全文获取类型
收费全文 | 6757篇 |
免费 | 187篇 |
国内免费 | 20篇 |
专业分类
耳鼻咽喉 | 201篇 |
儿科学 | 267篇 |
妇产科学 | 368篇 |
基础医学 | 1031篇 |
口腔科学 | 93篇 |
临床医学 | 362篇 |
内科学 | 1222篇 |
皮肤病学 | 112篇 |
神经病学 | 474篇 |
特种医学 | 144篇 |
外科学 | 759篇 |
综合类 | 28篇 |
一般理论 | 1篇 |
预防医学 | 534篇 |
眼科学 | 277篇 |
药学 | 796篇 |
中国医学 | 6篇 |
肿瘤学 | 289篇 |
出版年
2023年 | 24篇 |
2022年 | 93篇 |
2021年 | 175篇 |
2020年 | 65篇 |
2019年 | 107篇 |
2018年 | 162篇 |
2017年 | 122篇 |
2016年 | 135篇 |
2015年 | 159篇 |
2014年 | 225篇 |
2013年 | 278篇 |
2012年 | 465篇 |
2011年 | 495篇 |
2010年 | 236篇 |
2009年 | 161篇 |
2008年 | 324篇 |
2007年 | 322篇 |
2006年 | 408篇 |
2005年 | 357篇 |
2004年 | 418篇 |
2003年 | 356篇 |
2002年 | 316篇 |
2001年 | 163篇 |
2000年 | 189篇 |
1999年 | 128篇 |
1998年 | 37篇 |
1997年 | 20篇 |
1992年 | 29篇 |
1991年 | 64篇 |
1990年 | 79篇 |
1989年 | 62篇 |
1988年 | 67篇 |
1987年 | 47篇 |
1986年 | 62篇 |
1985年 | 58篇 |
1984年 | 34篇 |
1983年 | 34篇 |
1980年 | 20篇 |
1979年 | 38篇 |
1978年 | 32篇 |
1977年 | 25篇 |
1976年 | 27篇 |
1975年 | 46篇 |
1974年 | 30篇 |
1973年 | 23篇 |
1971年 | 18篇 |
1970年 | 22篇 |
1969年 | 23篇 |
1967年 | 21篇 |
1966年 | 23篇 |
排序方式: 共有6964条查询结果,搜索用时 31 毫秒
71.
V V Bo?ko D E Nemirovski? V V Turygin 《Sovetskoe zdravookhranenie / Ministerstvo zdravookhranenii?a SSSR》1991,(7):43-47
Using special survey questionnaires industrial problems were identified which directly or indirectly determine healthy lifestyle of workers at the Leningrad spinning factory "Red Thread". Difficulties, efforts and potential opportunities to solve these problems were determined with the assistance of administration and public, and also the reasons for ++shrinking of different authorities from the solution of some problems. The apparent divergences in the assessment of problems by different authorities and the necessary attribution of responsibility for their solution require special instructions for the practice of healthy lifestyle formation. 相似文献
72.
H.-J. Ruoff M. Wagner Christine Günther S. Maśliński 《Naunyn-Schmiedeberg's archives of pharmacology》1982,320(2):175-181
Summary Adrenergic stimulation of the adenylate cyclase (AC)-cAMP-system and 14C-aminopyrine accumulation, an indirect measure of parietal cell H+-production, was studied in different preparations of gastric mucosal cells.The 2-adrenoceptor agonist hexoprenaline activated AC of crude homogenates from the gastric corpus of mouse, rat, guinea-pig, hog, dog and man. In isolated rat gastric cells (20% parietal cells), treated by low power sonication, 10–8 to 10–3 mol/l adrenaline and hexoprenaline activated AC equally potently and efficaciously by maximally 170%. Isoprenaline proved to be less effective activating up to 80%. 5·10–5 mol/l GMP-PNP augmented basal activity 8.5 times and reduced the maximal efficacy. Adrenaline and hexoprenaline activated AC by maximally 120%, isoprenaline by 40%. The potency of adrenaline was 4 times lower, that of hexoprenaline 2 and that of isoprenaline 4 times higher in the presence of GMP-PNP. Adrenergic stimulation was inhibited by the -adrenoceptor antagonist propranolol, the effect of -adrenoceptor-blockade by phenoxybenzamine was less pronounced. In fractions with 7–80% of parietal cells, prepared by isopycnic centrifugation with Percoll, adrenaline and hexoprenaline activated AC or hexoprenaline enhanced the cellular level of cAMP in parietal cell poor and rich fractions. The degree of activation in response to histamine correlated with the number of parietal cells.
