首页 | 官方网站   微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   6572篇
  免费   292篇
  国内免费   89篇
医药卫生   6953篇
  2022年   37篇
  2021年   109篇
  2020年   68篇
  2019年   58篇
  2018年   123篇
  2017年   75篇
  2016年   107篇
  2015年   114篇
  2014年   140篇
  2013年   200篇
  2012年   298篇
  2011年   256篇
  2010年   154篇
  2009年   151篇
  2008年   285篇
  2007年   308篇
  2006年   292篇
  2005年   263篇
  2004年   256篇
  2003年   240篇
  2002年   251篇
  2001年   288篇
  2000年   232篇
  1999年   235篇
  1998年   104篇
  1997年   108篇
  1996年   70篇
  1995年   77篇
  1994年   58篇
  1993年   73篇
  1992年   156篇
  1991年   155篇
  1990年   156篇
  1989年   172篇
  1988年   132篇
  1987年   145篇
  1986年   143篇
  1985年   97篇
  1984年   88篇
  1983年   58篇
  1982年   31篇
  1980年   45篇
  1979年   65篇
  1978年   39篇
  1977年   41篇
  1975年   30篇
  1972年   30篇
  1971年   37篇
  1969年   34篇
  1968年   34篇
排序方式: 共有6953条查询结果,搜索用时 109 毫秒
11.
A 72-year-old fisherman who was positive for the HCV antibody developed an annular, erythematous, infiltrated lesions on sun-exposed areas. The lesions were diagnosed as annular elastolytic giant cell granuloma both clinically and histologically. Topical corticosteroid and cryotherapy with liquid nitrogen for several months failed to improve the lesions. We then started dapsone, a known anti-oxidant, at 50 mg/day. A month later, the margins of the erythematous lesions faded, and the infiltration gradually decreased. No recurrence has been observed for one year after the start of the therapy. Anti-oxidative therapy appears to be effective for annular elastolytic giant cell granuloma and could be an alternate therapy for refractory granulomatous disease.  相似文献   
12.
We established a novel murine model of pharyngeal candidiasis maintaining stable yeast population and local symptoms characteristic of pharyngeal thrush. The persistent Candida-infection was prolonged by inhalation of beclomethasone dipropionate corticosteroid. The severity of infection lesions was evaluated by determining viable cell number of Candia albicans and scores representing symptomatic curd-like white patch on pharyngeal tissue. The utility of this model was shown by the disappearance of lesions and fungal cells after treatment with fluconazole (FLCZ). The model would be useful for evaluating new chemotherapeutic or immunotherapeutic approaches against pharyngeal candidiasis, as well as in pathological studies.  相似文献   
13.
By the combined use of agar diffusion, agar vapor and agar vapor-inhibitory assays, contribution of the vapor activity of essential oils was quantitatively estimated. The test organisms were Trichophyton mentagrophytes and Aspergillus fumigatus. Agar vapor assay was used to confirm the vapor activity of the oils. The parameter delta defined as a contribution index of the vapor activity was calculated by (1 - b-c/a-c) x 100, where a is inhibitory diameter in the diffusion assay, b is inhibitory diameter in the vapor-inhibitory assay and c is diameter of the sealed ring in the vapor-inhibitory assay (21 mm). Many of the essential oils examined showed a delta value near 100, thus providing the major contribution of the vapor activity to the inhibitory diameter. Essential oils containing aldehyde as major constituent showed low delta value, indicating the major inhibition was due to agar diffusion. Major essential oil components behaved similarly; the delta value was increased in the following order: aldehyde < phenol < alcohol < ester, oxide, hydrocarbon, indicating the enhanced contribution of the vapor activity in that order.  相似文献   
14.
To investigate the chewing patterns of patients with TMJ disorders, analysis of mandibular movement was performed in 25 normal subjects and 150 patients with stomatognathic dysfunction using the Sirognathograph analyzing system. Patients with TMJ disorders demonstrated different chewing patterns than those of normal subjects. Chewing patterns in the frontal, horizontal, and sagittal projections were classified into four, two, and two different patterns, respectively, and each distinct chewing pattern appeared to be associated with a specific TMJ disorder.  相似文献   
15.
