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31.
32.
ENDOTHELIN RECEPTORS IN RAT ADRENAL GLAND VISUALIZED BY QUANTITATIVE AUTORADIOGRAPHY 总被引:2,自引:0,他引:2
Masahiro Kohzuki Colin I. Johnston Siew Yeen Chai David J. Casley Fraser Rogerson Frederick A. O. Mendelsohn 《Clinical and experimental pharmacology & physiology》1989,16(4):239-242
1. The radioligand [125I]-endothelin was used to map receptors for endothelin in rat adrenal gland using in vitro autoradiography and computerized densitometry. 2. In the adrenal, a high density of binding was found in the adrenal medulla (binding affinity constant 0.18 +/- 0.11 X 10(9)M-1) and zona glomerulosa (binding affinity constant 0.18 +/- 0.07 X 10(9)M-1). Binding was low to undetectable in the zona fasciculata and zona reticularis. Unrelated peptides did not displace endothelin. 3. These results provide evidence of endothelin receptor distribution in adrenal gland and suggest that endothelin might exert multiple actions in the adrenal gland on catecholamine and aldosterone biosynthesis and secretion. 相似文献
33.
Effect of CO2 laser irradiation on experimental fracture healing: a transmission electron microscopic study 总被引:3,自引:0,他引:3
The healing of standardized fracture of rabbit radius was expedited as a result of treatment with low-power CO2 laser irradiation. Observation with transmission electron microscope revealed the following favorable effects of CO2 laser irradiation: The red blood cells were induced to disintegrate, thus promoting the absorption of the hematoma. The macrophages emerged early and increased in number so that debridement of the necrotic tissues was enhanced. The fibroblasts were more active in producing the fibrous callus. The chondrocytes were unusually active in forming bone tissues. The early and sustained appearance of osteoclasts favored the bone remodeling process. Increased capillary formation endowed the fracture healing with rich blood supply. Deposition of calcium salts took place early. 相似文献
34.
35.
Inapparent infection of hepatitis A virus 总被引:2,自引:0,他引:2
N Y Yang P H Yu Z X Mao N L Chen S A Chai J S Mao 《American journal of epidemiology》1988,127(3):599-604
To detect inapparent infection with hepatitis A virus, serial sera were collected from patients with hepatitis A and their contacts in two waterborne epidemics in China. Epidemic 1 occurred in a rural village near Hangzhou during August 1978-January 1979, and epidemic 2 took place in a rural primary school in Pinghu County in Zhejiang in April-May 1985. These sera were tested for antibodies against hepatitis A virus (anti-HAV), serum glutamic pyruvic transaminase (SGPT) activity, and icteric index. Feces also were collected in epidemic 1 to test for hepatitis A virus antigen. Both anti-HAV immunoglobulin M (IgM) and total anti-HAV were assayed in sera from "healthy persons" (symptomless persons without icterus and with normal SGPT level) who were in close contact with hepatitis A patients. In epidemic 1, among 18 "healthy persons", 12 were anti-HAV IgM positive, two were immune, and four susceptibles escaped infection. In epidemic 2, among 32 "healthy children", three were anti-HAV IgM positive, five had been infected by hepatitis A virus in the past, and 24 were not infected. These results demonstrate that inapparent infections occur along with overt and subclinical infections during epidemics of hepatitis A. The proportions of inapparent, subclinical, and overt infections were, respectively, 34.3%, 45.7%, and 20% in epidemic 1, and 25%, 50%, and 25% in epidemic 2. In addition, hepatitis A virus particles were demonstrated in the feces of all infected subjects who were examined and who included all levels of clinical response. These particles were identified with immuno-electron microscopy and enzyme-linked immunoassay. 相似文献
36.
