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991.
992.
Cyclic vomiting syndrome (CVS) is a rare abnormality of the neuroendocrine system that affects 2% of children. It is a frequently missed diagnosis in the emergency department and may require a number of emergency department visits before the diagnosis is made. The objectives of this review are to identify the clinical features that suggest a diagnosis of CVS and to review the literature on its management. The MEDLINE and EMBASE databases were searched from January 1948 to October 2011 using the keywords 'Cyclic' or 'Vomiting'. Papers were excluded if they did not follow the consensus guidelines or if they were case reports. This review analysed 1093 cases of cyclic vomiting in 25 papers that fulfilled the inclusion criteria. All except one paper were retrospective studies. The size of these cohort studies ranged from three to 181 patients, with a mean patient size of 29. This review found that over 40% of patients have headaches/migraines, with associated anxiety and depression in ≈ 30% of cases. There is a family history of headaches/migraines in 38.9%, and this association was much stronger in the adult CVS cohort compared with the paediatric cohort. Compared with paediatric CVS, adults have a longer duration of attacks and they occur more frequently (5.9 vs. 3.4 days, 14.4 vs. 9.6 episodes/year). Limited data are available on the treatment of the acute phase of CVS, but in adults, sumatriptan has been shown to be effective. For prophylactic treatment, tricyclics are effective in both adult and paediatric CVS, with a clinical response in 75.5 and 67.6% of patients, respectively, in nonplacebo-controlled cohort studies. Furthermore, propranolol has been shown to be useful in children. CVS is an intractable illness with a major impact on the patient's quality of life. There is a long duration between the onset of symptoms and the diagnosis of the condition. There is a high association with headaches/migraines and anxiety/depression. The symptoms are more severe in adult-onset CVS. Tricyclic antidepressants have good efficacy in reducing the frequency/duration or the intensity of attacks. There is limited evidence on the acute management of CVS.  相似文献   
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994.
Worldwide Survey on Robotic AF Ablation . Introduction: The Hansen Robotic system has been utilized in ablation procedures for atrial fibrillation (AF). However, because of the lack of tactile feedback and the rigidity of the robotic sheath, this approach could result in higher risk of complications. This worldwide survey reports a multicenter experience on the methodology, efficacy, and safety of the Hansen system in AF ablations. Methods and Results: A questionnaire addressing questions on patient's demographics, procedural parameters, ablation success rate and safety information was sent to all centers where more than 50 robotic AF ablation cases have been performed. From June 2007 to December 2009, 1,728 procedures were performed at 12 centers utilizing the Hansen robotic navigation technology. The overall complication rate was 4.7% and the success rate was 67.1% after 18 ± 4 months of follow‐up. In 5 low volume centers there appeared to be a learning curve of about 50 cases (complication rate 11.2% for the first 50 cases vs 3.7% for the 51–100 cases; P = 0.044) and a trend showing a decrease of complication rate with increasing case volume. However, in the remaining 7 centers no learning curve was present and the complication rate was stable over time (3.7% for the first 50 cases vs 3.6% for the 51st case thereafter; P = 0.942). Conclusion: The Hansen robotic system can be used for AF ablation safely. In low volume centers, there appeared to be a learning curve of the first 50 cases after which the complication rate decreased. With a higher case volume, the success rate increased. (J Cardiovasc Electrophysiol, Vol. 23, pp. 820‐826, August 2012)  相似文献   
995.
Although exercise can significantly reduce the prevalence and severity of diabetic complications, no studies have evaluated the impact of exercise on nerve function in people with diagnosed diabetic peripheral neuropathy (DPN). The purpose of this pilot study was to examine feasibility and effectiveness of a supervised, moderately intense aerobic and resistance exercise program in people with DPN. We hypothesized that the exercise intervention can improve neuropathic symptoms, nerve function, and cutaneous innervation.MethodsA pre-test post-test design was used to assess change in outcome measures following participation in a 10-week aerobic and strengthening exercise program. Seventeen subjects with diagnosed DPN (8 males/9 females; age 58.4 ± 5.98; duration of diabetes 12.4 ± 12.2 years) completed the study. Outcome measures included pain measures (visual analog scale), Michigan Neuropathy Screening Instrument (MNSI) questionnaire of neuropathic symptoms, nerve function measures, and intraepidermal nerve fiber (IENF) density and branching in distal and proximal lower extremity skin biopsies.ResultsSignificant reductions in pain (? 18.1 ± 35.5 mm on a 100 mm scale, P = .05), neuropathic symptoms (? 1.24 ± 1.8 on MNSI, P = .01), and increased intraepidermal nerve fiber branching (+ 0.11 ± 0.15 branch nodes/fiber, P = .008) from a proximal skin biopsy were noted following the intervention.ConclusionsThis is the first study to describe improvements in neuropathic and cutaneous nerve fiber branching following supervised exercise in people with diabetic peripheral neuropathy. These findings are particularly promising given the short duration of the intervention, but need to be validated by comparison with a control group in future studies.  相似文献   
996.
