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91.
Osteoporosis is a chronic condition that reflects reduced bone strength and an associated increased risk for fracture. As a chronic condition, osteoporosis generally requires sustained medical intervention(s) to limit the risks for additional bone loss, compromise of skeletal integrity, and fracture occurrence. Further complicating this issue is the fact that the abrupt cessation of some therapies can be associated with an increased risk for harm. It is in this context that the COVID-19 pandemic has brought unprecedented disruption to the provision of health care globally, including near universal requirements for social distancing. In this Perspective, we provide evidence, where available, regarding the general care of patients with osteoporosis in the COVID-19 era and provide clinical recommendations based primarily on expert opinion when data are absent. Particular emphasis is placed on the transition from parenteral osteoporosis therapies. It is hoped that these recommendations can be used to safely guide care for patients with osteoporosis until a return to routine clinical care standards is available. © 2020 American Society for Bone and Mineral Research.  相似文献   
92.
Objective: We conducted a comparative analysis of gender differences in patients with primary psychotic disorders with concurrent substance use and in those with substance-induced psychoses. Methods: A total of 385 individuals admitted to psychiatric emergency departments with early-onset psychosis and recent substance use were interviewed at baseline and at six-month intervals for two years. Using a standardized research diagnostic assessment instrument, we classified patients at baseline into primary and substance-induced psychosis groups and analyzed the effects of gender on demographic, family, and clinical characteristics at baseline, the interaction of gender and diagnosis, and gender main effects on illness course, adjustment, and service use over the two-year follow-up period. Results: Women had better premorbid adjustment, less misattribution of symptoms, and a later age at onset of regular drug use compared to men. Women, however, showed greater depression and histories of abuse compared to men. Men had greater arrest histories. No interactions between gender and diagnosis were significant. Both genders in the primary and substance-induced psychosis groups showed clinical and functional improvement over the follow-up period despite the overall minimal use of mental health and substance abuse treatment services. Conclusions: Women and men with psychosis and substance use differ on several dimensions. Our findings suggest the need for gender-specific treatment programming across both diagnostic groups.  相似文献   
93.
94.

Rationale

Chronic pain is becoming a more common medical diagnosis and is especially prevalent in older individuals. As such, prescribed use of opioids is on the rise, even though the efficacy for pain management in older individuals is unclear.

Objectives

Thus, the present preclinical study assessed the effectiveness of chronic fentanyl administration to produce antinociception in aging rats (16, 20, and 24 months).

Methods

Animals were tested in a thermal sensitivity procedure known to involve neural circuits implicated in chronic pain in humans. Sensitivity to heat and cold thermal stimulation was assessed during 28 days of fentanyl administration (1.0 mg/kg/day), and 28 days of withdrawal.

Results

Fentanyl resulted in decreased thermal sensitivity to heat but not cold stimulation indicated by more time spent in the hot compartment relative to time spent in the cold or neutral compartments. Unlike previous findings using a hot-water tail withdrawal procedure, tolerance did not develop to the antinociceptive effects of fentanyl over a 28-day period of drug administration. The oldest animals were least sensitive, and the youngest animals most sensitive to the locomotor-stimulating effects of fentanyl. The effect on the antinociceptive response to fentanyl in the oldest group of rats was difficult to interpret due to profound changes in the behavior of saline-treated animals.

