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991.
An alternative approach to quantifying and addressing inequity in healthcare provision: access to surgery for lung cancer in the east of England 下载免费PDF全文
STUDY OBJECTIVE: Equitable access to healthcare services should be monitored routinely. This study compares provision of surgery for non-small cell lung cancer in the east of England with incidence of non-small cell lung cancer. In addition to conventional comparisons, process control charts are used to identify areas in which access seems to be significantly different from average. DESIGN: Ecological comparison of surgery rates for non-small cell lung cancer between 1998 and 2000 and incidence of non-small cell lung cancer over the same time period. SETTING: Population of Norfolk, Suffolk, Cambridgeshire. PARTICIPANTS: The denominator was the resident population. Numerators were 4092 deaths from non-small cell lung cancer and 387 surgical procedures for lung cancer. MAIN RESULTS: Incidence of non-small cell lung cancer by primary care trust (PCT) does not correlate with surgical procedure rate, in men r = 0.37 (95% confidence intervals -0.14 to 0.72), in women r = 0.07 (95% confidence intervals -0.43 to 0.53). Control charts indicate that the surgery rate is significantly different from average in three PCTs, high in one and low in two others. The optimum surgery rate is unclear but raising it from 9% to a theoretical level of 15% would mean no PCTs have above average rates while six PCTs have rates that are significantly low. CONCLUSIONS: There does not seem to be equity of access to surgery for patients with non-small cell lung cancer in the east of England. Control charts can help both to identify areas where access is particularly high or low, and also to monitor performance against a theoretical optimum surgery rate. 相似文献
992.
Reduced basal nitric oxide bioavailability and platelet activation in young spontaneously hypertensive rats 总被引:1,自引:0,他引:1
Schäfer A Widder J Eigenthaler M Ertl G Bauersachs J 《Biochemical pharmacology》2004,67(12):2273-2279
OBJECTIVE: To investigate the role of basal nitric oxide (NO) bioavailability for platelet activation in young spontaneously hypertensive rats before onset of hypertension. Phosphorylation of the vasodilator-stimulated phosphoprotein (VASP) in platelets was used as a sensitive monitor of in vivo NO bioavailability. METHODS AND RESULTS: Whole blood samples were taken from 10-week-old Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR). In vivo surface-expression of P-selectin and platelet-binding of fibrinogen were assessed by flow cytometry. Platelet VASP-phosphorylation at its serine 239 (Ser239) and serine 157 (Ser157) residues was assessed using specific antibodies to determine NO bioavailability in vivo, and compared with endothelial vasomotor function. The increment in vascular tone following inhibition of NO-synthase in slightly preconstricted aortic rings was reduced indicating less NO formation under physiological stimulation (WKY 71.1+/-4.1%; SHR 57.8+/-2.4%, P<0.05). In vivo platelet VASP-phosphorylation was significantly reduced at both phosphorylation sites in SHR (mean fluorescence for Ser239: WKY: 15.2+/-0.6; SHR: 11.7+/-0.5, P<0.01; Ser157: WKY: 53.0+/-3.0; SHR: 35.0+/-3.5, P<0.05). Surface-expression of P-selectin and membrane-bound fibrinogen were significantly enhanced in SHR compared with WKY (P-selectin: WKY: 23.2+/-3.4; SHR 58.3+/-7.9, P<0.001; platelet-bound fibrinogen: WKY: 8.6+/-0.5; SHR: 13.5+/-1.1, P<0.001). In vitro preincubation of platelets with the NO donor sodium nitroprusside normalized platelet surface-expression of P-selectin in SHR. CONCLUSION: Using VASP-phosphorylation as a sensitive monitor of in vivo NO bioavailability, these data provide evidence that reduced vascular NO formation in vivo contributes to increased platelet activation in young SHR. 相似文献
993.
