Gula Darah

Dalam ilmu kedokteran, gula darah adalah istilah yang mengacu kepada tingkat glukosa di dalam darah. Konsentrasi gula darah, atau tingkat glukosa serum, diatur dengan ketat di dalam tubuh. Glukosa yang dialirkan melalui darah adalah sumber utama energi untuk sel-sel tubuh.

Umumnya tingkat gula darah bertahan pada batas-batas yang sempit sepanjang hari: 4-8 mmol/l (70-150 mg/dl). Tingkat ini meningkat setelah makan dan biasanya berada pada level terendah pada pagi hari, sebelum orang makan.

Diabetes mellitus adalah penyakit yang paling menonjol yang disebabkan oleh gagalnya pengaturan gula darah.

Meskipun disebut "gula darah", selain glukosa, kita juga menemukan jenis-jenis gula lainnya, seperti fruktosa dan galaktosa. Namun demikian, hanya tingkatan glukosa yang diatur melalui insulin dan leptin.

Pengaruh langsung dari masalah gula darah

Bila level gula darah menurun terlalu rendah, berkembanglah kondisi yang bisa fatal yang disebut hipoglikemia. Gejala-gejalanya adalah perasaan lelah, fungsi mental yang menurun, rasa mudah tersinggung, dan kehilangan kesadaran.

Bila levelnya tetap tinggi, yang disebut hiperglikemia, nafsu makan akan tertekan untuk waktu yang singkat. Hiperglikemia dalam jangka panjang dapat menyebabkan masalah-masalah kesehatan yang berkepanjangan pula yang berkaitan dengan diabetes, termasuk kerusakan pada mata, ginjal, dan saraf.

Mekanisme pengaturan gula darah

Tingkat gula darah diatur melalui umpan balik negatif untuk mempertahankan keseimbangan di dalam tubuh. Level glukosa di dalam darah dimonitor oleh pankreas. Bila konsentrasi glukosa menurun, karena dikonsumsi untuk memenuhi kebutuhan energi tubuh, pankreas melepaskan glukagon, hormon yang menargetkan sel-sel di lever (hati). Kemudian sel-sel ini mengubah glikogen menjadi glukosa (proses ini disebut glikogenolisis). Glukosa dilepaskan ke dalam aliran darah, hingga meningkatkan level gula darah.

Apabila level gula dara meningkat, entah karena perubahan glikoen, atau karena pencernaan makanan, hormon yang lain dilepaskan dari butir-butir sel yang terdapat di dalam pankreas. Hormon ini, yang disebut insulin, menyebabkan hati mengubah lebih banyak glukosa menjadi glikogen. Proses ini disebut gliogenosis), yang mengurangi level gula darah.

Diabetes mellitus tipe 1 disebabkan oleh tidak cukup atau tidak dihasilkannya insulin, sementara tipe 2 disebabkan oleh respon yang tidak memadai terhadap insulin yang dilepaskan ("resistensi insulin"). Kedua jenis diabetes ini mengakibatkan terlalu banyaknya glukosa yang terdapat di dalam darah.

Sebagian orang merasa mengantuk atau fungsi kognitifnya menurun beberapa jam setelah makan, yang mereka yakini berkaitan dengan menurunnya tingkat gula darah, atau "gula darah rendah". Untuk informasi lebih lanjut, lihat: idiopathic postprandial syndrome hypoglycemia.

Samsung L700 3G Phone

Samsung has announced Samsung L700 mobile phone which is a Candybar style Quadband GSM and 3G capable mobile phone which features 256K colors display, integrated 2.0 Megapixel camera with video recording, microSD memory slot, GPRS, EDGE, 3G UMTS, MP3 Media Player plus FM Radio with RDS.

The Samsung SGH-L700 is quad-band GSM 850 / 900 / 1800 / 1900 MHz network ready and offers 3G functionality over UMTS 2100 network. The L700 is equipped with large 2.1-inch 265K colors capable, QVGA TFT screen having 176 x 220 pixels screen resolution. The screen allows up to 11 text lines with 4 lines reserved for service needs.

The Samsung L700 mobile phone is equipped with 40-MB of internal shared memory and it supports microSD memory card with upto 8-GB capacity with hot-swap functionality for external memory with virtually limitless storage capacity.

Supporting Polyphonic (64 channels) ringtones and MP3 ringtones, Samsung L700 mobile phone allows upto 1000 entries phonebook with Photo ID caller identification feature and offers upto 30 dialed, 30 received and 30 missed calls records.

Weighting just about 107 gms, the Samsung L700 mobile phone features a single integrated 2.0 Megapixels digital camera with maximum still picture resolution of 1600 x 1200 pixels and it offers Autofocus, 3.3X digital zoom and built-in LED flash light. The Samsung L700 phone also allows picture storage in standard JPEG format in handset memory or in extended memory and the digital camera also offers Photo effects and option for Photo quality settings while shooting still pictures.

