全文获取类型
收费全文 | 15245篇 |
免费 | 1408篇 |
国内免费 | 24篇 |
专业分类
耳鼻咽喉 | 162篇 |
儿科学 | 556篇 |
妇产科学 | 410篇 |
基础医学 | 2209篇 |
口腔科学 | 273篇 |
临床医学 | 1897篇 |
内科学 | 2863篇 |
皮肤病学 | 194篇 |
神经病学 | 1445篇 |
特种医学 | 365篇 |
外科学 | 1953篇 |
综合类 | 199篇 |
一般理论 | 17篇 |
预防医学 | 1812篇 |
眼科学 | 245篇 |
药学 | 885篇 |
中国医学 | 9篇 |
肿瘤学 | 1183篇 |
出版年
2023年 | 115篇 |
2022年 | 147篇 |
2021年 | 428篇 |
2020年 | 268篇 |
2019年 | 416篇 |
2018年 | 480篇 |
2017年 | 330篇 |
2016年 | 352篇 |
2015年 | 407篇 |
2014年 | 530篇 |
2013年 | 745篇 |
2012年 | 1052篇 |
2011年 | 1070篇 |
2010年 | 560篇 |
2009年 | 471篇 |
2008年 | 832篇 |
2007年 | 854篇 |
2006年 | 775篇 |
2005年 | 750篇 |
2004年 | 604篇 |
2003年 | 584篇 |
2002年 | 524篇 |
2001年 | 298篇 |
2000年 | 340篇 |
1999年 | 276篇 |
1998年 | 160篇 |
1997年 | 129篇 |
1996年 | 111篇 |
1995年 | 105篇 |
1994年 | 101篇 |
1993年 | 102篇 |
1992年 | 210篇 |
1991年 | 205篇 |
1990年 | 163篇 |
1989年 | 181篇 |
1988年 | 171篇 |
1987年 | 188篇 |
1986年 | 148篇 |
1985年 | 162篇 |
1984年 | 119篇 |
1983年 | 87篇 |
1982年 | 67篇 |
1981年 | 79篇 |
1980年 | 66篇 |
1979年 | 102篇 |
1978年 | 93篇 |
1976年 | 64篇 |
1973年 | 66篇 |
1972年 | 60篇 |
1971年 | 62篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Enzyme Immunoassay Detecting Teichoic and Lipoteichoic Acids versus Cerebrospinal Fluid Culture and Latex Agglutination for Diagnosis of Streptococcus pneumoniae Meningitis
下载免费PDF全文
![点击此处可从《Journal of clinical microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Kristin Stuertz Imke Merx Helmut Eiffert Erich Schmutzhard Michael Mder Roland Nau 《Journal of clinical microbiology》1998,36(8):2346-2348
A newly developed enzyme immunoassay (EIA) was used to detect the presence of pneumococcal teichoic and lipoteichoic acids in cerebrospinal fluid (CSF) from patients with Streptococcus pneumoniae meningitis who were being treated with antibiotics. All initial CSF samples, which on culture grew S. pneumoniae, were positive in the EIA. A total of 14 subsequent culture-negative samples gave clear signals in the EIA up to day 15 after the onset of antibiotic treatment. For 11 CSF specimens, culture, microscopy, and latex agglutination were negative while the EIA detected pneumococcal antigens. The EIA did not react either with CSF of patients with meningitis caused by bacteria other than S. pneumoniae or by viral pathogens. In conclusion, this EIA can be a valuable tool for the diagnosis of S. pneumoniae meningitis from CSF samples in cases in which prior antimicrobial therapy minimizes the usefulness of culture or other antigen detection tests. 相似文献
102.
A reciprocal translocation is described, t(4;21)(q27;p11), which occurs in a balanced carrier mother and her Down's syndrome child, 47,XX,t(4q-;21p+),+21. A review is presented of Down's syndrome associated with reciprocal translations involving chromosome No. 21. 相似文献
103.
Routine papillomavirus antigen staining of cervical punch biopsy specimens. 总被引:1,自引:1,他引:1
下载免费PDF全文
![点击此处可从《Journal of clinical pathology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
Immunocytochemical staining for papillomavirus antigen was carried out on 1147 consecutive cervical punch biopsy specimens over 12 months. Of 876 cases with cervical intraepithelial neoplasia (CIN) 351, were antigen positive and of 49 cases with histological evidence of human papillomavirus (HPV) infection but no CIN, 14 were positive. There were 204 cases reported to be normal on routine histological examination and 12 cases reported to show features suggestive but not diagnostic of HPV infection. Of the normal group, 24 (12%) were antigen positive and of the equivocal group, two were positive. In 122 of the normal or equivocal groups cytological examination was repeated at the time of colposcopy, and dyskaryosis was reported in 36. In only four cases was disease shown by HPV antigen staining when there was no diagnostic histological or cytological abnormality. HPV antigen staining assists in the recognition of the range of histological changes associated with productive HPV infection but is an insensitive test and has only limited value in supplementing histological and cytological examinations as a diagnostic aid in routine colposcopic pathology. 相似文献
104.
