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排序方式: 共有3273条查询结果,搜索用时 46 毫秒
41.
K Morikawa S Morikawa A Nakano F Oseko 《International journal of immunopharmacology》1989,11(8):905-913
Bestatin, an inhibitor of aminopeptidase B, was examined for its effect on B-cell activation. Small, dense B-cells from human tonsil samples were isolated by Percoll density gradients from non-rosetted (E-) cells and were used as target cells. Although bestatin was not cytotoxic towards B-cells, it inhibited the proliferative response of B-cells induced by SAC- or PMA-stimulation. The inhibition of cell proliferation by bestatin was manifested as cell arrest caused by the selective block of G1b to S phase transition. This inhibitory effect was prevented by the addition of B-cell growth factor (BCGF) or interleukin-2 (IL-2). The presence of BCGF or IL-2 at the initiation of the culture prevented the bestatin-mediated suppressive effect on B-cell proliferation. Bestatin also has a direct inhibitory effect on the differentiation of B-cells independent of its suppressive effect on B-cell proliferation, which was not relieved by T-cell help. Conversely, bestatin suppressed neither proliferation nor Ig secretion of human B lymphoblastoid cell lines, although aminopeptidase activities on the membrane of these cell lines were strongly inhibited by bestatin. These results indicated that bestatin selectively suppressed normal B-cell proliferation and differentiation. Although several studies have demonstrated that bestatin has immunopotentiating effects in tumor-bearing subjects, the above results indicated that the mechanism of immunopotentiation by bestatin is not a direct stimulatory effect on B-cells. 相似文献
42.
K Morikawa 《Rinsho byori. The Japanese journal of clinical pathology》1989,37(9):1013-1019
To examine granulocyte oxidative metabolism (GOM) quantitatively, we evaluated two methods, one for assaying luminol-dependent chemiluminescence (CL) and the other for changes in fluorescence by dichlorofluorescin (DCF). The CL assay was carried out using a lumiphotometer (TD-4000, Laboscience) after stimulating granulocytes in whole blood by n-formyl-methonyl-leucyl-phenylalanine (FMLP, 100 nmol/l) or by opsonized zymosan (OZ, 2 mg/ml). To reduce hemoglobin (Hb) interference, each sample was diluted with autologous plasma to a Hb concentration of 3 g/dl. The DCF assay was performed on whole blood samples (100 microliters) labeled with DCF (5 mumol/l) following stimulation by phorbol myristate acetate (PMA, 100 ng/ml). Changes in fluorescence were determined using a flow cytometer that gave the delta mean channel fluorescence intensity (DMCF) as an indicator of GOM. The coefficients of variance (CV) in within-run assays for the CL and the DCF were 10% and 5%, respectively. These CV-values were almost the same even when separated granulocytes as a test sample were used instead of whole blood. CL determined by FMLP stimulation in 27 renal failure patients on hemodialysis (HD), was significantly lower than that in 10 normal controls, but no difference was found in that determined by OZ stimulation. In HD patients, the DMCF values tended to increase in those at 15 min and the end of HD sessions compared to the value prior to HD. This suggested that the HD membrane and/or extracorporeal circulation stimulates GOM.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
43.
Kazushige Dobashi Kohtaro Asayama Hidemasa Hayashibe Afreen Munim Akira Kawaoi Masahiko Morikawa Shinpei Nakazawa 《Virchows Archiv : an international journal of pathology》1993,423(3):177-184
To determine the late gestational development of copper-zinc (CnZn) and manganese (Mn) superoxide dismutases (SOD) in human lung, immunohistochemical localization was performed for each SOD. The lung samples were taken from five aborted fetuses, four fetuses in which intrauterine death occurred, one full-term neonate, two premature infants with hyaline membrane disease and one premature infant with bronchopulmonary dysplasia (BPD). Morphometry was performed, and the percent area of positive staining was computed. The bronchial epithelium was intensely stained from the early stages of gestation (i.e. 17 weeks), while the staining intensity for both CuZnSOD and MnSOD in the peripheral airways increased gradually during lung development. The mean percent area of the staining for CuZnSOD and MnSOD from 16 to 38 weeks was increased 30-fold and 8-fold, respectively, and further increases were observed postnatally. CuZnSOD staining was markedly decreased in lungs with respiratory disorders. However, proliferating type II pneumocytes were intensely stained for MnSOD in the BPD lungs, making the staining area 3-fold larger than that in the control lungs. These results clearly depict age-related increases in staining for both CuZnSOD and MnSOD and an alteration in SOD distribution associated with neonatal respiratory disorders. 相似文献
44.