Critchley L Ding B Fok B Wang D Tomlinson B James A Thomas GN Critchley J 《European journal of pharmacology》2004,489(1-2):67-75
We have investigated the effects of the angiotensin II type 1 receptor antagonist candesartan, and the angiotensin II converting enzyme inhibitor ramipril, on catecholamine release from the anaesthetized dog's adrenal gland. These drugs were given systemically in low and high doses. The gland was stimulated electrically (0.5-12 Hz) and by angiotensin II infusion (40 ng/kg/min). Electrical stimulation resulted in frequency-dependent increases in catecholamine release. Candesartan (0.8, 4.0 mg/kg) and ramipril (0.125, 0.625 mg/kg) increased basal catecholamine release along with decreases in blood pressure. Both drugs diminished direct nerve stimulation-induced catecholamine release. When both drugs were combined, their inhibitory effect was slightly enhanced. Candesartan blocked catecholamine release induced by angiotensin II. Ramipril was not tested in this respect. The percentage of noradrenaline released during electrical stimulation of the gland remained constant and ranged from 14% to 22%. Both drugs appear to act by blocking local modulation of catecholamine release by the chromaffin cells. 相似文献
994.
Sanders JM Ghosh S Chan JM Meints G Wang H Raker AM Song Y Colantino A Burzynska A Kafarski P Morita CT Oldfield E 《Journal of medicinal chemistry》2004,47(2):375-384
gammadelta T cells are the first line of defense against many infectious organisms and are also involved in tumor cell surveillance and killing. They are stimulated by a broad range of small, phosphorus-containing antigens (phosphoantigens) as well as by the bisphosphonates commonly used in bone resorption therapy, such as pamidronate and risedronate. Here, we report the activation of gammadelta T cells by a broad range of bisphosphonates and develop a pharmacophore model for gammadelta T cell activation, in addition to using a comparative molecular similarity index analysis (CoMSIA) approach to make quantitative relationships between gammadelta T cell activation by bisphosphonates and their three-dimensional structures. The CoMSIA analyses yielded R(2) values of approximately 0.8-0.9 and q(2) values of approximately 0.5-0.6 for a training set of 45 compounds. Using an external test set, the activities (IC(50) values) of 16 compounds were predicted within a factor of 4.5, on average. The CoMSIA fields consisted of approximately 40% hydrophobic, approximately 40% electrostatic, and approximately 20% steric interactions. Since bisphosphonates are known to be potent, nanomolar inhibitors of the mevalonate/isoprene pathway enzyme farnesyl pyrophosphate synthase (FPPS), we also compared the pharmacophores for gammadelta T cell activation with those for FPPS inhibition, using the Catalyst program. The pharmacophores for gammadelta T cell activation and FPPS inhibition both consisted of two negative ionizable groups, a positive charge feature and an endocyclic carbon feature, all having very similar spatial dispositions. In addition, the CoMSIA fields were quite similar to those found for FPPS inhibition by bisphosphonates. The activities of the bisphosphonates in gammadelta T cell activation were highly correlated with their activities in FPPS inhibition: R = 0.88, p = 0.002, versus a human recombinant FPPS (N = 9 compounds); R = 0.82, p < 0.0001, for an expressed Leishmania major FPPS (N = 45 compounds). The bisphosphonate gammadelta T cell activation pharmacophore differs considerably, however, from that reported previously for gammadelta T cell activation by phosphoantigens (Gossman, W.; Oldfield, E. J. Med. Chem. 2002, 45, 4868-4874), suggesting different primary targets for the two classes of compounds. The ability to quite accurately predict the activity of bisphosphonates as gammadelta T cell activators by using 3D QSAR techniques can be expected to help facilitate the design of additional bisphosphonates for potential use in immunotherapy. 相似文献
995.
