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511.
人工髓核假体置入治疗腰椎间盘突出症的疗效分析   总被引:2,自引:0,他引:2  
目的:观察已在临床初步开展起来的人工髓核置换术治疗腰椎间盘突出症的中、远期临床疗效及并发症,分析其对策。 方法:纳入2002-02/2004-08南方医科大学附属南方医院脊柱骨病外科采用单枚人工髓核假体置换术治疗单节段腰椎间盘突出症患者98例,获得24~48个月随访患者75例,按平均随访时间达24,36,48个月,分为24个月组(n=30),36个月组(n=23),48个月组(n=22)。选同期采用单纯椎间盘髓核摘除术患者30例作为对照组,评估各组术后临床疗效,主观症状采用Oswestry功能障碍指数问卷表(0%表示正常,越接近100%则功能障碍越严重)和Prolo功能评分表(小于或等于5分为差,6~7分为中等,8~10为优)评价,分析术后影像学检查并测量手术节段活动度和椎间隙高度变化情况,同时观察假体位置情况,腰椎MRI观察假体位置和软骨终板的信号变化情况。腰椎活动度=(腰椎中立角度-前屈角度)+(后伸角度-腰椎中立角度)=后伸角度-前屈角度;为消除X射线放大率的影响,椎间隙高度变化情况采用病变椎间隙后缘高度与上位椎体中部矢状径的比值表示。 结果:75例获得24~48个月随访者,全部进入结果分析。①48个月组2例、36个月组1例发生假体脱出,二次手术取出。其余患者术后临床症状均明显缓解,疼痛消失。②24,36,48个月组及对照组术后末次Oswestry功能障碍指数均较术前降低,差异有显著性意义(14.2%,52.1%;15.5%,55.2%;15.1%,53.6%;15.5%,51.5%;P〈0.05)。③24,36,48个月组及对照组术后末次Prolo能评分均较术前升高,差异有显著性意义(8.5,4.6分;8.6,4.5分;8.7,4.3分;8.4,4.2分;P〈0.05)。④24,36,48个月组同期手术节段腰椎活动度均高于对照组,差异有显著意义(P〈0.05)。⑤24个月组手术节段椎间高度较术前降低约4%、36个月组降低约12%、48个月组降低约18%、对照组较术前降低约25%,各组术前和术后椎间隙高度比值比较,差异具有显著性意义(P〈0.05)。⑥主要并发症:早期出现术后一过性腰痛24例,假体脱出3例。中、远期发现假体下沉32例,软骨终板损伤39例。 结论:单枚人工髓核假体置换治疗腰椎间盘突出症中、远期随访临床疗效肯定,但存在较严重并发症,应慎重开展此项手术。  相似文献   
512.
A retrospective study at our hospital determined the race or ethnicity of patients seen in an 8-year period who had formed antibodies to Duffy antigens. During that time, 9876 serologic investigations had been performed as a result of a positive direct or indirect antiglobulin test. Among these samples, sera from 45 previously transfused or pregnant patients contained anti-Fya and two contained anti-Fy3. Twenty-nine of the sera that contained anti-Fya (62%) were from blacks, 12 (25%) were from whites, and 6 (13%) were from Hispanics. Both examples of anti-Fy3 were made by black patients. Red cells (RBCs) from 21 of the black patients were Fy(a-b-), those from 7 were Fy(a-b+), and those from 1 could not be phenotyped. RBCs from 17 of the non-black patients were Fy(a-b+) and those from 1 could not be phenotyped. The population of transfused patients evaluated in this study was 47 percent black, 29 percent white, and 24 percent Hispanic. Calculations based on an expected Fy(a-) frequency of 88 percent in blacks, 33 percent in whites, and 20 percent in Hispanics predict that the racial makeup of the Fy(a-) population at our hospital would be 73 percent black, 18 percent white, and 9 percent Hispanic, which is not significantly different (p = 0.25) from the racial makeup of the patients forming anti-Fya and -Fy3. These data indicate that blacks make antibodies to Duffy antigens as frequently as non-blacks.  相似文献   
513.
514.
OBJECTIVE: This report evaluates and compares individual oral lesions and combinations of lesions in predicting progression-free survival in a seroprevalent cohort of men and women with HIV infection. DESIGN: This was a prospective study of HIV-infected patients, initially AIDS-free, followed for approximately 30 months. SETTING: Patients were volunteers examined at an academic medical center and at an inner-city hospital in New York. Participants identified themselves as homosexual men or as injection drug users (IDU).OUTCOME MEASURES: The primary outcome being assessed is time from a baseline oral examination until the development of an AIDS-defining condition or death from any cause within 12 months of the last study visit. Correlation is measured by relative risk (RR).RESULTS: While oral lesions were not predictive of progression among subjects with CD4s=200, they were highly predictive of progression among those with CD4<200.For subjects with CD4<200, the only individual lesion that was significantly associated with progression-free survival was oral candidiasis (RR=4.12, P= 0.009).Positivity for one or more lesions in a set demonstrated greater prognostic value among those with CD4<200, with RR's of 6.03 (P= 0.018) for the set consisting of oral candidiasis, hairy leukoplakia, and necrotizing ulcerative gingivitis (NUG), and 8.77 (P= 0.036) for the set consisting of the above lesions plus linear gingival erythema (LGE).Analysis by cohort suggested that the improvement in correlation was stronger in homosexual men than in IDU, but this question could not be resolved conclusively with these data. CONCLUSIONS: Lesion sets might be better prognosti-cators of progression-free survival than individual lesions among HIV-infected subjects with CD4<200.Prognostic value of the core lesion set (oral candidiasis and hairy leukoplakia) was enhanced by the addition of other lesions (NUG and LGE) not usually included in HIV staging systems. These results suggest that staging systems for HIV might be improved by the inclusion of other, survival-related oral lesions.  相似文献   
515.
Neutrophils are the most abundant circulating leukocyte and are crucial to the initial innate immune response to infection. One of their key pathogen-eliminating mechanisms is phagocytosis, the process of particle engulfment into a vacuole-like structure called the phagosome. The antimicrobial activity of the phagocytic process results from a collaboration of multiple systems and mechanisms within this organelle, where a complex interplay of ion fluxes, pH, reactive oxygen species, and antimicrobial proteins creates a dynamic antimicrobial environment. This complexity, combined with the difficulties of studying neutrophils ex vivo, has led to gaps in our knowledge of how the neutrophil phagosome optimizes pathogen killing. In particular, controversy has arisen regarding the relative contribution and integration of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase-derived antimicrobial agents and granule-delivered antimicrobial proteins. Clinical syndromes arising from dysfunction in these systems in humans allow useful insight into these mechanisms, but their redundancy and synergy add to the complexity. In this article, we review the current knowledge regarding the formation and function of the neutrophil phagosome, examine new insights into the phagosomal environment that have been permitted by technological advances in recent years, and discuss aspects of the phagocytic process that are still under debate.  相似文献   
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