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81.
82.
We report on the use of an instrument to measure exposure to stressors among 149 women presenting with their children for pediatric care at an urban primary care center. Overall, 38.3 percent of the women had significant levels of depressive symptoms; 71.4 percent of those in the "high stress" group had an adjusted prevalence odds ratio of 5.00 [95% CI = 2.12, 11.82]. We conclude that screening in the pediatric office is feasible for identifying women at high risk of becoming depressed. 相似文献
83.
Latent Pneumocystis carinii infection in commercial rat colonies: comparison of inductive immunosuppressants plus histopathology, PCR, and serology as detection methods 总被引:2,自引:0,他引:2 下载免费PDF全文
Weisbroth SH Geistfeld J Weisbroth SP Williams B Feldman SH Linke MJ Orr S Cushion MT 《Journal of clinical microbiology》1999,37(5):1441-1446
Histopathologic evaluation combined with a period of immunosuppression has been the standard procedure for detection of Pneumocystis carinii in commercial rat colonies. Variation in induction regimens and in the sensitivity of detection methods may result in underreporting of the presence of P. carinii in breeding colonies or delay its detection. In the present study, methylprednisolone and cyclophosphamide were evaluated for the ability to induce P. carinii infection in rats from an enzootically infected commercial barrier colony. The presence of P. carinii was detected by histopathologic methods and by amplification of a targeted region of the P. carinii thymidylate synthase gene by PCR over the 8-week study period. Sera taken from rats prior to either induction regimen were evaluated for the presence of P. carinii-specific antibodies by the immunoblotting technique. Few significant differences in ability to induce organism burden or in histopathology were observed between the two immunosuppressive regimens. However, a dramatic loss of weight over the study period was observed in rats treated with methylprednisolone but not in rats treated with cyclophosphamide. Although histopathologic changes attributable to P. carinii did not appear before 2 weeks with either immunosuppressant, the presence of the organism in these animals was detected by immunoblotting and PCR. Cyst scores and the intensities of the histopathologic lesions increased during the study period, but the number of rats exhibiting evidence of P. carinii infection did not change after week 3. These results suggest that use of the PCR method on postmortem lung tissue of rats without prior induction regimens or identification of anti-P. carinii antibodies in antemortem serum samples is a sufficiently sensitive method for detection of the presence of a P. carinii carrier state in rodent breeding colonies. 相似文献
84.
Laboratory infection of primates with Ascaris suum to provide a model of allergic bronchoconstriction 总被引:2,自引:1,他引:2 下载免费PDF全文
D I Pritchard R P Eady S T Harper D M Jackson T S Orr I M Richards S Trigg E Wells 《Clinical and experimental immunology》1983,54(2):469-476
Wild-caught non-human primates are naturally sensitive to Ascaris antigen and provide a useful model for studying atopic asthma. The present study was carried out to determine the effect of experimentally infecting home-bred macaques with the nematode Ascaris suum and hence provide an alternative for the naturally occurring model. Following oral infection with the parasite the animals developed a blood eosinophilia and specific antibodies to purified Ascaris antigen. These antibodies appeared to be of the IgE class as they could be detected by a radiometric assay using a radiolabelled antibody to human IgE. However, on further investigation, using the passive cutaneous anaphylaxis test, two classes of antibody were found, a heat labile (56 degrees C) and a heat stable antibody. Lung lavage cells taken from monkeys infected with Ascaris suum were shown to include cells morphologically characteristic of mast cells and released histamine when challenged in vitro with Ascaris antigen. Hence this model of immediate hypersensitivity provides a simple alternative to the less accessible natural model. 相似文献
85.
86.
Comparison of the chemotactic responsiveness of two fibrosarcoma subpopulations of differing malignancy. 总被引:1,自引:3,他引:1 下载免费PDF全文
F. W. Orr J. Varani J. Delikatny N. Jain P. A. Ward 《The American journal of pathology》1981,102(2):160-167
There are several points of similarity between the processes of cancer metastasis and inflammation. In both, cells circulate in the vasculature, arrest, and cross vessel walls, thereby entering the extravascular tissues. In vitro, leukocytes and some, but not all, tumor cells exhibit chemotaxis. Since the chemotactic response of leukocytes effect their transvascular migration, we propose that chemotactic responsiveness contributes to the ability of circulating tumor cells to localize in extravascular tissues. This study was done to seek a relationship between chemotactic responsiveness of tumor cells and their behavior in vivo. Two subpopulations of cells were isolated from a methylcholanthrene-induced fibrosarcoma. The two cell lines were compared with regard to their biologic behavior in vivo and their chemotactic responsiveness in vitro. In vivo one subpopulation was highly malignant. An injection of 2.0 x 10(5) cells into the footpad of syngeneic mice led to the development of primary tumors in 87% of the animals and lung metastases in 61% of the animals with primary tumors. This line demonstrated chemotaxis to a factor that behaved similarly in gel filtration and showed immunologic reactivity similar to that of a previously described tumor cell chemotactic factor derived from the fifth component of complement. In contrast, an injection of the same number of cells from the second subpopulation of fibrosarcoma cells led to the development of primary tumors in only 12% of syngeneic mice, and lung metastases did not occur. Neither this subpopulation nor normal embryonic fibroblasts demonstrated chemotactic responsiveness. We postulate that the ability of tumor cells to respond to specific chemotactic stimuli may be one of the many unique properties which distinguish malignant from benign tumor cells. This is the first report documenting the chemotactic responsiveness of non-ascites tumors and fibrosarcomas. 相似文献
87.
