Section 3 Medical Literature 第三部分 医学文献
Part 1.
Urticaria1) is a vascular reaction of the skin characterized by the appearance of wheals2) which are elevated，whitish or reddish evanescent3) patches or streaks，generally surrounded by a red halo or flare，and associated with severe itching，stinging，or pricking sensations.These wheals are caused by localized edema.The eruption may also consist of macular erythema or papules and may be localized or generalized，the latter being the more common.Their size can vary from a small papule to the diameter of a large platter.The eruption usually favors the covered areas，such as the trunk，buttocks，or chest.The palms and soles are favorite sites for penicillin urticaria.Subcutaneous swellings，especially of eyelids or lips，may accompany the wheals，or occur alone.
Tissues other than the skin may be involved，which gives rise to symptoms such as coryza4)，asthma，and abdominal pain.Laryngeal edema may occur with severe urticaria,and this may lead to a life-threatening situation,especially in familial cases；in these，fresh frozen plasma intravenously may be specific.Therefore，prompt treatment with subcutaneous injections of epinephrine5) is mandatory.Intervenous injections of diphenhydramine6) or methylprednisolone7) succinate may be tried.Tracheostomy may be necessary.
Urticaria may be acute or chronic and also may have special forms.Acute hives are not infrequently experienced.Insect bites and stings are common urticaria inducers in many people.Dietary indiscretions，drugs such as penicillin and sulfonamides8)，or physical allergies may be the causes of acute urticaria.Often it is impossible to find the causative agent；however，if it can be found and removed，the hives involute rapidly.
When urticaria recurs frequently and over a period of several months or years,it is termed“chronic”urticaria.Finding the cause challenges not only the physician but also the patient，who must endure discomfort throughout all efforts at testing for the cause and finding efficacious medication for the relief of symptoms.
There are seemingly countless causes of urticaria.Food，drugs，infections，and emotional stress are the most frequent causes of chronic urticaria.Other factors will be treated in more detail under the discussion of the various types of urticaria.
注释：
1）urticaria 荨麻疹
2）wheal 疹块，风团
3）evanescent 短暂的
4）coryza 鼻炎，卡他
5）epinephrine 肾上腺素
6）diphenhydramine 盐酸苯海拉明
7）methylprednisolone 甲泼尼龙
8）sulfonamides（氨苯）磺胺
Part 2.
The cornea is a transparent avascular tissue comparable in size and structure to the crystal of a small wristwatch.It is inserted into the sclera1) at the limbus.The cornea functions as a refracting and protective membrane and a window through which light rays pass the route to the retina.The transparency of the cornea is due to its uniform structure,avascularity,and detumescence2).The cornea has many pain fibers,and most corneal lesions,superficial or deep(cornea foreign body,corneal abrasion，phlyctenule，interstitial keratitis)cause pain and photophobia.
The inflammation of the cornea may be caused by microbes,hypersensitivity,ischemia,nutritional deficiency,anesthesia from interruption of the sensory nerve supply，exposure，defects in the tear flow，and trauma.Central ulcerative keratitis is the most severe and destructive type.There is an outpouring of polymorphonuclear leukocytes into the cornea with a purulent infiltrate often combined with extensive stromal destruction.The leukocytes and the cornea itself produce collagenase that degrades corneal collagen.When severe，the cornea may perforate.And acute hypopyon3) ulcer is a severe bacterial inflammation of the cornea associated with pus in the anterior chamber(hypopyon)and a severe iridocyclitis4).The organism often has a focus in the lacrimal system.Frequently，the keratitis is preceded by mild trauma and loss of corneal epithelium，which allows entry of the organism，the ulcer is a dirty gray color，with overhanging margins.It causes marked thinning of the cornea，and the conjunctiva is violently inflammated.The bacteria are sensitive to many antibiotics，and the ulcer responds quickly to treatment.A concurrent pneumococcal dacryocystitis may necessitate dacryocystorhinostomy5) or occlusion of the canaliculi.
