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51.
Tuberous sclerosis is an autosomal dominant disease with variable expression. Little is known about the intrauterine course of the disease and the fetal age at which specific abnormalities may be detected. The role of prenatal detection of cardiac tumours in the diagnosis of two fetuses at 28 and 32 weeks' gestation based on fetal echocardiography is discussed. The prenatal and postnatal course of the disease is described.  相似文献   
52.
Carbamate derivatives of N-propargylaminoindans (Series I) and N-propargylphenethylamines (Series II) were synthesized via multistep procedures from the corresponding hydroxy precursors. The respective rasagiline- and selegiline-related series were designed to combine inhibitory activities of both acetylcholine esterase (AChE) and monoamine oxidase (MAO) by virtue of their carbamoyl and propargylamine pharmacophores. Each compound was tested for these activities in vitro in order to find molecules with similar potencies against each enzyme. Compounds with such dual AChE and MAO inhibitory activities are expected to have potential for the treatment of Alzheimer's disease. The observed SAR also offers insight into the requirements of the active sites on these enzymes. A carbamate moiety was found to be essential for AChE inhibition, which was absent in the corresponding hydroxy precursors. The propargyl group caused 2-70-fold decrease in AChE inhibitory activity (depending on the position of the carbamoyl group) of Series I, but had little or no effect in Series II. Thus, the 6- and 7-carbamyloxyphenyls in Series I were either equipotent to, or slightly (2- to 5-fold) less active as AChE inhibitors than, the corresponding compounds in Series II, while the 4-carbamyloxyphenyls were more potent. The presence of the carbamate moiety in 6- and 7-carbamyloxyphenyls of Series I, considerably decreased MAO-A and -B inhibitory activity, compared to that of the parent hydroxy analogues, while the opposite was true for Series II. Thus, the 6- and 7-carbamyloxyphenyls in Series I were 2-3 orders of magnitude weaker MAO inhibitors while the 4- carbamyloxyphenyls were equipotent with the corresponding compounds in Series II. In both series, N-methylation of the propargylamine enhanced the MAO (A and B equally) inhibitory activities and decreased the AChE inhibitory activity. Two candidates belonging to the indan and tetralin ring systems (24c, 27b) and one phenethylamine (53d) were identified as possible leads for further development based on the following criteria: (a) comparable AChE and MAO-B inhibitory activities, (b) good to moderate AChE inhibitory activity, and (c) lack of strong MAO-A selectivity. However, it is likely that these compounds will be metabolized to the corresponding phenols, with inhibitory activities against AChE and/or MAO-A or -B, different from those of the parent carbamates. Thus, the apparent enzyme inhibition will be a result of the combined inhibition of all of these individual metabolites. The results of our ongoing in vivo screening programs will be published elsewhere.  相似文献   
53.
The discovery of the selective AMPA antagonist character of 2,3-benzodiazepine derivative GYKI 52466 (5) in the late eighties and the recognition of the non-competitive nature of its mode of action some years later set off the world-wide search for novel class of drugs. Notably the quest to develop new antiepileptic and neuroprotective medicines, which allosterically inhibit the AMPA sensitive glutamate operated channels. This review summarises our present knowledge about the allosteric site, dubbed "GYKI site" where the 2,3-benzodiazepines are supposed to bind to. The structure-activity relationships among AMPA antagonist 2,3-benzodiazepines and their structural analogues with similar biological profile are reviewed in a possibly comprehensive fashion. The chemical synthesis of 2,3-benzodiazepines is shortly described. The in vitro and in vivo experimental methods used for pharmacological characterisation of the biologically active compounds are briefly explained. Finally the therapeutic potential of 2,3-benzodiazepines i.e. the main fields of their clinical utility are outlined with special regard to talampanel (20) in the light of the ongoing clinical trials with this new drug candidate.  相似文献   
54.
