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991.
The objectives of this paper were to evaluate the effects of colour measuring modes [specular component excluded (SCE) versus specular component included (SCI)] and the standard light source (C, A or D65) on the colour of shade guides. After the labial part of shade tabs of two shade guides (Vita and Chromascop) was polished flat up to no. 2400 silicone carbide paper, the colour was measured according to the International Commission on Illumination (CIE)L*a*b* colour scale on a spectrophotometer. In both shade guides, all the average CIE L* values of each shade series, and most of CIE b* values were different depending on the measuring mode (P < 0.01). However, there was no difference in CIE a* values depending on the measuring mode. Colour difference (deltaE*) between the values measured with SCE mode and with SCI mode was 3.21-6.50 in Vita shade guide, 3.22-5.47 in Chromascop shade guide. DeltaE* caused by the difference in light source was very small in Vita shade guide regardless of the measuring mode. In the Vita shade guide, the shade series (A-D) was negatively correlated with CIE L* and CIE a* values measured with SCE mode. In the Chromascop shade guide, the shade series (100-500) was negatively correlated with CIE L* value measured with SCI mode. 相似文献
992.
Yoon JH Kim J Park C 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2002,94(6):741-745
Congenital immature teratoma of the tongue is a very rare form of extragonadal teratoma. We report an infant autopsy case of a huge congenital immature teratoma protruding from the tongue of a female infant born to a woman at 28 weeks' gestation of her first pregnancy. The mass obstructed the infant's mouth and produced hydroamnios. Maternal alpha-fetoprotein serum level was elevated and the infant's tumor was identified before birth by ultrasonography. The pregnancy was terminated by cesarean section. 相似文献
993.
Long-term treatment with ramipril attenuates renal osteopontin expression in diabetic rats 总被引:17,自引:0,他引:17
Li C Yang CW Park CW Ahn HJ Kim WY Yoon KH Suh SH Lim SW Cha JH Kim YS Kim J Chang YS Bang BK 《Kidney international》2003,63(2):454-463
BACKGROUND: Osteopontin (OPN) mediates progressive renal injury in various renal diseases by attracting macrophages, and its expression is regulated by the renin-angiotensin system (RAS). We studied the association between OPN expression and tubulointerstitial injury, and investigated the effect of ramipril on OPN expression in an animal model of non-insulin-dependent diabetes mellitus (NIDDM): Otsuka Long-Evans Tokushima Fatty (OLETF) rats. METHODS: Control (Long-Evans Tokushima Otsuka, LETO) and diabetic (OLETF) rats were treated with ramipril (3 mg/kg in drinking water) or vehicle for nine months, starting at 20 weeks of age. Systolic blood pressure, body weight, urinary protein excretion and oral glucose tolerance tests (OGTT) were monitored periodically. Renal function, histology (glomerulosclerosis, tubulointerstitial fibrosis, and ED-1-positive cells as a measure of macrophage infiltration), and expressions of OPN and transforming growth factor-beta1 (TGF-beta1) were evaluated at the end of the study. RESULTS: Compared with the LETO rats, OLETF rats showed declines in creatinine clearance rate, increases in urinary protein excretion and systolic blood pressure, and development of glomerulosclerosis, tubulointerstitial fibrosis, and inflammatory cell infiltration (all P < 0.05). Blocking angiotensin II with ramipril significantly improved all of these parameters (all P < 0.01). At the molecular level, expressions of OPN and TGF-beta1 were up-regulated in the OLETF rats, and were markedly suppressed following ramipril treatment. The sites of strong OPN mRNA and protein expressions were localized to areas of renal injury. Of note, the expression of OPN mRNA was strongly correlated with the number of ED-1-positive cells (r = 0.560, P = 0.01) and the tubulointerstitial fibrosis score (r = 0.500, P < 0.05). CONCLUSIONS: Up-regulation of OPN expression may play a role in tubulointerstitial injury associated with diabetic nephropathy, and blockade of the RAS by ramipril may confer renoprotection by decreasing OPN expression in non-insulin-dependent diabetic nephropathy. 相似文献
994.
Malunion of femoral head fractures has been rarely reported. We report on three cases of malunion of the femoral head, which were treated by partial ostectomy. All patients were involved in traffic accidents and had a posterior fracture-dislocation of the hip. The types of femoral head fractures were Pipkin type I with inferomedial fracture fragment in all cases. Initially, they were treated by closed reduction and skeletal traction for between 6 and 8 weeks. The patients were then transferred to our hospital; the chief complaint was of limited hip motion. A protruding bony mass limiting the hip motion was resected in all cases. The Smith-Petersen approach was used in all cases. The malunion sites were located distally to the original fracture site in all cases. Full weight bearing was permitted, and a range of motion exercises was started postoperatively. Excellent results were obtained with almost complete restoration of hip motion without pain. In the follow-up radiographs, there were no cases of avascular necrosis. 相似文献
995.