BackgroundIt is unclear whether improvement in left ventricular (LV) ejection fraction (LVEF) following treatment with a combined α112-blockade can be attributed to improvement in LV contractility, to a reduction in afterload, and/or to improvements in LV remodeling and chamber size. We aimed to examine whether the observed improvement in LVEF following carvedilol treatment is due to changes in intrinsic myocardial contractility beyond changes in LV chamber size or loading conditions.Methods and ResultsIn 49 consecutive patients with chronic heart failure (HF), LVEF ≤35%, NYHA functional class II–IV, on angiotensin-converting enzyme inhibitors but not on ß-blockers, LV contractile performance and remodeling were assessed by comprehensive echocardiography at baseline and after 3 and 6 months of treatment with carvedilol. Carvedilol treatment resulted in significant improvements in LVEF, shortening fraction, and velocity of circumferential shortening (VCFc). There were no significant changes in the mean arterial blood pressure or systemic vascular resistance index; but LV end-systolic wall stress (LVESS), effective arterial elastance, ventriculoarterial coupling, and LV end-diastolic and end-systolic dimensions and volumes were significantly reduced. Estimated end-systolic elastance, VCFc-to-LVESS ratio, and pulsatile arterial compliance significantly improved after 6 months of treatment with carvedilol. The slope of the VCFc relationship to LVESS worsened from 0 to 3 months, but significantly improved from 3 to 6 months.ConclusionsDespite an initial transient negative inotropic effect from 0 to 3 months, carvedilol treatment was associated with a positive inotropic effect with significant improvement in load-independent indexes of myocardial contractility beyond what can be attributed to changes in LV chamber size and load after 3 months. There were no changes in systemic vascular resistance with carvedilol treatment; however, improvement in pulsatile arterial compliance and ventriculoarterial coupling suggested enhanced cardiac mechanoenergetic performance along with improved systemic arterial compliance.  相似文献   
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998.
999.
The Center for the AIDS Programme of Research in South Africa (CAPRISA) 004 and Pre-exposure Prophylaxis Initiative (iPrEx) studies demonstrated that topical or oral chemoprophylaxis could decrease HIV transmission. Yet to have an appreciable public health impact, physicians will need to be educated about these new HIV prevention modalities. Massachusetts physicians were recruited via e-mail to complete an online survey of their knowledge and use of HIV prevention interventions. Data were collected before (July-December, 2010) (n=178) and after (December, 2010-April, 2011) (n=115) the release of iPrEx data. Over the two time intervals, knowledge of oral PrEP significantly increased (79% to 92%, p<0.01), whereas knowledge about topical microbicides was already high (89% pre-iPrEx). Post-iPrEx, specialists were more knowledgeable about oral PrEP (p<0.01) and topical microbicides (p<0.001) than generalists. The majority of the respondents would prefer to prescribe topical microbicides (75%) than oral PrEP (25%; p<0.001), primarily because they perceived fewer side effects (95%). Respondents indicated that PrEP should be available if it were a highly effective, daily pill; however, ongoing concerns included: potential drug resistance (93%), decreased funds for other forms of HIV prevention (88%), medication side effects (83%), and limited data regarding PrEP's clinical efficacy (75%). Participants indicated that formal CDC guidelines would have the greatest impact on their willingness to prescribe PrEP (96%). Among Massachusetts physicians sampled, chemoprophylaxis knowledge was high, but current experience was limited. Although topical gel was preferred, responses suggest a willingness to adapt practices pending additional efficacy data and further guidance from normative bodies. Educational programs aimed at incorporating antiretroviral chemoprophylaxis into physicians' HIV prevention practices are warranted.  相似文献   
1000.
Vaginal microbicide gel trials for HIV prevention may require withdrawal of study product when a woman becomes pregnant. We assessed the potential impact of withdrawals in four trials by comparing self-reported sexual behavior pre- and post-pregnancy detection: (1) behavior in the month prior to positive pregnancy test versus behavior reported at the subsequent monthly visit; (2) behavior changes according to pregnancy status at the subsequent visit (continuing pregnancy versus not); (3) average sexual behaviors reported for all months prior to pregnancy detection versus all months after pregnancy was no longer detected; and (4) behavior changes among participants never testing positive for pregnancy. Pregnancy detection was associated with immediate reductions in self-reported numbers of partners and sex acts. The proportion of acts in which study gel was used following a negative pregnancy test did not return to pre-pregnancy levels. Pregnancies complicate the conduct and interpretation of vaginal microbicide trials when product must be withdrawn.  相似文献   
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