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11.
BACKGROUND: Airway inflammation is a characteristic feature of bronchial asthma. Previous studies have shown an increased local inflammatory activity in the airway mucosa of asthma patients. OBJECTIVES: To analyze the association of asthma with three sensitive markers of systemic inflammation, C-reactive protein, serum amyloid-A (SAA), and plasma fibrinogen. METHODS: A cross-sectional, population-based study including 1,513 Finnish men aged 45 to 74 years, who participated in a chronic disease risk factor survey in 1997. Of the participating men, 97 were classified as asthma patients. The odds ratios of asthma were analyzed by quartile of each inflammation marker. RESULTS: In logistic regression models the age-adjusted odds ratios (second, third, and fourth quartile as compared with the first quartile) of asthma increased gradually with increasing quartile of C-reactive protein (1.28, 1.19, 1.96, P for trend = 0.039), SAA (1.20, 3.00, 3.49, P for trend < 0.001), and fibrinogen (1.22, 1.79, 3.16, P for trend < 0.001). The associations were independent of smoking. Further adjustment for waist-to-hip ratio, a marker of central obesity, and symptoms of chronic bronchitis weakened the observed association, but the increasing trend in the association of SAA and fibrinogen with asthma remained highly significant. CONCLUSIONS: Sensitive markers of systemic inflammation, particularly SAA and fibrinogen, were positively and significantly associated with asthma prevalence. These findings support the hypothesis that not only local, but also systemic, inflammation exist in bronchial asthma.  相似文献   
12.
1 The reproducibility of angiotensin converting enzyme inhibitor induced cough was examined in a double-blind cross over study in patients previously shown to have exhibited this side effect.

2 Ninety-seven patients who had experienced angiotensin converting enzyme inhibitor cough within the last 2 years were challenged with enalapril 20 mg daily for 4 weeks to establish eligibility. Eighty-eight of 97 (91%) patients experienced a repeat of their cough symptoms. Sixty-four patients entered the double-blind part of the study where they were treated with enalapril 20 mg and a renin inhibitor for up to 4 weeks in random order. These periods were separated by a minimum 4 week placebo wash out.

3 Of 59 evaluable patients who received enalapril a second time, 37 (62.7%) experienced cough again. Of 62 patients on the renin inhibitor 16 (25.8%) experienced cough, however as it was not equi-efficacious to enalapril no valid comparison could be made.

4 Angiotensin converting enzyme inhibitor cough is not reproducible within patients, as other factors are involved in the aetiology. Objective testing with blinded assessment together with symptom reporting, would give a more accurate measure of the incidence, and mechanism of this side effect.