Shimp KL Bhatnagar KP Bonar CJ Smith TD 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2003,274(1):862-869
Ecological explanations have been put forward to account for the precocious or delayed development of patency in ducts leading to the vomeronasal organ (VNO) in certain mammals. Perinatal function may be related, in part, to the patency or fusion of the vomeronasal and nasopalatine (NPD) ducts. However, few studies have focused on NPD development in primates, which generally have a prolonged period of dependence during infancy. In this study we examined 24 prenatal primates and 13 neonatal primates, and a comparative sample of fetal mice and insectivores. In embryonic and early fetal Microcebus murinus, the NPD was completely fused, whereas in fetuses of later stages the duct was partially fused or completely patent. M. myoxinus of all stages demonstrated some degree of NPD fusion. In all other prenatal primates, the NPD was fused to some extent. Four prenatal insectivores (Tenrec ecaudatus) showed some degree of NPD fusion. In Mus musculus at 19 days gestation, the NPD was patent, although the anatomically separate VNO duct was fused. T. ecaudatus and most of the neonatal primates revealed complete NPD patency. An exception was Saguinus geoffroyi, which exhibited fusion of the NPD near the VNO opening. These observations may relate to differences in perinatal VNO function. The differences noted in our study suggest that M. murinus and M. myoxinus may differ in perinatal VNO functionality and perhaps in related behavior. Observations of neonatal primates suggest that NPD patency may be relatively common at birth and could serve other purposes in addition to being an access route for VNO stimuli. 相似文献
105.
Intranasal vaccination induces protective immunity against intranasal infection with virulent Francisella tularensis biovar A
下载免费PDF全文
![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
The inhalation of Francisella tularensis biovar A causes pneumonic tularemia associated with high morbidity and mortality rates in humans. Exposure to F. tularensis usually occurs by accident, but there is increasing awareness that F. tularensis may be deliberately released in an act of bioterrorism or war. The development of a vaccine against pneumonic tularemia has been limited by a lack of information regarding the mechanisms required to protect against this disease. Vaccine models for F. tularensis in inbred mice would facilitate investigations of the protective mechanisms and significantly enhance vaccine development. Intranasal vaccination with the attenuated live vaccine strain (LVS) of F. tularensis reproducibly protected BALB/c mice, but not C57BL/6 mice, against intranasal and subcutaneous challenges with a virulent clinical isolate of F. tularensis biovar A (NMFTA1). The resistance of LVS-vaccinated BALB/c mice to intranasal NMFTA1 challenge was increased 100-fold by boosting with live NMFTA1 but not with LVS. The protective response was specific for F. tularensis and required both CD4 and CD8 T cells. The vaccinated mice appeared outwardly healthy for more than 2 months after NMFTA1 challenge, even though NMFTA1 was recovered from more than half of the vaccinated mice. These results show that intranasal vaccination induces immunity that protects BALB/c mice from intranasal infection by F. tularensis biovar A. 相似文献
106.
DNA fingerprinting of isolates of Staphylococcus aureus from newborns and their contacts 总被引:2,自引:5,他引:2
Y Tveten B E Kristiansen E Ask A Jenkins T Hofstad 《Journal of clinical microbiology》1991,29(6):1100-1105
During a study on the epidemiology of Staphylococcus aureus colonization in newborns, mothers, and hospital staff, S. aureus was isolated from 536 of 1,945 specimens. Ninety-three isolates of S. aureus from the three groups of individuals were included in a study to evaluate the potential of DNA fingerprinting for strain differentiation. The 93 isolates were also phage typed and their plasmid profiles were analyzed. Cleavage of DNA with BamHI resulted in 13 different DNA restriction endonuclease band patterns (DNA REBPs), one of which consisted of eight isolates whose DNA was not cleaved with BamHI. The DNAs from these eight isolates were easily cleaved with HindIII. The different DNA REBPs were stable both during in vitro and in vivo growth and allowed strain differentiation within phage groups or types. We could not show any strong association between DNA REBP classes, phage types or groups, and plasmid profiles. Of the 93 isolates, 27 (29.0%) could not be phage typed and 12 (12.9%) lacked plasmids. We therefore conclude that DNA fingerprinting is a powerful tool, in addition to phage typing and plasmid profile analysis, for strain differentiation of S. aureus. 相似文献
107.
