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111.
The aim of the present study was to measure clitoral artery blood flow throughout the menstrual cycle and in oral contraceptive users. We recruited healthy young women (n = 19, age range: 21-28 years; body-mass index: 18-23 kg/m2) without sexual dysfunction (Female Sexual Functioning Index criteria; Rosen et al., 2000). Clitoral arterial peak systolic velocity (PSV) in at least two phases of the same ovulatory cycle or during the second week of the pill was measured by doppler ultrasonography. Clitoral arterial PSV measures (cm/s) were superimposable during the follicular and the luteal phase of the menstrual cycle (10.4 +/- 1.2 versus 10.2 +/- 1.6), whereas a slight but significant increase (12.2 +/- 1.2, f = 3.99; p < 0.04) was evident at the time of ovulation. In addition, PSV measures were significantly higher in women taking hormonal contraception compared to women studied throughout the menstrual cycle (14.2 +/- 2.7 versus 10.8 +/- 1.5; p < .001). Whether or not these preliminary data may be of any significance to female sexual arousal throughout the menstrual cycle remains to be established.  相似文献   
112.
Conti R  Lisman J 《Hippocampus》2002,12(5):667-679
Synapses in the CA1 region of the hippocampus undergo bidirectional synaptic modification in response to different patterns of activity. Postsynaptic Ca2+ elevation can trigger either synaptic strengthening or weakening, depending on the properties of the local Ca2+ signal. During the pairing protocol for long-term potentiation (LTP) induction, the cell is depolarized under voltage-clamp and is given low-frequency synaptic stimulation. As an initial step toward understanding the Ca2+ dynamics during this process, we used confocal microscopy to study the Ca2+ signals in spines evoked by the depolarization itself. This depolarization activates voltage-dependent Ca2+ channels (VDCC), but whether these channels inactivate rapidly or remain functional throughout the long depolarizations used in the pairing protocol remains unknown. Cells were depolarized to 0 mV for 2-3 min. This depolarization led to a large initial elevation of Ca2+ in spines that never decayed back to resting levels. The maintained signal was close to the Kd of the low-affinity (5 microM) Ca2+ dye, Magnesium Green. We attempted to determine the functional role of this elevation, using the Ca2+-channel blocker D-890. The addition of D-890 in the internal solution produced a nearly complete abolition of the Ca2+ elevation during depolarization. Under these conditions, the NMDA conductance was normal, but LTP was almost completely blocked. This might suggest the importance of VDCC in LTP; however, we found that high concentrations of D-890 can directly inhibit calmodulin protein kinase II (CaMKII), an enzyme required for LTP induction. Thus, whereas D-890 is a useful tool for blocking postsynaptic VDCC, it cannot be used to study the contribution of these channels to plasticity. We conclude that the activation of VDCC produces a large and persistent elevation of Ca2+ in all spines, but does not produce either LTP or long-term depression (LTD) in the absence of synaptic stimulation. The possible reasons for this are discussed.  相似文献   
113.
Intrathecal chemotherapy in carcinomatous meningitis from breast cancer   总被引:4,自引:0,他引:4  
Meningeal metastases occur in 2-3% of patients with breast cancer, leading to neurological morbidity and increased mortality. The criteria for treatment choice are controversial and intrathecal chemotherapy (ITC) has no documented role in the management of this disorder. We therefore evaluated the efficacy of an ITC regimen for patients presenting with carcinomatous meningitis from breast cancer. PATIENTS AND METHODS: Patients with meningeal carcinomatosis with or without concomitant parenchymal brain metastasis, were treated with repeated courses of intrathecal chemotherapy according to the following alternated weekly schedule: Day 1: Thiotepa 10 mg, methotrexate 15 mg, hydrocortisone 30 mg; Day 5: cytarabine (Ara-C) 70 mg, methotrexate 15 mg, hydrocortisone 30 mg. Folinic acid 15 mg was given orally, every six hours after methotrexate on days 2-3 and 6-7. RESULTS: Thirteen consecutive patients were treated. The median age was 45 (range 30-67) years. Eleven patients had performance status (PS) 2-3. Nine patients had other metastatic sites; synchronous parenchymal brain metastasis were present in 5 patients. Concomitant systemic chemotherapy was administered in 5 patients and external whole brain radiotherapy in 7 patients. With 12 evaluable patients we observed no responses or improvement in symptoms. Side-effects were minimal. CONCLUSION: In our series of patients, ITC failed to provide objective response or relief in clinical symptoms. Despite evidence reported in the literature indicating symptomatic improvement after ITC in a number of patients with leptomeningeal metastasis, the results of our study confirm the controversial role of ITC. New drugs and new modalities of treatment should be studied in order to efficiently control meningeal involvement of breast cancer.  相似文献   
114.
