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21.
Shioiri T Kojima M Hosoki T Kitamura H Tanaka A Bando T Someya T 《Journal of affective disorders》2004,82(3):395-401
BACKGROUND: Although panic disorder (PD) is suggestive of autonomic nervous system dysfunction, especially in the cardiovascular autonomic system (CAS), the results in many previous studies are still controversial. Using a new physiological index which could well reflect emotional reaction to visual stimuli (Yoshizawa, M., Sugita, N., Tanaka, A., Abe, K., Yambe, T., Nitta, S., 2001. Quantiatative Physioligical Evaluation of Three Dimensional Images. The Seventh International Conference on Virtual Systems and Multumedia, 25-27.), we studied momentary changes in the CAS in patients with PD during audiovisual stimulation (AS) as mental loading. METHODS: During AS, exposed to a video of imaginary experiences such as driving a motor vehicle or diving into the sea, blood pressure (BP) and heart rate (HR) were measured in 12 remitted patients with PD and 19 age- and sex-matched normal controls (NC). We used the maximum cross-correlation coefficient (rho(max)) from the BP to the HR, whose frequency components were limited to around 0.1 Hz. RESULTS: The rho(max) was an available index which could detect the momentary changes in the CAS during AS in both groups. The two-way ANOVA disclosed significant group and time effects on the rho(max). The momentary response to emotional stimuli in the PD patients was slower than that in the NC subjects. LIMITATIONS: Antidepressants have a potential impact on the autonomic variables in this study. CONCLUSIONS: These findings suggest that there may be a dysfunction of the CAS in remitted PD patients and that the dysfunction may be one of the trait markers of PD. To confirm these findings, however, further studies with a large sample size are required. 相似文献
22.
Horie R Watanabe T Ito K Morisita Y Watanabe M Ishida T Higashihara M Kadin M Watanabe T 《The American journal of pathology》2002,160(5):1647-1654
We previously reported that ligand-independent signaling by highly expressed CD30 in Hodgkin-Reed-Sternberg (H-RS) cells is responsible for constitutive activation of NF-kappa B. In the present study, we characterize the intracellular localization of tumor necrosis factor (TNF) receptor associated factor (TRAF) proteins in H-RS cells. Confocal immunofluorescence microscopy of cell lines derived from H-RS cells and HEK293 transformants highly expressing CD30 revealed aggregation of TRAF2 and TRAF5 in the cytoplasm as well as clustering near the cell membrane. In contrast, TRAF proteins were diffusely distributed in the cytoplasm in cell lines unrelated to Hodgkin's disease (HD) and control HEK293 cells. Furthermore, the same intracellular distribution of TRAF proteins was demonstrated in H-RS cells of lymph nodes of HD, but not in lymphoma cells in lymph nodes of non-Hodgkin's lymphoma. Dominant-negative TRAF2 and TRAF5 suppressed cytoplasmic aggregation along with constitutive NF-kappa B activation in H-RS cell lines. Confocal immunofluorescence microscopy also revealed co-localization of IKK alpha, NIK, and I kappa B alpha with aggregated TRAF proteins in H-RS cell lines. These results suggest involvement of TRAF protein aggregation in the signaling process of highly expressed CD30 and suggest they function as scaffolding proteins. Thus, cytoplasmic aggregation of TRAF proteins appears to reflect constitutive CD30 signaling which is characteristic of H-RS cells. 相似文献
23.
Kusama T Hatama K Saito K Kizawa Y Murakami H 《The Japanese journal of physiology》2000,50(4):429-435
In a previous study, we showed that the protein kinase C (PKC) activator 4beta-phorbol 12-myristate 13-acetate (PMA) inhibited the gamma-aminobutyric acid (GABA)-gated currents in Xenopus oocytes expressing human rho1 GABA(C) receptors. To investigate whether the inhibition of currents was due to a decrease in efficacy or in the potency of rho1 GABA(C) receptor, concentration-response curves for GABA were compared before and after PMA treatment. The EC50 concentrations of GABA obtained during the maximally inhibited period were not statistically different from the concentrations obtained before PMA treatment (1.74 +/- 0.33 and 1.45 +/- 0.28 microM, respectively). These results indicate that the inhibition depends on a change in number or conductance of active receptor channels, but not on a change in affinity for GABA. To allow histochemical detection of rho1 GABA(C) receptors, we constructed a receptor tagged at the C-terminal position with human c-myc epitope. Electrophysiologically, the tagged receptors showed almost the same sensitivities for GABA and PMA as those of wild-type rho1 GABA(C) receptors. Immunohistochemistry with anti-myc antibody detected a dense concentration of tagged receptors at the surface area of Xenopus oocytes. Transient exposure to PMA reduced the density of immunofluorescence at the surface area and increased it in the subsurface area. These results suggest that the stimulation of protein kinase C leads to internalization of rho1 GABA(C) receptors expressed in Xenopus oocytes. 相似文献
24.
25.
The effects of cimetidine on the growth of a human ovarian cancer cell line inoculated into BALB/c nude mice were examined. The cell line, designated "KK," was derived from a cystadenocarcinoma of the ovary. The passage number was about 40, and its tumorigenicity in nude mice was 100% even when 10(5) cells were inoculated. About 2 weeks after inoculation, the KK cells formed palpable tumors, and the tumor volume reached 2.29 cm3 on day 36. Conversely, the nude mice given cimetidine (100 mg/kg/day) orally with drinking water had about one-third the tumor volume (0.81 cm3) of that in untreated nude mice on day 36. The natural killer activity against the YAC-1 (a T-cell lymphoma) cell line in spleen cells of the nude mice challenged with human xenogeneic tumor (KK cell line) was not affected by treatment with cimetidine while inhibiting the tumor growth. The capacity to lyse the KK cells did not exist in the spleen cells of nude mice challenged with the KK cell xenograft and not treated with cimetidine. The cimetidine-treated spleen cells acquired the capacity to lyse the KK cells on day 14. Thereafter, the capacity was maintained at the same level as long as cimetidine was administered, whereas that in untreated nude mice remained undetectable. 相似文献
26.
