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101.
Obesity and subcutaneous fat patterning in relation to survival of postmenopausal breast cancer patients participating in the DOM-project 总被引:2,自引:0,他引:2
Isolde den Tonkelaar Frits de Waard Jacob C. Seidell Jacques Fracheboud 《Breast cancer research and treatment》1995,34(2):129-137
Summary The effect of obesity and fat distribution on survival of breast cancer patients was studied prospectively in 241 women with a natural menopause who participated in a breast cancer screening project, the DOM-project in Utrecht, The Netherlands. Mean follow-up time was 9.1 years and endpoint of interest was death from breast cancer. Fat distribution was assessed by contrasting groups of subscapular and triceps skinfold thickness.No significant differences in survival time between more obese (Quetelet's index 26 kg/m2) and leaner (Quetelet's index < 26 kg/m2) patients or between patients with central fat distribution and patients with peripheral fat distribution were observed. Analyses were stratified by axillary node status, estrogen receptor status, and way of detection (by first screening or afterwards). Results of the stratified analyses were suggestive of a modifying effect of these factors.The absence of an association between obesity and survival time might be explained by two counteracting mechanisms. On the one hand obesity might be related to impaired survival, due to a tumor growth promoting effect of extra-ovarian estrogens. On the other hand obesity might be related to improved survival in a screened population, because obese patients profit more from screening by earlier detection of tumors than leaner counterparts. 相似文献
102.
Chromosome 11q13 markers and D-type cyclins in breast cancer 总被引:7,自引:0,他引:7
Gordon Peters Vera Fantl Rosalind Smith Sharon Brookes Clive Dickson 《Breast cancer research and treatment》1995,33(2):125-135
Summary One in six primary human breast cancers has DNA amplification centered on the cyclin D1 gene (CCND1) on chromosome 11q13. This genetic abnormality is preferentially associated with estrogen-receptor positive tumors and may define a sub-class of patients with an adverse prognosis. AlthoughCCND1 has the credentials of a cellular oncogene, being a target for chromosomal translocation and retroviral integration, the 11q13 amplicon encompasses several other markers andCCND1 is not the only candidate for the key gene on the amplified DNA. To assess their relative importance, we have constructed a physical map of the amplified DNA and compared the extent and frequency of amplification across the region. Since it is likely that the gene providing the selective force for amplification will be expressed at elevated levels, we have also examined expression of both RNA and protein. By these criteria, cyclin D1 remains the strongest candidate for the key oncogene on the amplicon and we are currently investigating the functional consequences of its over-expression.Presented by Gordon Peters at the 16th Annual San Antonio Breast Cancer Symposium, San Antonio TX, USA, November 4, 1993; Minisymposium on Molecular Genetics in Breast Cancer. 相似文献
103.
Shigeru Masamura Herman Adlercreutz Harold Harvey Allan Lipton Laurence M. Demers Richard J. Santen Steven J. Santner 《Breast cancer research and treatment》1995,33(1):19-26
Summary Inhibition of estrogen production provides effective therapy for patients with hormone-dependent breast cancer. The source of estrogens in premenopausal women is predominantly the ovary, but after the menopause, estradiol is synthesized in peripheral tissues through the aromatization of androgens to estrogens. Uptake from plasma is the primary mechanism for maintenance of estradiol concentrations in breast cancer tissue in premenopausal women, whereas several steps may be operant in postmenopausal women. These include enzymatic synthesis of estradiol via sulfatase, aromatase, and 17-hydroxysteroid dehydrogenase in the tumor itself. Aromatization of androgens secreted by the adrenal to estrogens in peripheral tissues and transport to the tumor via circulation in the plasma provides another means of maintaining breast tumor estradiol levels in postmenopausal women. These various sources contribute to the high tissue estrogen levels measured in breast tumor tissue.To effectively suppress tissue concentrations of estrogens and circulating estradiol in postmenopausal patients, various aromatase inhibitors have been developed recently. These include steroidal inhibitors such as 4-hydroxy-androstenedione as well as non-steroidal compounds with imidazole and triazole structures. The most potent of these, CGS 20267, is reported to suppress levels of active estrogens (i.e., estrone, estrone sulfatase, and estradiol) by more than 95%. This compound can suppress both serum and 24-hrurine estrogens to a greater extent than produced by the second generation inhibitor, CGS 16949A. CGS 20267 is highly specific since it does not affect cortisol and aldosterone serum levels during ACTH stimulation tests nor sodium and potassium balance in 24-hr urine samples. These data suggest that CGS 20267 can be expected to bring improved response rates in the treatment of metastatic hormone-dependent breast cancer without substantial side effects.Presented by R.J. Santen at the 16th Annual San Antonio Breast Cancer Symposium, San Antonio TX, November 4, 1993; Mini-symposium on New Agents in Breast Cancer (supported by an educational grant from Rhône-Poulenc Rorer). 相似文献
104.
