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91.
Bone marrow-derived stromal cell monolayers pretreated with recombinant interleukin-4 (IL-4) inhibit the growth of hematopoietic cells. This was demonstrated by inhibition of fresh bone marrow-derived, IL-3- induced soft agar colonies as well as by inhibition of proliferation of IL-3-dependent cell lines and of a Friend virus-transformed erythroleukemic cell line. Pretreatment of stromal cells with IL-4 for five to seven days induced the inhibitory activity. IL-4 could then be removed before "plating" the bone marrow cells in soft agar, indicating that the inhibitory activity did not depend on the action of IL-4 on the precursors of the soft agar colonies. The inhibitory activity appears to be mediated by a soluble factor since inhibition was achieved even if the stromal cell layer was separated from the colony forming cells by an "empty" agar layer. However, supernatants of IL-4- induced stromal cell layers had no detectable inhibitory activity. The inhibitory action of the IL-4-pretreated stromal cell lines was not the result of killing of the precursor cells since it could be reversed if the agar layer containing the colony-forming cells was removed from the stromal cell layer and cultured with IL-3. Hydrocortisone (HC) blocked the inhibitory effect if added either in the IL-4 preincubation phase or during the colony formation stage, implying that HC blocked both induction of the inhibitory activity and its release or its effector function. A homogenous long-term stromal cell line could not be induced to exert the inhibitory activity; partial inhibition could be achieved with pure macrophages stimulated with IL-4 and CSF-1, suggesting that the inhibitory activity induced by IL-4 in mixed stromal cell layers may depend on a complex mechanism involving more than one cell type. Northern analysis of RNA from IL-4-induced and uninduced stromal cells indicated that IL-4 did not upregulate expression of CSF-1 or transforming growth factor-beta (TGF-beta) and only modestly increased expression of tumor necrosis factor, suggesting that these cytokines were not responsible for the inhibitory activity. The capacity of IL-4 to induce inhibitory activity in stromal cell layers suggests that IL-4 may play a role in the regulation of hematopoiesis. 相似文献
92.
小藤铃儿草的生物碱成分 总被引:1,自引:0,他引:1
自小藤铃儿草Dactylicapnos torulosa(Hook.f ct Thomas.)Hutchins中分得六个单体,通过UV,IR,MS,~1HNMR和~(13)CNMR解析,鉴定了四个,其中一个为新化合物,命名为紫金龙碱(zijinlongine,Ⅰ),其他三个为已知化合物:氯化1-甲氧基小檗碱(1-methoxylberberium chloride,Ⅱ),氯化三乙基苯胺(triethylphcnylamium chloride,Ⅲ)和异紫堇定(isocorydine,Ⅳ)。Ⅱ和Ⅲ系首次从植物中得到。 相似文献
93.
T3N0 rectal cancer: Results following sharp mesorectal excision and no adjuvant therapy 总被引:6,自引:0,他引:6
Nipun B. Merchant M.D. Jose G. Guillem M.D. M.P.H. Phillip B. Paty M.D. Warren E. Enker M.D. Bruce D. Minsky M.D. Stuart H. Q. Quan M.D. Douglas Wong M.D. Alfred M. Cohen M.D. 《Journal of gastrointestinal surgery》1999,3(6):642-647
Adjuvant chemoradiation therapy following resection of T3N0 rectal cancer is recommended in order to reduce the incidence
of local recurrence and improve survival. However, recent experience with rectal cancer resection utilizing sharp dissection
and total mesorectal excision has resulted in a reduction in local recurrence rates to as low as 5% without adjuvant treatment.
The purpose of this study was to determine if rectal cancer resection utilizing sharp mesorectal excision alone is adequate
treatment for local control of T3N0 rectal cancer. Between July 1986 and December 1993, 95 patients with T3N0M0 rectal cancer
underwent resection with sharp mesorectal excision and did not receive any adjuvant therapy. Various prognostic factors were
analyzed for their association with local recurrence and survival. Seventy-nine patients had a low anterior resection, 10
of whom had a coloanal anastomosis, and 16 had an abdominoperineal resection. The median follow-up was 53.3 months. Six patients
had local recurrence, 12 had distant recurrence, and three had local and distant recurrences. The overall local recurrence
rate was 9% crude and 12% 5-year actuarial. The overall crude recurrence rate was 22%. The 5-year disease-specific survival
rate was 86.6% with an overall survival of 75%. Postoperative complications occurred in 18 patients (19%). Five patients (6%)
had a documented anastomotic leak. Perioperative mortality was 3%. No technical factors, including type of resection (low
anterior vs. abdominoperineal), location of tumor, or extent of resection margin, were significant for determining local recurrence.
The only histopathologic marker significant for determining local recurrence was lymphatic invasion (P <0.04). Sharp mesorectal excision with low anterior resection or abdominoperineal resection for T3N0M0 rectal cancer results
in a local recurrence rate of less than 10% without the use of adjuvant therapy. Therefore, in select patients with T3N0M0
rectal cancer, the standard use of adjuvant therapy for local control may not be justified.
Presented at the Thirty-Ninth Annual Meeting of The Society of Surgery for the Alimentary Tract, New Orleans, La., May 17–20,
1998. 相似文献
94.
95.
96.
