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991.
To investigate an association between colon cancer and obesity during early adulthood—a potentially important period in the etiology of this disease—the authors assembled, by computer linkage, a population-based historical cohort of 52,539 men born between 1913 and 1927 residing in Hawaii (USA), for whom weight and height had been recorded in 1942–43 and 1972. Linkage of this cohort to the Hawaii Tumor Registry resulted in the identification of 737 incident cases of colorectal cancer for 1972–86. An average of 3.8 cancer-free controls were matched to each case on month and year of birth and ethnicity of the parents. A case-control analysis in each anatomic subsite of the large bowel revealed that both early and middle-age body mass increased the risk of sigmoid cancer in men in a dose-dependent fashion. The odds ratios (OR) for sigmoid cancer for the highest compared with the lowest tertiles of Quetelet index were: 2.1 (95 percent confidence interval [CI]=1.4–3.2) and 1.7 (CI=1.1–2.5), at ages 15–29 and in prediagnostic years, respectively. These associations were additive and idependent of socioeconomic status. Men who were above the median Quetelet index in 1942 and 1972 had an OR of 2.7 (CI=1.8–4.0), compared with those who were below the median in both periods. This study provides further evidence for an association of obesity with colon cancer in men and suggests that this association is limited to the sigmoid colon and may be related to both early and late events of colon carcinogenesis.The authors are with the Epidemiology Program, Cancer Research Center of Hawaii, University of Hawaii. Address correspondence to Dr Le Marchand, Epidemiology Program, Cancer Research Center of Hawaii, 1236 Lauhala Street, Suite 407, Honolulu, HI 96813, USA. This work was supported in part by Public Health Service grant 5-R29-CA44503 and contract NO1-CN-55424 from the National Cancer Institute, National Institutes of Health, Department of Health and Human Services. 相似文献
992.
目的 进一步了解肝癌患者的异常免疫状态,探讨血清、腹水中可溶性肿瘤坏死因子受体-p55(sTNFR-p55)检测的临床意义。方法 以双单抗夹心酶免疫吸附法检测了25例肝癌患者和25例肝硬化患者的血清、腹水中血清sTNFR-p55水平并以正常人为对照。结果肝癌病人血清sTNFR-p55浓度[(0.74±0.50)ng/ml]显著高于正常人[(0.37±0.03)ng/ml]和肝硬化患者和[(0.35±0.02)ng/ml],P<0.01。肝癌病人腹水sTNFR-p55浓度[(1.11±1.25)ng/ml]亦显著高于肝硬化患者[(0.33±0.03)ng/ml],P<0.01。肝癌、肝硬化患者血清与腹水的sTNFR-p55水平显著相关。肝癌患者血清sTNFR-p55水平与外周血TBil和AFP呈正相关(r=0.524,P=0.01和r=0.234,P=0.03)。结论 sTNFR-p55的检测对反映肝癌患者的异常免疫状态和肿瘤诊断具有实用价值。 相似文献
993.
Keiji Ogura Shigeki Fukuzawa Tomonori Habuchi Osamu Ogawa Osamu Yoshida 《International journal of urology》1997,4(6):561-565
Background :
In an attempt to determine the biological significance of nuclear morphometric findings, measurements of mean nuclear volume (MNV) and nuclear roundness factor (NRF) were compared to the immunoreactivityof p53 expression and proliferating cell nuclear antigen (PCNA) in human bladder cancer.
Methods :
MNV and NRF were measured using stereological methods. Expression of p53 and PCNA were determined by immunohistochemical staining. Specimens from 111 patients with previously untreated bladder cancer were analyzed.
Results :
The mean MNV was 235.8 ± 1 33.6 μm3 for the 81 patients with p53-labeling index (LI) less than 10% and 337.2 ± 141.0 μn3 for the 30 patients with p53 LI greater than 10% (P = 0.008). There was Resign if icant correlation between NRF and expression of p53. The mean MNV was 220.1 ± 1 20.5 μm3 for the 67 patients with PCNA LI less than 28% (the mean value of PCNA LI) and 328.9 ± 149.2 μm3 in 44 patients with PCNA LI greater than 28% (P= 0.0001). The mean NRF was 80.7 ± 4.2 for the 67 patients with PCNA LI less than 28%, and 82.3 ± 3.4 for the 44 patients with PCNA LI more than 28% (P= 0.04). Conclusion: Nuclear morphometric findings may reflect the proliferative potential of cancer eel Is of the bladder, as indicated by findings of immunostaining for p53 and PCNA. 相似文献
In an attempt to determine the biological significance of nuclear morphometric findings, measurements of mean nuclear volume (MNV) and nuclear roundness factor (NRF) were compared to the immunoreactivityof p53 expression and proliferating cell nuclear antigen (PCNA) in human bladder cancer.