The effects of 12 essential oils, popularly used as antifungal treatments in aromatherapy, on growth of Candida albicans were investigated. Mycelial growth of C. albicans, which is known to give the fungus the capacity to invade mucosal tissues, was inhibited in the medium containing 100 micro g/ml of the oils: lemongrass (Cymbopogon citratus), thyme (Thymus vulgaris), patchouli (Pogostemon cablin) and cedarwood (Cedrus atlantica). Not only lemongrass oil but also citral, a major component of lemongrass oil (80%), in the range of 25 and 200 micro g/ml inhibited the mycelial growth but allowed yeast-form growth. More than 200 micro g/ml of citral clearly inhibited both mycelial and yeast-form growth of C. albicans. These results provide experimental evidence suggesting the potential value of lemongrass oil for the treatment of oral or vaginal candidiasis.  相似文献   
16.
The effect of prolonged dietary administration of the peroxisomeproliferating plasticizer di(2-ethylhexy1)phthalate (DEHP wasstudied on liver carcinogenesis initiated by N-2- fltuorenylmxhmide(FAA) and with that of the neoplasm-promoter phenobarbital (PB).Also, DEHP was studied as an initiator by giving it in placeof FAA before PB. Male rats were fed FAA for 7 weeks to inducebepatocellular altered foci, and were subsequently given nochemical, 12 000 p.p.m. DEHP or 500 p.p.m. PB for 24 weeks inthe diet. In the rats fed DEHP, substantial hepatomegaly andperoxisome proliferation were induced. No evidence of indudionof hepatacellular altered foci or hepatic neoplasms was foundeither when DEHP was given alone for 24 weeks or for 7 weeksfollowed by PB. Also, DEHP fed for 24 weeks had no promotingeffect on liver altered foci that were induced by FAA and producedlittle or no enhancement of the occurrence of FAA-induced liverneoplasms. In contrast, PB exerted a marked enhancing effecton foci and substantially increased the incidence and multiplicityof liver neoplasms. Thus, the findings demonstrate that DEHPdid not have either a rapid initiating activity, a significantsequential syncarcinogenic activity, or a promoting effect onliver carcinogenesis under conditions in which numerous agentswith such activities have been identified.  相似文献   
17.
From 1977 to 1988, four hundred and sixty-five patients received total or proximal gastrectomy for advanced gastric cancer without leaving a tumor mass at National Cancer Center Hospital. Of these, 182 patients received distal pancreatectomy (PS) and 123 received pancreas-preserving operation with removal of the splenic artery (PP). The 5-year survival rate for the PS group (32.0%) was significantly lower than 61.0% for the PP group. Concerning grades of cancer stage, the 5-year survival rates for the PP group were better than those for the PS group in stages 1, 2 and 3. Seventy-four of the 465 patients were found to have histologically proven metastatic nodes around the splenic artery. Their 5-year survival rates were 9.2% for the PS group (n = 46) and 32.7% for the PP group (n = 13) respectively. Considering the difference in the background factors, these data suggest the effectiveness of the pancreas-preserving operation for advanced gastric cancer even with microscopic lymph node metastasis around the splenic artery. The pancreas-preserving operation with removal of the splenic artery might be indicated for the patient without definite macroscopically metastatic lymph node around the splenic artery.  相似文献   
18.
19.
The carcinogenic activity of endogenously synthesized N-nitrosobis(2-hydroxypropyl)amine(BHP) was investigated in male Wistar rats administered bis(2-hydroxypropyl)amine(BHPA) mixed in powder diet at a concentration of 1%, and sodiumnitrite (SN) dissolved in distilled water at concentrationsof 0.15 and 0.3%, for 94 weeks. Urinary excretion of BHP wasdetected in rats given 1% BHPA and 0.3% SN but not in the groupsreceiving either of these precursors alone. Nasal cavity, lung,esophagus, liver and urinary bladder tumors were found in animalstreated with combinations of 1% BHPA and 0.15 or 0.3% SN, suggestingthat the target organs of the endogenously synthesized BHP aresimilar to those affected when the carcinogen is administeredexogenously. The incidences of nasal cavity and lung tumorsreached 74 and 58% in rats given 1% BHPA and 0.3% SN, respectively.Tumors at sites other than target organs were only found atlevels similar to those previously reported for spontaneoustumors in male Wistars. The present results clearly indicatedthe tumor inducibility of a nhrosatable amine, BHA, throughan endogenous nitrosation by feeding to rats in conjunctionwith nitrite, and provide further suggestive evidence that endogenousnitrosations of environmental nitrosatable amines can be a potentialrisk factor in human cancer development.  相似文献   
20.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司    京ICP备09084417号-23

京公网安备 11010802026262号