Herpes simplex virus(HSV)6) keratitis is the commonest cause of corneal ulceration in the world.The first symptoms are usually irritation，photophobia，and tearing.When the central cornea is affected，there is also some reduction in vision.Since corneal anesthesia usually occurs early in the course of the inflection，the symptoms may be minimal and the patient may not seek medical advice.There is often a history of fever blisters or other herpetic infection，but corneal ulceration can occasionally be the only sign of a recurrent herpetic inflection.The most characteristic lesion is the dendritic ulcer.It occurs in the corneal epithelium，has a typical linear pattern with a tendency to branch，and has terminal bulbs at its ends.Fluorescent staining makes the dendrite very easy to identify，but unfortunately herpetic keratitis can also stimulate almost any corneal infection and must be considered in the differential diagnosis of many corneal lesions.Disciform keratitis is the commonest complication of HSV infection.This round lesion is associated with moderate or severe edema of the affected stroma.Small or medium-sized white keratic precipitates sometimes lie directly under the lesions，and there may be folds in Descemet’s membrane.Disciform keratitis is usually associated with local or systemic immunosuppression.The treatment of HSV keratitis should be directed toward elimination of the virus from the cornea.In the immunocompetent patient，the inflection is self-limited and scarring minimal.Regrettably，the clinician often immunosuppresses the patient by using corticosteroids in eagerness to reduce local inflammation reduces disease.Virus in the epithelium can be readily eliminated by debridement of the affected epithelium，which is best accomplished by removing it carefully from the anesthetized corne with a tightly wound cotton-tipped applicator.A cycloplegic such as atropine or homatropine is then instilled into the conjunctival sac,and a pressure dressing is applied to promote healing.The patient should be examined daily and the dressing changed until the corneal defected has healed.Although mechanical removal of affected epithelium is the best treatment for dendritic keratitis，topical chemotherapy with antiviral agents is widely used.
注释：
1）sclera 巩膜(https://www.daowen.com)
2）detumescence 不肿胀
3）hypopyon 前房积脓
4）iridocyclitis 虹膜睫状体炎
5）dacryocystorhinostomy 泪囊鼻腔吻合术
6）herpes simplex virus 单纯疱疹病毒
Part 3.
Cutaneous Lymphoma1) Ms Xu,a 52-year-old female research chemist,has had a history of T cell lymphoma for eight years.She was initially treated with systemic chemotherapy with methotrexate2),until she contracted stomatitis3).Continued therapy with topical chemotherapeutic agents4) brought measurable improvement.She also had a history of hidradenitis5).
A recent physical examination showed diffuse erythroderma6） with scaling7） and hyperkeratosis8），plus alopecia9）.She had painful leukoplakia and ulcerations of the mouth and tongue.Ms Xu was hospitalized and given two courses of topical chemotherapy.She was referred to dental medicine for treatment of the oral lesions and was discharged in stable condition with an appointment for followup in four weeks.Her discharge medications included the application of 2 percent hydrocortisone ointment10） to the affected lesions qhs（1次/小时），Keralyt gel11） bid（2次/日）for the hyperkeratosis，and Dyclone12） and Benadryl13） for her mouth ulcers prn（必要时使用）.
注释：
1）cutaneous lymphoma 皮肤淋巴瘤
2）methotrexate［ˌmeθəˈtrεkset］氨甲蝶呤
3）stomatitis 口腔炎
4）topical chemotherapeutic agents 局部化疗剂
5）hidradenitis 汗腺炎
6）diffuse erythroderma 弥漫性红皮病
7）scales 鳞屑
8）hyperkeratosis 角化过度，眼角膜细胞增多
9）alopecia 脱发
10）hydrocortisone ointment 氢化可的松软膏
11）Keralyt gel Keralyt 凝胶
12）Dyclone 盐酸达克罗宁
13）Benadryl 苯海拉明