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961.
Sequential Decrease in Tight Junctions as Revealed by 7H6 Tight Junction-associated Protein during Rat Hepatocarcinogenesis 总被引:1,自引:0,他引:1
Yun Zhong Katsuhiko Enomoto Hirotoshi Tobioka Yasuhiro Konishi Masaaki Satoh Michio Mori 《Cancer science》1994,85(4):351-356
A sequential decrease in the number of hepatocyte tight junctions during the course of rat hepatocarcinogenesis was demonstrated by immunohistochemistry with a new 7H6 monoclonal antibody generated in our laboratory. Semiqnantitative analysis by confocal laser scanning microscopy revealed that the expression of 7H6 antigen was reduced in hyperplastic foci, hyperplastic nodules and hepatocellular carcinomas (HCC) to 43%, 28% and 25%, respectively, compared to corresponding normal liver tissues. 7H6 antigen was scarce in HCC with a trabecular pattern, whereas it was expressed intensely at the apical and basolateral membrane of HCC with a glandular pattern. Immunoblot analysis of 7H6 expression in hepatocellular carcinomas showed a decrease roughly coincident with that shown by immunohistochemistry. These results indicated, for the first time, that tight junctions decrease progressively during carcinogenesis, leading to disruption of cellular polarity and cellular adhesiveness. 相似文献
962.
963.
Normal human pulmonary elastic fiber development and development in some pathological conditions were examined using elastic stains by light microscopy, electron microscopy, and immunohistochemistry. In normal development elastic fibers, composed mainly of microfibrils, first appeared around primitive bronchioles at 10 weeks of gestation. As they matured, their appearance became more amorphous, and they extended into the peripheral alveolar walls. Development of elastic fibers was retarded in the hypo-plastic lungs of the oligohydramnios syndrome, diaphragmatic hernia, and hydrops fetalis. Elastic development was also retarded in congenital pulmonary lymphangiectasia and in focal areas of lungs with pulmonary dysplasia. Distribution of well-developed elastic fibers was found around the dilated bronchioles and alveoli in cases of congenital cystic adenomatoid malformation and extralobar pulmonary sequestration. Elastic fibers were distributed irregularly and unevenly in the lungs of bronchopulmonary dysplasia and ventilated cases of Wilson Mikity syndrome. In addition, four very immature infants who had progressively deteriorating respiratory function showed an almost total lack of elastic fibers in their alveolar walls. 相似文献
964.
T Nakayama S Sonoda T Urano M Osano N Maehara K Sasaki E Hayatsu S Makino 《The Pediatric infectious disease journal》1992,11(2):72-77
In patients infected with Mycoplasma pneumoniae the development of interferon (IFN) was studied in nasopharyngeal secretions and sera. The production of IFN-gamma by lymphocytes was also investigated in response to M. pneumoniae antigen and mumps virus antigen. IFN-alpha was detected in 25 (61.0%) of 41 nasopharyngeal secretion samples and in 25 (59.5%) of 42 serum samples within 6 days after the onset of illness. IFN-alpha was significantly higher in nasopharyngeal secretions than in sera and a significant correlation was observed between the two. In most of the patients lymphocytes produced a larger amount of IFN-gamma in the convalescent stage than in the acute stage, when lymphocytes were stimulated with M. pneumoniae antigen. In some patients, however, lymphocytes did not produce IFN-gamma during the course of illness. Such lymphocytes, negative for IFN-gamma production in response to M. pneumoniae, produced IFN-gamma after the depletion of macrophages, and readdition of macrophages suppressed the production of IFN-gamma by lymphocytes. When lymphocytes were stimulated with heterogeneous antigen (mumps virus), they produced no IFN or a small amount of IFN in the acute stage of M. pneumoniae infection, and IFN production increased in the convalescent stage. Different mechanisms seem to work for homogeneous and heterogeneous antigens in the suppression of IFN production in M. pneumoniae infection. 相似文献
965.
Kojima M Wakai K Kawamura T Tamakoshi A Aoki R Lin Y Nakayama T Horibe H Aoki N Ohno Y 《Journal of epidemiology / Japan Epidemiological Association》2000,10(2):87-93
A population-based cohort study was conducted to assess the relationship between total mortality and self-reported sleep patterns as regards not only to sleep duration but also subjective sleep quality. A total of 5,322 inhabitants in Gifu Prefecture, Japan, completed a self-administered questionnaire on health status and lifestyles including habitual sleep patterns, and were followed-up for an average of 11.9 years. Relative risks were computed by using Cox proportional hazards models. Both longer and shorter sleep, compared to 7-8 hour-sleep, was related to significantly increased risk of total mortality in males (relative risk [RR] for > or = 10 hours = 1.94, and RR for < 7 hour = 1.90), but not in females. Females complaining of poor awakening state experienced a higher mortality risk compared to those who woke up normally (RR: 1.97). Males who usually fell asleep easily showed a marginally lower mortality risk compared to those who fell asleep normally (RR: 0.70). Female users of sleeping pills were at an elevated risk (RR: 1.89). These findings were almost unchanged after adjustment for sleep duration and other confounders. Poor self-reported quality of sleep seemed to be associated with an increased risk of mortality independently of sleep duration. 相似文献
966.
