What is claimed is:
1. A method for the prevention or treatment of retinopathy which comprises administering to a mammal in need of such prevention or treatment an amount of a carbonic anhydrase inhibitor sufficient to prevent or treat retinopathy.
2. A method according to claim 1, wherein the retinopathy comprises diabetic retinopathy.
3. A method according to claim 2, wherein the diabetic retinopathy comprises non-proliferative diabetic retinopathy.
4. A method according to claim 2, wherein the diabetic retinopathy comprises diabetic macular edema.
5. A method according to claim 2, wherein the diabetic retinopathy comprises preproliferative or proliferative diabetic retinopathy.
6. A method according to claim 2 for the prevention of diabetic retinopathy in a diabetic not suffering from diabetic retinopathy which comprises administering to said diabetic an amount of a carbonic anhydrase inhibitor sufficient to prevent diabetic retinopathy.
7. A method according to claim 1, wherein the retinopathy comprises a vascular retinopathy.
8. A method according to claim 7, wherein the vascular retinopathy comprises branch retinal vein occlusion.
9. A method according to claim 7, wherein the vascular retinopathy comprises central retinal vein occlusion.
10. A method according to claim 7, wherein the vascular retinopathy comprises sickle cell retinopathy.
11. A method according to claim 7, wherein the vascular retinopathy comprises capillary occlusion or ischemia.
12. A method according to claim 1, wherein the carbonic anhydrase inhibitor is administered ophthalmically to the eye or eyes.
13. A method according to claim 1, wherein the carbonic anhydrase inhibitor is administered systemically.
14. A method according to claim 13, wherein the carbonic anhydrase inhibitor is administered orally.
15. A method according to claim 13, wherein the carbonic anhydrase inhibitor is administered parenterally.
16. A method according to claim 1, wherein the carbonic anhydrase inhibitor is dorzolamide.
17. A method according to claim 1, wherein the carbonic anhydrase inhibitor is acetazolamide.
18. A method according to claim 1, wherein the carbonic anhydrase inhibitor is brinzolamide.
19. A method according to claim 1, wherein the carbonic anhydrase inhibitor is methazolamide.
20. A method according to claim 1, wherein the carbonic anhydrase inhibitor is ethoxzolamide.
21. A method according to claim 1, wherein the carbonic anhydrase inhibitor is butazolamide.
22. A method according to claim 1, wherein the carbonic anhydrase inhibitor is dichlorphenamide.
23. A method according to claim 1, wherein the carbonic anhydrase inhibitor is flumethiazide.
24. A method according to claim 12, wherein the carbonic anhydrase inhibitor is dorzolamide, acetazolamide, methazolamide, ethoxyzolamide or brinzolamide.
25. A method according to claim 14, wherein the carbonic anhydrase inhibitor is dorzolamide, acetazolamide, methazolamide, ethoxyzolamide or brinzolamide.
26. A method according to claim 15, wherein the carbonic anhydrase inhibitor is dorzolamide or brinzolamide.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. An AGC circuit in a direct conversion receiver for multiplying a received high-frequency signal by a local signal with a frequency substantially the same as that of the high-frequency signal to directly convert into a baseband signal, amplifying the baseband signal using a baseband variable gain amplifying circuit having a variable gain amplifier, low-pass filter and a high-pass filter for cutting off a DC component as structural elements, and performing AD conversion and demodulation on the resultant, the AGC circuit comprising:
a power measuring section that measures reception power based on a signal subjected to AD conversion;
a gain calculating section that calculates a gain of the variable gain amplifier using information of a difference between measured reception power and a target convergence value;
a gain control section that controls the gain of the variable gain amplifier based on the calculated gain;
a filter control section that has a function of switching a cut-off frequency of the high-pass filter between at least high-and-low two frequencies; and
a gain variation amount detecting section that reports to the filter control section upon detecting that the gain of the variable gain amplifier varies by an amount equal to or greater than a predetermined amount as a result of control by the gain control section, wherein:
the filter control section switches the cut-off frequency of the high-pass filter to a high frequency upon receiving the report from the gain variation amount detecting section; and
the gain calculating section and the gain control section perform at least one of processing for increasing a range of gain variation per update and processing for shortening a period of the update during a period of time the cut-off frequency of the high-pass filter is switched to the high frequency.
