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91.
目的建立野艾叶中桉油精的气相色谱含量测定方法。方法采用气相色谱法测定野艾叶中桉油精的含量。色谱柱为安捷伦DB-5毛细管柱(30.00 m×0.32 mm,0.25μm),载气为99.99%高纯氮气,流速0.6 m L/min;氢气流量30 m L/min,空气流量350 m L/min,分流进样,分流比5∶1,进样量1μL;进样口温度230℃,氢火焰离子化检测器温度250℃;程序升温,起始温度60℃,以每分钟5℃升至210℃,保持5 min。结果桉油精回归方程为Y=3471.49X+13 424.5(r=0.9998),线性范围为33.02~412.70μg/m L;平均加样回收率为98.84%,相对标准偏差(RSD)为0.97%; 10份样品中,桉油精含量最高0.060%、最低0.020%。结论该法简便、准确、专属性强、重复性好,经方法学验证,本法可用于野艾叶中桉油精的含量测定,建议修订野艾叶质量标准时,将桉油精作为指标性成分进行质量控制。  相似文献   
92.
Background: Recent evidence suggests that morbid obesity is a chronic inflammatory condition that may be associated with immune dysfunction.To test this hypothesis, we investigated several leukocyte cell surface markers of chronic inflammation and followed their response to surgically-induced weight loss. Methods: 26 patients having Roux-en-Y gastric bypass (RYGBP) for morbid obesity (BMI>40) were compared to 10 normal controls (BMI<25). Relative monocyte and neutrophil frequencies and expression of the activation antigens CD11b (adhesion molecule), CD16 (Fc receptor), and CD62L (Lselectin), were evaluated by flow cytometry preoperatively and at 1, 3, 6 and 12 months after RYGBP. Cases served as their own controls but were also compared to non-obese controls. The results were statistically analyzed using Student's t-test and ANOVA for parametric values and Mann-Whitney along with Kruskal-Wallis ANOVA for nonparametric values Results: The control group had mean age 37 ± 7.6 with mean 23 ± 2.5 and no comorbidities. The mean age of the sample group was 40.36 ± 13.7 with mean BMI 52 ± 8.2. The neutrophil and monocyte relative frequencies of CD11b (monocytes and neutrophils), and CD16 (neutrophils only) were comparable to controls at baseline and did not change significantly with weight loss throughout the study period. However, a significant reduction of CD62L (Lselectin) expression was noted in monocytes and neutrophils at baseline (neutrophils 103 vs 240 gmf, p<0.001) (monocytes104 vs 246 gmf, P<0.001) when compared to normal controls. Levels of L-selectin normalized by 6 months in both monocytes and neutrophils, and by 12 months had become abnormally elevated in monocytes (monocytes 391 gmf, P=0.007); in neutrophils, there was an upward trend that did not reach significance.The expression of the LPS receptor CD14 in the study group was elevated significantly compared to controls at baseline (1129 vs 719 gmf, P=0.004); this marker appeared to return to normal by 3 months. Monocyte CD14+/CD16+ subset percentage were also elevated significantly at baseline (14.3% vs 5.25%, P <0.001), declined throughout the time period but was still significant at 1 year (8.8%, P<0.001). Eosinophil percentages were elevated at baseline (3.3% obese vs 1.8% controls, P=0.003) and remained so throughout the time period. Conclusion: Deficiencies in the immune system of morbidly obese individuals include elevated levels of eosinophils, monocyte CD14, and monocyte CD14+/CD16+ subsets, with depression of monocyte and neutrophil CD62L. These abnormal levels reverse rapidly with surgically-induced weight loss. RYGBP is not only a weight loss operation but also appears to be an immune restorative procedure.  相似文献   
93.