目的 研究血清甲状腺球蛋白(Tg)、甲状腺球蛋白抗体(TgAb)对甲状腺癌根治术联合131I治疗后随访期间复发/转移的评估价值。方法 回顾性分析2018年6月—2020年6月中国贵航集团三〇二医院收治的106例分化型甲状腺癌患者的临床资料,患者均接受甲状腺癌根治术治疗,术后均采用131I进行清除残留的甲状腺组织(清甲)治疗。随访24个月,将患者分为复发转移组(21例)和未复发转移组(85例)。比较两组临床资料、131I治疗情况及血清促甲状腺激素(TSH)、Tg、TgAb。绘制受试者工作特征(ROC)曲线分析血清Tg、TgAb检测对甲状腺癌根治术联合131I治疗后复发/转移的预测价值。采取非条件一般Logistic回归模型进行多因素分析。结果 与未复发转移组比较,复发转移组原位肿瘤T4分期、手术方式为腺叶切除或近全切、残余甲状腺质量≥1 g、手术至131I治疗时间> 3个月、24 h摄131I率≤ 20%患者的占比均较高(P <0.05);复发转移组血清Tg和TgAb水平均较高(P <0.05);ROC曲线分析结果显示:血清Tg预测甲状腺癌根治术联合131I治疗后复发或转移的最佳截断值为1.674 μg/L,AUC为0.803(95% CI:0.721,0.884),敏感性为81.1%(95% CI:0.724,0.898),特异性为63.8%(95% CI:0.585,0.691);血清TgAb预测的最佳截断值为44.19 3 IU/mL,AUC为0.911(95% CI:0.859,0.963),敏感性为89.2%(95% CI:0.813,0.971),特异性为72.5%(95% CI:0.674,0.774)。非条件Logistic一般回归分析结果显示:原位肿瘤T4分期[O^R=2.916(95% CI:1.325,6.417)]、腺叶切除或近全切[O^R=3.243(95% CI:2.174,4.838)]、残余甲状腺质量≥ 10 g[O^R=1.835(95% CI:1.514,2.224)]、手术至131I治疗时间> 3个月[O^R=1.962(95% CI:1.371,2.808)]、24 h摄131I率≤ 20%[O^R=2.638(95% CI:1.219,5.709)]、血清Tg ≥ 1.674 μg/L[O^R=2.503(95% CI:1.430,4.360)]、血清TgAb≥ 44.193 IU/mL[O^R=2.944(95% CI:2.016,4.299)]可能是甲状腺癌根治术联合131I治疗后复发或转移的危险因素(P <0.05);风险因素预测模型预测甲状腺癌根治术联合131I治疗后复发/转移的ROC曲线下面积为0.961(95% CI:0.935,0.987),标准误为0.010,临界值为73.162,敏感性为91.9%(95% CI:0.863,0.957),特异性为88.2%(95% CI:0.845,0.922)。结论 甲状腺癌根治术联合131I治疗后出现复发/转移的患者血清Tg、TgAb水平明显升高,Tg、TgAb对预测复发/转移具有较好的价值,联合其他危险因素建立风险因素预测模型可进一步提高预测价值。 相似文献
37.
Three-dimensional reconstruction of adult female mouse submandibular gland secretory structures 总被引:1,自引:0,他引:1
Computer-assisted reconstructions of adult female mouse submandibular gland have been used to positionally characterize within the three-dimensional structure likely intermediates in secretory cell replacement. The locations of striated granular duct cells and granular intercalated duct cells are consistent with a role as intermediates between intercalated duct cells and granular duct cells or acinar cells, respectively. Average volumes of the two putative intermediate cell types are also consistent with this role. The reconstructions suggest that, in addition to a "streaming" mechanism for secretory cell replacement, formation of new secretory structures composed of multiple acini and second-order intercalated ducts may also contribute to the cell replacement process. 相似文献
38.
