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991.
EO-122, a newly developed structural analog of lidocaine, has recently been shown to suppress ventricular arrhythmias in a few clinical studies in patients and in experimental animals. In the present study, we investigated the effects of EO-122 on the electrophysiological properties of guinea pig papillary muscle and ventricular myocytes by means of standard microelectrode and whole-cell recording techniques, respectively, At the concentration range of 10(-7)-10(-4) M (cycle length, 2000 ms), resting potential and action potential duration (APD90) were not altered by the drug. Action potential amplitude and APD50 were reduced (p less than 0.01) by 10(-4) M, and Vmax was reduced (p less than 0.01) by EO-122 greater than or equal to 10(-5) M. The effect of EO-122 on Vmax was use-dependent. At 10(-6) and 10(-5) M (cycle length, 2000 ms), the time constant for onset of block (tau on) was 37.0 +/- 13.2 and 26.0 +/- 3.4 s, respectively. The recovery kinetics from use-dependent block was not monoexponential, and the estimated "time constant" for recovery was 76.5 s. We examined the effects of EO-122, 10(-5) M, on the membrane currents in ventricular myocytes and found that the drug attenuated the slow inward current (Isi). EO-122 reduced peak Isi by 68.6 +/- 5.2% (p less than 0.005), whereas the outward current was unchanged. The present study demonstrates that EO-122 blocks both the fast inward (Na+) and the slow inward (Ca2+) channels, and these effects are probably responsible for the antiarrhythmic effects of the drug.  相似文献   
992.
Eleven cases of supratentorial neuroepithelial tumor presenting in infancy are reported. The tumors were characterized by their voluminous size, their intense desmoplasia, and the frequent presence of divergent astrocytic and ganglionic differentiation as demonstrated by special neurohistological and immunohisto- and immunocytochemical techniques. All the tumors presented in subjects below the age of 18 months, usually within the first 4 months of life. They most often involved the frontal and parietal regions and were composed predominantly of a dense desmoplastic tissue superficially resembling a moderately cellular fibroma. The fibroblastic elements were admixed with variable numbers of pleomorphic neuroepithelial cells. Divergent astrocytic and neuronal differentiation was demonstrable in nine of the 11 tumors. All showed astrocytic differentiation. The study of one example by electron microscopy, immunocytochemistry, and tissue culture disclosed that the astrocytic tumor cells were partly invested by a pericytoplasmic basal lamina. Successful total or near-total surgical resection has been followed by a favorable postoperative course extending in some cases over many years of tumor-free survival. The name "desmoplastic infantile ganglioglioma" is proposed for this apparently distinct clinicopathological entity, whose massive size is indicative of a pre- or perinatal origin. Its identification can be achieved by careful histological analysis and is of obvious prognostic significance.  相似文献   
993.

Purpose

To evaluate the cost-effectiveness of manual therapy according to the Utrecht School (MTU) in comparison with physiotherapy (PT) in sub-acute and chronic non-specific neck pain patients from a societal perspective.

Methods

An economic evaluation was conducted alongside a 52-week randomized controlled trial, in which 90 patients were randomized to the MTU group and 91 to the PT group. Clinical outcomes included perceived recovery (yes/no), functional status (continuous and yes/no), and quality-adjusted life-years (QALYs). Costs were measured from a societal perspective using self-reported questionnaires. Missing data were imputed using multiple imputation. To estimate statistical uncertainty, bootstrapping techniques were used.

Results

After 52 weeks, there were no significant between-group differences in clinical outcomes. During follow-up, intervention costs (β:€?32; 95 %CI: ?54 to ?10) and healthcare costs (β:€?126; 95 %CI: ?235 to ?32) were significantly lower in the MTU group than in the PT group, whereas unpaid productivity costs were significantly higher (β:€186; 95 %CI:19–557). Societal costs did not significantly differ between groups (β:€?96; 95 %CI:?1975–2022). For QALYs and functional status (yes/no), the maximum probability of MTU being cost-effective in comparison with PT was low (≤0.54). For perceived recovery (yes/no) and functional status (continuous), a large amount of money must be paid per additional unit of effect to reach a reasonable probability of cost-effectiveness.

Conclusions

From a societal perspective, MTU was not cost-effective in comparison with PT in patients with sub-acute and chronic non-specific neck pain for perceived recovery, functional status, and QALYs. As no clear total societal cost and effect differences were found between MTU and PT, the decision about what intervention to administer, reimburse, and/or implement can be based on the preferences of the patient and the decision-maker at hand.