BACKGROUND: Systemic inflammatory response syndrome (SIRS) and sepsis of unknown origin are common complications of critically ill patients in the ICU. These patients frequently have unreliable clinical exams and are candidates for exploratory laparotomy. Although abdominal CT is commonly used because it is less invasive than laparotomy, it is often unreliable or unobtainable. Bedside laparoscopy is an alternative technique that may be more accurate than CT in selected patients and less invasive than laparotomy. METHODS: We performed diagnostic laparoscopy (DL) in a series of ICU patients with SIRS/septic state of unknown origin between May 1997 and June 1998. All patients were unstable and required significant respiratory and hemodynamic support. Laparoscopy was either performed in the ICU at the patient's bedside or in the operating room. CT scan of the abdomen had been performed on most of the patients who were stable enough to transport. Confirmation of diagnosis was obtained either by laparotomy, autopsy, or clinical recovery. RESULTS: Among the 17 eligible patients, 16 underwent successful DL. Insufflation was impossible in one patient because of high intraabdominal pressure. Bedside evaluations were performed in 14 of the 17 patients. There were no complications from the laparoscopy. Six patients were identified as positive (four intestinal ischemia, two cholecystitis); the other 10 had negative explorations. Follow-up on two patients with negative laparoscopy was incomplete due to denied postmortem. Laparoscopic diagnoses were confirmed in the remaining 14 patients by laparotomy (six cases), postmortem (three cases), or recovery (five cases), with an accuracy of 100%. The overall accuracy of abdominal CT obtained in nine of the 14 patients was 33%. CONCLUSIONS: DL in a select group of critical ICU patients is safe and accurate, whereas CT scan tends to be inaccurate and is often unobtainable due to patient instability. Performing the procedure at the bedside can expedite the diagnosis, eliminate the burden for transfer, and save on anesthesia and operating room charges.  相似文献   
55.
Summary The objective of this study was to assess the efficacy of corticosteroids in hastening the recovery of children with postpericardiotomy syndrome, using a randomized double-blind placebo-controlled trial in a tertiary care referral center for pediatric cardiology and cardiac surgery. Twenty-one children, 6 months of age or older (mean age 3.9 years) with postpericardiotomy syndrome following open or closed heart surgery were administered either prednisone 2 mg/kg/day reducing to zero over 14 days (n=12) or placebo (n=9). Progress was monitored by daily clinical assessment and alternate day cross-sectional echocardiograms. The primary measures of efficacy were the number of patients in remission at 72 h and at 1 week. No difference in remission rates were found at 72 h, but at 1 week significantly more children treated with prednisone were in remission (placebo 3/9; prednisone 10/12,p=0.03). A trend to faster resolution of all symptoms and signs was seen in the prednisone-treated group but this was not associated with earlier hospital discharge. Enlargement of pericardial effusion was seen in two children treated with steroids. No complications of treatment were encountered. Prednisone hastens the recovery of children with postopericardiotomy syndrome. Pericardial effusions may increase in size despite the use of corticosteroids.Presented in part at the Society for Pediatric Research, New Orleans, May 1991.  相似文献   
56.
Depsipeptide, FR901228, a novel cyclic peptide inhibitor of histone deacetylase with a unique cytotoxicity profile is currently in phase I clinical trials. Here we demonstrate that, in addition to G2/M arrest, FR901228 causes G1 arrest with Rb hypophosphorylation. In vitro kinase assays demonstrated no direct inhibition of CDK activity, however, an inhibition was observed in CDKs extracted from cells exposed to FR901228. Cyclin D1 protein disappeared between 6 and 12 hours after treatment with FR901228, whereas cyclin E was upregulated. While it did not induce wt p53, FR901228 did induce p21(WAF1/CIP1)in a p53-independent manner. Cell clones lacking p21 were not arrested in G1 phase, but continued DNA synthesis and were arrested in G2/M phase following FR901228 treatment. Finally, FR901228 blunted ERK-2/MAPK activation by EGF whereas early signal transduction events remained intact since overall cellular tyrosine phosphorylation after EGF stimulation was unaffected. Thus, FR901228, while not directly inhibiting kinase activity, causes cyclin D1 downregulation and a p53-independent p21 induction, leading to inhibition of CDK and dephosphorylation of Rb resulting in growth arrest in the early G1 phase. In contrast to the G1 arrest, the G2/M arrest is p21-independent, but is associated with significant cytotoxicity.  相似文献   
57.
Objective: In contrast with combined hormonal contraception, progestin-only contraception is not associated with an increase in venous thromboembolism or stroke. Women with migraine are at increased risk of ischaemic stroke. Several studies have reported a reduction in migraine frequency and intensity with desogestrel 75 µg, a progestin-only pill. At present the quality of data is limited by retrospective study designs, lack of control groups and small sample sizes. We present the first prospective nonrandomised controlled trial.

