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71.
Hemostatic alterations in patients with benign and malignant colorectal disease during major abdominal surgery. 总被引:2,自引:0,他引:2
We determined sensitive markers of coagulation and fibrinolysis in plasma of 20 patients with malignant colorectal disease as compared to 17 patients with benign colorectal disease. Thrombin/antithrombin III complex (TAT), soluble fibrin (SF), total fibrinogen and fibrin degradation products (TDP), plasminogen activator inhibitor type-1 (PAI-1), urokinase-type plasminogen activator (uPA) and uPA receptor (uPAR) were measured preoperatively, starting anesthesia, during surgery and postoperatively. The purpose was to verify the supposed hypercoagulable state of cancer patients. In addition, we investigated whether the hemostatic alterations induced by general anesthesia and major abdominal surgery differed between the two groups. Patients with colorectal cancer showed initially an altered balance of hemostasis with a preponderance of procoagulant activity and fibrinolytic inhibition, as noted by marginally elevated TAT and PAI-1 plasma levels. The stimulus of anesthesia induction alone was sufficient to trigger not only activation of coagulation in these patients but also further activation of fibrinolysis and increased fibrinolytic inhibition. The marked activation of coagulation and fibrinolysis and enhanced fibrinolytic inhibition during surgery was more pronounced in patients with malignancy as compared to the control group. Postoperatively, a shift of the normal balance of hemostasis with a slight preponderance of fibrinolytic inhibition was observed, as evidenced by a marginally elevated PAI-1 plasma levels. The results of this study strengthen the hypothesis of a hypercoagulable state in patients with colorectal malignancy that may favor the development of thrombosis in this patient group. 相似文献
72.
Release of somatostatin from extra-hypothalamic rat brain slices: inhibition by dopamine and morphine 总被引:3,自引:0,他引:3
Calcium-dependent potassium-evoked release of somatostatin-like immuno-reactivity (SSLI) and preloaded [3H]noradrenaline ([3H]NA) could be demonstrated simultaneously from slices of rat cerebral cortex, globus pallidus and trigeminal nucleus. The release of [3H]NA from cortical slices differed from that of somatostatin (SS) in its K+-dependency, with the release of SS having a higher threshold. Both morphine (10 microM) and dopamine (50 microM) significantly inhibited the potassium-evoked release of SS from the cerebral cortex, without affecting its basal release. The effect of morphine was naloxone reversible. 相似文献
73.
To evaluate the accuracy of small volume estimation, both in vivo and in vitro, measurements with a three-dimensional (3D) ultrasound (US) system were carried out. A position sensor was used and the transmitting frequency was 10 MHz. Balloons with known volumes were scanned while rat kidneys were scanned in vivo and in vitro. The Archimedes' principle was used to estimate the true volume. For balloons, the 3D US system gave very good agreement with true volumes in the volume range 0.1 to 10.0 mL (r = 0.999, n = 45, mean difference +/- 2SD = 0.245 +/- 0.370 mL). For rat kidneys in vivo (volume range 0.6 to 2.7 mL) the method was less accurate (r = 0.800, n = 10, mean difference +/- 2SD = -0.288 +/- 0.676 mL). For rat kidneys in vitro (volume range 0.3 to 2.7 mL) the results showed good agreement (r = 0.981, n = 23, mean difference +/- 2SD = 0.039 +/- 0.254 mL). For balloons, kidneys in vivo and in vitro, the mean percentage error was 9.3 +/- 4.8%, -17.1 +/- 17.4%, and 4.6 +/- 11.5%, respectively. This method can estimate the volume of small phantoms and rat kidneys and opens new possibilities for volume measurements of small objects and the study of organ function in small animals. (E-mail ). 相似文献
74.
Summary The release of pancreatic polypeptide (PP) by gut hormones, acetyl choline and adrenaline was investigated in an isolated perfused pancreas preparation. PP was potently released by 1 nmol/l caerulein (186±12%, p<0.001) and gastric inhibitory peptide (GIP) (211±31%, p<0.005) as well as by 1 [mol/l acetyl choline (1097±59%, p<0.001). A significant two-fold release of PP was also evoked by 1 nmol/l vasoactive intestinal peptide (VIP) (129±38%, p<0.02 and gastrin (108±25% p<0.01). Insulin release, induced by high glucose concentration was enhanced by both GIP (210 ±38%, p<(0.01) and VIP (48±5%, p<0.001). In addition GIP enhanced the release of glucagon by 179±18% (p<0.001) at 1.4 mmol/l glucose and by 127±24% (p<0.005) at 8.3 mmol/l glucose. Thus no simple inter-relationship appears to exist between the control of the three circulating islet hormones. 相似文献
75.