Elliott JH O'Brien D Leder K Kitchener S Schwartz E Weld L Brown GV Kain KC Torresi J;GeoSentinel Surveillance Network 《Journal of travel medicine》2004,11(4):213-219
BACKGROUND: Imported malaria is an important problem in nonendemic countries due to increasing travel to and immigration from malaria-endemic countries. Plasmodium vivax malaria is relatively common in travelers but there are few published data regarding the outcome of P. vivax malaria in this group. METHODS: We analyzed 209 cases of P. vivax malaria that were reported to the GeoSentinel network and the VIDS database, Royal Melbourne Hospital. Analyses were performed on data including demographics, pretravel encounter, antimalarial prophylaxis, exposure history, type of travel, countries of recent and past travel, clinical presentation, treatment, outcome and final diagnoses. RESULTS: The majority of patients were travelers (61%), followed by expatriates (13%) and recent immigrants or foreign visitors (12%). Recent travel to Oceania, sub-Saharan Africa, and South and Central America was significantly more likely to be associated with P. vivax malaria than travel to all other regions. The clinical presentation of P. vivax malaria acquired in the Pacific region is indistinguishable from infection with P. falciparum. The use of chloroquine prophylaxis did not prolong the incubation period. Relapse of infection was not infrequent, and the only significant predictor of relapse was travel to Papua New Guinea (PNG), regardless of primaquine dose. Travelers returning from PNG were eight times more likely to relapse after primaquine treatment compared to travelers with P. vivax malaria acquired elsewhere. CONCLUSIONS: We have presented details of the epidemiology, clinical presentation and management of infection with P. vivax malaria in travelers. P. vivax malaria is an important cause of morbidity in travelers, and relapse following primaquine treatment is especially problematic with P. vivax malaria acquired in PNG. 相似文献
996.
Sánchez Ruderisch H Aryee-Boi J Schwarz C Radenhausen M Tebbe B 《Skin pharmacology and physiology》2004,17(3):129-132
Shower PUVA is a new variant of photochemotherapy suitable for therapy of various skin disorders. Psoralen, e.g. trioxsalen-containing water recirculates in a closed shower system and wets the skin continuously. After showering, whole-body UVA irradiation (320-400 nm) is performed. In order to prove the equal distribution of photosensitivity in vivo minimal phototoxic dose (MPD) was determined in different skin areas of healthy individuals. Additionally, we investigated the accumulation of trioxsalen in psoriasis lesions under the conditions described by quantifying psoralen in scales collected after showering. In a randomized study 20 healthy volunteers (skin type I-III) took showers for 5 and 10 min in trioxsalen (0.27 mg/l)-containing water at 37 degrees C. Immediately afterwards, MPD was tested on the inside of the upper arms and on the buttocks by using a polychromator light source (315-400 nm). The applied UVA doses were 0.06-0.75 J/cm(2) with steps of 0.125 J/cm(2). MPD was evaluated after 72 h. Equal distribution of photosensitivity was defined as equal MPD on the insides of the upper arm and the buttocks (+/-0.125 J/cm(2)). Skin scales of 21 patients with psoriasis were collected by scratching after showering with trioxsalen-containing water (0.27 mg/l) for 5 min. For quantification of trioxsalen in the scales HPLC was performed. An equal distribution of photosensitivity was achieved in 70% (14/20) cases after 10-min showering in trioxsalen-containing water. Showering for 5 min only revealed a 30% (6/20) rate of equal distributed photosensitivity. After 10-min shower time MPD was 0.325 J/cm(2) (median; range: 0.06-0.625 J/cm(2)). The average amount of trioxsalen found in the scales was 2.03 ng/mg scales (range: 0.38-7.2 ng/mg). For shower PUVA using trioxsalen, 10 min shower time is recommended to achieve sufficient distribution of photosensitivity on the skin. Clinical efficacy of shower PUVA can be explained by skin accumulation of trioxsalen which enters from the aqueous phase into the upper skin layers in detectable amounts. This is the first report demonstrating the efficacy of shower PUVA which in short shower time allows an uptake of psoralen by the skin. 相似文献
997.
BACKGROUND: The objective of the current pilot project was to assess the efficacy of laser scanning cytometry (LSC) for DNA ploidy analysis of atypical urologic cytology specimens to enhance the distinction between benign and malignant changes. METHODS: Forty selected urologic cytology specimens that previously had been categorized as normal, atypical, or malignant were studied. Nuclear propidium iodide and fluorescence intensity measurements were converted to pixel values, which were used to create scattergrams that excluded debris and cell clusters from ploidy analysis, creating a gated (isolated) region of predominantly single cells for LSC ploidy analysis. Integral histograms then were created to show the number of cells present in diploid, tetraploid, and aneuploid peaks; these histograms also were used to assess DNA ploidy. RESULTS: Ten normal specimens, 10 malignant specimens, and 20 atypical specimens were examined to assess the efficacy of LSC ploidy analysis. Normal and malignant specimens generated reference histograms for comparison with the atypical specimens and exhibited 90% specificity and 100% sensitivity. Ten atypical aneuploid specimens had histogram and scattergram patterns similar to those produced by malignant specimens and, using the cytometer's relocation feature, the presence of atypical cells was confirmed in the aneuploid regions. CONCLUSIONS: The authors determined that DNA ploidy analysis of atypical urologic cytology specimens using LSC is a useful adjunct tool for identifying malignant specimens that lack sufficient cytologic criteria for diagnosis by light microscopy alone. However, LSC is time consuming and requires expensive equipment. 相似文献
998.