Diagnosis of Kala-Azar by Nested PCR Based on Amplification of the Leishmania Mini-Exon Gene 总被引:4,自引:0,他引:4
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Ken Katakura Shin-Ichiro Kawazu Toshimitsu Naya Koichi Nagakura Mamoru Ito Masamichi Aikawa Jing-Qi Qu Li-Ren Guan Xin-Pin Zuo Jun-Jie Chai K.-P. Chang Yoshitsugu Matsumoto 《Journal of clinical microbiology》1998,36(8):2173-2177
To diagnose visceral leishmaniasis (kala-azar), we have developed a nested PCR method based on amplification of the mini-exon gene, which is unique and tandomly repeated in the Leishmania genome. Nested PCR was sufficiently sensitive for the detection of DNA in an amount equivalent to a single Leishmania parasite or less. We examined the usefulness of this PCR method using bone marrow aspirates and buffy coat cells collected from kala-azar patients who had or had not received chemotherapy in northwest China. We obtained PCR positivity for all of the parasitologically positive bone marrow samples from the patients. Some ambiguities with the primary PCR results were eliminated by the subsequent nested PCR. The buffy coat samples from 7 of 12 patients with splenomegaly were positive by the nested PCR, although only 2 of them were positive for parasites by culture. However, buffy coat samples from nine children, whose splenomegaly has been reduced and clinically cured by antimony treatment, were all negative. Thus, this nested PCR method represents a new tool for the diagnosis of kala-azar with patient blood samples instead of bone marrow or spleen aspirates obtained by more invasive procedures. 相似文献
39.
Yongchuan Chai Yu Wang Hua Qian Bo Yang Chao Wu Jiusheng Chu Tao Yang 《American journal of medical genetics. Part A》2019,179(2):243-248
Waardenburg syndrome (WS) is a genetic disorder characterized by hearing loss and pigmentary abnormalities with variable penetrance. Though heterozygous mutations in MITF are a major cause for Waardenburg syndrome type 2 (WS2), homozygous mutations in this gene and the associated phenotype have been rarely characterized. In this study, we identified a novel p.R223H mutation in MITF in a Chinese Han family with variable WS features. Both parents carried a heterozygous p.R223H mutation. They had normal hearing, and premature greying of the hair is their only pigmentary abnormality. In contrast, their two children both carried a homozygous p.R223H mutation and had classic WS features including profound hearing loss, heterochromia irides and marked pigmentary abnormalities in hair and skin. Interestingly, the two affected children also have persistent chronic constipation since the neonatal period, symptoms suggestive of Waardenburg syndrome type 4 (WS4). Our study revealed a likely association between homozygous mutations in MITF and WS4, which implies a dosage effect for the underlying pathogenesis mechanism. 相似文献
40.
Chai Ji Dan Yao Ming‐Yan Li Wei‐Jun Chen Sheng‐Liang Lin Zheng‐Yan Zhao 《American journal of medical genetics. Part A》2020,182(9):2102-2109
To describe special facial features of children with Williams syndrome in China by using method of three‐dimensional craniofacial anthropometry. Using three‐dimensional stereo photogrammetric device, 14 craniofacial anthropometric measurements were performed and five indices were calculated in 52 children with Williams syndrome and 208 age and sex matched controls of Han Chinese ethnicity. Except intercanthal width, mouth breadth, morphological face height, nasal height‐breadth index, nasal breadth‐depth index, morphological ear index, the Williams syndrome group under 3 years old were smaller than the control group in the other 12 variables. Compared with the control group, the Williams syndrome group aged 3–5 years old had smaller biocular breadth, nasal length, nasorostral angle, bitragal breadth, ear width, morphological ear index and face depth. The Williams syndrome group aged above 6 years old had smaller biocular breadth, nasal breadth, bitragal breadth, ear width, ear length and face depth than the control group. The craniofacial variability index of the Williams syndrome group was greater than the control group. Greater variation was found among children with Williams syndrome than normal in China, specifically at eye, nose, ear and face shape, which demonstrate the usefulness of three‐dimensional stereo photogrammetric analysis in supporting accurate diagnose of the patient with Williams syndrome. 相似文献