Conclusions

Overall, aging modifies the behavioral effects of opioids, a finding that may inform future studies for devising appropriate treatment strategies.  相似文献   
95.
96.
The cytoskeleton in Chediak-Higashi syndrome fibroblasts   总被引:2,自引:0,他引:2  
The Chediak-Higashi syndrome (CHS) trait is expressed in cultured human skin fibroblasts as an abnormal perinuclear concentration of moderately enlarged lysosomes. The cytoskeleton of CHS fibroblasts appears intact. Microtubules are normal in number and morphology, as assessed by colchicine binding studies, antitubulin immunofluorescence, and electron microscopy. Deformability by shear force is unaltered and microfilaments are abundant. However, CHS lysosomes appear to interact abnormally with the cytoskeleton, since the perinculear aggregation partially disperses after depolymerization of cell microtubules with colchicine. These results suggest that CHS is associated with a defect of either the lysosomal membrane itself or of lysosomal membrane- microtubule interaction.  相似文献   
97.
LaDuca  FM; Bettigole  RE; Bell  WR; Robson  EB 《Blood》1986,68(4):927-937
The contribution of von Willebrand factor (vWF)-platelet binding to platelet-collagen interaction was examined in vitro. The binding of vWF to platelets was mediated and regulated by ristocetin. Subthreshold concentrations of ristocetin (less than or equal to 1 mg/mL), insufficient to cause ristocetin-induced platelet aggregation (RIPA), were added to platelet-rich plasma (PRP) prior to the addition of collagen. The collagen-induced platelet aggregation (CIPA) was modified by ristocetin and the degree of alteration was dependent on the ristocetin concentration. Response as a function of ristocetin concentration was designated the Collagen-Platelet Aggregation Response (CoI-PAR). In normal PRP the CoI-PAR was a progressive inhibition followed by decreasing inhibition and then an enhanced response. The enhanced response occurred over a narrow range of ristocetin concentrations (0.8 to 1.0 mg/mL). In the absence of vWF (severe von Willebrand's disease, Type I, vWF less than 1%) the CoI-PAR was a progressive, eventually complete inhibition with no enhanced response (with ristocetin concentrations up to 3.0 mg/mL). With addition of vWF to this PRP an enhanced response was observed at a ristocetin concentration inversely proportional to the vWF level. PRP from a patient with severe Hemophilia A showed a response within the normal range. Subthreshold ristocetin did not cause plasma protein precipitation or platelet release of 3H-serotonin, nor induce micro platelet aggregate formation. Digestion of platelet membrane glycoproteins (GP(s] with chymotrypsin demonstrated that upon removal of GPI, RIPA was absent, CIPA retained and the CoI-PAR was progressive inhibition, with no enhancement. With removal of GPs I, II, and III, RIPA, CIPA, and the CoI-PAR were absent. A dose-response 125I-vWF- platelet binding occurred with increasing ristocetin concentrations which was unchanged by the addition of collagen. These results demonstrated that ristocetin-platelet association inhibited CIPA, and vWF-platelet binding enhanced platelet-collagen adhesion and platelet aggregation. The in vitro-enhanced CIPA represents a vWF-dependent aggregation of sufficient magnitude to overcome the inhibitory effect of ristocetin. These studies demonstrate an influential interaction of ristocetin, vWF, and collagen with the platelet membrane and imply an important hemostatic contribution of vWF-platelet binding in platelet- collagen interaction.  相似文献   
98.
Tom Drake 《Health economics》2014,23(2):248-252
Rational and analytic healthcare decision making employed by many national healthcare‐funding bodies could also be expected from global health donors. Cost effectiveness analysis of healthcare investment options presents the effectiveness of a particular action in proportion to the resources required, and cost effectiveness thresholds, while somewhat arbitrary, define the level at which the investment can be considered value for money. Currently, cost effectiveness thresholds reflect the national budget context or willingness‐to‐pay, which is problematic when making cross‐country comparisons. Defining a global minimum monetary value for the disability adjusted life year (DALY) would in effect set a global baseline cost effectiveness threshold. A global minimum DALY value would reflect a universal minimum value on human health, irrespective of a national provider's willingness or ability to pay. A minimum DALY value and associated threshold has both limitations and flaws but is justified on similar grounds to the Millennium Development Goals or the absolute poverty threshold and has the potential to radically improve transparency and efficiency of priority setting in global health. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
99.

Background

When retained hemothorax occurs, video-assisted thoracoscopy or thoracotomy is performed, but recently, tissue plasminogen activator (tPA) has been used. This study evaluated intrapleural tPA use for retained traumatic hemothoraces.

Methods

A retrospective review was conducted of trauma patients treated with intrapleural tPA for retained hemothorax. Data included demographics, past medical and surgical histories, injury details, treatment details, and outcomes.

Results

Seven patients (median age = 47 years, male = 6, blunt trauma = 6) met study criteria. All patients received a chest tube. Six patients later received computed tomography-guided drains for tPA infusion. Number of tPA treatments per patient varied from 1 to 5. Median total tPA dosage was 24 mg. Median time from injury to chest tube placement was 11 days and from chest tube placement to first tPA treatment was 4 days. No patients required a video-assisted thoracoscopy; however, 1 patient required thoracotomy. There were no deaths or bleeding complications attributed to intrapleural tPA.

Conclusion

Although future studies are needed to identify optimum treatment guidelines, intrapleural tPA appears to be a safe and efficacious treatment option.  相似文献   
100.
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