Methods :
MNV and NRF were measured using stereological methods. Expression of p53 and PCNA were determined by immunohistochemical staining. Specimens from 111 patients with previously untreated bladder cancer were analyzed.
Results :
The mean MNV was 235.8 ± 1 33.6 μm
994.
Tetsuji Kai Yang Il Kim Hirokazu Kitamura Katsunori Kawano Seigo Kitano 《Journal of Hepato-Biliary-Pancreatic Surgery》1997,4(4):423-430
There is a growing body of evidence that the cytokine, tumor necrosis factor-α (TNF-ga), plays an important role in the development
of hepatic ischemia/reperfusion injury. We found that the immunosuppressants, cyclosporine-A (CsA), azathioprine, and FK506,
have protective effects on such injury. The purpose of the present study was to elucidate mechanisms involved in these beneficial
effects of the immunosuppressant, CsA, on liver injury following cold preservation and transplantation, with special reference
to the suppression of TNF-α release. Rat livers were stored in Euro-Collins solution (EC) at 4°C for 6h and orthotopically
transplanted. The animals allotted to two groups: group A (untreated controls) and group B (CsA pretreatment of recipients).
CsA (10 mg/kg, p.o.) was given for 3 consecutive days preoperatively. CsA pretreatment of the recipients significantly improved
the 2-week survival rate (0/6 for group A, 3/6 for group B;P<0.05) and this was associated with a significant decrease in serum TNF-α levels 2h posttransplantation (group A, 69.8±15.7
pg/ml; group B, 22.8±6.8; mean±SEM;n=12 each;P<0.05) and amelioration of sinusoidal endothelial injury, assessed by electron microscopy. Plasma endotoxin levels following
reperfusion of the grafts were not altered by the CsA therapy. Morphologically, CsA pretreatment of the recipients did not
alter activation of Kupffer cells. CsA pretreatment of the recipient aids in preventing cold preservation/reperfusion injury
of the liver graft, possibly by modulating effects of TNF-α. 相似文献
995.
Dr. David M. Euhus MD Lucille Kimura PhD Bruce Arnold MD 《Annals of surgical oncology》1997,4(5):432-439
Background: Mice immunized with murine mammary carcinoma cells genetically engineered to secrete interleukin-2 (IL-2) are rendered resistant
to subsequent challenge with unmodified tumor cells, and in the case of mice bearing established tumors, the rate of development
of pulmonary metastases is reduced. Despite these encouraging animal results, little is known about the induction of antitumor
immunity by IL-2 gene transfer in human breast cancer.
Methods: Adenovirally mediated IL-2 gene transfer was performed in 12 tumor fragment cultures established from seven primary breast
cancers. Autologous tumor infiltrating lymphocytes (TILs) or peripheral blood mononuclear cells (PBMCs) were cocultured with
transduced tumor fragments, and changes in phenotype and cytotoxicity were measured.
Results: IL-2 was never detectable in the untransduced cultures, but it peaked at 5.0—1,324.8 ng/ml in the transduced cultures. Lymphocyte
counts declined in all untransduced cultures, but they increased two- to sevenfold in four transduced cultures. CD4:CD8 ratios
decreased from a mean of 2.11 at baseline to 1.27 after stimulation in coculture (p=0.03). Expansion of lymphocytes expressing
the natural killer cell phenotype (CD3−CD56+) occurred in only one culture, but the CD3+CD56+ population increased in four of six cultures. Lymphocytes from four of 10 cocultures generated significant cytotoxicity against
allogeneic breast cancer cells. Induction of cytotoxicity correlated with expansion of the CD3+CD56+ phenotype (R2=0.805, p=0.02).
Conclusions: IL-2 gene expression by human breast cancer causes expansion of CD3+CD56+ cytotoxic lymphocytes. This phenotype is consistent with that of a non-major histocompatibility complex (MHC)-restricted
cytokine induced killer cell population previously described.
Opinions, interpretations, conclusions and recommendations are those of the author and are not necessarily endorsed by the
U.S. Army.
Presented at the 49th Annual Cancer Symposium of The Society of Surgical Oncology, Atlanta, Georgia, March 21–24, 1996. 相似文献
996.
