全文获取类型
收费全文 | 8065篇 |
免费 | 354篇 |
国内免费 | 59篇 |
专业分类
耳鼻咽喉 | 27篇 |
儿科学 | 140篇 |
妇产科学 | 57篇 |
基础医学 | 949篇 |
口腔科学 | 124篇 |
临床医学 | 478篇 |
内科学 | 2070篇 |
皮肤病学 | 128篇 |
神经病学 | 451篇 |
特种医学 | 344篇 |
外科学 | 1416篇 |
综合类 | 59篇 |
一般理论 | 2篇 |
预防医学 | 493篇 |
眼科学 | 175篇 |
药学 | 398篇 |
中国医学 | 15篇 |
肿瘤学 | 1152篇 |
出版年
2023年 | 47篇 |
2022年 | 91篇 |
2021年 | 170篇 |
2020年 | 99篇 |
2019年 | 125篇 |
2018年 | 151篇 |
2017年 | 127篇 |
2016年 | 172篇 |
2015年 | 159篇 |
2014年 | 259篇 |
2013年 | 340篇 |
2012年 | 556篇 |
2011年 | 567篇 |
2010年 | 314篇 |
2009年 | 272篇 |
2008年 | 508篇 |
2007年 | 539篇 |
2006年 | 493篇 |
2005年 | 499篇 |
2004年 | 476篇 |
2003年 | 449篇 |
2002年 | 478篇 |
2001年 | 127篇 |
2000年 | 84篇 |
1999年 | 115篇 |
1998年 | 110篇 |
1997年 | 93篇 |
1996年 | 111篇 |
1995年 | 85篇 |
1994年 | 63篇 |
1993年 | 69篇 |
1992年 | 76篇 |
1991年 | 67篇 |
1990年 | 87篇 |
1989年 | 79篇 |
1988年 | 83篇 |
1987年 | 49篇 |
1986年 | 31篇 |
1985年 | 39篇 |
1984年 | 32篇 |
1983年 | 33篇 |
1982年 | 29篇 |
1981年 | 19篇 |
1980年 | 12篇 |
1979年 | 16篇 |
1978年 | 9篇 |
1977年 | 12篇 |
1976年 | 8篇 |
1974年 | 13篇 |
1966年 | 5篇 |
排序方式: 共有8478条查询结果,搜索用时 46 毫秒
101.
Crime is seldom considered as an outcome in public health research. Yet major theoretical and empirical developments in the field of criminology during the past 50 years suggest that the same social environmental factors which predict geographic variation in crime rates may also be relevant for explaining community variations in health and wellbeing. Understanding the causes of variability in crime across countries and across regions within a country will help us to solve one of the enduring puzzles in public health, viz. why some communities are healthier than others. The purpose of this paper is to present a conceptual framework for investigating the influence of the social context on community health, using crime as the indicator of collective wellbeing. We argue that two sets of societal characteristics influence the level of crime: the degree of relative deprivation in society (for instance, measured by the extent of income inequality), and the degree of cohesiveness in social relations among citizens (measured, for instance, by indicators of 'social capital' and 'collective efficacy'). We provided a test of our conceptual framework using state-level ecologic data on violent crimes and property crimes within the USA. Violent crimes (homicide, assault, robbery) were consistently associated with relative deprivation (income inequality) and indicators of low social capital. Among property crimes, burglary was also associated with deprivation and low social capital. Areas with high crime rates tend also to exhibit higher mortality rates from all causes, suggesting that crime and population health share the same social origins. Crime is thus a mirror of the quality of the social environment. 相似文献
102.
Toshi Nomura Katsuhiro Inoue Cyrus R. Creveling Fuhito Komatsu Norio Ohta Takehiro Chino Nobuyuki Karasawa Ikuko Nagatsu 《Brain research》1996,735(2):314
Relatively large amounts of DOPA as compared with the concentration of norepinephrine are found in human dental pulp. AADC and COMT are localized in blood vessel walls of human dental pulp. This localization suggests a functional relationship between COMT and AADC with regard to the metabolism of DOPA. 相似文献
103.
