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1.
We established a murine monoclonal antibody (K1H8) to human papillomavirus (HPV) using alkaline-disrupted virions of HPV type 1 (HPV-1) as the immunogen. K1H8 recognized a 57 kD capsid protein of HPV-1 and detected the antigen in paraffin sections of formalin-fixed tissue. With K1H8, we examined immunohistochemically 68 biopsy specimens obtained from the female genital tract. The specimens were histologically condyloma acuminatum or koilocytotic lesions with or without dysplasia and each specimen was found to harbour a single type of genital HPV, such as types 6, 11, 16, 18, 31, 33, 42, 51, 52, 56, and 58, by Southern blot hybridization analysis. The antigen was localized in the nuclei and occasionally in the cytoplasm of squamous cells showing koilocytotic changes. Eighty-four per cent of the specimens (57 cases) showed positivity for the antigen, indicating that K1H8 is a broadly-reactive antibody to various genital HPVs. The results suggest that benign mucosal lesions of the female genital tract are more frequently associated with viral production and are a potential source of transmission.  相似文献   
2.
CD56 is immunohistochemically detectable in virtually all small cell carcinomas on frozen sections. The authors retrospectively tested the usefulness of the monoclonal antibody 123C3 against CD56 to differentiate pulmonary and extrapulmonary small cell carcinomas from nonneuroendocrine non—small cell carcinomas by paraffin-section immunohistochemistry after antigen retrieval. The study included 70 small cell carcinomas and 344 primary and metastatic nonneuroendocrine carcinomas of various primary sites. The staining results were compared with specific neuroendocrine markers (CD57, Chromogranin A, Synaptophysin). The monoclonal antibody 123C3 diffusely stained most small cell carcinomas with a strong membranous pattern (sensitivity: 0.99). The staining intensity was not diminished in areas with crush artifacts or after decalcification. The neuroendocrine markers had a combined sensitivity of only 0. 44 for small cell carcinomas. With regard to nonneuroendocrine carcinomas, the 123C3 antibody stained 7 of 28 ovarian carcinomas, 6 of 30 renal cell carcinomas, 2 of 10 endometrial carcinomas, two of three nonneuroendocrine large cell carcinomas of the lung, 1 of 38 adenocarcinomas, and 4 of 52 squamous cell carcinomas of the lung. Urothelial carcinomas, hepatocellular carcinomas, squamous carcinomas of the head/neck and cervix uteri, as well as adenocarcinomas of the breast, stomach, colon, pancreas, and prostate, showed no immunoreactivity for CD56. The specificities of 123C3 and the combined neuroendocrine markers for small cell carcinomas were 0. 94 and 0. 95, respectively. The authors conclude that monoclonal antibody 123C3 might be useful for the immunohistochemical differentiation of small cell carcinomas from nonneuroendocrine carcinomas on paraffin sections, especially in small and crushed biopsy specimens.  相似文献   
3.
Tissue microarrays have been created from 326 lung tumours, including 173 squamous cell carcinomas (SCCs) and 132 adenocarcinomas (ADs). In order to evaluate the usefulness of this microarray series, the expression of p53, p16, and Rb proteins was compared by immunohistochemistry on both the tissue microarrays and the corresponding whole sections for all 326 tumours. The presence of replicate punches improved both the yield and the concordance of data relative to the whole section results, so that the consensus score from the replicates agreed with the whole section result in more than 90% of informative tumours. The large number of tumours in this series also allowed significant differences in protein expression patterns to be detected between SCC and AD, the major subtypes of non-small cell lung carcinoma (NSCLC). SCC had higher levels of p53 staining (67% vs 52% in AD) and substantially increased p16 loss (SCC 75%, AD 53%) combined with greater retention of pRB expression (SCC 86% vs 67% in AD). The strong inverse correlation between p16 and pRB seen in SCC was essentially absent in AD. This study represents the largest single immunohistochemical survey of protein expression for p53, p16, and RB in NSCLCs.  相似文献   
4.
The genetic diagnosis of Gaucher disease by molecular methods is complicated by the existence of a highly homologous transcribed pseudogene (96% identity) that is found in close proximity to the true gene on chromosome 1q21. In addition, the pseudogene sequence can mimic disease-causing mutations in the true gene. Selective polymerase chain reaction (PCR) amplification of the true gene can be accomplished in extracted DNA from fresh-frozen samples by designing oligonucleotide primers to hybridize to defined regions that are not present in the pseudogene. This standard molecular approach, which entails amplification of relatively long segments of intact DNA, is not feasible in archival, paraffin-embedded, solid-tissue specimens in which the negative effects of chemical fixation result in DNA strand scission and breakdown of nucleic acid. A novel approach, specifically created for use with archival, fixative-treated tissue specimens, was developed for detection and characterization of common mutations of Gaucher disease. Three separate robust PCR reactions were formulated, 2 for selective amplification of portions of only the true gene exons 2 and 9, with a third reaction targeting exon 10, wherein both the true and pseudogene were coamplified. In the latter, DNA sequencing was used to determine the presence of true and pseudogene allele content in addition to identification of base sequence alterations. This method, requiring a single, 4-microm-thick histologic section, was successfully applied to archival paraffin block tissue specimens that had been in storage for up to 75 years. It was capable of accurately genotyping common Gaucher disease mutations as well as discovering a novel mutation and genetic polymorphism. We recommend our approach when only fixative-treated tis sue is available for molecular genotyping.  相似文献   
5.
RNA was extracted from tissues processed by a new fixation and paraffin-embedding method (the AMeX method) and examined by Northern blot analysis and slot-blot analysis. The RNA extraction method for AMeX-processed tissue sections after the deparaffinization step was the same as that for fresh materials. The total amount of cellular RNA extracted from AMeX-processed mouse liver tissue was slightly less than that extracted from fresh tissue. In tissues of malignant lymphoma, the total amount of cellular RNA extracted from 25 sections each 20 microns thick was about 1.6-1.8 micrograms/mm2, regardless of the histological subtype and period of storage. The extracted RNA was moderately degraded, and usually could not be used for Northern blot hybridization analysis. The intensity of ethidium bromide staining and the hybridization signals of RNA extracted from AMeX-processed tissues were usually reduced in comparison with RNA from fresh material, but specific signals could be detected by slot-blot hybridization analysis. We have demonstrated previously that the AMeX method preserves high-molecular-weight DNA and various antigens. Since the present study showed that information on mRNA can be obtained from AMeX-processed tissue, the versatility and usefulness of this method were further proven.  相似文献   
6.
考察了柴油对流动改进剂的感受性与柴油正构烷烃含量、正构烷烃分布等因素的关系。流动改进剂的作用与正构烷烃含量有最佳匹配点。柴油中正构烷烃的平均碳数减少,冷滤点越低。柴油中正构烷烃的分布与流动改进剂的熔点匹配时,改进剂的效果最好。由此进一步分析了柴油流动改进剂的作用机理。  相似文献   
7.
毛节缬草的解剖构造观察   总被引:2,自引:1,他引:2  
目的:观察黑龙江省毛节缬草的解剖构造,明确其鉴别特征,为进一步制定缬草的质量标准及开发利用提供科学依据。方法:石蜡切片技术。结果:明确了黑龙江省毛节缬草的根、根茎、茎和叶的显微特征。结论:这些显微特征可作为毛节缬草的鉴别手段。  相似文献   
8.
9.
Purpose.?To compare treating patients with symptomatic hand osteoarthritis (OA) with paraffin baths only (PO) (100% wax) or paraffin baths 80% wax with 20% topical analgesic (PTA).