Although effective plasma concentration ranges have been established for some antipsychotics, conventional and atypical, there is considerable inter-patient pharmacokinetic variation. Positron-emission tomography (PET) can be used to estimate D(2)-like receptor occupancy in the brain needed for an antipsychotic effect and the level above which extrapyramidal side effects (EPS) develop. For conventional antipsychotics, the window occupancy is approximately 70-80%. For the atypical antipsychotic risperidone, the antipsychotic effect starts at approximately 60% occupancy, with occupancy above 80% leading to EPS. The new formulation, risperidone long-acting injectable (RLAI), comprises risperidone in a biodegradable polymer. It is effective long-term at doses of 25 or 50 mg injected i.m. every 2 weeks. The constant and slow release of the long-acting formulation leads to less fluctuation in plasma levels and to a D(2)-like receptor occupancy which is below the threshold for EPS.  相似文献   
115.
Late onset childhood occipital epilepsy-Gastaut type (LOCOE) is a rare idiopathic epilepsy syndrome with an uncertain long-term prognosis. Elementary visual hallucinations and interictal spike-and-wave complexes in the occipital areas represent the main electroclinical findings of the syndrome. The functional nature of LOCOE has been emphasized together with the presence of genetic predisposition in the affected patients. Here, we report on two families in which two patients, respectively, showed electroclinical features compatible with LOCOE. Although further studies are needed to validate our observations, the involvement of two generations in one of the families we studied may corroborate the previously formulated hypothesis of an autosomal dominant model of inheritance in LOCOE. Of course, the identification of larger families is propaedeutic to linkage analysis studies.  相似文献   
116.
Alcoholic beverages are known to exert a protective effect on atherosclerotic disease. This study aimed to assess the in vivo and in vitro effects of alcohol on matrix metalloproteinase (MMP) -2 and -9, known to determine atherosclerosis progression. Eighteen healthy volunteers, regular drinkers (two standard alcohol servings/day, on average) at first examination (baseline) were asked to abstain from any alcoholic beverage for one week (abstention), and then to assume two standard alcohol servings of beer daily for 1 week (re-exposure). Activity of MMP-2 and -9, total antioxidant activity (AOA), glutathione (GSH) plasma levels were carried out at baseline, at the end of abstention, and after 1 week of re-exposure. To validate the in vivo results, MMP-2 activity and expression, AOA, and GSH, were determined in human smooth muscle cells treated for 96 h with increasing concentrations (12.5-100 mM) of ethanol. MMP-2, but not MMP-9 plasma activity was higher at abstention than at baseline or re-exposure (P<.001 and P< or =.005, respectively). Changes in AOA and GSH throughout the study were not significant. No correlation was found between MMPs and antioxidant activity. In vitro, ethanol at 25 mM reduced by around 10% MMP-2 activity (P=.003) in smooth muscle cells, whereas MMP-2 expression, AOA, and GSH were unaffected. Alcohol reduces MMP-2 plasma activity in healthy humans and in isolated vascular smooth muscle cells. This in vitro reduction is unrelated to MMP-2 expression in vascular cells or to antioxidant levels changes.  相似文献   
117.