Summary The Save Our Sisters Project builds on the roles of 95 natural helpers to increase mammography screening among older African American women in a NC county. Natural helpers are lay people to whom others naturally turn for advice, emotional support, and tangible aid. Findings from 14 focus group interviews showed that older women seek out these individuals when they have a female-specific concern, rather than or before seeking help from professionals. The characteristics of natural helpers, revealed in the findings, were used to identify and recruit them to become trained lay health advisors in breast cancer education. Through the SOS Project, natural helpers provide a community-based system of care and social support that complements the more specialized role of health professionals; linking them to women through places and ways that no health professional could begin to acquire. The three roles of lay health advisors are: (1) to assist individuals in their social networks with needs that are difficult for professionals to address; (2) to negotiate with professionals for support from the health system; and (3) to mobilize the resources of associations in their community to sustain support from the health system. 相似文献
105.
The incidence and clinicopathologic features of unilateral multicentric breast cancer (UMBC) were studied by mammary gland
serial sectioning in 116 cases of clinically defined monocentric breast cancer (MONBC) examined histopathologically at the
Nagano Cancer Detection Center. UMBC was defined as: 1) histopathologically discontinuous tumors each with an intraductal
spread, 2) at least one tumor-free section separating two tumors, and 3) a large primary tumor and other small secondary tumors.
UMBC was detected in 23 of 116 cases (19.8%), all with one secondary tumor. Primary and secondary tumors were located in the
same quadrant in 34.8% and in different ones in 65.2%. The secondary tumors were <5 mm in size in 56.5%. Secondary tumors,
averaging 8.3 mm in size and 25.5 mm in distance from the primary tumor, were almost exclusively noninvasive carcinomas, including
15 (65.4%) noninvasive ductal carcinomas and several special types. The primary and secondary tumors were of the same histologic
type in 3 of 23 cases. UMBC patients averaged 6 years younger than MONBC patients, and the incidence of UMBC tended to be
higher in younger patients (p<0.1). UMBC tended to occur more frequently in quadrant with an average histologie tumor size
significantly smaller than that in MONBC (p<0.01). The histologie types of the primary tumor in UMBC and MONBC were similar,
with common types predominant. Lymph node metastases tended to be slightly more frequent in MONBC.
This high incidence of UMBC calls for careful attention when considering breast conserving therapy. 相似文献
106.
To investigate the factors influencing the quality of life (QOL) of Japanese patients with advanced or recurrent breast cancer, a newly developed QOL questionnaire, The QOL Questionnaire for Cancer Patients Treated with Anticancer Drugs (QOL-ACD), was answered by 23 patients, and a multiple regression analysis was performed. The demographic and medical factors relating to the overall QOL score and to the four categories of the QOL-ACD, namely (1) activity, (2) physical condition, (3) psychological condition, and (4) social relationships, were analyzed. The results indicated that skin metastasis, a heavier body weight, and bone metastasis had a strong negative influence on the overall QOL scroe, whereas endocrine therapy, the existence of a primary lesion, and more extensive first surgery had a strong positive influence on it. With regard to the analysis of the four categories, endocrine therapy was found to be positively related to all four categories. The multiple correlation coefficient (R) between the estimated overall QOL score and the observed overall QOL score was about 0.77. The results of this analysis showed that endocrine therapy can improve the QOL of patients with advanced or recurrent breast cancer, and that the QOL-ACD questionnaire could prove extremely useful for predicting the QOL of individual patients and for aiding clinicians in deciding on the most appropriate type of therapy for each patient. 相似文献
107.