Methods.?Subjects met criteria of the American College of Rheumatology for classifying symptomatic hand OA and had a Dreiser's index score >5 points. Current and average pain at rest and with movement was assessed with visual analogue scales. Hand function was assessed by the functional index for hand OA (FIHOA).

Results.?Both groups had a significant reduction in their ‘current’ pain 15?min after the first and twelfth treatments compared to pre-treatment but there was no difference between groups (t?=?0.10, p?>?0.05). The PTA group had greater improvement over the 12 treatment sessions for their pain at rest (t?=?2.92, p?<?0.05) and with movement (t?=?4.73, p?<?0.05) than the PO group. The PTA group also showed greater improvement in their FIHOA following 12 treatments than the PO group (t?=?3.52, p?<?0.05).

Conclusion.?Our results indicate that the addition of a topical analgesic to paraffin produced significantly greater pain relief at rest and during movement than paraffin baths alone after 12 treatments. Additionally, the PTA group experienced greater improved hand function.  相似文献   
10.
目的:寻找真菌性角膜炎组织切片快速、准确、方便操作的特殊染色方式。

方法:采用经真菌培养均为阳性的真菌性角膜炎患者的角膜标本38例,常规固定脱水透明浸蜡,进行4μm石蜡切片,脱蜡至水,选用异硫氰酸荧光素(FITC)荧光法和过碘酸雪夫氏染色法(PAS)进行染色对比。

结果:异硫氰酸荧光素法检测阳性率为97.4%(37/38),过碘酸雪夫氏染色法检测阳性率为86.8%(33/38)。结果比较有统计学差异(P<0.001)。

结论:异硫氰酸荧光素法镜检真菌性角膜炎优于过碘酸雪夫氏染色法镜检。  相似文献   

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