S Makino K Sasaki T Nakayama S Oka T Urano M Kimura R Kawana A M Yamamura 《American journal of diseases of children (1960)》1990,144(8):905-910
Trivalent virus vaccine, containing measles AIK-C strain, mumps Hoshino strain, and rubella Takahashi strain, was administered to a total of 1369 healthy children, 8 months to 18 years of age. For comparative study, monovalent vaccines of AIK-C strain and Hoshino strain were administered to 147 and 122 initially seronegative children, respectively. The clinical and serological responses following vaccination were analyzed. Among the recipients of the trivalent vaccine, 893 were initially seronegative to all three viruses. Inoculation induced sufficient serological responses: 99.7% for measles and rubella viruses and 96.3% for mumps virus. The incidence of febrile reaction (greater than or equal to 37.5 degrees C axillary temperature) was low, 15.9%, and a temperature of 39.0 degrees C or higher occurred in only 1.3% of the subjects. The seroconversion rate, magnitude of antibody titers, and incidence of clinical reactions following the trivalent vaccination were similar to those occurring after the monovalent measles vaccination. 相似文献
967.
Suppression of mixed lymphocyte reaction by cells of human first trimester pregnancy endometrium 总被引:2,自引:0,他引:2
In order to identify an immunological role for decidual tissue in pregnancy we have prepared single cell suspensions from the tissues of normal pregnant women and examined the effects of these cells on one-way mixed-lymphocyte reactions (MLR). The separated cells were heterogeneous, containing classical decidual cells, glandular epithelial cells, granular endometrial cells, macrophages and small lymphoid cells. [3H]Thymidine incorporation at day 6 of the MLR was suppressed by addition of the cells at the initiation of the cultures and the degree of suppression was inversely correlated to the gestational age of the decidual tissue, apparently through inhibition of the antigen recognition phase of the MLR. These findings support the view that the cells of the human first trimester pregnancy endometrium may play an important role in protecting the feto-placental unit from rejection, at least in the early phase of pregnancy. 相似文献
968.
M Ito H Katabuchi T Yoshimura K Matsui M Nakayama M Maeyama 《International journal of gynaecology and obstetrics》1985,23(5):395-398
We report a rare case of eclampsia which occurred during the 18th gestational week in the absence of hydatidiform disease or Rh isoimmunization. In spite of extensive examinations during pregnancy and postpartum, we were unable to find any underlying disease, and the patient returned to being normotensive and non-proteinuric postpartum. 相似文献
969.
Adrenomedullin in cultured human retinal pigment epithelial cells 总被引:13,自引:0,他引:13
Udono T Takahashi K Nakayama M Murakami O Durlu YK Tamai M Shibahara S 《Investigative ophthalmology & visual science》2000,41(7):1962-1970
PURPOSE: To determine whether adrenomedullin (ADM), a vasorelaxant peptide is produced and secreted by human retinal pigment epithelial (RPE) cells, whether ADM expression is regulated by inflammatory cytokines and a growth factor, and whether ADM has proliferative effects on these cells. METHODS: Production and secretion of ADM by cultured human RPE cells were examined by Northern blot analysis and radioimmunoassay. Regulation of the ADM expression by basic fibroblast growth factor, interferon (IFN)-gamma, tumor necrosis factor-alpha, interleukin (IL)1beta, or all-trans-retinoic acid was studied. In addition, proliferative effects of ADM on human RPE cells were examined by modified 3-(4,5-dimetylthiazol-2-yl)2,5-diphenyltetrazolium bromide (MTT) assay. RESULTS: ADM mRNA was expressed constitutively in all three human RPE cell lines (F-0202, D407, and ARPE-19) examined. Immunoreactive ADM was detected in the cultured media by radioimmunoassay. Sephadex G-50 column chromatography of the cultured medium showed a single peak eluting in the position of ADM-(1-52). Treatment with IFN-gamma or IL-beta increased ADM mRNA levels and immunoreactive-ADM levels in the medium in dose- and time-dependent manners in ARPE-19 cells. Exogenously added ADM increased the number of F-0202 cells and ARPE-19 cells, and the treatment with ADM antibody or ADM-(22-52) (an ADM antagonist) decreased it. CONCLUSIONS: Human RPE cells produced and secreted ADM. IFN-gamma and IL-1beta induced ADM expression in ARPE-19 cells. Furthermore, ADM stimulated proliferation of RPE cells. These results raise the possibility that ADM is related to the pathophysiology of some inflammatory and proliferative ocular diseases. 相似文献
970.
Kazushige Hayakawa Norio Mitsuhashi Masaya Furuta Yoshihiro Saito Yuko Nakayama Susumu Katano Tatsuya Ohno Hideo Niibe 《International journal of clinical oncology / Japan Society of Clinical Oncology》1996,1(1):13-17
Background From 1976 through 1989, 46 patients with stage IIIB non-small cell lung cancer (NSCLC) without malignant effusion were treated
with definitive radiation therapy (RT) at Gunma University Hospital.
Methods All patients were treated with 10 MV x-rays using antero posterior parallel opposed fields. The total dose ranged from 60
Gy to 70 Gy (mean dose; 66 Gy) with once daily standard fractionation.
Results The actuarial two and five-year survival rates of the entire group were 22% and 10% respectively with a median survival time
(MST) of 10 months. The survival of 18 patients with stage NO-2 disease was significantly better than the 28 patients with
stage N3 disease (MST 21 versus 9 months;P<0.05). There were no significant differences in survival based on age and sex. However, there was a borderline difference
in survival rates between patients with a performance status of 0–1 and those with a status of 2–3 (P=0.06). Three patients with squamous cell carcinoma were alive after 5 years and were without disease progression. No patients
with non-squamous cell carcinoma were free of disease after 5 years.
Conclusion These results provide support for the use of definitive RT to manage those patients with limited stage IIIB squamous cell
carcinoma not extending to N3 stage. 相似文献