2. The AGC circuit in the direct conversion receiver according to claim 1, wherein:
the filter control section switches the cut-off frequency of the high-pass filter to the high frequency and then switches the cut-off frequency to a low frequency again; and
the power measuring section does not measure reception power during a period of time the cut-off frequency of the high-pass filter is switched to the high frequency in a predetermined period in measuring average reception power for the predetermined period.
3. A CDMA receiver provided with the AGC circuit in the direct conversion receiver according to claim 1.
4. An AGC circuit in a direct conversion receiver for multiplying a received high-frequency signal by a local signal with a frequency substantially the same as that of the high-frequency signal to directly convert into a baseband signal, amplifying the baseband signal using a baseband variable gain amplifying circuit having a variable gain amplifier, low-pass filter and a high-pass filter for cutting off a DC component as structural elements, and performing AD conversion and demodulation on the resultant, the AGC circuit comprising:
a power measuring section that measures reception power based on a signal subjected to AD conversion;
a gain calculating section that calculates a gain of the variable gain amplifier using information of a difference between measured reception power and a target convergence value;
a gain control section that controls the gain of the variable gain amplifier based on the calculated gain;
a filter control section that has a function of switching a cut-off frequency of the high-pass filter between at least high-and-low two frequencies; and
a determining section that determines whether or not there is a high possibility of increasing a DC offset of a signal passed through the high-pass filter, based on information contained in a demodulated signal, or based on an operation state of the direct conversion receiver, and reports the determination result to the filter control section, wherein:
the filter control section switches the cut-off frequency of the high-pass filter to the high frequency upon receiving the report from the determining section; and
the gain calculating section and the gain control section perform at least one of processing for increasing a range of gain variation per update and processing for shortening a period of the update during a period of time the cut-off frequency of the high-pass filter is switched to the high frequency.
5. The AGC circuit in the direct conversion receiver according to claim 4, wherein:
the filter control section switches the cut-off frequency of the high-pass filter to the high frequency and then switches the cut-off frequency to a low frequency again; and
the power measuring section does not measure reception power during a period of time the cut-off frequency of the high-pass filter is switched to the high frequency in a predetermined period in measuring average reception power for the predetermined period.
6. A CDMA receiver provided with the AGC circuit in the direct conversion receiver according to claim 4.
7. A baseband variable gain amplifying circuit that is provided in a direct conversion receiver and that amplifies a baseband signal, comprising:
a variable gain amplifier that amplifies the baseband signal;
a high-pass filter that cuts off a DC component existing on a signal path of the baseband signal and that enables a cut-off frequency to be varied between at least low-and-high two frequencies;
a gain variation amount detecting section that detects an amount of gain variation at which the variable gain amplifier is set equal to or greater than a predetermined amount;
a filter control section that switches the cut-off frequency of the high-pass filter to a high frequency when the gain variation amount detecting section detects that the amount of gain variation is equal to or greater than the predetermined amount; and
a gain control section that performs at least one of processing for increasing a range of gain variation per update and processing for shortening a period of the update during a period of time the cut-off frequency of the high-pass filter is switched to the high frequency.
8. A baseband variable gain amplifying circuit that is provided in a direct conversion receiver and that amplifies a baseband signal, comprising:
a variable gain amplifier that amplifies the baseband signal;
a high-pass filter that cuts off a DC component existing on a signal path of the baseband signal and that enables a cut-off frequency to be varied between at least low-and-high two frequencies;
a DA converter that converts data of a gain at which the variable gain amplifier is set and digital data including data for instructing switching of the cut-off frequency of the high-pass filter into an analog signal;
a filter control section that switches the cut-off frequency of the high-pass filter based on a signal corresponding to the data for instructing switching of the cut-off frequency; and
a gain control section that performs at least one of processing for increasing a range of gain variation per update and processing for shortening a period of the update during a period of time the cut-off frequency of the high-pass filter is switched to the high frequency.