广州地区呼吸道疾病患儿16种常见变应原检测分析 总被引:1,自引:0,他引:1
目的 了解广州地区呼吸道疾病患儿对16种常见变应原的过敏情况,同时探讨不同年龄组之间的变应原阳性率差异,并比较致敏程度.方法 选择2007年8月至2008年3月广州医学院第一附属医院呼吸科门诊和儿科门诊初诊为支气管哮喘、过敏性鼻炎、呼吸道感染等患儿320例为研究对象,其中婴幼儿组(≤3岁)214例,儿童组(>3岁)106例.采用德国FOOKE ALLERG-O-LIQ-SYSTEM变应原检测系统,通过免疫捕获法检测血清中常见的16种变应原特异性免疫球蛋白E(SIgE)抗体.结果 在所有患儿中,其中261例(81.56%)SIgE呈阳性.59例(18.44%)呈阴性.16种变应原SIgE阳性率为屋尘螨(36.88%)、粉尘螨(35.31%)、热带螨(24.06%)、狗毛(6.56%)、猫毛(8.75%)、德国小蠊(16.56%)、蜜蜂毒素(0.94%)、屋尘(45.63%)、全蛋(45.94%)、牛奶(46.25%)、小麦面粉(6.88%)、玉米粉(1.25%)、花生(9.06%)、大豆(5.94%)、螃蟹(2.81%)、虾(4.38%).婴幼儿组SIgE的阳性率为81.78%,以食物性变应原(牛奶、全蛋)为主;儿童组的阳性率为81.13%,以吸人性变应原(尘螨)为主(X2=0.02,P=0.89).儿童组尘螨的过敏阳性率均高于婴幼儿组(P<0.05),且儿童组屋尘螨和粉尘螨的过敏程度多在3级以上.婴幼儿组各级阳性率比较平均.两组对热带螨的过敏程度均较低,多在3级以下.婴幼儿组牛奶和全蛋过敏阳性率高于儿童组(P<0.05),两组的过敏程度均在3级以下.结论 儿童组与婴幼儿组对常见变应原的总阳性率差异无统计学意义,只是对不同变应原阳性率及过敏程度的差异.儿童组主要是对吸人性变应原产生过敏,婴幼儿组主要是对食物性变应原产生过敏,应以不同年龄段来分析儿童变应原检测结果. 相似文献
97.
健康人心室复极的昼夜变化研究 总被引:1,自引:1,他引:0
目的 探讨健康人心室复极的昼夜变化规律. 方法 对34例健康体检者的24h动态心电图进行回顾性分析.测定其心率、Q-T间期、QRS波群起点至T波波峰的时间(Q-Tp间期).计算T波波峰至终点的时间(Tp-e时间)、心率校正的Q-T间期(Q-Tc间期)和Tp-e时间(Tp-ec时间)、Tp-e/Q-T值,并比较一天中8个等分时间段的上述参数. 结果 Q-T间期和Tp-e时间呈日间短、凌晨及午夜长的昼夜节律变化,各时间段差异有统计学意义(P<0.01或0.05);Q-T间期与心率呈高度负相关(r=-01796,P<0.01).而Tp-e时间与心率呈低度负相关(r=-01267,P<0.01);各时间段Q-Tc间期接近,而Tp-ec时间呈07:00~09:00最高、10:00~12:00次之、01:00~03:00最低的昼夜节律变化,各时间段差异有统计学意义(P<0.05),Tp-e/Q-T值昼夜变化节律与Tp-ec时间相近.结论 反映心室复极跨壁离散度的Tp-e时间除受心率影响外,尚受昼夜节律的影响. 相似文献
98.
99.
细胞因子在慢性肝衰竭合并全身炎症反应综合征病例中的意义 总被引:1,自引:0,他引:1
目的探讨TNF-α、IFN-γ、LPS、IL-10、IL-12、IL-18在慢性肝衰竭合并全身炎症反应综合征(SIRS)中的意义。方法运用双抗体夹心酶联免疫吸附法检测正常人、一般肝炎患者、慢性肝衰竭组的TNF-α、IFN-γ、LPS、IL-10、IL-12、IL-18。结果自正常对照组到一般肝炎组、慢性肝衰竭非SIRS组、慢性肝衰竭SIRS组,血清中TNF-α、LPS、IL-12及IL-18水平依次升高,IL-10分子水平依次减低,且各组间比较均具有显著性差异。结论TNF-α、LPS、IL-10、IL-12、IL-18水平可以反应出乙型肝炎患者的肝脏损伤程度和疾病严重程度,可能在慢性肝衰竭合并SIRS的发病过程中起到相当重要的作用。 相似文献
100.
汞中毒肾脏损害的早期监测指标筛选 总被引:7,自引:0,他引:7
目的筛选汞作业者肾脏损害的早期监测指标并探讨其临床意义。方法85例汞作业者分为汞接触正常/观察对象组、汞中毒组,并以无汞接触史的65例健康成人作为对照组。分别进行临床体检并测定尿汞(HgU)、血肌酐(B-Cr)、尿肌酐(U-Cr)、血尿素氮(BUN)、尿-N-乙酰-β-D葡萄糖苷酶(NAG)、尿β2-微球蛋白(β2-MG)、尿α1-微球蛋白(α1-MG)和尿视黄醇结合蛋白(RBP),排除肾病史和患有肾脏疾病患者后对结果进行分析。结果汞作业者HgU、B-Cr、NAG、β2-MG、α1-MG和RBP均高于对照组(P<0.01);汞作业正常/观察对象组的β2-MG、NAG和RBP水平高于对照组(P<0.01),α1-MG有升高趋势,但与对照组相比差异无统计学意义,传统肾脏损害指标B-Cr和BUN与对照组相比差异亦无统计学意义。结论长期汞接触可造成肾功能损害,尿NAG、β2-MG、α1-MG、RBP可作为汞作业者肾脏损害的早期监测指标。 相似文献