Metastasis to regional lymph nodes in patients with esophageal squamous cell carcinoma: CT versus FDG PET for presurgical detection prospective study 总被引:24,自引:0,他引:24
PURPOSE: To prospectively compare the accuracy of fluorine 18 fluorodeoxyglucose (FDG) positron emission tomography (PET) and computed tomography (CT) for detection of primary tumor and metastasis to individual lymph node groups and for nodal staging. MATERIALS AND METHODS: From February 2000 to July 2001, 81 patients with squamous cell carcinoma of the esophagus (78 men and three women; age range, 31-90 years; mean age, 63 years) underwent CT and FDG PET before esophagectomy and lymph node dissection. During surgery, all visible and palpable lymph nodes in the surgical fields were removed. The accuracies of CT and FDG PET for depiction of metastasis to lymph nodes were compared. RESULTS: For depiction of malignant nodal groups in each lymph node group, the sensitivity, specificity, and accuracy, respectively, of CT were 11% (11 of 96 nodal groups), 95% (553 of 581), and 83% (564 of 677), whereas those of FDG PET were 30% (29 of 96), 90% (525 of 581), and 82% (554 of 677) (P values: < .001, .009, and .382, respectively). Twenty-eight false-positive interpretations were rendered at CT in evaluations of 11 mediastinal, four hilar, and 13 abdominal nodal groups, and 56 false-positive interpretations were rendered at FDG PET in evaluations of 23 mediastinal, 32 hilar, and one abdominal nodal group. CONCLUSION: FDG PET is more sensitive than CT for depicting nodal metastases in patients with squamous cell carcinoma of the esophagus. FDG PET is slightly less specific than CT for depicting metastases, but the difference in specificity between the two modalities is statistically significant. Both FDG PET and CT have low sensitivity for depicting nodal metastasis. The relatively low specificity of FDG PET for depiction of nodal metastasis compared with that of CT is caused mainly by a high rate of false-positive hilar node interpretations. 相似文献
996.
Transcatheter arterial chemoembolization with paclitaxel-lipiodol solution in rabbit VX2 liver tumor 总被引:17,自引:0,他引:17
PURPOSE: To evaluate the antitumor effects of transcatheter arterial chemoembolization (TACE) with a solution of an anticancer drug (Paclitaxel; Bristol-Myers Squibb, Princeton, NJ) and iodized oil (Lipiodol; Laboratoire Gurerbet, Aulnay-Sous-Bois, France) (hereafter, the solution), as well as intratumor concentration and hepatotoxicity, in experimentally induced liver tumor. MATERIALS AND METHODS: VX2 carcinoma was grown in livers of 30 rabbits. In 18 rabbits, TACE was performed with the high-dose solution (4 mg anticancer drug and 0.4 mL iodized oil, n = 6), the low-dose solution (1 mg anticancer drug and 0.4 mL iodized oil, n = 6), or iodized oil alone (0.4 mL, n = 6) in a control group. One week later, the growth ratio and residual viable proportion of the tumors were calculated on the basis of findings at spiral computed tomography and histopathologic examination. Hepatic and hematologic toxicities were evaluated by means of biochemical analysis. Differences between the three groups were statistically assessed with the Kruskal-Wallace and Mann-Whitney U tests. The remaining 12 animals were treated with the high-dose solution and serially sacrificed for clarification of chronologic change of concentration of the anticancer drug in liver tissues. RESULTS: Growth ratios and residual viable proportions of the tumors were significantly lower in the solution groups (high dose, 3.3% +/- 6.2 [mean +/- SD] and 2.8% +/- 3.6, respectively; low dose, 18.7% +/- 7.4 and 12.7% +/- 6.1, respectively) than in the control group (68.3% +/- 12.7 and 31.1% +/- 8.8, respectively) (P <.05). Hepatotoxicity was transient in all but one rabbit, which died 2 days after TACE with substantial biochemical changes. The anticancer drug accumulated in tumor where the concentration peaked at day 3 and returned to levels comparable to those for normal hepatic parenchyma at 7 days after TACE. CONCLUSION: TACE with the Paclitaxel-Lipiodol solution has dose-dependent antitumor effects without major toxicities in VX2 liver tumor. 相似文献
997.
Goodwin SC Yoon HC Chen G Abdel-Sayed P Costantino MM Bonilla SM Nishimura E 《Cardiovascular and interventional radiology》2003,26(2):158-167
The objective of this study was to evaluate the
efficacy of heparin-polymer-coated intravascular stents in the
reduction of vessel stenosis. Three types of coatings for Palmaz stents
were tested: 1) heparin covalently bound to a polyethylene oxide
(Hp-PEO) tether; 2) heparin copolymerized with ethylene vinyl acetate
(Hp-Elvax) and 3) Elvax alone. Polymer-coated stents and uncoated
controls were deployed in the external iliac arteries following
endothelial injury in 18 swine. The animals were maintained on an
atherogenic diet and examined by angiography at 6 and 12 weeks. The
stented segments were then harvested for histopathologic analysis. Both
types of heparin-coated stents resulted in increased luminal narrowing
as compared to the contralateral uncoated stents. At 6 weeks, average
luminal stenosis was 48% for Hp-PEO stents vs 35% for uncoated stents
(p < 0.05). At 12 weeks, average luminal
stenosis was 36% for Hp-PEO stents vs 26% for uncoated stents
(p = NS). For Hp-Elvax stents, the average
stenosis was 58% vs 33% for uncoated controls (p <
0.05) at 6 weeks and 47% vs 19% for uncoated controls
(p < 0.05) at 12 weeks. There was no
significant difference between Hp-Elvax stents and Elvax stents
(p = NS). Increased luminal narrowing in coated
stents was primarily secondary to a marked inflammatory response.