自体脂肪移植在颞部分层填充治疗的应用   总被引:2,自引:2,他引:2  
目的 通过对颢部的解剖分析,强调在不同区域、不同层次,多点分布移植白体脂肪,以提高其术后的成活率.方法 采用3L3M(即低压抽吸、低速离心、多点、多隧道、多层次、少量注射移植的方法)的自体脂肪移植综合技术,对颞部凹陷的56例患者按不同区域进行移植.①颞区在颞浅筋膜和皮下层填充;②额区在额肌下和皮下层填充;③在眶外侧区皮下行少量的脂肪填充.结果 56例患者,术后随访3个月至3年,颞区填充效果自然,移植脂肪吸收率低,效果满意率>85.7%.结论 通过颞部分区、分层、多点注射自体脂肪颗粒填充颞部凹陷,可以获得丰满、自然的效果.  相似文献   
94.
目的 表达和纯化CCL3L1融合蛋白,并对其免疫原性进行分析.方法 应用分子生物学技术将pGEX-4T-1-CCL3L1质粒进行酶切,收集CCL3L1片段与pET-32a(+)表达载体连接,构建pET-32a(+)-CCL3L1重组质粒,将其转化BL-21大肠埃希菌进行蛋白表达并纯化.应用酶切鉴定、SDS-PAGE及Western blot等方法确保基因片段的正确性及表达蛋白的特异性.以间接ELISA法测定BABL/c小鼠多克隆抗体滴度.结果 成功获得了高纯度的CCL3L1融合蛋白,且该蛋白为可溶性表达,以其制备的多克隆抗体滴度最高可达1:51 200.结论 获得高纯度可溶性表达的CCL3L1融合蛋白及其高效价的多克隆抗体.  相似文献   
95.
An ideal artificial substitute has good biocompatibility properties and is able to provide for rapid bone formation. Bone morphogenetic protein‐2 (BMP‐2) is considered as one of the most important growth factors for bone regeneration. In this study, a synthetic BMP‐2‐related peptide (designated P24) corresponding to residues of the knuckle epitope of BMP‐2 was introduced into a bioactive scaffold based on nano‐hydroxyapatite/collagen/poly(L ‐lactic acid) (nHAC/PLLA); its in vitro release kinetics was then measured. A 5 mm diameter cranial bone defect was created in the calvariae of 30 rats and randomly implanted with three groups of biomaterials: Group A (nHAC/PLLA alone); Group B (P24/nHAC/PLLA composite); and Group C (recombinant human BMP‐2 (rhBMP‐2)/nHAC/PLLA composite). The P24/nHAC/PLLA implants significantly stimulated bone growth similarly to the rhBMP‐2/nHAC/PLLA implants based on the radiographic and three‐dimensional CT evaluation and histological examination, thereby confirming the enhanced bone healing rate of these compounds compared with the stand‐alone nHAC/PLLA scaffold material. The osteoinductive ability of 3 mg P24 was similar to that of 1 µg rhBMP‐2. P24/nHAC/PLLA is a promising scaffold biomaterial for bone tissue regeneration. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29:1745–1752, 2011  相似文献   
96.
目的:评价新新肝康片对乙型、丙型肝炎的临床疗效。方法:对156 乙型肝炎、70 例丙型肝炎采用新新肝康片治疗,连续服药3 个月,观察每日症状、体征变化、生化指标及病毒复制指标。结果:治疗后,大部分患者临床症状减轻或消失;治疗乙型、丙型肝炎总有效率分别为82.6% 、82.5% ;治愈率分别为9.3% 、12.5 % 。结论:该药对乙型、丙型肝炎均有显著疗效,无明显的毒副作用。  相似文献   
97.
检测胆囊结石胆汁中L型细菌的研究及其意义   总被引:3,自引:0,他引:3  
目的 探讨L型细菌在胆囊结石、胆囊炎发病中的意义。方法 应用高渗培养技术对130例胆囊结石、胆囊炎及20例非胆道疾病的患者胆囊胆汁标本进行普通菌及L型菌联合培养。结果 L型菌总检出率胆囊疾病组为59.2%,对照组为5.0%;胆囊结石胆汁中,检出率最高为胆色素类结石(88.9%),其次为混合性胆石(80.0%)、胆固醇结石(54.8%)和黑色结石(50.0%);多发结石明显高于单个结石,随年龄增加,其感染检出率增高。结论 L型菌感染可能在胆囊结石、胆囊炎发生发展中有重要意义。临床上应重视其检测和治疗。  相似文献   
98.