The Stylish Samsung L700 mobile phone is also capable of recording video with sound in QCIF resolution at 15fps offers quality images. Video recording and decoding formats in H.263, 3GPP, WMV and MPEG4 video formats. The Samsung i550 video playback supports WMV, MPEG4, 3GPP and H.263 Video Formats.

The Samsung SGH-L700 mobile phone is powered by Symbian OS 9.2 Series 60 OS andis available in several colors including Titan Silver, Grayish Brown, Chargoal Gray, Noir Black, Rose Pink, and Lilac Violet.

In addition, the Samsung L700 mobilephone has a powerful speakerphone is included to give users a hands-free comfort.

The Samsung L700 mobile phone also sports a built-in MP3 media player which which supports MP3, ACC, ACC+, eAAC+, WAV, MIDI and WMA music formats. Advanced Audio Distribution Profile (A2DP) Bluetooth for stereo sound feature in Samsung SGH-L700 allows listening to music on bluetooth compatible headset absolutely wire-free.

The Samsung L700 mobilephone allows downloading JAVA-enabled games, pictures, ringtones and other sounds, as well as text files using WAP 2.0 browse over GPRS or fast 3G internet connection.

The Samsung L700 mobilephone offers range of connectivity including Bluetooth v2.0 with A2DP, GPRS Class 10 - with upto 48 kbps speed, and EDGE Class 10 - with upto 236.8 kbps speed, 3G connection with upto 384 kbps speed.

EDGE network connection allows ultra fast data transmissions, and faster downloads and file transfers. Bluetooth technology enables communication with other Bluetooth compatible devices and gadgets such as color printers, PDAs and laptops for instant sync-ups, data transfer and print jobs in a flash.

For wired access, Samsung SGH-L700 mobile phone handset offers USB v2.0/v1.1 for conventional hook-ups. MMS and EMS is a breeze with JAVA technology and WAP 2.0 providing easy access to a wide range of content and applications. The user can send & receive emails using built-in email client which supports POP3, SMTP & IMAP4 email protocols.

The Samsung L700 also offers email client software and document viewing software for Microsoft Excel, and MS Word, and PDF documents.

The Samsung L700 phone also features integrated FM Radio tuner with 20 station memory and auto-tuning feature.

Available in choice of several colors, the Samsung L700 mobile phone is equipped with offers range of applications including Calendar, Scheduler, To do list, Clock, World time, Alarms, Currency Converter, Calculator, Memo Book, Stop Watch, and Count Down Timer.

The Samsung L700 mobile phone comes with Standard Li-Ion 960 mAh battery which allows upto 500 hours of stand-by time and incredible 9 hours of talk time on full charge.


Samsung L700 Mobile Phone Features
Quad-band: GSM 850 / 900 / 1800 / 1900 MHz
3G UMTS 2100
256K Colors, 176 x 220 pixels, 2.1-inch QVGA TFT screen
40-MB internal memory (shared)
microSD memory card, upto 8-GB, hot-swap functionality
30 Dialed, 30 Received, 30 Missed Calls
1000 entries phonebook with Photo call
2.0 Megapixel Camera, 1600 x 1200 pixels resolution, 3.3x digital zoom, Autofocus, LED flash, Photo Effects
Video recording, MPEG4, 3GPP and H.263 Video Formats
Video Player, Supports WMV, MPEG4, 3GP and H.263 Video Formats
Media Player supporting MP3, AAC, AAC+, eAAC+, WAV, MIDI, OGG, ASF and WMA audio file formats
Polyphonic (64 channels) ringtones / MP3 ringtones
GPRS Class 10, 32 - 48 kbps speed
EDGE Class 10, 236.8 kbps speed
3G upto 384 kbps
Bluetooth v2.0 + A2DP
USB v2.0 port
FM Radio with RDS
WAP 2.0, HTML (PocketIE)
SMS, MMS, EMS, IM, Email
WAP 2.0 Browser, NetFront Browser
MS Office Document Viewer, Microsoft Excel, Word, Powerpoint, PDF
Voice Memo
PDF Viewer
Built-in handsfree speakphone
Java MIDP 2.0
Voice Memo
Colors - Noir Black, Titan Silver, Grayish Brown, Chargoal Gray, Rose Pink, Lilac Violet
Applications - Calendar, Scheduler, To do list, Clock, World time, Alarms, Currency Converter, Calculator, Memo Book, Stop Watch, Count Down Timer
Li-Ion 960 mAh standard battery
Stand-by: Up to 500 hours
Talk time: Up to 9 hours
Dimension: 109 x 46 x 12.8 mm
Weight: 107 gms

Quad-band and 3G capable Samsung SGH L700 mobile phone with 2.0 MP camera, MP3 player, FM Radio along with Bluetooth v2.0+A2DP wireless connectivity is available for Rs. 7,150 plus local taxes. Visit www.samsung.com/in for more details.