Tsuda Hiroyuki; Sakata Takao; Tamano Seiko; Okumara Masanao; Ito Nobuyuki 《Carcinogenesis》1983,4(5):523-528
Sequential observations were carried out on the induction ofpreneoplastic lesions in the liver and the kidney. Rats wereinitially given N-ethyl-N-hydroxyethylnitrosamine (EHEN) intheir drinking water (0.1%) for 3 days (Group 1), 1 week (Group2) or 2 weeks (Group 3) or tap water (Group 4). Rats in Groups1 3 were subjected to partial hepatectomy and unilateralnephrectomy (right side) 2 weeks after the end of EHEN treatment.Rats from these groups were killed in week 10, 20, 30 and 40of the experiment. In the liver, the effect of EHEN in the inductionof -glutamyltranspeptidase (-GT) positive foci and hyperplasticnodules (HN) was clearly dependent on the length of treatment.The preneoplastic lesions increased with the lapse of observationtime. Changes measured as number of -GT positive foci were 1040times greater than those measured as HN, especially among thesmall size range. Values for changes in Group 1 given 0.1% EHENfor 3 days were very low, indicating that this dose is closeto the threshold. Two rats with hepatocellular carcinoma inGroup 3 given EHEN for 2 weeks survived until week 40. In thekidney, tubular epithelial proliferations composed of cellswith slightly basophilic cytoplasm and slightly atypical nucleiwere tentatively named atypical cell foci (ACF). EHEN inducedACF, renal cell adenomas and renal cell carcinomas. The increasein the induction of ACF was dependent on the length of observationperiod but not on the length of treatment. Even though controlrats (not treated with EHEN) also had ACF, their quantitativevalues were far less than the groups given EHEN and killed atweek 40, indicating that a large number of ACF were inducedby EHEN. Therefore, EHEN is good for experimental inductionof preneoplastic lesions in the liver and kidney of rats. Theexperimental schedule for Groups 1 and 2 could be used as ashort-term screening test for promoters and the schedule forGroup 3 as an assay for inhibitors. 相似文献
104.
ChangmingGao TakezakiToshiro JianzhongWu JianhuoDing YantingLiu SupingLi PingSu XuHu TianliongXu HamajimaNobuyuki TajimaKazuo 《中国肿瘤临床(英文版)》2004,1(3):162-166
OBJECTIVE To study the relation among methylenetetrahydrofolate reductase (MTHFR) C677T genotypes, dietary habits and the risk of stomach cancer (SC).METHODS A case-control study was conducted with 107 cases of SC and 200 population-based controls in Chuzhou district, Huaian, Jiangsu province, China. The epidemiological data were collected, and DNA of peripheral blood leukocytes was obtained from all of the subjects..MTHFR genotypes were detected by PCR-RFLP. RESULTS (1) The prevalence of the MTHFR C/T or T/T genotypes was found to be significantly different between controls (68.5%) and SC cases (79.4%,P=0.0416), the increased risk had an adjusted OR of 1.79 (95?:1.01-3.19). (2) Among subjects who had a low intake of garlic or Chinese onion, MTHFR C/T or T/T genotypes significantly increased the risk of developing SC. Among non-tea drinkers or among subjects who had a frequent intakeof meat, the carriers of the MTHFR C/T or T/T genotypes had a higher risk of SC than individuals with the C/C type MTHFR. CONCLUSION The polymorphism of MTHFR C677T was associated with increased risk of developing SC, and that individuals with differing genotypes may have different susceptibilities to SC, based on their exposure level to environmental factors. 相似文献
105.
Functional impact of breast cancer by age at diagnosis. 总被引:5,自引:0,他引:5
Candyce H Kroenke Bernard Rosner Wendy Y Chen Ichiro Kawachi Graham A Colditz Michelle D Holmes 《Journal of clinical oncology》2004,22(10):1849-1856
PURPOSE: To explore changes in physical and psychosocial function before and after breast cancer by age at diagnosis. PATIENTS AND METHODS: A total of 122,969 women from the Nurses' Health Study (NHS) and NHS 2, ages 29 to 71 years, who responded to pre- and postfunctional status assessments were included; 1,082 women were diagnosed with breast cancer between 1992 and 1997. Functional status was measured using the Medical Outcomes Study Short Form 36 (SF-36). Mean change in health-related quality of life (HRQoL) scores was computed across categories representing the combination of incident breast cancer (yes or no) and age at diagnosis (< or = 40, 41 to 64, or 65+ years). RESULTS: Compared with women < or = 40 years without breast cancer, women with breast cancer experienced significant functional declines. Young (age < or = 40) women who developed breast cancer experienced the largest relative declines in HRQoL (as compared with middle-aged and elderly women) in multiple domains including physical roles (-18.8 v -11.5 and -7.5 points, respectively), bodily pain (-9.0 v -2.7 and -2.7 points), social functioning (-11.3 v -4.3 and -4.4 points) and mental health (-3.1 v 0.0 and +0.4 points). Much of the decline in HRQoL among elderly (age > or = 65) women with breast cancer was age related. CONCLUSION: Young women may fare worse than middle-aged or elderly women in both physical and psychosocial dimensions after breast cancer diagnosis. The needs of women facing breast cancer may be better understood within a life stage framework. 相似文献
106.