Trial registration

ClinicalTrials.gov Identifier: NCT00713843
  相似文献   
994.
995.
A girl born with congenital paresis of cranial nerves III, IV, and VII (Moeblus syndrome) subsequently developed a progressive peripheral neuropathy. There was suggestive evidence of a familial neuropathy with autosomal dominant inheritance in three family members. The patient also had hypogonadotrophic hypogonadism and anosmia (Kallmann syndrome).  相似文献   
996.
Patients who sustain a fracture are at greatest risk of recurrent fracture during the next 2 years. We propose three models to identify subjects most at risk of an imminent fracture, according to fracture site (any fracture, major osteoporotic fracture [MOF] or central). They were constructed using data of the prospective Frisbee cohort, which includes 3560 postmenopausal women aged 60 to 85 years who were followed for at least 5 years. A total of 881 subjects had a first incident validated fragility fracture before December 2018. Among these, we validated 130 imminent fractures occurring within the next 2 years; 79 were MOFs, and 88 were central fractures. Clinical risk factors were re-evaluated at the time of the index fracture. Fine and Gray proportional hazard models were derived separately for each group of fractures. The following risk factors were significantly associated with the risk of any imminent fracture: total hip bone mineral density (BMD) (p < 0.001), a fall history (p < 0.001), and comorbidities (p = 0.03). Age (p = 0.05 and p = 0.03, respectively) and a central fracture as the index fracture (p = 0.04 and p = 0.005, respectively) were additional predictors of MOFs and central fractures. The three prediction models are presented as nomograms. The calibration curves and the Brier scores based on bootstrap resampling showed calibration scores of 0.089 for MOF, 0.094 for central fractures, and 0.132 for any fractures. The predictive accuracy of the models expressed as area under the receiver operating characteristic (AUROC) curve (AUC) were 0.74 for central fractures, 0.72 for MOFs, and 0.66 for all fractures, respectively. These AUCs compare well with those of FRAX and Garvan to predict the 5- or 10-year fracture probability. In summary, five predictors (BMD, age, comorbidities, falls, and central fracture as the incident fracture) allow the calculation with a reasonable accuracy of the imminent risk of fracture at different sites (MOF, central fracture, and any fracture) after a recent sentinel fracture. © 2021 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).  相似文献   
997.
Buprenorphine, a semisynthetic thebaine derivative, is a unique opioid, as it has activity at multiple receptors, including mu (partial agonist), kappa (antagonist), OLR-1 (agonist), and delta (antagonist). Because buprenorphine's pharmacology is relatively complex, misconceptions about its actions are common. Most other opioids act solely or predominately as full mu receptor agonists. Common practice at many institutions calls for the cessation of regular buprenorphine use 48–72 hours prior to surgery. This practice is based on three foundational theories that have come from scant data about the properties of buprenorphine: (1) that buprenorphine is only a partial mu agonist and therefore is not a potent analgesic; (2) because buprenorphine has a ceiling effect on respiratory depression, it also has a ceiling effect on analgesia; and (3) that buprenorphine acts as a “blockade” to the analgesic effects of other opiates when coadministered due to its strong binding affinity. However, several recent studies have called this practice into question. At our institution, we continue buprenorphine perioperatively, whenever possible, in order to provide superior pain control, discourage potentially problematic use and the more dangerous side effects of full mu agonist opiates, and avoid putting recovery at risk for those with opiate dependency issues. We present a unique case comparing two different outcomes for the same surgical course performed at two different times on the same chronic pain patient. These differences may be attributable to the variable of buprenorphine being present for one perioperative course and not the other. Pain control was easier to achieve, and functional recovery was greater when buprenorphine was maintained throughout the perioperative period when compared with using a full mu agonist opioid for chronic pain preoperatively. This is an outcome that much of the literature heretofore suggests would be unlikely. We review some aspects of buprenorphine's unique pharmacology that may explain why remaining on buprenorphine perioperatively may be preferable, which contradicts many practice guidelines.  相似文献   
998.
重症病人的贫血和红细胞输注   总被引:1,自引:0,他引:1  
简介 重症病人的定义并不是很明确,但大多数临床医生指的重症病人是那些伴有器官衰竭的急性病人。在英国,伴有多器官衰竭的病人在ICU(重症监护室)医治。贫血是重症病人的常见并发症。在ICU内,对贫血的治疗是输注异体红细胞。除禁止输血治疗的病人外,进入ICU的患者大概有40%接受过红细胞输注。输血实际操作过程中存在的多种不确定因素,直接关系到输血的安全性、有效性及输血指征。本文集中讨论以下三方面的问题:  相似文献   
999.
Single-case design with the randomization test (RT) has been proposed as an alternative to the binomial distribution (BD) tables of Thornton and Raffin (1978) to assess changes in speech recognition performance in individual subjects. The present study investigated whether data analyzed using both approaches would result in similar outcomes. Sixty-two adults with normal hearing were evaluated using phoneme scoring and a restricted alternating treatments design under two signal-to-noise conditions. Results revealed a significant correlation between the RT and a BD analysis using at least 50-word lists, although the BD analysis was a more sensitive measure. The absence of correlation between the RT with a BD analysis using 25-word lists challenges the common clinical practice of using reduced list size, and supports the use of phoneme scoring and other attempts to find clinically acceptable yet evidence-based solutions to overcome the conflict between time and accuracy.  相似文献   
1000.
We evaluated the production of antibodies against insulin in a genetically well-defined population. In the first study, 124 young patients with type I diabetes for longer than 6 mo were included. Anti-insulin antibodies were detected by polyethyleneglycol (PEG) precipitation after incubation of acidified, charcoal-stripped sera with 125I-labeled pork insulin and were expressed as microunits insulin bound per milliliter whole serum. For comparison, the patients were divided into six groups based on HLA DR antigens: 3/3, 3/-, 4/4, 4/-, 3/4, and -/-(-is non-DR3 or -DR4). The mean age of the patients was 14.7 +/- 0.5 yr; the duration of diabetes was 5.8 +/- 0.4 yr; and the glucose control, as measured by hemoglobin A1c was average (7.6 +/- 0.2%). There were no significant differences in any of these parameters among the patients in any of the HLA DR groups. Patients expressing DR3/3 had significantly lower insulin binding than the rest of the groups (2.5 +/- 0.4 vs. 13.6 +/- 1.4 microU/ml, P less than 0.0001). Patients with DR3/ - did not differ in insulin-binding capacity from the other groups. The type of insulin used for replacement was not correlated with the serum insulin-binding capacity. In a second study, sera from 48 children, newly diagnosed with type I diabetes, were examined for the presence of insulin binding before treatment with exogenous insulin and compared with sera from 80 children without diabetes or a family history of diabetes and from 103 unaffected HLA-identical or haploidentical siblings of a child with type I diabetes.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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