Methods: A total of 150 women with migraine visiting our clinic for contraceptive counselling were screened. The intervention group comprised women who opted for contraception with desogestrel (n?=?98); the control group comprised women who continued their usual contraceptive (n?=?36). Participants completed daily diaries for 90 days before the intervention and 180 days after the intervention.

Results: In the intervention group, we found improvements in migraine frequency (p?<?.001), migraine intensity (p?<?.001) and the number of triptans used (p?<?.001). These improvements were already significant after 90 days of desogestrel use (p?<?.001). Disability scores also decreased significantly. No improvement was seen in the nonintervention group.

Conclusion: These data demonstrate for the first time in a prospective controlled setting that daily use of the progestin desogestrel is associated with a decrease in migraine frequency, migraine intensity and pain medication use in women with migraine, with and without aura, who had previously been experiencing at least three days of migraine per month.

Trial registration: The study is registered in the University of Zürich database (www.research-projects.uzh.ch/unizh.htm).  相似文献   

58.
Laser scanning confocal imaging was used to monitor release of Ca2+ from localized regions in a skeletal muscle cell line with sparsely distributed Ca2+ release sites. The goal was to distinguish between two schemes proposed to explain the phenomenon of “quantal” Ca2+ release from caffeine-sensitive Ca2+ stores in muscle and other tissues: (1) all-or-none (true quantal) Ca2+ release from functionally discrete stores that have different sensitivities to caffeine; or (2) adaptive behavior of individual release sites, each responding transiently and repeatedly to incremental caffeine doses. Our results showed that Ca2+ release induced by K+ or caffeine occurs in discrete loci within the cell. The image areas and fluorescence intensities of some of these evoked local signals were similar to those of Ca2+ sparks that were observed under resting conditions and which are believed to be due to spontaneous activation of single release units. In contrast to the expectations imposed by quantal models, incremental doses of caffeine activated the same sets of release sites throughout the cell. Ca2+ release, at a given site, triggered by a submaximal dose of caffeine was transient and could be reactivated by addition of a higher caffeine dose, showing the same type of adaptive behavior as measured globally from larger areas of the cell. These results suggest that incremental Ca2+ release is accounted for by adaptive behavior of individual Ca2+ release sites. Received: 9 August 1995/Received in revised form and accepted: 13 October 1995  相似文献   
59.
Fifty patients with suspected allergy to penicillin were tested. Skin tests were done with Na-penicillin G and penicilloyl-polylysin. Specific IgE antibody assays were done with penicilloyl G and V conjugates by means of RAST. The overall agreement between skin test and RAST results was 87%, borderline cases not included. In one case, skin tests were positive to penicillamine only, while RAST for penicilloyl G and V both proved to be positive. One case of penicillin allergy could be diagnosed in vitro post mortem only. Two cases of Hoigné syndrome showed no evidence of allergy. Patterns of skin manifestations varied but urticaria was the most commonly seen feature. Twenty patients without adverse reactions to penicillin treatment and seven patients who had not received penicillin over the last 10 years served as controls. None of them were positive in either skin tests of RAST. Two or our twenty control patients developed penicillin allergy during the study. Both showed positive RAST results.  相似文献   
60.
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