107.
Nobuyuki Hamajima Atsuko Shibata Nobuyuki Katsuda Keitaro Matsuo Hidemi Ito Toshiko Saito Kazuo Tajima Suketami Tominaga 《Gastric cancer》2003,6(4):230-236
Background A possible association between Helicobacter pylori seropositivity and tumor necrosis factor (TNF) A G-308A has been reported in Korea. The present study examined the associations of H. pylori with functional polymorphisms, TNF-A G-308A, C-857T, and T-1031C, and TNF-B A252G in Japanese subjects.Methods The total of 1374 study subjects included 241 outpatients who participated in an H. pylori eradication program (HPE), 679 first-visit outpatients (FVO) at a regional cancer hospital, and 454 local residents who received a health checkup examination (HCE).Results The frequency of the TNF-A -308A allele was only 1.3% of 480 chromosomes in the HPE group, so the FVO and HCE groups were not genotyped for that polymorphism. The genotype frequency of TNF-A C-857T was 69.2% CC, 27.7% CT, and 3.1% TT; that of TNF-A T-1031C was 69.4% TT, 28.1% TC, and 2.5% CC; and that of TNF-B A252G was 36.8% AA, 48.2% AG, and 15.0% GG. TNF-A -857T was tightly linked to TNF-A -1031T and TNF-B 252A. No significant associations between H. pylori seropositivity and polymorphisms of TNF-A C-857T and TNF-B A252G were observed. However, a reduced odds ratio adjusted for sex, age, and recruitment source was observed for TNF-A -1031CC (0.43; 95% confidence interval, 0.20–0.91) relative to TNF-A -1031TT. Subjects with TNF-A -857CC and -1031CC showed the lowest seropositivity (38.2% of 34 participants), while those with TNF-A -857TT and -1031TT showed the highest (66.7% of 42 participants).Conclusions This study suggests that the possibly high expression genotype of TNF-A may increase susceptibility to persistent H. pylori infection. 相似文献
108.
Abul Mokarim Masataka Uetani Ichiro Sakamoto Nobuyuki Hayashi Koichiro Nomata Hiroshi Ohtani 《Acta oncologica (Stockholm, Sweden)》1997,36(2):175-181
Forty-five patients (median age 63 years) with muscle invasive bladder cancer were treated with transcatheter intraarterial infusion (TAI) of cisplatin (CDDP) and doxorubicin. They received a total of 114 courses (median 3 courses per patient) of TAI. Complete response was obtained in 20 patients (44%), partial response in 17 (38%), stable disease in 6(13%), and progression of disease in 2 patients (5%). The overall response rate was 82% at a median follow-up of 36 months. The actuarial survival of the patient population was 72% at 5 years; 36 patients were alive and 9 had died of cancer progression. The treatment was generally extremely well tolerated without major complications. The current study also revealed the fact that papillary carcinomas were more sensitive to this therapy than were non-papillary tumors. Overall, response rate and local control were significantly higher in low-grade than in high-grade tumors. The observed high complete response and good survival rate suggest that intraarterial CDDP and doxorubicin might be highly effective for localized invasive bladder cancer. 相似文献
109.
Abstract Background. Fluorescence in situ hybridization (FISH) has allowed the detection of numerical chromosomal aberrations in interphase nuclei on fresh or frozen smears of leukemia.
Methods. To analyze clonality and residual disease in myeloid leukemia retrospectively, we applied FISH to bone marrow smears stored at ambient temperature for up to 9 years.