Gülin Vural Mustafa Ünlü Tamer Atasever Izlem Özur Ayşegül Özdemir Nahide Gökçora 《European journal of nuclear medicine and molecular imaging》1997,24(3):312-315
Indium-111 octreotide and thallium-201 scintigraphic studies were compared in 21 patients (16 with palpable and five with non-palpable lesions) suspected of having breast malignancies on the basis of mammography. Early (15 min) and late (3 h)201Tl (111 MBq) and 4-h and 24-h111In-octreotide (111–148 MBq) static planar anterior images (matrix 256×256) were obtained on separate days. Images were evaluated both visually and quantitatively. Biopsy was performed following the imaging studies. Histopathology revealed 17 breast carcinomas (15 cases of invasive ductal carcinoma, one mucinous adenocarcinoma and one intraductal carcinoma) and four benign breast lesions (two fibroadenomas, one abscess and one case of fat necrosis). The means histopathologcial tumour size (mean largest diameter) was 3.38±1.9 cm.111In-octreotide detected 16 of the 17 breast cancers (94%) while201Tl detected 13 of them (76%). Both111In-octreotide and201Tl missed one nonpalpable carcinoma showing only an isolated cluster of microcalcifications on mammography. The smallest tumour size detected by both agents 1.5×1.5 cm. Of the four benign lesions, only the breast abscess revealed both201Tl and111In-octreotide uptake.111In-octreotide scan also showed tracer uptake in five of the six patients with histologically proven axillary metastases, while four of these six patients showed201Tl uptake. The tumour/background (T/B) ratios of late111In-octreotide and201Tl images were 1.71±0.38 and 1.46±0.30 respectively (P=0.039). In this preliminary study,111In-octreotide yielded more favourable results than201Tl in the detection of breast carcinomas. However, the diagnostic efficacy of111In-octreotide imaging needs to be investigated in larger patient series. 相似文献
997.
Abstract: Most individuals concerned about hereditary breast cancer risk will neither order nor benefit from genetic testing at the present time. Many will, however, seek information about their risk and testing. Risk assessment services, in addition to providing information about hereditary risk and genetic testing, need also to include assessment of non-hereditary risks, information about how to evaluate risks, early detection modalities, the etiology of cancer, and assistance in devising follow-up health care plans. Psychosocial factors, particularly those pertaining to the individual's past history with illness and beliefs about causes and prognosis, must be taken into account to provide relevant information that is understood. A case history with examples of some of the types of information that lead to informed consent in a cancer risk assessment setting is provided. 相似文献
998.
人群归因危险度百分比 (populationattributableriskproportion ,PARP)是总体人群中某种疾病归因于某种因素的暴露所引起的发病 (死亡 )占全部发病 (死亡 )的百分比 ,反映该因素所引起的发病 (死亡 )占全部发病 (死亡 )的比重。通过PARP可了解各危险因素对人群中某疾病的发病所产生的影响 ,亦即消除某危险因素后 ,所产生的对预防该疾病的效果将占有多大比重。它能够为卫生政策的制订提供依据 ,有着重要的公共卫生的实际意义。目前常用的估计PARP的方法有两种 :一种是利用全国人群抽样调查获得的人群总暴露率来估计 ;另一种是利用某地区… 相似文献
999.
1000.
The purpose of our study was to test the hypothesis that the quotient between plasma glucose and whole body oxygen consumption (VO2) as a 'metabolic index' is a sensitive indicator of early graft function. Arterial levels of glucose and oxygen consumption were determined in 100 consecutive patients during orthotopic liver transplantation performed without anhepatic veno-venous bypass. Patients were divided into survivors with no obvious problems related to graft function and those with primary nonfunction of the graft. The neohepatic increase in VO2 was significantly higher in survivors (112 +/- 4 vs 88 +/- 11 ml.min-1.m-2; p < 0.05), whereas blood glucose levels after reperfusion were higher (352 +/- 18 vs. 287 +/- 36 mg dl-1) in those with primary non-function of the graft. The calculated metabolic index was also higher (4.02 +/- 0.93 vs 2.67 +/- 0.45, p < 0.05) in patients with primary nonfunction of the graft. Our principal conclusion was that 92% of normal functioning liver grafts could be classified correctly by the metabolic index immediately after reperfusion, whereas glucose levels and VO2 alone classified only 67% and 70% of normal functioning liver grafts correctly. 相似文献