Nils Milman Claus B. Andersen Bo Baslund Annika Loft Martin Iversen 《The clinical respiratory journal》2007,1(2):106-113
Background: Sarcoid granuloma formation involves the orchestration of cytokines and chemokines, which modulate the host's immune response to the antigen stimulus. The release of cytokines enhances expression of the pro‐inflammatory cytokine tumour necrosis factor‐α (TNF), which plays a crucial role in the formation of sarcoid granuloma, being released from T‐lymphocytes and alveolar macrophages. Objective: The aim of this study was to evaluate the effect of infliximab in a case of pulmonary sarcoidosis using a histological approach. Materials and Methods: A 44‐year‐old man with biopsy verified chronic pulmonary sarcoidosis being resistant to treatment with corticosteroids and cell cycle inhibitors. Persisting disease activity was confirmed by declining lung function tests and a positive fluorine‐18‐fluorodeoxyglucose–positron emission tomography scan. The patient was treated with a single course of infliximab 3‐mg/kg body weight; 11 days later, a single lung transplantation was performed. Immunohistological staining with the macrophage marker CD68 was performed on lung tissue and mediastinal lymph node tissue from both the initial diagnostic evaluation (prior to infliximab) as well as from the explanted lung (after infliximab). Results: Biopsy specimens from lung and mediastinal lymph nodes prior to infliximab demonstrated sarcoid granulomas, and staining with CD68 showed dense infiltration by macrophages (epithelioid cells) in the central part of the granulomas. In contrast, biopsies from the explanted lung after infliximab demonstrated acellular sarcoid granulomas with central amorphous masses, and staining with CD68 showed complete absence of macrophages. Conclusions: In this patient, the TNF inhibitor infliximab appeared to induce resolution of sarcoid granulomas starting with disappearance of macrophages probably caused by cell lysis or apoptosis. Please cite this paper as: Milman N, Andersen CB, Baslund B, Loft A and Iversen M. Does tumour necrosis factor‐α inhibitor infliximab induce histological resolution of pulmonary sarcoid granulomas? The Clinical Respiratory Journal 2007; 1:106–113. 相似文献
76.
M.M. Adams H.S. Donohue M.C. Linville E.A. Iversen I.G. Newton J.K. Brunso-Bechtold 《Neuroscience》2010
Caloric restriction (CR) is a reduction of total caloric intake without a decrease in micronutrients or a disproportionate reduction of any one dietary component. While CR attenuates age-related cognitive deficits in tasks of hippocampal-dependent memory, the cellular mechanisms by which CR improves this cognitive decline are poorly understood. Previously, we have reported age-related decreases in key synaptic proteins in the CA3 region of the hippocampus that are stabilized by lifelong CR. In the present study, we examined possible age-related changes in the functional microcircuitry of the synapses in the stratum lacunosum-moleculare (SL-M) of the CA3 region of the hippocampus, and whether lifelong CR might prevent these age-related alterations. We used serial electron microscopy to reconstruct and classify SL-M synapses and their postsynaptic spines. We analyzed synapse number and size as well as spine surface area and volume in young (10 months) and old (29 months) ad libitum fed rats and in old rats that were calorically restricted from 4 months of age. We limited our analysis to SL-M because previous work demonstrated age-related decreases in synaptophysin confined to this specific layer and region of the hippocampus. The results revealed an age-related decrease in macular axo-spinous synapses that was not reversed by CR that occurred in the absence of changes in the size of synapses or spines. Thus, the benefits of CR for CA3 function and synaptic plasticity may involve other biological effects including the stabilization of synaptic proteins levels in the face of age-related synapse loss. 相似文献
77.
Humphries SE Cranston T Allen M Middleton-Price H Fernandez MC Senior V Hawe E Iversen A Wray R Crook MA Wierzbicki AS 《Journal of molecular medicine (Berlin, Germany)》2006,84(3):203-214
As part of a randomised trial [Genetic Risk Assessment for Familial Hypercholesterolaemia (FH) Trial] of the psychological
consequences of DNA-based and non-DNA-based diagnosis of FH, 338 probands with a clinical diagnosis of FH (46% with tendon
xanthomas) were recruited. In the DNA-based testing arm (245 probands), using single-strand conformation polymorphism of all
exons of the low-density lipoprotein receptor (LDLR) gene, 48 different pathogenic mutations were found in 62 probands (25%), while 7 (2.9%) of the patients had the R3500Q mutation
in the apolipoprotein B (APOB) gene. Compared to those with no detected mutation, mean untreated cholesterol levels in those with the APOB mutation were similar, while in those with an LDLR mutation levels were significantly higher (None=9.15±1.62 vs LDLR=9.13±1.16 vs APOB=10.26±2.07 mmol/l p<0.001, respectively). Thirty seven percent of the detected mutations were in exon 3/4 of LDLR, and this group had significantly higher untreated cholesterol than those with other LDLR mutations (11.71±2.39 mmol/l vs 9.88±2.44 mmol/l, p=0.03), and more evidence of coronary disease compared to those with other LDLR or APOB mutations (36 vs 13% p=0.04). Of the probands with a detected mutation, 54 first-degree relatives were identified, of whom 27 (50%) had a mutation.