Results: When hybridization efficiency was investigated on stored control smears from patients without hematological malignancy, more than 96% of nuclei showed the expected number of signals using DNA probes specific for chromosome 7, X or Y. In combination with cell morphology, we observed much higher hybridization efficiency in blasts and granulomonocytic cells compared with lymphoid and erythroid cells. On the basis of good hybridization efficiency for old smear specimens, we applied FISH to stored bone marrow smears of myeloid leukemias, in which either loss of chromosome 7 or loss of sex chromosomes had been verified previously by conventional cytogenetics (one patient with chronic myelomonocytic leukemia (CMML) and four with acute myeloid leukemia (AML; three M2 and one M7)). As a result, the loss of chromosome was detected in blasts from all patients and was observed in mature granulocytes, except in M7. In the CMML patient and one AML (M2) patient with t(8;21), lymphoid and erythroid cells also showed the loss of chromosomes, suggesting that it should occur at stem-cell level. A high amount of residual disease was detected in the morphological remission samples in one AML (M2) patient after induction therapy. The patient eventually succumbed to relapse.
Conclusion Thus, the present FISH technique is useful to analyze the clinical significance of clonality and the residual disease in myeloid leukemia, retrospectively. 相似文献
Methods. To analyze clonality and residual disease in myeloid leukemia retrospectively, we applied FISH to bone marrow smears stored at ambient temperature for up to 9 years.
Results: When hybridization efficiency was investigated on stored control smears from patients without hematological malignancy, more than 96% of nuclei showed the expected number of signals using DNA probes specific for chromosome 7, X or Y. In combination with cell morphology, we observed much higher hybridization efficiency in blasts and granulomonocytic cells compared with lymphoid and erythroid cells. On the basis of good hybridization efficiency for old smear specimens, we applied FISH to stored bone marrow smears of myeloid leukemias, in which either loss of chromosome 7 or loss of sex chromosomes had been verified previously by conventional cytogenetics (one patient with chronic myelomonocytic leukemia (CMML) and four with acute myeloid leukemia (AML; three M2 and one M7)). As a result, the loss of chromosome was detected in blasts from all patients and was observed in mature granulocytes, except in M7. In the CMML patient and one AML (M2) patient with t(8;21), lymphoid and erythroid cells also showed the loss of chromosomes, suggesting that it should occur at stem-cell level. A high amount of residual disease was detected in the morphological remission samples in one AML (M2) patient after induction therapy. The patient eventually succumbed to relapse.
Conclusion Thus, the present FISH technique is useful to analyze the clinical significance of clonality and the residual disease in myeloid leukemia, retrospectively. 相似文献
110.
The 1.5 GHz Electromagnetic Near-field Used for Cellular Phones Does Not Promote Rat Liver Carcinogenesis in a Medium-term Liver Bioassay 总被引:3,自引:1,他引:3
Katsumi Imaida Masao Taki So-ichi Watanabe Yoshitsugu Kamimura Takayasu Ito Tsuyoshi Yamaguchi Nobuyuki Ito Tomoyuki Shirai 《Cancer science》1998,89(10):995-1002
We have recently established that local exposure to a 929.2 MHz electromagnetic near-field, used for cellular phones, does not promote rat liver carcinogenesis in a medium-term bioassay system. In the present study, a 1.439 GHz electromagnetic near-field (EMF), another microwave band employed for cellular phones in Japan, was similarly investigated. Time division multiple access (TDMA) signals for the Personal Digital Cellular (PDC) Japanese cellular telephone standard system were directed to rats through a quarter-wavelength monopole antenna. Numerical dosimetry showed that the peak SARs within the liver were 1.91–0.937 W/kg, while the whole-body average specific absorption rates (SARs) were 0.680–0.453 W/kg, when the time-averaged antenna radiation power was 0.33 W. Exposure was for 90 min a day, 5 days a week, over 6 weeks, to male F344 rats given a single dose of diethylnitrosamine (200 mg/kg, i.p.) 2 weeks previously. At week 3, all rats were subjected to a two-thirds partial hepatectomy. At week 8, the experiment was terminated and the animals were killed. Carcinogenic potential was scored by comparing the numbers and areas of the induced glutathione S-transferase placental form (GST-P)-positive foci in the livers of exposed (48) and sham-exposed rats (48). Despite increased serum levels of corticosterone, adrenocorticotropic hormone (ACTH) and melatonin, the numbers and the areas of GST-P-positive foci were not significantly altered by the exposure. These findings clearly indicated that local body exposure to a 1.439 GHz EMF, as in the case of a 929.2 MHz field, has no promoting effect on rat liver carcinogenesis in the present model. 相似文献