  相似文献   
13.
Of 70 cycles stimulated with clomiphene and human menopausal gonadotropin (hMG) for an in vitro fertilization-embryo transfer (IVF-ET) program, a short luteal phase of 11 days or less was found in 18. In this group the mean estradiol and progesterone levels were elevated in the early luteal phase. Despite the elevated initial values, progesterone levels fell rapidly at the mid luteal phase as a sign of premature luteolysis. The mean total amount of gonadotropin administered and the mean number of follicles punctured and of oocytes recovered did not show any significant difference between the groups of normal and short luteal phases. The present findings support the theory that hyperestrogenism in the early luteal phase may initiate the premature luteolysis observed in clomiphene-menopausal gonadotropin-stimulated cycles.  相似文献   
14.
Depression-executive dysfunction syndrome in stroke patients.   总被引:6,自引:0,他引:6  
OBJECTIVE: It has been suggested that executive dysfunction could be the core defect in patients with geriatric or vascular depression, and that this depression-dysexecutive syndrome (DES) might be related to frontal-subcortical circuit dysfunction. The authors tested this hypothesis in 158 poststroke patients, of whom 21 had both depression and executive dysfunction. Methods: In this cross-sectional cohort study, a neurological, psychiatric, and neuropsychological examination was carried out 3 months after ischemic stroke, and brain infarcts, white-matter changes, and brain atrophy were recorded by MRI. RESULTS: The 21 patients with DES had significantly more brain infarcts affecting their frontal-subcortical circuit structures than the 137 patients without DES, or the 41 patients with depression but without executive dysfunction. Patients with DES also had more severe depressive symptoms and worse psychosocial functioning, and they coped less well in complex activities of daily living. CONCLUSIONS: DES is a valid concept and may define a subgroup of poststroke patients with frontal-subcortical pathology and with distinct prognosis and treatment options.  相似文献   
15.
BACKGROUND: Aortic arch operations in pediatric patients using low-flow perfusion techniques have been standardized to a certain degree, but some of the often-stated beneficial effects have never been proven. Especially, the existence or efficacy of any subdiaphragmal perfusion still remains unclear. METHODS: Twenty-six newborn male piglets (10-15 kg) underwent aortic arch surgery under general anesthesia using either low-flow perfusion via the innominate artery (LF, 30 ml/(kg min), 25 degrees C, n=12) or conventional deep hypothermic circulatory arrest (DHCA, 20 degrees C, n=14). Cortical somatosensory-evoked potentials (SSEPs), carotid, and subdiaphragmal blood flows were measured. The animals of both groups have been randomized to either pH-stat or alpha-stat management on cardiopulmonary bypass (CPB). RESULTS: During low-flow perfusion via the innominate artery only negligible flows of maximum 1-3 ml/min in the femoral arteries were detected, whereas the right carotid artery flow doubled. During reperfusion, serum-lactate and aspartate amino-transferase (AST) levels were significantly higher compared to the circulatory arrest group, whereas alanine amino-transferase (ALT), gamma-glutamyl transpeptidase (gamma-GT), AP, and creatinine did not show any significant differences. Cortical SSEP returned to preoperative values in all but two low-flow animals. There was no return of SSEP in all piglets operated under deep hypothermic circulatory arrest (p<0.01). CONCLUSION: Compared to DHCA, low-flow perfusion via the innominate artery provides superior neuroprotection despite higher tissue temperatures. Although collateral blood flow via the subclavian artery and the circulus arteriosus willisii has often been presumed, only 'trickle-flow' with some protective potential was detectable in the femoral arteries during low-flow perfusion. Origin of elevated lactate and AST levels seems to be the lower limbs.  相似文献   
16.
DNA "fingerprint" (DNA-F) analysis, based on the polymorphism caused by numeric variations in the tandem repeats of minisatellite areas of the human genome, has a potential capacity to reveal even minor genomic changes. In this study we have applied DNA-F to the detection of residual disease in leukemia. In order to identify normal and leukemic cell populations, we used two molecular probes: Jeffrey's minisatellite probes and M13 wild type phage probe, which detect different sets of polymorphic fragments in the human genome. Comparison of varying minisatellite fragments between remission and relapse was performed by Southern blot hybridization in seven patients with acute lymphoblastic leukemia (ALL). The results suggest that Southern hybridization with DNA "fingerprint" probes can prove to be a sensitive method in the detection of minimal residual disease in ALL.  相似文献   
17.
BACKGROUND: We report on IgE-mediated allergy in a worker caused by Tribolium confusum (confused flour beetle). These beetles lived in the "old" flour to which he was exposed in his work. CASE REPORT: A 35-year-old, nonatopic mechanic in a rye crispbread factory developed rhinitis, conjunctivitis, and asthmatic symptoms, as well as urticaria on his wrists, lower arms, hands, neck, and face, during the maintenance and repair of machines contaminated by flour. This flour had been in and on the machines for a long time, and it contained small beetles. The patient did not suffer any symptoms when handling fresh, clean flour. RESULTS: Skin prick tests with standard environmental allergens, storage mites, enzymes, flours, and molds were negative. A prick test with flour from the machines gave a 10-mm reaction. An open application of the same flour caused urticarial whealing on the exposed skin. Prick tests with fresh flour from the factory were negative. A prick test with minced T. confusum from the flour in the machines gave a 7-mm reaction. Histamine hydrochloride 10 mg/ml gave a 7-mm reaction. Specific serum IgE antibodies to T. confusum were elevated at 17.2 kU/l. Prick tests with the flour from the machines were negative in five control patients. CONCLUSIONS: The patient had occupational contact urticaria, rhinitis, conjunctivitis, and asthmatic symptoms from exposure to flour. His symptoms were caused by immediate allergy to the beetle T. confusum. Immediate allergy to this beetle has rarely been reported in connection with respiratory symptoms, but it may be more common. Contact urticaria from this source has not been reported before.  相似文献   
18.
Chronic Allograft Rejection   总被引:3,自引:0,他引:3  
  相似文献   
19.
Summary: Ethylene–propylene (EP) copolymerisations were performed with two sterically different metallocenes activated by methylaluminoxane (MAO) in an attempt to better understand the effect of catalyst structure on termination reactions and polymer microstructure. The metallocene precursors under investigation were rac‐dimethylsilylbis(2‐methyl‐4‐phenyl‐1‐indenyl)zirconium dichloride ( 1 ) and a more sterically hindered counterpart rac‐dimethylsilylbis(2‐isopropyl‐4‐[3,5‐dimethylphenyl]indenyl) zirconium dichloride ( 2 ). For both catalyst systems, the most common termination mechanism was chain transfer to aluminium. In addition, for polymer samples polymerised with 1 /MAO, chain growth was terminated by chain transfer to Zr metal in propylene‐rich polymerisations and by chain transfer to ethylene monomer in ethylene‐rich polymerisations. The steric hindrance of 2 was able to suppress the chain transfer to the ethylene monomer, and chain transfer to Zr metal was also found in the ethylene‐rich polymerisations. The greater steric hindrance of 2 also affected the EP copolymer microstructure: regioregularity in the propylene‐rich copolymers was greater and isotacticity less with 2 /MAO than with 1 /MAO.

The catalyst precursors used: rac‐dimethylsilylbis(2‐methyl‐4‐phenyl‐1‐indenyl)zirconium dichloride ( 1 ) and rac‐dimethylsilylbis(2‐isopropyl‐4‐[3,5‐dimethylphenyl]indenyl) zirconium dichloride ( 2 ).  相似文献   

20.
The omptins are a family of enterobacterial surface proteases/adhesins that share high sequence identity and a conserved beta-barrel fold in the outer membrane. The omptins are multifunctional, and the individual omptins exhibit differing virulence-associated functions. The Pla plasminogen activator of Yersinia pestis contributes by several mechanisms to bacterial invasiveness and the systemic, uncontrolled proteolysis in plague. Pla proteolytically activates the human proenzyme plasminogen and inactivates the antiprotease alpha2-antiplasmin, and its binding to laminin localizes the uncontrolled plasmin activity onto basement membranes. These properties enhance bacterial migration through tissue barriers. Pla also degrades circulating complement proteins and functions in bacterial invasion into human epithelial cells. PgtE of Salmonella enterica and OmpT of Escherichia coli have been shown to degrade cationic antimicrobial peptides from epithelial cells or macrophages. PgtE and SopA of Shigella flexneri appear important in the intracellular phases of salmonellosis and shigellosis, whereas functions of OmpT have mainly been associated with protein degradation in E. coli cells. The differing virulence roles and functions have been attributed to minor sequence variations at the surface-exposed regions important for substrate recognition, to the dependence of omptin functions on lipopolysaccharide, and to the different regulation of omptin expression.  相似文献   
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