目的探讨细胞毒T淋巴细胞相关抗原4免疫球蛋白(CTLA4-Ig)和抗CD40L单克隆抗体对异基因大鼠胰腺移植后急性排斥反应的作用及其相关机制。方法建立大鼠的胰十二指肠移植模型,供者为F344大鼠,受者为经链尿佐菌素诱导为糖尿病模型的Lewis大鼠,受者移植后分为4组,每组12只。A组:为应用生理盐水对照组;B组:应用CTLA4-Ig200μg;C组:应用抗CD40L单克隆抗体200μg;D组:联合应用CTLA4-Ig和抗CD40L单克隆抗体各200μg。各组分别于术后第2d腹腔注射相应的药物。术后1、4、7、10d分别取各组的移植胰腺,进行常规病理检测;采用逆转录聚合酶链(RT-PCR)法检测移植物白细胞介素2(IL-2)、白细胞介素4(IL-4)、白细胞介素10(IL-10)、γ干扰素(IFN-γ)的表达;术后第1、4、7、10d取受者外周血,采用流式细胞术计数T细胞亚群CD3^+、CD4^+和CD8^+;术后第4d取移植胰计数CD4^+CD25^+T细胞。结果病理检测显示:与A组相比,B、C组排斥反应明显减弱,D组几乎未发生排斥反应;B、C、D组IL-2的表达高峰延迟,且表达水平较A组有不同程度的降低,D组又较B、C组表达水平下降,差异有统计学意义;B、C、D组IFN-γ的表达水平较A组有不同程度的降低,但D组与B、C组的差异不显著;B、C组IL-4的表达水平较A组有不同程度的升高,D组较A、B、C组表达水平下降,差异有统计学意义;B、C组IL-10的表达水平较A组有不同程度的升高,D组与A组差异不显著;B、C、D组CD3^+、CD4^+和CD8^+T细胞数均相对减少,CD4^+CD25^+T细胞数有不同程度升高,与A组比较,D组的差异最为显著。结论联合应用CTLA4-Ig和抗CD40L单克隆抗体能更有效地抑制大鼠胰腺移植后排斥反应,其机制可能与Th1/Th2型细胞因子偏移及CD4^+CD25^+调节性T细胞增多等有关。  相似文献   
99.
Mutations in the X-chromosomal gene (L1CAM) for cell adhesion molecule L1 are associated with a heterogeneous group of conditions that include agenesis of the corpus callosum, hydrocephalus, spastic paraplegia, adducted thumbs and mental retardation (L1-spectrum disease, CRASH or MASA syndrome). Although L1CAM is expressed during renal development and L1cam-deficient mice have congenital malformations of the kidney and the urinary tract, L1CAM mutations have not been associated with renal anomalies in men. We report on a boy with prenatally detected hydrocephalus. After his birth, bilateral duplex kidneys and ureters, with a unilateral mega-ureter serving a hydronephrotic upper pole, as well as agenesis of the corpus callosum, adducted thumbs, spasticity, and mental retardation were recognized, fulfilling the criteria of an L1-spectrum disease. Genetic testing of the patient and his mother identified a 2 bp deletion in the invariant splice consensus sequence of intron 18 of L1CAM, predicting a largely truncated or absent protein. At the age of 9 years, 7 years after heminephrectomy, the boy has normal renal function. This observation suggests that patients with L1CAM mutations may have renal abnormalities as seen in the L1cam-deficient mouse model. L1CAM might, therefore, also be considered a possible candidate gene for renal malformations.  相似文献   
100.
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