全文获取类型
收费全文 | 276篇 |
免费 | 22篇 |
国内免费 | 1篇 |
专业分类
耳鼻咽喉 | 2篇 |
儿科学 | 2篇 |
妇产科学 | 2篇 |
基础医学 | 48篇 |
口腔科学 | 4篇 |
临床医学 | 27篇 |
内科学 | 51篇 |
皮肤病学 | 5篇 |
神经病学 | 44篇 |
特种医学 | 11篇 |
外国民族医学 | 3篇 |
外科学 | 24篇 |
综合类 | 5篇 |
预防医学 | 28篇 |
眼科学 | 2篇 |
药学 | 20篇 |
肿瘤学 | 21篇 |
出版年
2023年 | 2篇 |
2022年 | 2篇 |
2021年 | 11篇 |
2020年 | 2篇 |
2019年 | 5篇 |
2018年 | 4篇 |
2017年 | 4篇 |
2016年 | 5篇 |
2014年 | 6篇 |
2013年 | 7篇 |
2012年 | 14篇 |
2011年 | 17篇 |
2010年 | 14篇 |
2009年 | 6篇 |
2008年 | 17篇 |
2007年 | 20篇 |
2006年 | 12篇 |
2005年 | 17篇 |
2004年 | 15篇 |
2003年 | 12篇 |
2002年 | 10篇 |
2001年 | 11篇 |
2000年 | 9篇 |
1999年 | 10篇 |
1998年 | 4篇 |
1997年 | 4篇 |
1996年 | 2篇 |
1995年 | 3篇 |
1994年 | 1篇 |
1993年 | 1篇 |
1992年 | 6篇 |
1991年 | 5篇 |
1990年 | 4篇 |
1989年 | 5篇 |
1988年 | 7篇 |
1987年 | 1篇 |
1986年 | 2篇 |
1985年 | 6篇 |
1984年 | 1篇 |
1983年 | 4篇 |
1981年 | 3篇 |
1979年 | 1篇 |
1977年 | 2篇 |
1976年 | 1篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1969年 | 1篇 |
1956年 | 1篇 |
排序方式: 共有299条查询结果,搜索用时 15 毫秒
1.
The psychiatric investigation of a sample of 101 epileptic patients (65 temporal lobe epileptics (TLE) and 36 non-TLE) through various methods of evaluation, showed that only a minority of TLE with DSM-III diagnoses of Organic Brain Syndromes had severe psychopathology and manifested some personality traits. Thus, these patients seem to be differentiated from the rest of epileptics, TLE and non-TLE, who had quite "benign" psychological problems, if at all. It is quite probable that this sub-group of TLE could be the main instigators and perpetrators of the "bad image" of epileptics. The findings are discussed in relation to the pertinent literature and some hypotheses are offered for their explanation. 相似文献
2.
When Marburg virus (MBGV) nucleoprotein (NP) is expressed in insect cells, it binds to cellular RNA and forms NP-RNA complexes such as insect cell-expressed nucleoproteins from other nonsegmented negative-strand RNA viruses. Recombinant MBGV NP-RNA forms loose coils that resemble rabies virus N-RNA. MBGV NP monomers are rods that are spaced along the coil similar to the nucleoprotein monomers of the rabies virus N-RNA. High salt treatment induces tight coiling of the MBGV NP-RNA, again a characteristic observed for other nonsegmented negative-strand virus N-RNAs. Electron microscopy of fixed Marburg virus particles shows that the viral nucleocapsid has a smaller diameter than the free, recombinant NP-RNA. This difference in helical parameters could be caused by the interaction of other viral proteins with the NP-RNA. A similar but opposite phenomenon is observed for rhabdovirus nucleocapsids that are condensed by the viral matrix protein upon which they acquire a larger diameter. Finally, there appears to be an extensive and regular protein scaffold between the viral nucleocapsid and the membrane that seems not to exist in the other negative-strand RNA viruses. 相似文献
3.
Panagiota Lambrou Eleftherios Zervas Erasmia Oikonomidou Niki Papageorgiou Manos Alchanatis Mina Gaga 《Annals of allergy, asthma & immunology》2007,98(6):567-572
BACKGROUND: Asthma and rhinitis often coexist, and there is evidence to suggest that they have similar histopathologic features. OBJECTIVE: To examine whether the inflammatory infiltration in the nasal mucosa in rhinitis is affected by the presence of asthma and allergy. METHODS: Nasal mucosa biopsy samples were collected from 44 individuals: 18 with rhinitis and asthma (9 allergic and 9 nonallergic), 16 with rhinitis and no asthma (8 allergic and 8 nonallergic), and 10 nonallergic control subjects. The alkaline phosphatase-anti-alkaline phosphatase method was applied to 6-microm-thick cryostat sections using monoclonal antibodies against T cells (CD4 and CD8) and eosinophils (EG2). Slides were counted blindly, and results are expressed as cells per high-power field. RESULTS: Eosinophil counts were higher in the nasal mucosa of rhinitic patients vs controls. No differences in cellular infiltration were detected between rhinitic patients with and without asthma or between allergic and nonallergic patients. A trend toward higher CD4+ T-cell counts in the nasal mucosa of rhinitic patients was observed, whereas no differences were noted in CD8+ T-cell infiltration among the groups. CONCLUSION: Inflammatory infiltration, characterized by the presence of eosinophils and CD4+ T cells, was similar in the nasal mucosa in noninfectious rhinitis irrespective of the presence of asthma or the allergic status of the patient. 相似文献
4.
