什麼是房屋建造
裝配和修築建築物的技術和工業。早期人類主要用簡單的方式建造遮風避雨的處所。建築材料來自土地,建造受限於材料和施工者的技巧。施工的第一步是打地基,施工者安裝結構系統,結構材料(磚石、泥或原木)可用作骨架和圍牆。傳統的樑柱體系(post-and-beam system)最後被框架結構取代,施工者變成擅長用各種覆面(骨架外牆)和塗飾,來做封填與防火工作。鋼骨建築物通常用幕牆(curtain wall)圍蓋。在現代建築中,包覆建築物骨架只是個開始,各種專家自那時起就開始在內部大量施工,如安裝室內給排水設施、電子管線、HVAC(即供暖、通風和空氣調節配備)、窗、樓面覆面層(floor covering)、抹灰泥工作、線腳(裝飾線條)、瓦/磚和隔間等等。亦請參閱architecture。
building construction
Techniques and industry involved in the assembly and erection of structures. Early humans built primarily for shelter, using simple methods. Building materials came from the land, and fabrication was dictated by the limits of the materials and the builder's hands. The erection sequence involved, as now, first placing a foundation (or using the ground). The builder erected the structural system; the structural material (masonry, mud, or logs) served as both skeleton and enclosure. Traditional bearing-wall and post-and-beam systems eventually gave way to framed structures, and builders became adept at sealing and fireproofing with a variety of claddings (exterior coverings) and finishes. Steel-framed buildings are usually enclosed by curtain walls. In modern-day construction, sheathing the skeleton of the building is only the beginning; specialists then begin the bulk of the work inside, installing plumbing, electrical wiring, HVAC (heating, ventilating, and air-conditioning), windows, floor coverings, plasterwork, moldings, ceramic tile, cabinets, and other features. See also architecture.
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什麼是浸潤
組織內侵入了異常的細胞或出現了正常情況下不應出現的機體細胞,以及某些病變組織向周圍擴充套件的現象。在細胞內或間質中出現異常的物質、或原有的某些物質的堆積過多也稱為浸潤。有的變性或沉積也稱為浸潤。浸潤大多為病理性的,但有時是為了治療目的而人為的。它們...
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什麼是細菌性感染
細菌引起的感染。包括醫院外感染和醫院內感染。引起醫院外感染最常見的細菌為革蘭氏陽性菌如金黃色葡萄球菌、肺炎鏈球菌、化膿性鏈球菌和革蘭氏陰性的大腸桿菌、流感嗜血桿菌等;引起醫院內感染的則多為有耐藥性的金黃色葡萄球菌、表皮葡萄球菌、腸球菌、克雷伯...
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什麼是腎性骨營養不良
由慢性腎功能衰竭導致的骨代謝病,表現為鈣磷代謝障礙、酸鹼平衡失調、骨骼畸形,並可引起繼發性甲狀旁腺功能亢進。腎性佝僂病常由慢性腎小球腎炎、慢性腎盂腎炎、腎結核、腎腫瘤、腎結石或先天性腎盂積水引起。由於腎小球遭到破壞,間質纖維化、腎小管萎縮、尿濃縮...
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什麼是三叉神經痛
面部三叉神經感覺支分佈區出現的短暫發作性疼痛。多發病於中年以上,40歲以上佔70~80%,而70歲以上又逐漸減少。患者中女性多於男性,兩者之比為3:2。多為一側性,雙側受罹者在5%以下。以三叉神經第二支(上頜支)受侵犯者最常見,其次為第三支(下頜支),第二、三支同時患病者亦常見...