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31.
Juliana F. W. Cohen Amelie A. Hecht Gabriella M. McLoughlin Lindsey Turner Marlene B. Schwartz 《Nutrients》2021,13(3)
The school environment plays an important role in children’s diets and overall health, and policies for universal free school meals have the potential to contribute to positive child health outcomes. This systematic review evaluates studies examining the association between universal free school meals and students’ school meal participation rates, diets, attendance, academic performance, and Body Mass Index (BMI), as well as school finances. The search was conducted in accordance with the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA). A search for studies published in economically developed countries published through December 2020 was performed in PubMed, Education Resources Information Center (ERIC), Thomson Reuters’ Web of Science, and Academic Search Ultimate, followed by examining the references in the resultant literature. A total of 47 studies were identified and the Newcastle-Ottawa Scale (NOS) was applied to assess bias. Nearly all studies examining universal free school meals found positive associations with school meal participation. Most studies examining universal free school meals that included free lunch found positive associations with diet quality, food security, and academic performance; however, the findings of studies examining only universal free breakfast were mixed. Research findings were similarly mixed when examining attendance as an outcome. Concerns about adverse outcomes on student BMI were not supported by the literature; in fact, several studies detected a potentially protective effect of universal free school meals on BMI. Research examining the impact of universal free meals on school finances was limited, but suggest that lower-income school districts in the U.S. may have positive financial outcomes from participation in universal free school meal provisions. Additionally, providing free meals to students may be associated with improved household incomes, particularly among lower-income families with children. Further research is needed to examine the financial implications of universal free meals for both school districts and families. Overall, universal free school meals may have multiple benefits for students and countries should consider universal free school meal provisions with strong nutrition guidelines. (PROSPERO registration: CRD42020221782). 相似文献
32.
Guz Samantha Hecht Hillary K. Kattari Shanna K. Gross E. B. Ross Emily 《Archives of sexual behavior》2022,51(4):2135-2145
Archives of Sexual Behavior - Research on asexuality as a part of the experience of human sexuality has increased over the last two decades. However, there has not yet been a systematic review of... 相似文献
33.
OBJECTIVE: The purpose of this study was to evaluate the effectiveness of CT colonography when patients were imaged in both the supine and prone positions. We evaluated whether imaging in two positions decreased the number of collapsed colonic segments and increased sensitivity for polyp detection. MATERIALS AND METHODS: Twenty-three patients underwent CT colonography in both the supine and prone positions. Colonic distention for each of the 46 scans was graded. Adequacy of distention for either position alone was compared with that of the combination of the two positions. Polyp data revealed by colonoscopy were reviewed, and the CT data were then retrospectively reviewed for polyp detection. RESULTS: When each scan was considered alone without benefit of the scan obtained in the opposite position, 27 (58.7%) of 46 scans showed inadequate distention. When scans obtained in both positions were considered together, 20 (87.0%) of 23 patients had adequate distention with the grading system used. However, this value increased to 23 (100%) of 23 patients when the reasons for inadequate distention in the three patients were considered. Of the 27 polyps detected with colonoscopy, 21 (77.8%) were also detected retrospectively with CT colonography. Colonoscopy showed 20 polyps that were 5 mm or larger; nineteen (95.0%) of these 20 polyps were also detected retrospectively with CT colonography, nine (47.4%) of which were seen in only one position. CONCLUSION: Use of both the supine and prone positions for patients undergoing CT colonography improves evaluation of the colon and increases sensitivity for polyp detection. 相似文献
34.
Hecht F 《AIDS clinical care》1996,8(9):72, 75
There are two potential goals of very early treatment of HIV infection. One is to see whether aggressive treatment during the primary phases of infection can improve the long-term course. The other is to test the feasibility of eradicating HIV infection. Eradication may be simpler in newly-infected patients who are likely to have less damage to the immune system and whose virus may be more homogeneous and less drug resistant. 相似文献
35.
A detailed study of the urinary metabolites of N'-nitrosonornicotinehas been perfomed, employing a simple high pressure liquid chromatographicmethod. The percentage excretion of the principal urinary metaboliteswas determined over a dose range of 3300 mg/kg in theF-344 rat, as follows: 4-hydroxy-4-(3-pyridyl)butyric acid (37.153.3%,respectively, of the dose), N'-nitrosonornicotine-l-N-oxide(6.710.7%), norcotinine (3.25.1%), 4-oxo-4-(3-pyridyl)butyricacid (31.112.8%), N' -nitrosonornicotine (3.35.2%).In the strain A mouse and Syrian golden hamster, the urinarymetabolites were qualitatively similar to those observed inthe F-344 rat. The interrelationships of the various metabolitesof N'-nitrosonornicotine which have been observed in vitro andin vivo were established. The in vitro metabolites resultingfrom 2'-hydroxylation by liver microsomes, myosmine and 4-hydroxy-l-(3-pyridyl)-1-butanonewere converted, by the F-344 rat, primarily to 4-oxo-4-(3-pyridyl)butyricacid as a urinary metabolite. The in vitro metabolite resultingfrom 5'-hydroxylation by liver microsomes, 2-hydroxy-5-(3-pyridyl)tetrahydrofuran,gave 4-hydroxy-4-(3-pyridyl)butyric acid as its major urinarymetabolite, apparently via 5-(3-pyridyl)-tetrahydrofuran-2-one.N'-nitrosonornicotine-l-N-oxide, the remaining major in vitrometabolite, was excreted to a large extent unchanged in F-344rat urine. The urinary metabolites from 2'-hydroxylation and5'-hydroxylation of N'-nitrosonornicotine, 4-oxo-4-(3-pyridyl)butyricacid and 4-hydroxy-4-(3-pyridyl)butyric acid, respectively,were not formed from the in vivo metabolite norcotinine andwere not interconverted significantly by the F-344 rat. Thus,these metabolites appear to be reliable indicators for the twopossible in vivo -hydroxylations of N'-nitrosonornicotine. 相似文献
36.