Effect of an amber mutation in the herpes simplex virus thymidine kinase gene on polypeptide synthesis and stability 总被引:14,自引:0,他引:14
KG111 is a mutant of herpes simplex virus (HSV), strain KOS, that exhibits temperature-dependent drug resistance. For example, it is almost as resistant as a thymidine kinase (tk)-deficient virus at 39 degrees, but is relatively sensitive to acyclovir at 34 degrees, Using marker transfer techniques, we have mapped the mutation conferring temperature-dependent drug resistance in KG111 to the 5' portion of the tk gene. Sequencing of this region revealed an amber mutation at codon 44, which lies between the first and second methionine codons of the tk polypeptide. This mutation is identical to that found in TK4, an HSV mutant derived from Cl 101 (L. Haarr et al., 1985, J. Virol. 56, 512-519). Analyses of immunoprecipitated tk proteins from KG111- and TK4-infected cells showed that KG111 and TK4 do not synthesize full-length tk polypeptides, but instead produce a truncated form of the protein. Small amounts of a similar truncated tk polypeptide are also produced in wild-type-infected cells and are thought to arise from initiation at a downstream AUG. The relative amounts and size of the mutant tk proteins compared with those of the wild-type are consistent with the amber mutation eliminating translation of full-length polypeptide and causing a four- to fivefold increase in the utilization of downstream AUG codons for initiation. The truncated polypeptides specified by KG111 and TK4 are less stable than the full-length polypeptide at 39 degrees, which may contribute to the conditional drug-resistant phenotype. On the other hand, the truncated polypeptides normally expressed by wild-type virus at low levels and the more highly expressed truncated tk polypeptides from a deletion mutant are relatively stable at 39 degrees. These results suggest that stability of the truncated tk polypeptide is influenced by the amount of tk present. 相似文献
5.
Comparison of the hybrid capture tube test and PCR for detection of human papillomavirus DNA in cervical specimens. 总被引:5,自引:3,他引:5 下载免费PDF全文
J U Cope A Hildesheim M H Schiffman M M Manos A T Lrincz R D Burk A G Glass C Greer J Buckland K Helgesen D R Scott M E Sherman R J Kurman K L Liaw 《Journal of clinical microbiology》1997,35(9):2262-2265
The strong association of human papillomavirus (HPV) and cervical cancer makes it important to study HPV detection methods that may play a role in cervical cancer screening. We compared two DNA methods that are commonly used for HPV research in the United States: the MY09/MY11 L1 consensus primer PCR-based test and the first-generation Hybrid Capture tube method (HCT). Laboratory assays by each method were performed with 596 cervicovaginal specimens collected from participants in a large cohort study conducted in Portland, Oreg. Included were 499 specimens from women whose cytology was normal and 97 specimens from women with squamous intraepithelial lesions (SILs). The overall HPV DNA positivity for known types was 22.5% by PCR compared to 13.6% by HCT. When the analysis was restricted to the 14 HPV types detectable by both methods, the sensitivity of HCT, with PCR used as the standard for HPV status, was higher for specimens from women with concurrent SILs (81.0%) than for specimens from women with normal cytology (46.7%). Among specimens testing positive by both methods, 97.2% of the time the two methods agreed on whether specimens were positive for cancer-associated HPV types. Both of these HPV test methods provide information that supplements the information provided by the Pap smear. The PCR method has higher analytic sensitivity than HCT in detecting HPV, but HCT may be helpful in identifying women with concurrent SILs. 相似文献
6.