Two cell lines designated IC-KMS and D-KMS were established from human adenovirus type 12-induced tumors of C3Hf/OK mouse. The cell lines retained the characteristics of the original tumor i.e., production of numerous C-type and intracisternal A-type particles, integration of Ad12 E1 region DNA and amplification of the myc gene family. Chromosomal analysis revealed chromosome aberrations in both IC-KMS and D-KMS cells. The modal chromosome number of IC-KMS cells was 54 and that of D-KMS cells was 48. Metacentric chromosomes and minichromosomes were found. Trisomy of chromosome 3, 7 and 12 was seen frequently in D-KMS cells. Although DNA aneuploidy was revealed by flow cytometry, the DNA indices of these cells showed no relation to the copy number of integrated Ad12 DNA. These cells have been propagated by serial culture during the past 17 months. Production of endogenous virus particles is a unique characteristic of IC-KMS and D-KMS cells. These cell lines would be useful materials for examining the contribution of Ad12 carcinogenesis to activation of endogenous virus particles, and also the correlation between Ad12 carcinogenesis and cancer-related genes. 相似文献
45.
46.
Makoto Nagasaki Takayuki Harada Ikuko Torii Akinobu Nakano Hiroshi Furuya Junichi Tanaka Kanji Hirai Shigeru Morikawa 《Pathology international》1994,44(12):850-856
A case of acquired immunodeficiency syndrome (AIDS) with preceding aplastic anemia is reported. The patient was a 36 year old female who had been diagnosed as having aplastic anemia 10 years before and thereafter had received multiple transfusions. Human immunodeficiency virus (HIV)-seropositivity was revealed 10 months prior to her death, but no particular clinical signs indicating HIV infection, pre-AIDS or onset of AIDS were recognized before serological diagnosis, although the slow progression of leukopenia was noted along with thrombocytopenia. Her general condition deteriorated during the last 10 months accompanied by an acute decrease In the CD4/CD8 ratio. Autopsy revealed full-blown AIDS: systemic aspergillosis, progressive multifocal leukoencephalopathy, Epstein-Barr virus-related B cell lymphoma arising in the diaphragm and severe lymphocyte depletion in the lymph nodes and spleen. Markedly hypo-plastic bone marrow was considered to be primarily attributable to the aplastic anemia but the affection of AIDS was not excluded. The possible transmission route of HIV and the effect of the preceding aplastic anemia on the infection and clinical course of AIDS are discussed. 相似文献
47.
In Cambodia, nearly half of pregnant women attend antenatal care (ANC), which is an entry point of services for prevention
of mother-to-child transmission of HIV (PMTCT). However, most of ANC services are provided in health centres or fields, where
laboratory services by technicians are not available. In this study, those voluntary confidential counselling and testing
(VCCT) counsellors involved in PMTCT were trained by experienced laboratory technicians in our centre on HIV testing using
Determine (Abbot Laboratories) HIV1/2 test kits through a half-day training course, which consisted of use of a pipette, how
to process whole blood samples, and how to read test result. The trained counsellors were midwives working for ANC and delivery
ward in our centre without any experience on laboratory works. The objective of this study was to assess the feasibility of
the training by evaluating the proficiency of the trained non-laboratory staffs. The trained counsellors withdrew blood sample
after pre-test counselling following ANC, and performed the rapid test. Laboratory technicians routinely did the same test
and returned reports of the test results to counsellors. Reports by the counsellors and the laboratory technicians were compared,
and discordant reports in two groups were re-tested with the same rapid test kit using the same blood sample. Cause of discordance
was detected in discussion with both groups. Of 563 blood samples tested by six trained VCCT counsellors and three laboratory
technicians, 11 samples (2.0%) were reported positive in each group, however four discordant reports (0.7%) between the groups
were observed, in which two positive reports and two negative reports by the counsellors were negative and positive by the
laboratory technicians, respectively. Further investigation confirmed that all the reports by the counsellors were correct,
and that human error in writing reports in the laboratory was a cause of these discordant reports. These findings lead us
the conclusion that the half-day training using the rapid and simple test was feasible for non-laboratory staffs to attain
enough proficiency to implement VCCT services for PMTCT in resource-limited settings, and that human error was more likely
to occur in laboratory before giving reports to counsellors. 相似文献
48.