Sonoo Mizuiri Yoshiko Nishizawa Toshiki Doi Kazuomi Yamashita Kenichiro Shigemoto Koji Usui Michiko Arita Takayuki Naito Shigehiro Doi Takao Masaki 《Renal failure》2021,43(1):371
ObjectiveA high coronary artery calcification score (CACS) may be associated with high mortality in patients undergoing hemodialysis (HD). Recently, effects of iron on vascular smooth muscle cell calcification have been described. We aimed to investigate the relationships between iron, CACS, and mortality in HD patients.MethodsWe studied 173 consecutive patients who were undergoing maintenance HD. Laboratory data and Agatston’s CACS were obtained at baseline for two groups of patients: those with CACS ≥400 (n = 109) and those with CACS <400 (n = 64). Logistic regression analyses for CACS ≥400 and Cox proportional hazard analyses for mortality were conducted.ResultsThe median (interquartile range) age and duration of dialysis of the participants were 67 (60–75) years and 73 (37–138) months, respectively. Serum iron (Fe) and transferrin saturation (TSAT) levels were significantly lower in participants with CACS ≥400 than in those with CACS <400, although the serum ferritin concentration did not differ between the groups. TSAT ≥21% was significantly associated with CACS ≥400 (odds ratio 0.46, p<0.05). TSAT ≥17%, Fe ≥63 µg/dL, and ferritin ≥200 ng/mL appear to protect against 5-year all-cause mortality in HD patients, independent of conventional risk factors of all-cause mortality (p < 0.05).ConclusionWe have identified associations between iron, CACS, and mortality in HD patients. Lower TSAT was found to be an independent predictor of CACS ≥400, and iron deficiency (low TSAT, iron, or ferritin) was a significant predictor of 5-year all-cause mortality in HD patients. 相似文献
27.
Mochizuki Toshio Muto Satoru Miyake Masateru Tanaka Toshiki Wang Wenchyi 《Clinical and experimental nephrology》2021,25(11):1231-1239
Clinical and Experimental Nephrology - Tolvaptan is a vasopressin type 2 receptor antagonist and has been used to treat autosomal dominant polycystic kidney disease (ADPKD) since 2014. There has... 相似文献
28.
29.
Masayuki Takeda Yasushi Katayama Toshiki Tsutsui Hitoshi Takahashi Kazuhide Saito Shotaro Sato Tatsuhiko Yuasa Takeo Kuwabara 《Urological research》1993,21(3):193-197
Summary
31P nuclear magnetic resonance (NMR) spectroscopy of the in situ rat kidney was performed by a surface coil method, and the effects of ischemia and furosemide infusion were assessed.31P NMR spectra of the kidney subjected to 30 min of ischemia returned completely to the pre-ischemic level after 60 min of reperfusion. But the31P NMR spectra after 60 min of ischemia did not recover, even after 120 min of reperfusion. Levels of -ATP and inorganic phosphate (Pi) decreased and the chemical shift of Pi increased after intravenous infusion of furosemide. This increase in chemical shift might signal an alkalotic change in intracellular pH. Furosemide infusion prior to ischemia is thought to protect the kidney from injury induced by 60 min of warm ischemia. The chemical shift of Pi returned to the pre-ischemic level earlier than -ATP and Pi. In conclusion, according to the findings of31P NMR spectroscopy, furosemide infusion prior to ischemia may be effective in protecting the kidney against ischemic injury. But the change in Pi peak and the causes of the dissociation of Pi and -ATP should be examined further. 相似文献
30.
Lin Y Kawamura T Anno T Ichihara Y Ohta T Saito M Fujioka Y Kimura M Okada T Kuwayama Y Wakai K Ohno Y 《Environmental health and preventive medicine》1999,4(3):117-121
It is well known that physical exercise can reduce coronary risk factors. But how an aerobic exercise modifies coronary risk
factors in relation to severity and physical fitness is still controversial.
Fifty-four middle-aged women (mean age, 55 years) completed a 6-month on-site and home-based anaerobic threshold-level exercise
program. The changes in coronary risk factor profiles were observed during the pre-intervention and intervention periods.
Before the intervention (during control period), most coronary risk factors showed a rather unfavorable trend. After the program,
their mean body weight decreased from 56.7 to 55.7 kg (p>0.05) and the proportion of body fat from 30.9 to 27.9% (p>0.05)
without any reduction in lean body mass. Systolic blood pressure (SBP) decreased from 129.0 to 125.0 mm Hg (p>0.05) and diastolic
blood pressure from 79.5 to 76.6 mm Hg (p>0.05). Fasting plasma glucose (FPG) declined from 109.6 to 103.4 mg/dl (p>0.05).
Changes in SBP and FPG were most remarkable in their respective worst tertile. Serum lipids improved only modestly. Maximum
oxygen uptake increased from 23.6 to 26.1 ml/kg/min (p>0.01). However, no significant correlations were found between changes
in coronary risk factors and those in physical fitness. We conclude that the 6-month aerobic exercise program would modify
women’s coronary risk factors depending on their initial values, probably independently of the changes in physical fitness. 相似文献