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991.
992.
OBJECTIVES: We examined whether the adenosine triphosphate (ATP)-sensitive potassium (K(ATP)) channel openers (KCOs) block myocardial hypertrophy and whether the 70-kDa S6 kinase (p70S6K) or extracellular signal-regulated kinase (ERK)-dependent pathway is involved. BACKGROUND: Long-term inhibition of nitric oxide (NO) synthesis induces cardiac hypertrophy independent of blood pressure, by increasing protein synthesis in vivo. The KCOs attenuate calcium overload and confer cardioprotection against ischemic stress, thereby preventing myocardial remodeling. METHODS: Twelve Wistar-Kyoto rat groups underwent eight weeks of the drug treatment in combination with the NO synthase inhibitor N(omega)-nitro-L-arginine methyl ester (L-NAME), the inactive isomer D(omega)-nitro-L-arginine methyl ester, KCOs (nicorandil, 3 and 10 mg/kg per day, or JTV-506, 0.3 mg/kg per day), or the K(ATP) channel blocker glibenclamide. The L-NAME was also used with hydralazine, the p70S6K inhibitor rapamycin, or the mitogen-activated protein kinase inhibitor PD98059. Finally, the left ventricular weight (LVW) to body weight (BW) ratio was quantified, followed by histologic examination and kinase assay. RESULTS: The L-NAME increased blood pressure and LVW/BW, as compared with the control agent. The KCOs and hydralazine equally cancelled the increase in blood pressure, whereas only KCOs blocked the increase in LVW/BW and myocardial hypertrophy induced by L-NAME. The L-NAME group showed both p70S6K and ERK activation in the myocardium (2.3-fold and 2.0-fold increases, respectively), as compared with the control group, which was not reversed by hydralazine. Selective inhibition of either p70S6K or ERK blocked myocardial hypertrophy. The KCOs prevented the increase in activity only of p70S6K. Glibenclamide reversed the effect of nicorandil in the presence of L-NAME. CONCLUSIONS: The KCOs modulate p70S6K, not ERK, to attenuate myocardial hypertrophy induced by long-term inhibition of NO synthesis in vivo.  相似文献   
993.
Miyashita N  Fukano H  Okimoto N  Hara H  Yoshida K  Niki Y  Matsushima T 《Chest》2002,121(6):1776-1781
STUDY OBJECTIVE: To investigate the clinical presentation of community-acquired Chlamydia pneumoniae pneumonia in adults. DESIGN: Prospective study. SETTING: Kawasaki Medical School Hospital, Kawasaki Medical School Kawasaki Hospital, and Kurashiki Daiichi Hospital in Japan. PARTICIPANTS: Forty patients with community-acquired pneumonia with C pneumoniae as the only pathogen identified admitted to three hospitals between April 1996 and March 2001 and their clinical presentations were compared to patients with Streptococcus pneumoniae and Mycoplasma pneumoniae pneumonia. MEASUREMENTS: The diagnosis of C pneumoniae infection was based on isolation and serologic testing of antibodies by the microimmunofluorescence test. RESULTS: The clinical presentations, except for shortness of breath, were similar for the three major etiologic agents. The mean temperature of C pneumoniae patients on hospital admission was 37.9 degrees C, which was lower than that of patients with S pneumoniae and M pneumoniae. The mean WBC count on hospital admission was lower in the patients with C pneumoniae (mean, 9,100/microL) than in those with S pneumoniae pneumonia but higher than in those with M pneumoniae pneumonia. No patients required respiratory support or admission to an ICU, and no deaths occurred among the C pneumoniae pneumonia patients. CONCLUSIONS: Our results indicate that C pneumoniae pneumonia as a single etiologic agent is mild and that the underlying conditions and clinical symptoms closely resemble those of S pneumoniae pneumonia. However, the physical examinations, laboratory findings, and prognostic factors of the C pneumoniae patients resembled those of patients with M pneumoniae pneumonia.  相似文献   
994.
The discovery of the gene for cystic fibrosis (CF), the cystic fibrosis transmembrane conductance regulator (CFTR), brought about a new era in the study of this disease. Identification of the molecular target has yielded a flood of data that add to our understanding of the pathogenesis, diagnosis and treatment of CF. The CFTR protein is a cAMP-regulated Cl(-) channel with multiple functions in epithelial cells. In the exocrine pancreas the CFTR plays a key role in the apical Cl(-), HCO(3)(-), and water transport in duct cells. The severe loss of functions, caused by mutations of the CFTR gene, leads to pathological lesions of the pancreas. Over 1200 CFTR mutations and polymorphisms have been identified and their diversity may explain the high level of heterogeneity in the CF phenotype. Mutation analyses of the CFTR gene have revealed a spectrum of CFTR-related diseases that do not fit the classical CF picture but are associated with dysfunction of CFTR, such as chronic pancreatitis.  相似文献   
995.