Doses of d-amphetamine sulfate (0.1, 0.15, and 0.2 mg/kg body weight) were given to adult monkeys in mother—infant pairs. The fundamental parental care behavior pattern was disrupted and the mother became isolated in a socially withdrawn phase. She did not respond to the calling signals of the infant and showed behavior in which stereotyped self-grooming and/or staring into space were predominant. The reactions of the infant to this amphetamine-induced behavior were different in the two experimental pairs. In group 1 the infant increased its approach—avoidance movements. In group 2 the infant sat very quietly and close in front of the mother. The mother from group 1 reacted to the increased approaches from its ininfant with active rejection. In both groups the mothers did not react with the typical ventral—ventral grasping to either the infants sitting close or to the social anxiety signals of the infants. In spite of differences in behavior changes induced by amphetamine, the main conclusion is that the mothers totally lost their normal and highly biologic significant interest in their infants. 相似文献
37.
J Randolph Hecht Rudolph Bedford James L Abbruzzese Sandeep Lahoti Tony R Reid Roy M Soetikno David H Kirn Scott M Freeman 《Clinical cancer research》2003,9(2):555-561
PURPOSE: Localized pancreatic carcinoma is rarely resectable and is resistant to conventional therapies. ONYX-015 (dl1520) is an E1B-55kD gene-deleted replication-selective adenovirus that preferentially replicates in and kills malignant cells. Endoscopic ultrasound (EUS) has the potential to conveniently and accurately deliver local therapy to the pancreas. Therefore, we undertook a trial of the feasibility, tolerability, and efficacy of EUS injection of ONYX-015 into unresectable pancreatic carcinomas. EXPERIMENTAL DESIGN: Twenty-one patients with locally advanced adenocarcinoma of the pancreas or with metastatic disease, but minimal or absent liver metastases, underwent eight sessions of ONYX-015 delivered by EUS injection into the primary pancreatic tumor over 8 weeks. The final four treatments were given in combination with gemcitabine (i.v., 1,000 mg/m(2)). Patients received 2 x 10(10) (n = 3) or 2 x 10(11) (n = 18) virus particles/treatment. RESULTS: After combination therapy, 2 patients had partial regressions of the injected tumor, 2 had minor responses, 6 had stable disease, and 11 had progressive disease or had to go off study because of treatment toxicity. No clinical pancreatitis occurred despite mild, transient elevations in lipase in a minority of patients. Two patients had sepsis before the institution of prophylactic oral antibiotics. Two patients had duodenal perforations from the rigid endoscope tip. No perforations occurred after the protocol was changed to transgastic injections only. CONCLUSIONS: This study indicates that ONYX-015 injection via EUS into pancreatic carcinomas by the transgastic route with prophylactic antibiotics is feasible and generally well tolerated either alone or in combination with gemcitabine. Transgastric EUS-guided injection is a new and practical method of delivering biological agents to pancreatic tumors. 相似文献
38.
We compared the tumor-initiating activities toward mouse skin of two
structurally related polycyclic aromatic hydrocarbon diol epoxides: racemic
anti-1,2,3,4-tetrahydro-5,6-dimethylchrysene-1,2-diol-3,4- epoxide
(5,6-diMeCDE) and racemic anti-1,2,3,4-tetrahydro-5-
methylchrysene-1,2-diol-3,4-epoxide (5-MeCDE). Tumors induced by these diol
epoxides were analysed for mutations in the Ha-ras gene. 5,6- diMeCDE is
derived from the non-planar parent compound 5,6- dimethylchrysene, and
reacts to approximately equal extents with dA and dG in DNA, whereas
5-MeCDE is derived from a nearly planar parent compound, 5-methylchrysene,
and reacts mainly with dG in DNA. 5,6- diMeCDE, at initiating doses of 33,
100 or 400 nmol per mouse, induced 1.2, 2.2 and 6.2 skin tumors per mouse,
respectively. It was significantly less tumorigenic than 5-MeCDE which
induced 3.1, 7.5 and 9.1 skin tumors per mouse at the same doses. Tumors
induced by 5,6- diMeCDE had a large number of CAA-->CTA mutations in
codon 61 of the Ha- ras gene: 50, 55 and 75% of the tumors analysed had
this mutation at the 33, 100 and 400 nmol doses. No mutations were found in
codons 12 and 13 in the tumors induced by 5,6-diMeCDE. In contrast,
CAA-->CTA mutations in codon 61 were rarely seen in tumors induced by
5-MeCDE. At the highest dose of 5-MeCDE, 20% of the tumors analysed had
mutations at G of codons 12 and 13. The results of this comparative study
support the hypothesis that mutations in the Ha-ras gene in mouse skin
tumors induced by PAH diol epoxides occur as a result of their direct
reaction with the gene. However, pathways other than the commonly observed
Ha- ras codon 61 mutations are clearly important in mouse skin
tumorigenesis by these diol epoxides.
相似文献
39.
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