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More than 250,000 anterior cruciate ligament (ACL) injuries occur each year in the USA, and approximately 65% of these injuries undergo reconstructive surgery. Appropriate rehabilitation after ACL reconstruction can yield predictably good outcomes, with return to previous levels of activity and high knee function. At present, periodization is used at all levels of sports training. Whether conceptualized and directed by coaches, or by athletes themselves, competitors structure their training in a cyclic fashion, enabling athletes to best realize their performance goals. In practical application, sport physical therapists use periodization: postoperative “protocols” serve as rudimentary forms of periodization, albeit implemented over shorter time frames than that typically employed in preparation for competition. An ACL injury should not be considered a “simple” musculoskeletal pathology with only local mechanical or motor dysfunctions. Together with the psychological trauma and reduction in physical capacity, there is a cascade of events, including neurological insult to the central nervous system and reduction in afferences to the sensorimotor system. Rehabilitation should consider all these issues, and periodization would allow to better define and to plan aims and objectives to return athletes to their sport. Technological resources including advanced neuroimaging methods, virtual reality for injury risk screening and return to sport assessment, and interactive artificial reality-based neuromuscular training methods offer new approaches and tools to address this important biomedical problem. The cost and availability of many of these technologies will continue to decrease, providing greater availability, scientific rigor, and ultimately, utility for cost-effective and data-driven assessments.  相似文献   
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Among the numerous signaling pathways involved in tumorigenesis, PI3K‐AKT‐mTOR is a key one that regulates diverse cellular functions. However, its prognostic value in esophageal carcinoma remains unclear. In our study, we examined the immunohistochemical expression of phosphorylated (p‐) AKT, mTOR, p70S6K and 4E‐BP1 along with the mutational status of PIK3CA and AKT1 genes by High Resolution Melting Analysis and Pyrosequencing in 44 esophageal carcinomas. The results were correlated with the clinicopathological characteristics of the patients in an effort to define their possible prognostic significance. Total p‐mTOR cytoplasmic expression, assessed in 10 random areas, was positively correlated with tumor stage (Kruskal–Wallis ANOVA, I/II vs III/IV, p = 0.0500). Μoreover, maximum p‐mTOR cytoplasmic immunoexpression, estimated in hot spot areas, was positively associated with tumor grade (Mann–Whitney U test, I/II vs III, p = 0.0565). Interestingly, p‐4E‐BP1 immunoreactivity was negatively correlated with tumor histological grade (Mann–Whitney U test, I/II vs III, p = 0.0427). No mutation was observed in exons 9 and 20 of PIK3CA gene and in exon 4 of AKT1 gene. In conclusion, our findings depict the presence of activated PI3K/AKT/mTOR pathway in esophageal cancer bringing forward p‐mTOR and p‐4E‐BP1 for their potential role in esophageal carcinogenesis. Additional studies are warranted to validate our findings.  相似文献   
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PDE type 5 inhibitors (PDE5Is), such as sildenafil, tadalafil and vardenafil, are a class of drugs used to prolong the physiological effects of NO/cGMP signalling in tissues through the inhibition of cGMP degradation. Although these agents were originally developed for the treatment of hypertension and angina, unanticipated side effects led to advances in the treatment of erectile dysfunction and, later, pulmonary arterial hypertension. In the last decade, accumulating evidence suggests that PDE5Is may confer a wider range of clinical benefits than was previously recognised. This has led to a broader interest in the cardiovascular therapeutic potential of PDE5Is, in conditions such as hypertension, myocardial infarction, stroke, peripheral arterial disease, chronic kidney disease and diabetes mellitus. Here, we review the pharmacological properties and established licensed uses of this class of drug, along with emerging therapeutic developments and possible future indications.

Abbreviations

6MWD
6‐min walking distance
ACEI
ACE inhibitor
ARB
angiotensin receptor blocker
BPS
British Pharmacological Society
CCB
calcium channel blocker
CKD
chronic kidney disease
Cmax
maximum plasma/serum concentration
CTEPH
chronic thromboembolic pulmonary hypertension
CVD
cardiovascular disease
CYP2C19
cytochrome P450, family 2, subfamily C, polypeptide 19
CYP2C9
cytochrome P450, family 2, subfamily C, polypeptide 9
CYP2D6
cytochrome P450, family 2, subfamily D, polypeptide 6
CYP3A
cytochrome P450, family 3, subfamily A
CYP3A4
cytochrome P450, family 3, subfamily A, polypeptide 4
CYP450
cytochrome P450 enzyme family
DN
diabetic nephropathy
ED
erectile dysfunction
eGFR
estimated GFR
ERA
endothelin receptor antagonist
ET
endothelin
ET‐1
endothelin‐1
FGR
fetal growth restriction
GSK3B
glycogen synthase kinase 3 β
HbA1c
glycated Hb
HFpEF
heart failure with preserved ejection fraction
HFrEF
heart failure with reduced ejection fraction
IC50
half maximal inhibitory concentration
IUPHAR
International Union of Basic and Clinical Pharmacology
MI
myocardial infarction
mitoKATP
mitochondrial ATP‐sensitive potassium channels
NAION
nonarteritic anterior ischaemic optic neuropathy
Na+/K+‐ATPase
sodium–potassium pump
NOS1
neuronal NOS
NOS2
inducible NOS
NOS3
endothelial NOS
PAH
pulmonary arterial hypertension
PDE5I
PDE type 5 inhibitor
PH
pulmonary hypertension
PPHN
persistent pulmonary hypertension of the newborn
RCT
randomised controlled trial
RHTN
treatment‐resistant hypertension
RP
Raynaud''s phenomenon
sGC
soluble GC
SGLT2
sodium–glucose cotransporter 2
Tmax
time taken to reach the maximum plasma concentration
T2DM
type 2 diabetes mellitus
UACR
urinary albumin/creatinine ratio
V/Q
ventilation/perfusion
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