP) channel blocker was infused 5 min before Postcon; HMR1098: the sarcolemmal K(ATP) channel blocker was administered 5 min before Postcon. After 24 h of R, infarct size was smaller in Postcon relative to Control (27 +/- 4%* Vs. 39 +/- 2% of area at risk), consistent with a reduction in CK activity (66 +/- 7* Vs. 105 +/- 7 IU/g). The infarct-sparing effect of Postcon was blocked by 5-HD (48 +/- 5%(dagger)), but was not altered by HMR1098 (29 +/- 3%*), consistent with the change in CK activity (102 +/- 8(dagger) in 5-HD and 71 +/- 6* IU/g in HMR1098). In H9c2 cells exposed to 8 h hypoxia and 3 h of reoxygenation, Postcon up-regulated expression of mito-K(ATP) channel Kir6.1 protein, maintained mitochondrial membrane potential and inhibited mitochondrial permeability transition pore (mPTP) opening evidenced by preserved fluorescent TMRE and calcein staining. The protective effects were blocked by 5-HD, but not by HMR1098. These data suggest that in a clinically relevant model of ischemia-reperfusion (1) Postcon reduces infarct size and decreases CK activity after prolonged reperfusion; (2) protection by Postcon is achieved by opening mitochondrial K(ATP) channels and inhibiting mPTP opening. *P < 0.05 Vs. Control; (dagger) P < 0.05 Vs. Postcon. 相似文献
1000.