Heparin-polyethylene oxide and heparin-ethylene vinyl acetate-coated
stents resulted in increased luminal narrowing as compared with
uncoated stents, due to a marked inflammatory response. 相似文献
998.
BACKGROUND: Although spinal cannabinoid receptor agonist (WIN 55,212-2) has been shown to encounter various models of pain, the role of two subtypes of cannabinoid receptor for the antinociceptive effect of cannabinoids has not been investigated at the spinal level. Spinal alpha 2 receptor agonist (clonidine) and cholinesterase inhibitor (neostigmine) are also active in the modulation of nociception. The authors examined the properties of drug interaction after coadministration of WIN 55,212-2-clonidine, and intrathecal WIN 55,212-2-neostigmine, and further clarified the role of cannabinoid 1 and 2 receptors in cannabinoid-induced antinociception at the spinal level. METHODS: Catheters were inserted into the intrathecal space of male Sprague-Dawley rats, and 50 microl of 5% formalin solution was injected into the hind paw to evoke the pain. Isobolographic analysis was used for evaluation of pharmacologic interaction. RESULTS: Intrathecal 55,212-2, clonidine, and neostigmine dose-dependently suppressed the flinching observed during phase 1 and 2 in the formalin test. Isobolographic analysis revealed a synergistic interaction after intrathecal delivery of WIN 55,212-2-clonidine or WIN 55,212-2-neostigmine mixture in both phases. The antinociceptive effect of WIN 55,212-2 was antagonized by cannabinoid 1 receptor antagonist (AM 251) but not by cannabinoid 2 receptor antagonist (AM 630). No antinociceptive effect was seen after intrathecal administration of cannabinoid 2 receptor agonist (JWH 133). CONCLUSIONS: Intrathecal 55,212-2, clonidine, and neostigmine attenuate the facilitated state and acute pain. WIN 55,212-2 interacts synergistically with either clonidine or neostigmine. The antinociception of WIN 55,212-2 is mediated through the cannabinoid 1 receptor, but not the cannabinoid 2 receptor, at the spinal level. 相似文献
999.
The present study examined the effects of ambroxol and erdosteine, bronchial expectorants, on the cytokine synthesis, granule enzyme release, and free radical production in rat alveolar macrophages activated by lipopolysaccharide. Ambroxol and erdosteine significantly decreased the production of tumour necrosis factors-alpha, interleukin-1beta, and interleukin-6 in alveolar macrophages activated by lipopolysaccharide. These drugs significantly reduced the production of superoxide anion, hydrogen peroxide, and nitric oxide and the release of acid phosphatase and lysozyme in lipopolysaccharide-activated macrophages. Ambroxol and erdosteine showed no scavenging effect on superoxide anion and hydrogen peroxide, whereas both drugs effectively decomposed nitric oxide. The results show that ambroxol and erdosteine may inhibit the responses, including cytokine synthesis and free radical production, in rat alveolar macrophages activated by lipopolysaccharide. Unlike the production of reactive oxygen species, the inhibitory effect of ambroxol and erdosteine on the production of nitric oxide in lipopolysaccharide-activated alveolar macrophages may be accomplished by a scavenging action on the species and inhibition of the respiratory burst. 相似文献
1000.
Park DU Kim SB Yoon CS 《AIHA journal : a journal for the science of occupational and environmental health and safety》2003,64(6):837-841
Straight metalworking fluids (MWFs) were used to evaluate the potential for the loss of MWF mass from filters. Two methods were used to study the stability of MWF mass on filter media. The first was to spike known amounts of MWF onto polyvinyl chloride (PVC) filters, store the filters over silica gel desiccant, and take repeated gravimetric measurements of the filters at intervals of 1, 2, and 3 days. An MWF aerosol mist was generated in a test chamber and collected on PVC filters for the second experimental method. Additional clean air was drawn through a subset of filters (range 0.02-0.48 m(3)), which were then stored over silica gel prior to weighing. Losses due to desiccation were found in filters that had not been exposed to airflow, as well as for filters after aspiration. The losses occurring in spiked filters (range of mean 2.6-15.2%) were higher than those in collected filters (range 0.7-8.1%). The MWF aerosol mass collected on PVC filters decreased with the increasing volume of clean air passing through the filter. In a multiple regression model, to predict the loss of collected MWF due to desiccation, loading mass, fresh MWF, and air passing time of 10 min were significant predictors (p=.0001, R(2)=.374). In particular, only air passage of 10 min was significantly higher (2.13%) than the reference air passage (p=.0054). The investigators concluded that MWF aerosol collected on PVC filters may be lost to evaporation under conditions typical of shipment, storage, and desiccation of sample filters, and with airflow through the filter. 相似文献