14C-Aminopyrine uptake was increasingly stimulated through 10–8 to 10–5 mol/l hexoprenaline, maximally by doubling the basal accumulation. 10–4 mol/l histamine was 8 times more effective. 3·10–7 mol/l propranolol inhibited the effect of 10–5 mol/l hexoprenaline by 80%.The data suggest the localization of -adrenoceptors (likely -adrenoceptor) on parietal and other nonidentified gastric cells. At the parietal cell, adrenaline and hexoprenaline initiate activation of AC and hexoprenaline leads to H+-production. The responses are small compared to the effect of histamine. Thus, -adrenoceptor agonists exert intrinsic activity in relation to H+-production. Their influence on stimulated secretion of isolated cells remains to be elucidated. 相似文献
73.
Ostapowicz A Zejmo M Wrześniewska J Białecka M Górnik W Gawrońska-Szklarz B 《Psychiatria polska》2000,34(4):595-605
Modern pharmacotherapy is based on precise adjustment of a dosage schedule to individual requirements of patient. Therapeutic drug monitoring is a method that allows for a more effective treatment approach, especially in the case of a narrow therapeutic index of a drug. Tricyclic antidepressant drugs are characterised by narrow therapeutic index as well as relationship between serum drug concentration and side effects. It was demonstrated that interindividual variability of blood concentrations of tricyclic antidepressant drugs is related to genetic polymorphism of oxidating enzymes participating in metabolism of these drugs. The aim of the study was to estimate the impact of therapeutic drug monitoring of tricyclic antidepressant drugs as well as genotyping on efficacy and safety of endogenous depression therapy. The study included 9 patients with established diagnosis of endogenous depression. Blood serum concentrations of amitryptyline was measured by fluorescence polarisation immune assay (FPIA, Abbott system). Genotype of cytochrome P450 isoenzyme CYP2D6 was determined using PCR-RFLP method. It was demonstrated that monitoring therapy of tricyclic antidepressant drugs in combination with determination of the genotype seems to be more safe and effective. Monitoring therapy and genotyping may be less expensive than the costs of prolonged hospitalisation and risk of side effects. 相似文献
74.
Lamotrigine is a broad-spectrum antiepileptic drug which is thought to act in part via a use-dependent blockade of voltage-sensitive sodium channels to stabilise the neuronal membrane. This results in the inhibition of the excessive release of excitatory amino acids, such as glutamate, during epileptic activity. An open, multicentre, prospective trial of lamotrigine was carried out in adult patients with drug-resistant epilepsy on monotherapy with carbamazepine or valproate. The primary aim of the study was to assess add-on lamotrigine withdrawing to monotherapy. 28-week clinical trial was divided into 4 phases: (1) Dose escalation period (4 weeks), (2) Add-on period (8 weeks), (3) Standard AED withdrawal period (8 weeks), (4) Lamotrigine monotherapy (8 weeks). Thirty-three patients were previously treated with valproate, 44 with carbamazepine. Of 77 patients recruited into the study, 64 patients (83%) completed add-on therapy, 49 patients (64%) completed lamotrigine monotherapy. 44% of all patients during the add-on phase and 48% during lamotrigine monotherapy had a reduction in seizure frequency of at least 50% compared with pre-study period. 13% of all patients achieved seizure freedom during add-on therapy and 18% during monotherapy. Improvement of Visual Analogue Scale (VAS) scores was observed in 65% and 57% patients respectively. A significant proportion of patients could be successfully converted to lamotrigine monotherapy. Lamotrigine was also generally well tolerated. 23 patients (30%) had at least one adverse event (AE), but only 1/4 of all AEs might be reasonably regarded as an effect of the medication. 7 patients (9%) discontinued prematurely from the study due to adverse event. More AEs were observed in add-on therapy than in lamotrigine monotherapy. The safety profile was consistent with that seen during other clinical trials with lamotrigine. CONCLUSIONS: 1. Lamotrigine is effective AED in add-on and monotherapy (responders rate--44% and 48% respectively). 2. In most cases conversion from add-on therapy to monotherapy can be done successfully. 3. Lamotrigine is a safe and well-tolerated drug. 相似文献
75.
Association between the risk for lung adenocarcinoma and a (-4) G-to-A polymorphism in the XPA gene.