Characteristics of the chemotactic response of neoplastic cells to a factor derived from the fifth component of complement. 总被引:2,自引:6,他引:2 下载免费PDF全文
Chemotactic factors for malignant neoplastic cells can be generated from either the fifth component of complement or from leukotactic fractions obtained from zymosanactivated serum. Digestion of the fifth component of complement by trypsin initially produced leukotactic activity, but as digestion continues, leukotactic activity is lost and tumor cell chemotactic activity is generated. Separation of the leukotactic activity is lost and tumor cell chemotactic activity is generated. Separation of the leukotactic activity and tumor cell chemotactic activity can be accomplished by gel filtration or isoelectric focusing. Gel filtration indicates that the tumor cell chemotactic factor has a molecular weight of approximately 8000 daltons. Tumor cell chemotactic activity can be generated by trypsinizing the leukotactic fractions isolated by isoelectric focusing. The responses of cultured Walker tumor cells or of Walker ascites tumor cells are dose-dependent and truly chemotactic. Cells from a murine malignant lymphoma do not respond to the complement-derived chemotactic factor for tumor cells, indicating that not all malignant cells share this functional property. 相似文献
88.
Increased Sensitivity of Lymphocytes from Atopic Individuals to Histamine-Induced Suppression 总被引:4,自引:0,他引:4
Histamine depressed lymphocyte reactivity to phytohemagglutinin and, to a lesser degree, concanavalin A, when administered simultaneously with mitogen to lymphocyte cultures. Addition of histamine at later times to the cultures appeared to have a slightly enhancing effect on the lymphocyte response. Stimulation of lymphocytes with pokeweed mitogen was in some cases enhanced, even by high concentrations of histamine. Lymphocytes from atopic individuals were more sensitive to the inhibitory effect of histamine than lymphocytes from nonatopic individuals. The sensitivity appeared age-dependent, but within each age group histamine evoked significantly more suppression on lymphocytes from atopic than from nonatopic individuals. The possibility that the altered reactivity of lymphocytes to histamine, which appears to be associated with atopic allergy, is of pathogenic importance, is discussed, and a hypothesis for the development of atopic disease is proposed. 相似文献
89.
Predominance of null mutations in ataxia-telangiectasia 总被引:15,自引:4,他引:15
Gilad S; Khosravi R; Shkedy D; Uziel T; Ziv Y; Savitsky K; Rotman G; Smith S; Chessa L; Jorgensen TJ; Harnik R; Frydman M; Sanal O; Portnoi S; Goldwicz Z; Jaspers NG; Gatti RA; Lenoir G; Lavin MF; Tatsumi K; Wegner RD; Shiloh Y; Bar-Shira A 《Human molecular genetics》1996,5(4):433-439
Ataxia-telangiectasia (A-T) is an autosomal recessive disorder involving
cerebellar degeneration, immunodeficiency, chromosomal instability,
radiosensitivity and cancer predisposition. The responsible gene, ATM, was
recently identified by positional cloning and found to encode a putative
350 kDa protein with a Pl 3-kinase-like domain, presumably involved in
mediating cell cycle arrest in response to radiation-induced DNA damage.
The nature and location of A-T mutations should provide insight into the
function of the ATM protein and the molecular basis of this pleiotropic
disease. Of 44 A-T mutations identified by us to date, 39 (89%) are
expected to inactivate the ATM protein by truncating it, by abolishing
correct initiation or termination of translation, or by deleting large
segments. Additional mutations are four smaller in-frame deletions and
insertions, and one substitution of a highly conserved amino acid at the Pl
3-kinase domain. The emerging profile of mutations causing A-T is thus
dominated by those expected to completely inactivate the ATM protein. ATM
mutations with milder effects may result in phenotypes related, but not
identical, to A-T.
相似文献
90.