Comparison of Southern blot hybridization and polymerase chain reaction methods for the detection of human papillomavirus DNA. 总被引:8,自引:2,他引:8 下载免费PDF全文
M H Schiffman H M Bauer A T Lorincz M M Manos J C Byrne A G Glass D M Cadell P M Howley 《Journal of clinical microbiology》1991,29(3):573-577
A methodologic study was performed to compare the polymerase chain reaction (PCR) and Southern blot hybridization, two commonly used testing strategies for the detection of human papillomavirus (HPV) infection. Three laboratories tested masked aliquots of exfoliated cervical cell specimens obtained from 120 women by cervicovaginal lavage. The study population included 32 women with condylomatous atypia or cervical intraepithelial neoplasia and 88 control women with no known history of cervical neoplasia. Two laboratories used PCR with different sets of consensus primers for HPV detection. The third laboratory used low-stringency Southern blot hybridization to identify all HPV types, followed by high-stringency Southern and/or dot blot hybridization to confirm specific HPV types. One of the PCR primer sets detected HPV types with a differential efficiency that was not predicted by analysis of DNA sequences or direct testing of HPV-containing plasmids. In contrast, the second PCR primer set was shown to be a much broader consensus system, detecting the same HPV types as Southern blotting, though requiring much less clinical specimen. Over 80% of women with cervical intraepithelial neoplasia or condylomatous atypia were found to be HPV infected both by Southern blotting and by the second PCR primer set. Among the control women, 11% were HPV positive by Southern blotting, while 31% were positive with the second set of primers. Most of the HPV infections found only by PCR were not due to HPV type 6, 11, 16, 18, 31, 33, or 45. These known HPV types were uncommon among normal women in the study population, even as determined by the PCR method. 相似文献
7.
Sleep apnea-related cognitive deficits and intelligence: an implication of cognitive reserve theory 总被引:3,自引:0,他引:3
Alchanatis M Zias N Deligiorgis N Amfilochiou A Dionellis G Orphanidou D 《Journal of sleep research》2005,14(1):69-75
Cognitive deficits in patients with obstructive sleep apnea syndrome (OSAS) are well demonstrated, but the pathophysiology of these deficits is still controversial, as the relationship between OSA severity and cognitive deficits is usually weak. Our study considers the possible relationship between OSA-related cognitive deficits and the overall intellectual function of OSA patients. Forty-seven OSA patients and 36 normal individuals underwent a neuropsychological battery test assessing attention and alertness. According to the resulting IQ score, patients and controls were divided into a high-intelligence group (IQ > or = 90th percentile) and a normal-intelligence group (50 < or = IQ < 90%ile). Between the two patient groups there were no significant differences noticed, regarding OSA severity or sleepiness. High-intelligence patients showed the same attention/alertness performance compared with the high-intelligence controls. On the contrary, patients with normal-intelligence showed attention/alertness decline compared with the normal-intelligence control group. The two patient groups were re-examined with the same battery test after at least 1 year of CPAP treatment. At re-examination neither patient group showed any differences regarding attention and alertness compared with the control groups. We assume that high-intelligence may have a protective effect against OSA-related cognitive decline, perhaps due to increased cognitive reserve. 相似文献
8.
Evaluation of an automated, computerized system (automicrobic system) for Enterobacteriaceae identification. 总被引:1,自引:5,他引:1 下载免费PDF全文
N M Burdash G Teti M E West E R Bannister J P Manos 《Journal of clinical microbiology》1981,13(2):331-334
The automated and computerized AutoMicrobic system (AMS; Vitek Systems, Inc., subsidiary of McDonnell Douglas, Hazelwood, Mo.) was evaluated as a means of identifying the Enterobacteriaceae. The Micro-ID system (General Diagnostics, Morris Plains, N.J.) and, when necessary, conventional tubed media were used for comparison. Identification by AMS and Micro-ID differed in only 12 of 1,528 isolates (0.8%). Disagreements occurred primarily with Enterobacter spp. Precision testing of the AMS showed only 1 of 72 tests (1.4%) deviating from the expected. The AMS was found to be an accurate and precise method for the identification of Enterobacteriaceae. 相似文献
9.
Ulcickas Yood M Quesenberry CP Guo D Wells K Shan J Sanders L Skovron ML Iloeje U Caldwell C Manos MM 《Journal of viral hepatitis》2008,15(1):28-36
The purpose of this study was to develop an algorithm for identifying patients with chronic hepatitis B virus (HBV) using automated data sources from two US health systems and evaluate the algorithm's performance by quantifying the incidence of hepatocellular carcinoma (HCC) among chronic HBV patients. To allow comparisons with estimates from automated databases that may not contain all data elements used in this algorithm, we created three definitions of chronic HBV infection and used these definitions to create three overlapping cohorts. We compared the incidence of HCC in each cohort with the incidence of HCC in a matched general population comparison cohort with no evidence of HBV. Patients who met the most stringent criteria for chronic HBV infection (based on the standard definition of 6 months of infection using repeat laboratory tests and record review) were 146 times more likely to develop HCC than matched comparison patients (adjusted hazard ratio = 146.5, 95% CI: 74.0-289.8). Those not meeting the stringent criteria, but who met the criterion of at least one positive hepatitis B surface antigen test were 30 times more likely to develop HCC than comparison patients (adjusted hazard ratio = 29.8, 95% CI: 16.5-53.6). Finally, patients who met the criterion based on at least one HBV diagnosis were 38 times more likely to develop HCC than matched comparison patients (adjusted hazard ratio = 37.8, 95% CI: 25.9-55.1). The magnitude of the relative increase in HCC risk seen using different criteria used to define HBV infection indicate that these automated data algorithms can identify patients with chronic HBV infection. 相似文献
10.