Dorota Butkiewicz Odilia Popanda Angela Risch Lutz Edler Hendrik Dienemann Volker Schulz Klaus Kayser Peter Drings Helmut Bartsch Peter Schmezer 《Cancer epidemiology, biomarkers & prevention》2004,13(12):2242-2246
Polymorphisms of genes coding for DNA repair can affect lung cancer risk. A common single nucleotide (-4) G-to-A polymorphism was identified previously in the 5' untranslated region of the XPA gene. In a case-control study in European Caucasians, the influence of this polymorphism on primary lung cancer risk overall and according to histologic subtypes was investigated. Four hundred sixty-three lung cancer cases (including 204 adenocarcinoma and 212 squamous cell carcinoma) and 460 tumor-free hospital controls were investigated using PCR amplification and melting point analysis of sequence-specific hybridization probes. Odds ratios (OR) were calculated by multiple logistic regression analysis adjusting for age, gender, smoking habits, and occupational exposure and showed a slightly enhanced risk for all lung cancer cases as well as for squamous cell carcinoma and adenocarcinoma cases. Gene-environment interactions were analyzed with respect to smoking and occupational exposure. A nearly 3-fold increased risk for adenocarcinoma associated with the XPA AA genotype was observed for occupationally exposed individuals (OR, 2.95; 95% confidence interval, 1.42-6.14) and for heavy smokers (OR, 2.52; 95% confidence interval, 1.17-5.42). No genotype-dependent increase in OR was found for nonexposed individuals or those smoking <20 pack-years. The significant effect of the XPA polymorphism in heavy smokers and occupationally exposed individuals suggests an important gene-environment interaction for the XPA gene. The underlying mechanisms as to why AA homozygotes are predisposed to lung adenocarcinoma and which specific carcinogens are involved remains to be determined. 相似文献
76.
77.
Malcolm S Reid Burt Angrist Sherryl A Baker Siobhan O'leary Jennifer Stone Marion Schwartz Deborah Leiderman Ann Montgomery Ahmed Elkashef Dorota Majewska James Robinson John Rotrosen 《Substance Abuse》2005,26(2):5-14
A placebo controlled, double-blind trial of mecamylamine treatment of cocaine dependence was performed in methadone or LAAM maintained subjects who met DSM-IV criteria for cocaine dependence. After an eight-week placebo run-in screening period, 35 subjects were randomly assigned to receive either mecamylamine (6 mg/day) or placebo transdermal patches for a 16-week treatment period. Outcome measures included quantitative urine benzoylecognine (BE) levels, self-report of cocaine use, cocaine craving, global impression scores, mood, retention, and safety. Mecamylamine was well tolerated, and study retention did not differ by treatment group. Evidence for cocaine use, based on urine BE levels and cocaine abstinence rates, did not differ by treatment group. Self reported cocaine use, cocaine craving, and global impression scores showed moderate improvement in both groups, with a significantly greater reduction in cocaine craving (p < 0.05) and self-rated severity of cocaine dependence (p < 0.05) in the placebo group. This pilot study does not support the effectiveness of mecamylamine for the treatment of cocaine dependence in methadone or LAAM maintained patients. 相似文献
78.
Leszek Satora Dorota Pach Beata Butryn Piotr Hydzik Barbara Balicka-Slusarczyk 《Toxicon》2005,45(7):941-943
Gathering and eating mushrooms and other plants containing psychoactive substances has become increasingly popular among young people experimenting with drugs. Dried fly agaric Amanita muscaria fruiting bodies were eaten by five young persons (18-21 years of age) at a party in order to evoke hallucinations. Visual and auditory hallucinations occurred in four of them, whereas a 18-year-old girl lost consciousness. The following morning, she went to the Clinic of Toxicology. Due to the fact that not all the active substances present in the fly agaric have been identified, and some of them have an effect after a period of latency, the patient was admitted for several days of observation during which check-up examinations were performed. After four days without any problems, she was discharged. The poisoning regressed with no organ complications. The remaining persons who had eaten the fly agaric were free from any complaints. 相似文献
79.
Zaĭtsev VT Boĭko VV Taraban IA Khbus A Boĭko LA Fadzher ZA 《Klinichna khirurhiia / Ministerstvo okhorony zdorov'ia Ukra?ny, Naukove tovarystvo khirurhiv Ukra?ny》2000,(2):8-9
The results of performance of intraoperative rheopancreatography in 8 patients, operated on for an ulcer disease, were presented. The performance of selective proximal vagotomy and sympathectomy of a mesenterica superior had promoted the pancreatic blood flow improvement. It is substantiated in patients with secondary chronic pancreatitis, caused by the ulcer disease. 相似文献
80.