Of these, 18 had untreated cholesterol above the 95th percentile for their age and gender, but there was overlap with levels
in the non-carrier relatives such that 12% of subjects would have been incorrectly diagnosed on lipid levels alone. In the
non-DNA-based testing arm (82 probands) only 19 of the 74 relatives identified had untreated cholesterol above the 95th percentile
for their age and gender, which was significantly lower (p<0.0005) than the 50% expected for monogenic inheritance. These data confirm the genetic heterogeneity of LDLR mutations in the UK and the deleterious effect of mutations in exon 3 or 4 of LDLR on receptor function, lipids and severity of coronary heart disease. In patients with a clinical diagnosis of FH but no detectable
mutation, there is weaker evidence for a monogenic cause compared with relatives of probands with LDLR mutations. This supports the usefulness of DNA testing to confirm diagnosis of FH for the treatment of hyperlipidaemia and
for further cascade screening. 相似文献
78.
The influence of inhaled steroids and predictive factors on the response to bronchial allergen challenge (BCA) was evaluated in. 80 asthmatics allergic to Dermatophagoides pteronyssinus (Der p). All underwent BCA with Der p and measurement of early (EAR) and late asthmatic reaction (LAR). The cumulative dose of allergen producing 20% fall in FEV1 , in the EAR (PD20 ) was calculated. Bronchial histamine provocation, conjunctival provocation test (CPT), and skin prick test with Der p extract were performed. Specific IgE to Der p in serum (RAST), blood eosinophil (EOS) count, serum eosinophil cationic protein, and eosinophil protein X were measured. Thirty patients (38%) were treated with inhaled steroids. All patients had at least a 20% fall in FEV1 in EAR. Some 42% of nonsteroid- and 33% of steroid-treated patients had LAR with fall in peak flow of at least 20%. For patients not treated with steroid, 35% of variation in PD20 was explained by RAST and histamine reactivity, and 53% of variation of observed PD20 could be predicted. The baseline FEV1 , EOS, and EAR explained 28% of variation in LAR, and 28% of variation in observed LAR could be predicted. For patients treated with steroids, 38% of variation in PD20 was explained by EOS and histamine reactivity, and only 18% of variation of observed PD20 could be predicted. For patients treated with steroids, it was impossible to predict LAR. We conclude that to achieve a quantitative estimation of allergen-specific EAR and LAR, BCA cannot be replaced by the tests used in this study. Treatment with inhaled steroids modifies the response to BCA, making quantitative prediction of EAR less accurate and prediction of the magnitude of LAR impossible. 相似文献
79.
Human papillomavirus type 16 in vulvar carcinoma, vulvar intraepithelial neoplasia, and associated cervical neoplasia. 总被引:1,自引:0,他引:1
U H?rding S Daugaard A K Iversen J Knudsen J E Bock B Norrild 《Gynecologic oncology》1991,42(1):22-26
Vulvar intraepithelial neoplasia (VIN) is becoming more widespread and the patients are becoming still younger. Although progression to invasive vulvar carcinoma is uncommon, local recurrences are frequent and about one-quarter of the patients have multicentric genital disease. The aim of the present study was to search for a possible significant association of human papillomavirus (HPV) infection with vulvar carcinoma, recurrences, and multicentric disease. We used the polymerase chain reaction to examine vulvar and cervical biopsies from 43 patients with vulvar neoplasia for HPV type 16, which is the subtype most often detected in genital malignant or premalignant lesions. HPV 16 DNA sequences were found in 14 of 24 (58%) vulvar squamous carcinomas and in 15 of 19 (79%) VIN lesions. Nine patients (21%) had associated cervical neoplasia and six of these harbored HPV 16 in both lesions. Patients with recurrent intraepithelial neoplasia had a significantly higher incidence of HPV 16-positive lesions. No association was found with regard to the occurrence of multicentric disease or risk of malignant progression. 相似文献
80.
Eliel Bayever Kathleen M. Haines Patrick L. Iversen Raymond W. Ruddon Samuel J. Pirruccello Charles P. Mountjoy Mark A. Arneson Larry J. Smith 《Leukemia & lymphoma》1994,12(3):223-231
Cells were treated in vitro with oligodeoxyribonucleotide phosphorothioates (ODNs) complementary to sites common to both wild-type and mutant p53 nucleotide sequences. Acute myelogenous leukemia (AML) blasts from peripheral blood were exposed to four different p53 ODNs and showed anti-leukemic effects in suspension culture. This effect continued after removal of the ODN from the medium. Blocking of self-renewal of the leukemic blast stem cells in secondary plating of cells from cloning assays by two of the p53 ODNs was also observed. Control ODNs had no effect on leukemic blasts. Treatment of normal bone marrow cells with the four p53 ODNs did not influence their growth, nor was there any effect by the p53 ODNs on the leukemic cell-line, HL60, that does not express p53. These data suggest that p53 ODNs are selectively toxic to primary myelogenous blasts and may be therapeutically useful in AML. 相似文献