Category:ActinomycetalesConsultation on the creation of guidelines for the use of leukotriene receptor antagonists (LTRA) in the treatment of asthma.
Leukotriene receptor antagonists (LTRA) represent an important option in the treatment of asthma. Currently, there is no universally accepted set of guidelines for their use. A working group was set up to review the literature and to formulate recommendations for their use in asthma. In addition, all significant adverse effects, the most common being cutaneous reactions (urticaria, angioedema), and their relationship with the use of LTRA, were reviewed. The main conclusion was that the risk of cutaneous reactions is low and easily manageable. On the other hand, asthma exacerbations were not prevented as the response rates (both under control of symptoms and symptoms plus need for rescue medication) were lower than the reported in previous studies. The working group recognized that these events are more common with more prolonged treatment, especially in patients with severe asthma. There is evidence that the response to LTRA may be greater in those with persistent eosinophilic airway inflammation, and the group recommended that treatment should be initiated in such patients. The group also recommended that patients are regularly monitored to assess the response to treatment and that treatment be adjusted accordingly. In conclusion, the recommendations for the use of LTRA in the treatment of asthma are that: (i) treatment should be initiated in patients with persistent eosinophilic airway inflammation and (ii) treatment should be initiated at the lowest dose and increased slowly to a dose that controls the symptoms and as long as the patient tolerates it.Conventional zippered type elastic sport or swim shorts have a plurality of elongated elastic tapes secured to an inner surface of the shorts along the edges of a central opening. The tapes are generally the same size and shape and are sewn along the edges of the opening to define the leg and waist edges of the shorts. U.S. Pat. No. 4,834,306 is representative of the state of the art.
A problem with such designs is that the tapes are of the same length and shape and are sewn to the sides of the central opening. This leaves the outer surface of the waist edge of the shorts undulated or roughened and uncomfortable to the wearer. This roughness can be reduced by adding tape to the outer surface of the waist edge and similarly to the leg edges. However, when tapes are 01e38acffe
Category:Cryptococcosis
Category:Species described in 2004
Category:Fungi of AfricaQ:
Doesn't repeating a string in a list of strings work the same as printing it?
I am reading through the Book Hacker News in Python 3.0 and the author is mentioning that it's better to repeatedly print a string rather than putting it in a list to avoid the overhead of creating the string each time. However, it also says this:
"As soon as the string is in a list, Python starts to look it up again"
Why does adding a string to a list cause Python to look it up again? Isn't simply repeating the same string in a list faster than iterating over it?
A:
Python's string objects are immutable.
Lets assume that the string is 'Hello, I am a string', and you put it in a list like so:
x = ['Hello, I am a string']
Now you need to do look up the string in a dictionary (dict, specifically) to get the string's value (as the name is not known at the point of writing).
As such, for each string in the list, Python has to do a lookup in the dictionary (a database if you will) to get the string's value, and then this value has to be converted to a byte string (a bytes object) before it can be printed.
This is the only difference I can see.
A short example that demonstrates the difference between the two scenarios:
>>> x = ['Hello, I am a string']
>>> import sys
>>> sys.getsizeof(x)
100
>>> x = [x]
>>> sys.getsizeof(x)
36
As you can see, the first approach (just adding a string to a list) involves a lot more overhead than adding the same string to a list, as the string has to be looked up from a dictionary.
A:
You're right. One of the reasons is that Python 2.x strings aren't really first class objects in the sense that they aren't really assignable like other builtin types. They are immutable, and they don't implement hashable.
When you put them in a list, they get immutable so they can't be changed or modified.
If you really want to use a list, you should use an immutable type instead.
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