Immunochemotherapy with rituximab and temozolomide for central nervous system lymphomas 总被引:3,自引:0,他引:3
BACKGROUND: Methotrexate-based and alkylator-based chemotherapy regimens are associated with renal and bone marrow toxicities, which limit their use in patients with central nervous system (CNS) lymphomas. The authors report their experience with an immunochemotherapy regimen consisting of rituximab and temozolomide in patients with primary or metastatic CNS lymphoma. METHODS: Seven patients who had received rituximab and temozolomide were identified from the database of the brain tumor clinic at the authors' institution: three patients had developed recurrent primary CNS lymphoma (PCNSL), one patient had newly diagnosed PCNSL but had poor renal function, and three other patients with systemic non-Hodgkin lymphoma developed recurrent lymphoma in the brain only. Patients were scheduled to receive 4 cycles of induction rituximab on Day 1 and temozolomide on Days 1-5 of a 28-day cycle. Thereafter, their treatment included a total of up to 8 maintenance cycles of temozolomide alone on Days 1-5 of a 28-day cycle. A gadolinium-enhanced magnetic resonance image of the head was obtained after every two cycles of treatment. RESULTS: All patients received rituximab without toxicity. Of the 4 patients who received induction temozolomide at doses > 150 mg/m(2) daily on Days 1-5, 2 experienced Grade 2 leukopenia and thrombocytopenia. Five patients achieved a radiographic complete response, and two patients had partial responses after induction treatment. The median response duration was 6 months (range 3-12+ months), and the median survival was 8 months (range 3+-12+ months). CONCLUSIONS: Although median survival was short, immunochemotherapy with rituximab and temozolomide was well tolerated and exhibited efficacy in this elderly and heavily pretreated cohort. The data obtained in the current study suggest that the optimal induction dose combination consists of rituximab 375 mg/m(2) on Day 1 and temozolomide 150 mg/m(2) daily on Days 1-5. 相似文献
999.
RASSF1A interacts with microtubule-associated proteins and modulates microtubule dynamics 总被引:11,自引:0,他引:11
Dallol A Agathanggelou A Fenton SL Ahmed-Choudhury J Hesson L Vos MD Clark GJ Downward J Maher ER Latif F 《Cancer research》2004,64(12):4112-4116
The candidate tumor suppressor gene RASSF1A is inactivated in many types of adult and childhood cancers. However, the mechanisms by which RASSF1A exerts its tumor suppressive functions have yet to be elucidated. To this end, we performed a yeast two-hybrid screen to identify novel RASSF1A-interacting proteins in a human brain cDNA library. Seventy percent of interacting clones had homology to microtubule-associated proteins, including MAP1B and VCY2IP1/C19ORF5. RASSF1A association with MAP1B and VCY2IP1/C19ORF5 was subsequently confirmed in mammalian cell lines. This suggested that RASSF1A may exert its tumor-suppressive functions through interaction with the microtubules. We demonstrate that RASSF1A associates with the microtubules, causing them to exist as hyperstabilized circular bundles. We found that two naturally occurring tumor-associated missense substitutions in the RASSF1A coding region, C65R and R257Q, perturb the association of RASSF1A with the microtubules. The C65R and R257Q in addition to VCY2IP1/C19ORF5 showed reduced ability to induce microtubule acetylation and were unable to protect the microtubules against the depolymerizing action of nocodazole. In addition, wild-type RASSF1A but not the C65R or the R257Q is able to block DNA synthesis. Our data identify a role for RASSF1A in the regulation of microtubules and cell cycle dynamics that could be part of the mechanism(s) by which RASSF1A exerts its growth inhibition on cancer cells. 相似文献
1000.