P. G. Liavaag A. C. Johannessen R. Nilsen R. Jonsson 《European archives of oto-rhino-laryngology》1994,251(8):452-456
T-lymphocytes expressing T -cell receptors (TCRs) of the / type have been suggested to play an important role in mucosal defense against infection and neoplastic transformation. In this study, an immunohistochemical investigation was performed on the distribution of / and / TCRs among tumor-infiltrating lymphocytes. Thirteen patients with squamous cell carcinomas of the upper aerodigestive tract were studied, using monoclonal antibodies and an avidin-biotin-peroxidase technique. Most of the T-cells had an / TCR. Only 1.6% of the T-cells within the cancer tissue and 1.2% of the T-cells in the parenchyma adjacent to the cancer tissue expressed /gd TCRs. These results are consistent with the results of similar studies in bronchial and breast carcinomas. Biopsies from normal oral mucosa in nine healthy individuals showed that 1.3% of the T -cells within the epithelium and 1.0% of those in the lamina propria adjacent to the epithelium expressed / TCRs. Quantitatively the results do not support the theory that / T-cells play an important role in the immunological response against cancer tissue in the mucosa of the upper aerodigestive tract. The functional role of these cells in the mucosa and in response to carcinomas is, however, still uncertain. 相似文献
108.
Pam McGrath Carla Patterson Patsy Yates Sue Treloar Brian Oldenburg Colleen Loos 《The Australian journal of rural health》1999,7(1):34-42
The findings presented in this paper are part of a research project designed to provide a preliminary indication of the support needs of postdiagnosis women with breast cancer in remote and isolated areas in Queensland. This discussion will present data that focuses on the women's expressed personal concerns. For participants in this research a diagnosis of breast cancer involves a confrontation with their own mortality and the possibility of a reduced life span. This is a definite life crisis, creating shock and needing considerable adjustment. Along with these generic issues the participants also articulated significant issues in relation to their experience as women in a rural setting. These concerns centred around worries about how their partner and families cope during their absences for treatment, the additional burden on the family of having to cope with running the property or farm during the participant's absence or illness, added financial strain brought about by the cost of travel for treatment, maintenance of properties during absences, and problems created by time off from properties or self-employment. These findings accord with other reports of health and welfare services for rural Australian and the generic literature on psycho-oncology studies of breast cancer. 相似文献
109.
Thomas Kelly 《Clinical & experimental metastasis》1999,17(1):67-72
Seprase is a serine protease that is integral to the plasma membrane and is overexpressed by invasive tumor cells (Piñeiro-Sánchez et al., J Biol Chem 1997; 272: 7595–601; Monsky et al., Cancer Res 1994; 54: 5702–10). Seprase activity is most often assessed by zymography, which is not a quantitative assay. This study establishes a relatively simple and quantitative method for determining seprase activity. The degradation of a 3H-gelatin substrate is measured in the presence of 5 mM EDTA which inhibits matrix metalloproteinases but not seprase. The quantitative character of the assay was demonstrated using partially purified seprase from chicken embryos, a preparation that lacks detectable matrix metalloproteinase activity. In this assay, release of 3H-gelatin fragments is linear over time for 1.5 g/assay seprase concentration as well as for preparations concentrated or diluted by five fold (7.5 g/assay and 0.3 g/assay respectively). Additional experiments were performed to validate the quantification of seprase activity using the radiographic assay by comparing the results to zymography. Exposure to 22 or 37°C results in maximal seprase activity while exposure to 80 or 100°C completely abolishes seprase activity in both zymography and the radiographic assay. Exposure to 60°C abolished seprase activity as judged by zymography, but about 50% gelatinase activity was observed using the 3H-gelatin substrate. Immunopreciptiation with seprase-specific antibody specifically removed seprase and lowered the seprase activity remaining in the extracts as judged by both assays. Investigation of the seprase that was partially purified from human breast cancer tissue revealed that its specific activity (cpm gelatin fragments released/ {mg protein×h}) is five times greater than that of seprase purified from chicken embryos. This assay will be useful for determining the seprase activity in extracts of tumor tissues and cells as well as for identifying inhibitors of seprase. 相似文献
110.
目的观察乳腺良恶性病变中纤维连接蛋白(FN)的分布,探讨它与乳腺癌分化、浸润、转移的关系。方法应用免疫组织化学方法,对乳腺良恶性病变纤维连接蛋白进行半定量研究。结果乳腺癌及淋巴结转移细胞FN呈强阳性表达,而基膜FN及间质FN普遍减少甚至缺乏。结论细胞FN可能是乳腺癌的一个标记物,间质FN及基膜FN减少有利于乳腺癌浸润、转移。 相似文献