The sigmoid colon is the last section of the bowel — the part that attaches to the rectum. It’s about a foot and a half long (around 40 centimeters) and is shaped like the letter “s.” Its job is to hold feces until you’re ready to go to the bathroom.

乙状结肠包含大量的肌肉组织。muscles in the sigmoid are arranged two ways: Some bundles of muscle tissue run up and down the length of the sigmoid tube, and some bundles are arranged in circular bands around the tube.

The circular bands of muscle pinch the tube into small sacs called haustra, making the sigmoid look a little bit like a string of plump beads. As the muscles contract, the haustra shift and move, pushing feces along the bowel tract.

结肠含有四层组织。内层是粘膜。粘液使身体保持粪便物质中的所有细菌，并且还有助于粪便通过管滑动。

在粘液膜旁边是一层结缔组织，血管和神经。这层组织在消化的食物中脱离了任何剩余的营养物质。神经控制你的冲动去洗手间。

第三层由肌肉制成，以沿矩形管提伸粪便，并且通过分泌液体通过在移动时通过使器官撕裂器官撕裂的液体来保护血清水的第四层的光滑上皮组织。

The sigmoid portion of the bowel sits down low in the abdominal cavity, near the uterus in in women and near the bladder in men.

矩形的主要工作是用作粪便物质的保持室，直到它可以从你的身体移出。

消化食物到达乙状结肠,金属氧化物半导体t of the nutrients have already been extracted by the stomach and small intestines, but the sigmoid can extract water and vitamins from the feces while it’s waiting to be expelled.

If there’s a problem in your sigmoid colon, you’ll probably feel abdominal疼痛. You might feel nauseated or lose your appetite, and you might experience either diarrhea or constipation.

You might also notice blood in your stool. Sometimes people with sigmoid colon problems also feel fatigued, become anemic, or lose weight.

Polyps

Polyps are lumps of tissue in the colon, most of which are not cancerous. Anyone can get them, but they are more likely to form as you get older. Smoking and being overweight also increase your risk.

It’s important to have a colonoscopy to find and remove polyps because they can get bigger over time, and the larger the polyp, the more likely it is to become cancerous.

结直肠癌

The 美国癌症学会 reports that colorectal cancer is the third most common cancer in the United States, with more than 145,000 new cases expected to be diagnosed this year.

当异常细胞在结肠内发生异常，通常以息肉产生结肠癌。癌细胞可以通过器官壁从结肠的内层扩散，并且最终进入血管和淋巴系统，如果未经处理。

早期诊断提高了您的恢复机会，因此获得定期冒号筛查是一个好主意，特别是如果您有任何一个危险因素或症状.

Ulcerative colitis

这种疾病导致开放的疮形成在肠道内，导致疼痛有时会严重。这是一个长期的疾病，但是有可能经历一段症状的人可能会遇到任何症状。

根据这一点 National Institute of Diabetes and Digestive and Kidney Diseases , you may be at higher risk for ulcerative colitis if you eat a high-fat diet, if the disease seems to run in your family, or if your intestinal immune system is overly sensitive. Jewish people are also at higher risk for developing ulcerative colitis.

如果您关注溃疡性结肠炎，胃肠学家可能能够帮助诊断您的症状。

Crohn’s disease

Like ulcerative colitis,Crohn’s diseasecauses inflammation, swelling, and pain in the intestinal tract. Most of the time, Crohn’s disease affects the upper gastrointestinal tract, but it can occur anywhere, including the sigmoid colon.

Crohn’s disease can lead to infections in your intestines and in other parts of your body, and it can become life-threatening for some people, so it’s important to talk to a doctor and start treatments early to prevent severe complications from happening.

瘘管

A gastrointestinal瘘管is an opening in your bowel that allows gastric fluid to leak into other parts of your body. These openings usually occur after you’ve had surgery or a procedure in your abdominal area.

瘘管may also develop if you’ve had an inflammatory bowel disease like Crohn’s for a long time. Gastrointestinal fistulae can lead to sepsis, an extremely dangerous systemic infection.

可以修复或治疗瘘管，以防止它们引起严重问题。它们可以缝合，胶合，排出，并有效地用抗生素治疗，因此如果您怀疑您可能已经开发了一个。

憩室疾病

Diverticula are small balloon-like sacs that push outward through weak spots in your intestinal wall. Most of the time diverticula don’t cause any symptoms at all, but they can occasionally become painful and problematic.

憩室可能被阻止。它们可以形成脓肿，撕裂，呼吸脓液或血液进入身体的其他部位。这些并发症可能是危险的，所以如果你发烧，开始呕吐，或在腹部地区感到柔软，请去看医生寻求帮助。

Volvulus

Volvulus是婴儿肠形成的方式的问题，导致一部分肠扭曲或折叠自身。这种情况会导致切断堵塞和血液供应。

拥有这种情况的婴儿将有疼痛，腹部腹胀，恶心和呕吐。它们也可以有黑暗或红色的排便。

It’s really important to respond quickly if these symptoms occur, because this condition can be life-threatening. Doctors can often repair the damaged part of the baby’s bowel.

根据您的结肠问题的性质，您可以看到胃肠学家，肿瘤学家，放射科医师或结肠直肠外科医生。

Colonoscopy

结肠镜片让您的医生检查您的结肠的健康状况。一个薄，柔性管，带有微小相机，插入您的肛门。医生可以在检查室的屏幕上看到你的结肠的衬里。您可能会镇定此程序。

sigmoidoscopy.

Asigmoidoscopy.lets a doctor check just the sigmoid part of your intestine, using a slender tube with a light source and camera attached to it. During the procedure, air will be used to open up your intestine so the doctor can see it clearly. You may or may not be sedated for this procedure.

Biopsy

A.直肠活检，您的医生将删除您的Strecum或Sigmoid的一小部分，以便在实验室中进行测试。该过程通常在血管镜检查期间进行，因此您可能会醒着，但活检通常不会受到伤害。

Surgery

如果您的乙状病受伤或受疾病损坏，您可能必须在手术修理或重新分区. These procedures may be done with a traditional incision or they may be performed via laparoscopy.

乙状物质是大肠的下三分之一。它连接到你的直肠，它是你身体的一部分，在你去洗手间之前留下粪便。

If you have a sigmoid problem, you’re likely to feel pain in your lower abdomen. You may also have other symptoms like blood in your stool, loss of appetite, anemia, abdominal bloating, or fatigue.

如果您有这些症状，那么看到一种胃肠学家是很重要的，因为一系列疾病会影响结肠，包括癌症和克罗恩病等危及生命的病症。