Summary This study was carried out in order to investigate the effects of age on the urinary excretion of total and non-dialyzable hydroxyproline (OHPr) in normal subjects. We found that total urinary OHPr was negatively correlated with age but, by means of partial regression analysis, no correlation was found after correction for changes in creatinine clearance; on the contrary, non-dialyzable OHPr showed a statistically significant negative correlation with age (r=−0.56) even when creatinine clearance was held constant (p<0.05). A highly significant direct correlation was found between total and non-dialyzable OHPr in the whole group (r=0.54) and when only premenopausal women and men under 60 years of age were considered (r=0.51). No correlation was found when postmenopausal women and men more than 60 year-old were taken into account. Our data appear to indicate that also the decrease in osteogenetic activity is responsible for the physiological late involutional bone loss; they also show the importance of hormonal changes in inducing an uncoupling between bone formation and resorption. This work was supported by a grant from theConsiglia Nazionale delle Ricerche (CNR), Roma, Italy  相似文献   
118.
BACKGROUND: No data are available about the optimal duration of oral anticoagulant therapy (OAT) after an episode of venous thromboembolism (VTE) occurring in renal transplant (RT) recipients. Our study was undertaken to evaluate the risk of VTE recurrence in patients developing a first episode of VTE after RT. METHODS: Among 484 RT patients, 34 (7%) developed a first VTE: 28/34 VTE patients (Group 1) were prospectively studied, after stopping OAT. Group 1 was compared with a group of 84 patients without history of renal disease who had suffered from a first episode of VTE matched for age, sex and type of thrombotic event (Group 2) and with a matched group of 84 RT recipients with no history of VTE (Group 3). After OAT withdrawal, blood samples were obtained for thrombophilia and clotting activation markers (prothrombin fragment 1+2 (F1+2) and D-dimer plasma levels). RESULTS: During follow-up, 14/28 patients of Group 1 and 8/84 patients of Group 2 experienced VTE recurrence (P < 0.0005). Homocysteine, F1+2 and D-dimer plasma levels were significantly higher in Group 1 than in Group 2 and 3 (P < 0.0001 and <0.05 respectively) for all the three parameters. CONCLUSIONS: Our data outline the high risk of VTE recurrence in RT recipients. Strategies for VTE recurrence prevention are needed; Prolonged OAT, in spite of the high bleeding risk of RT patients, should be considered in this respect.  相似文献   
119.
120.
Controversial data are available on the association between the retrovirus-like long-terminal repeat (LTR) DQ-LTR13 and genetic susceptibility to type 1 diabetes and other autoimmune diseases. We analyzed DNA samples from 315 type 1 diabetic patients, 166 autoimmune Addison's disease (AAD) patients, 1,054 healthy subjects, and 144 families of type 1 diabetic offspring. DQ-LTR13 was more frequent among patients than healthy subjects (P(c) < 0.0006), and a preferential transmission of DQB1*0302-LTR13(+) from parents to type 1 diabetic offspring was observed. DQ-LTR13 was in linkage disequilibrium (LD) with DQB1*0302 but not DQB1*0201. The presence of DQ-LTR13 increased the odds ratio of DQB1*0302 2.9- to 3.2-fold for type 1 diabetes and AAD. DRB1*0403 was absent in all of the 169 DRB1*04-positive patients but present in 27% (34 of 127) DRB1*04-positive healthy subjects (P(c) < 0.001). DQ-LTR13 was detected in 1 of 34 (3%) DRB1*0403-positive healthy subjects and 36 of 93 (39%) individuals carrying another DRB1*04 allele (P(c) = 0.002). Multivariate logistic regression analysis revealed that DQ-LTR13 is not independently associated with type 1 diabetes and AAD after correction for DQB1*0302 and DRB1*0403. Conversely, DQB1*0201, DQB1*0302, DRB1*0401, and DRB1*0403 were all significantly associated with disease risk also after correction for DQ-LTR13. We provide conclusive evidence that the genetic association of DQ-LTR13 with type 1 diabetes and AAD is primarily due to a LD with DQB1*0302 and DRB1*0403.  相似文献   
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