Kaitlyn Walsh Teaghan A.M. Pryor Kristin A. Reynolds John R. Walker 《Patient education and counseling》2019,102(1):99-105
Objective
The purpose of this study was to evaluate websites providing information on treatment for depression to the public, and to evaluate changes in the quality of website information over time.Methods
Websites (N?=?25) addressing depression treatment were identified through the use of the Google search engine and by suggestions from healthcare professionals. Each website was evaluated based on the extent to which it addressed content areas deemed important by the public identified in previous research, overall quality as determined by the DISCERN, and reading level.Results
Overall, the quality of depression websites varied greatly. The majority of websites did not adequately answer the public’s questions about treatment options, and presented higher quality information in the area of pharmacological treatments as compared to other treatment options. An average reading level of 10.0 was found across websites. Upon re-evaluation, only 14 of 25 websites added new content, and the majority of websites did not improve in their overall website quality (as measured by the DISCERN).Conclusion and Practice Implications
Websites could be improved by addressing important questions that consumers have concerning depression, as well as by creating higher quality content in the areas of psychological, neurotherapeutic, and alternative treatments. 相似文献108.
Four-day incubation period for blood culture bottles processed with the Difco ESP blood culture system.
下载免费PDF全文
![点击此处可从《Journal of clinical microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
G V Doern A B Brueggemann W M Dunne S G Jenkins D C Halstead J C McLaughlin 《Journal of clinical microbiology》1997,35(5):1290-1292
Blood culture records from 1994 to 1995 from five U.S. medical centers all using the Difco ESP continuous monitoring blood culture system were reviewed retrospectively. Among a total of 7,362 isolates of bacteria and yeasts, only 0.1% of possibly significant isolates would have been missed had blood cultures been routinely incubated for 4 days instead of the 5 days recommended by the manufacturer. Conversely, numerous contaminants, detected only on day 5, would have been eliminated by a 4-day incubation period. 相似文献
109.
Immunohistological study of the anatomic relationship of toxoplasma antigens to the inflammatory response in the brains of mice chronically infected with Toxoplasma gondii. 总被引:4,自引:3,他引:4
下载免费PDF全文
![点击此处可从《Infection and immunity》网站下载免费的PDF全文](/ch/ext_images/free.gif)
The relationship of toxoplasma antigen(s) to the origin and long-term persistence of the mononuclear cell inflammatory infiltrate that is present in the brains of mice chronically infected with Toxoplasma gondii was studied by using the peroxidase-antiperoxidase immunohistochemical staining technique. C3H/Km mice were infected with the avirulent C37 strain of T. gondii and sequentially sacrificed over the ensuing 107 days. Comparable sections of each brain were prepared for routine light microscopy. Antisera to toxoplasma made in rabbits were used for immunohistological staining, and adjacent slides were also stained with conventional histological stains. The peroxidase-antiperoxidase stain demonstrated toxoplasma tissue cysts, tachyzoites, and intra- and extracellular antigen-antibody reaction products. Early infection was characterized by small tight clusters of free tachyzoites gaining access to brain substance in the absence of an inflammatory response. Once there was disruption of neural parenchyma, a mononuclear cellular infiltrate rapidly ensued. After the first days of infection, mononuclear cells were always present in all infected brains and were anatomically associated with some component of toxoplasma antigen(s). The histological picture of late infection suggested that recurrent episodes of hematogenous dissemination of tachyzoites occurred in infected mice and that such episodes were at least partially responsible for persistence of an antigenic stimulus. 相似文献
110.
Use of multiple PCR primer sets for optimal detection of human papillomavirus. 总被引:10,自引:7,他引:10
下载免费PDF全文
![点击此处可从《Journal of clinical microbiology》网站下载免费的PDF全文](/ch/ext_images/free.gif)
F Karlsen M Kalantari A Jenkins E Pettersen G Kristensen R Holm B Johansson B Hagmar 《Journal of clinical microbiology》1996,34(9):2095-2100
Using multiple PCR primer sets, we tried to optimize the detection of human papillomavirus (HPV) in DNA samples isolated from 361 frozen biopsy specimens from patients with invasive cervical carcinomas. The HPVs detected were placed into three distinct groups, including group I/Inex at Telelab (Skien, Norway) and group Ineg and group II at the Norwegian Radium Hospital (Oslo, Norway). The consensus primer sets were Oli-1b-oli-2i, My09-My11, Gp5-Gp6, and Gp(5+)-Gp6+ from the HPV L1 gene and CpI-CpIIG from the E1 gene. Using these consensus primers together with the type-specific primers from E6-E7, we found that 355 patients (98%) were HPV positive. Type-specific primers for HPV types 11, 16, 18, 31, 33, and 35 detected more HPV-infected patients than the most sensitive consensus primer set, while the three consensus primer sets My, Gp/Gp+, and Cp together detected more HPV-positive patients than the type-specific primers. Testing of sensitivity of the PCR with SiHa cells serially diluted in lymphocytes (HPV-negative cells) indicated a detection limit of 6,300 HPV type 16 DNA copies with consensus primers (My, Gp+, and Cp) and 126 original HPV type 16 DNA copies with type-specific primers. Comparison of the amplification results for consensus L1 primers and type-specific E6-E7 primers indicated the presence of L1 deletions in 23 of 56 samples. The conclusion is that in PCR detection systems, multiple consensus primers and type-specific primers should be used in order to detect all patients harboring HPV. 相似文献