Churg-Strauss syndrome (CSS) is characterized by the presence of asthma, eosinophilia, and small-vessel vasculitis with granuloma. It is a distinct entity, as determined from all classifications of systemic vasculitis. The poor prognostic factors in CSS are renal insufficiency, cardiomyopathy, severe gastrointestinal (GI) tract, and central nervous systems (CNS) involvement. The initial management of CSS should include a high dose of a corticosteroid: prednisone at 1 mg/kg/day or its equivalent for methylprednisolone with tapering over 6 months. In patients with severe or rapidly progressing CSS, the administration of methylprednisolone pulse at 1 g/body/day for 3 days is recommended. When corticosteroid therapy does not induce remission, or when patients have poor prognostic factors, immunosuppressive cytotoxic therapy is indicated. However, some patients with severe CSS often show resistance to conventional treatment. We think that IVIG therapy is a hopeful candidate for second-line treatment for CSS patients, particularly in the case of neuropathy and/or cardiomyopathy, which are resistant to conventional therapy. However, there is not much evidence supporting the effectiveness of IVIG in CSS, and the mechanisms underlying the action of IVIG remain unclear. Now we are performing clinical trials of IVIG therapy for CSS patients who are resistant to conventional treatment, through a nationwide double-blinded placebo-controlled study in Japan.  相似文献   
996.
Effects of smoking on white matter lesions, such as lacunar infarction and leukoaraiosis, are still controversial. We hypothesized that the endothelial NO synthase (eNOS) genotype was a modulating factor for the effect of smoking on cerebral circulation. We took a cross-sectional population from the participants of a health examination to study the effects of smoking and a single-nucleotide polymorphism in the eNOS gene, T-786C. Smokers and nonsmokers were defined as having a smoking index (cigarettes per day times years) of >/=200 and 0, respectively. One hundred sixty-six male nonsmokers and 344 male smokers were recruited. Cerebral blood flow was measured by the (133)Xe inhalation method. Genotyping of T-786C was performed by using a newly developed allele-specific polymerase chain reaction. Smokers were exposed to greater oxidative stress, as estimated by urinary F(2)-isoprostane excretion. In smokers, CC homozygotes of T-786C showed a significant decrease of cerebral blood flow (56.6+/-13.3, 57.6+/-11.5, and 44.0+/-7.2 mL/min per 100 g tissue for TT, TC, and CC, respectively; P=0.03 by ANOVA) and a significant increase of cerebrovascular resistance, whereas the eNOS genotype did not affect these parameters in nonsmokers. This result indicated that the eNOS genotype could modify cerebrovascular circulation in a general population by potentiating the adverse effect of smoking.  相似文献   
997.
998.
Background: It is suggested that endotoxin and proinflammatory cytokines play an important role in the development and progression of alcoholic liver disease. Recently, a prostaglandin receptor subtype EP4 agonist with cytoprotective effect has been developed. We examined the efficacy of an EP4 agonist ONO-AE1-437 on tumor necrosis factor-α (TNF-α) secretion of Kupffer cells, splenic macrophages, and alveolar macrophages in acute ethanol-loaded rats.
Methods: Kupffer cells, splenic macrophages, and alveolar macrophages were isolated from control and acute ethanol-loaded rats (5 mg/g body weight of ethanol, intraperitoneally). After the preculture in the medium that containing 0, 0.1, 1, 10, or 100 nmol/liter of ONO-AE1-437, TNF-α secretion of these cells stimulated by 100 ng/ml of endotoxin was determined for 3 hr.
Results: The amount of TNF-α secreted from alveolar macrophages was largest in both the control and the acute ethanol-loaded rats. Acute ethanol load enhances TNF-α secretion of splenic macrophages. The addition of ONO-AE1-437 significantly inhibited TNF-α secretion of Kupffer cells and splenic macrophages in both the control and the acute ethanol-loaded rats. Alveolar macrophages were less affected.
Conclusions: An EP4 agonist ONO-AE1-437 suppresses excess TNF-α secretion from macrophages and seems promising for future trial in patients with severe alcoholic hepatitis.  相似文献   
999.
This study was conducted to identify patterns of carpal instability in the rheumatoid wrist. One hundred patients with proven rheumatoid arthritis were randomly chosen, and posteroanterior and lateral radiographs of right wrists were taken. The most common isolated pattern was volar intercalated segmental instability, apparent in 16 wrists, while nine wrists had scapholunate dissociations. Larsen grading scores revealed a correlation between disease duration, carpal height ratio, and ulnar translocation index. In the early stages of disease, the scapholunate angle was significantly increased and the lunate rotated volarly due to loosening of the intrinsic carpal ligament. In later phases, the capitolunate angle significantly increased and the capitate rotated dorsally. Patterns of carpal instability in rheumatoid wrists seem to be complicated, involving combined laxity of the intrinsic and extrinsic carpal ligaments.No benefits have been received from a commercial party directly or indirectly related to the subject of this article.An erratum to this article can be found at  相似文献   
1000.
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