Kanji Ohiwa Takayuki Harada Shigeru Morikawa Teruhisa Nakamura 《Pathology international》1994,44(8):635-644
The distribution of carcinoembryonic antigen (CEA) in human gastric adenocarcinoma cell lines (HPE-GAC-3 cells and HPE-GAC-2 cells) was determined immunohistochemically by indirect peroxidase-labeled antibody method at the light and electron microscopic levels. In GAC-3 cells that proliferated as non-adherent single cells, CEA was located in the perinuclear spaces, the endoplasmic reticulum, Golgi apparatus, vesicles, multivesicular body (MVB) and entire plasma membrane. Membrane CEA was shown to be internalized into MVB in GAC-3 cells. In GAC-2 cells that form an acinus, CEA was predominantly present along the microvilli of the lumina) surface and in glycocalyceal bodies, the vesicles which bud from the microvilli into the lumen. These results suggest that in poorly differentiated cancer cells CEA is transported over the entire cell surface, retained on the membrane and accumulated Into the cell by way of the MVB, but in well differentiated cancer cells the newly synthesized CEA is rapidly and predominantly transported to the luminal surface and rapidly released from the membrane into the lumen by way of the glycocalyceal body. 相似文献
49.
High NK cell activity in early pregnancy correlates with subsequent abortion with normal chromosomes in women with recurrent abortion 总被引:12,自引:0,他引:12
Yamada H Kato EH Kobashi G Ebina Y Shimada S Morikawa M Sakuragi N Fujimoto S 《American journal of reproductive immunology (New York, N.Y. : 1989)》2001,46(2):132-136
PROBLEM: The aim of this study was to assess the role of natural killer (NK) cells in pregnant women with a history of recurrent spontaneous abortion (RSA). METHOD OF STUDY: Consecutive 66 pregnant women with a history of RSA were prospectively assessed for peripheral NK cell activity, percentage of the NK cell subsets, and subsequent pregnancy outcome. RESULTS: NK cell activity in women with subsequent live birth (group I) at 4-5 gestational weeks (GW) (mean +/- SD, 32.5 +/- 12.31%) significantly decreased at 6-7 GW (28.1 +/- 12.1%) and at 8 9 GW (28.0 +/- 11.8%). NK cell activity in women with subsequent abortion with normal chromosomes (group II) at 6 7 GW (41.2 +/- 19.0%) was significantly higher than that in group I women, while NK cell activity at 6-7 GW in women with subsequent abortion with abnormal chromosomes (group III) was the same as the level in group I women. CONCLUSIONS: High NK cell activity at 6-7 GW correlates with subsequent abortion with normal chromosomes. 相似文献
50.
Y Morikawa K Kuribayashi K Saito 《International archives of allergy and applied immunology》1989,90(2):130-136
We analyzed the conditions for in vivo toleration of delayed-type hypersensitivity (DTH). The intravenous injection of a high dose of keyhole-limpet hemocyanin (KLH) into BALB/c mice did not induce DTH in vivo, but the serum titers of the anti-KLH antibody were significantly elevated. This lack of DTH response was antigen-specific, and the intravenous injection of the antigen induced effector-phase suppressor T cells. The findings suggested that the lack of a DTH response brought about by the intravenous injection of a high dose of antigen was not immunological tolerance. Treatment with a high dose (250 mg/kg) of cyclophosphamide - but not a low dose (50 mg/kg) - enhanced the DTH, but suppressed antibody production. These results indicate that humoral immune response participate in the regulation of DTH. In addition, the transfer of serum or immunoglobulin from mice that were injected intravenously with a high dose of the antigen suppressed the DTH. We concluded that the antibodies regulate DTH in the antigen-specific manner. 相似文献