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101.
The overlapping expression of neurotrophin and neural cytokine receptors indicates that most neuronal populations are responsive to both classes of factors, yet relatively little is known about how these two trophic signaling systems interact to regulate neuronal phenotype. We report here that one hallmark of NGF's effects on target cells, the induction of membrane electrical excitability, requires the intermediary action of a CNTF-like factor. We found that NGF's regulation of voltage-gated potassium channels, unlike its regulation of voltage-gated sodium and calcium channels, involves a CNTF-like autocrine/paracrine loop. We showed that NGF induces secretion of a soluble factor that mimics the action of exogenous CNTF in regulating voltage-gated potassium channels and that NGF's ability to regulate this potassium channel is blocked by three independent reagents that inhibit the signaling of CNTF and/or related factors. The identity of this autocrine factor does not appear to be CNTF itself. Thus, a CNTF-like autocrine/paracrine factor is both necessary and sufficient for the regulation of potassium channels by NGF and is a key determinant of the type of electrical excitability that NGF induces in target cells.  相似文献   
102.
Lee SM  Yip PK  Jeng JS  Lo HJ  Chang M 《Psychiatry research》1999,92(2-3):93-102
Although many regional cerebral blood flow (rCBF) studies of schizophrenic patients have been carried out, only a few studies have investigated real-time hemodynamic changes in schizophrenic patients. In the present study, we used long-term monitoring of the middle cerebral artery (MCA) by non-invasive transcranial Doppler ultrasonography to obtain real-time CBF data in 55 schizophrenic patients and 20 normal comparison subjects. The mean blood flow velocity and pulsatility index (PI) of the MCA were not constant during long-term monitoring. They showed sinusoidal oscillations similar to those described in previous reports. The amplitude variations of these oscillations in both drug-naive and medicated schizophrenic patients were significantly decreased compared with findings in normal control subjects. The averaged PI values were found to be decreased in patients with illness durations of more than 10 years. After withdrawal of antipsychotic medication, both the amplitude variations of oscillations and the PI values in the drug-withdrawn patients were significantly decreased relative to findings in normal control subjects. Our results show a decreased adjustment ability of cerebral vessel resistance not only in neuroleptic-naive schizophrenic patients but also in patients with longer illness duration. Neuroleptics could affect the adjustment ability of vessel resistance.  相似文献   
103.
Ten patients with myotonic muscular dystrophy (MD) were examined by auditory event-related potentials (P300 ERPs), spirometric and blood gas analyses: arterial oxygen tension (PaO2), arterial carbon dioxide tension (PaCO2) and arterial oxygen saturation (SaO2). The aim of the study was to analyse the frequency of ERP abnormalities in this disease and to determine whether the neurophysiological evidence of cognitive impairment might be related to the ventilatory function abnormalities frequently described in MD. The mean P300 latency was significantly altered in MD patients compared with controls; P300 latencies did not correlate with spirometric parameters, blood gas values or with age, age at onset, duration or clinical status of the disease. This study provides neurophysiological evidence of cognitive impairment in MD patients. The cognitive deficits are not related to alveolar hypoventilation and appear to be a non progressive feature of the disease.  相似文献   
104.
Isoeugenolol (1.0, 3.0, 5.0 mg/kg, i.v.) produced a dose-dependent bradycardia and a decrease in blood pressure in anesthetized Wistar rats. Isoeugenolol inhibited the tachycardia effects induced by (-)isoproterenol, but had no blocking effect on the arterial pressor responses induced by (-)phenylephrine. In isolated guinea pig tissues, isoeugenolol antagonized (-)isoproterenol-induced positive inotropic and chronotropic effects on the atria and tracheal relaxations in a concentration-dependent manner. The apparent pA2 values for isoeugenolol on right atria, left atria and trachea were 7.63+/-0.03, 7.89+/-0.12 and 6.12+/-0.05, respectively, indicating that isoeugenolol was a highly selective beta1-adrenoceptor blocker. On the other hand, isoeugenolol produced a mild direct cardiac depression at high concentration and was without intrinsic sympathomimetic activity (ISA). In isolated rat thoracic aorta, isoeugenolol relaxed more potently the contractions induced by (-)phenylephrine (10 microM) and 5-HT (10 microM) than those by high K+ (75 mM). In isolated guinea pig trachea, isoeugenolol attenuated the carbachol (1 microM)-con-tracted trachea more significantly than those contracted with high K+. Furthermore, the binding characteristics of isoeugenolol and various beta-adrenoceptor antagonists were evaluated in [3H]CGP-12177 binding to rat ventricle, lung and interscapular brown adipose tissue (IBAT) membranes. The -log IC50 values of isoeugenolol for predominate beta1-, beta2- and beta3-adrenergic receptor sites were 5.82+/-0.09, 4.74+/-0.05 and 4.73+/-0.12, respectively. In conclusion, isoeugenolol was found to be a highly selective beta1-adrenoceptor antagonist with tracheal and vascular smooth muscle relaxant activities, but was devoid of alpha-adrenoceptor-blocking action.  相似文献   
105.
Davis  GD; Fulton  RE; Ritter  DG; Mair  DD; McGoon  DC 《Radiology》1978,128(1):133-144
Of 181 patients with severe congenital pulmonary atresia and ventricular septal defect or "type IV truncus" (an obsolete term), all but 11% had true central pulmonary arteries. These arteries were demonstrable by large serial biplane angiograms using multiple selective injections into collateral vessels, frequent photographic subtraction, and occasional pulmonary vein-wedge angiograms. These techniques are extremely important for accurate diagnosis and in planning corrective or palliative surgery, which was done in 77% of patients with pulmonary arteries.  相似文献   
106.
107.
The authors discuss the role of surgical treatment in patients with highly malignant soft tissue sarcomas in the limbs. A careful analysis is made of different therapies on the basis of the results obtained by the authors and those reported in the literature. The anatomic classification of lesions is based on functional anatomic compartments, defined as intra- or extracompartmental. If a lesion was within an intrafascial compartment, all the muscles with intact fascial sheaths have up till now been removed "en bloc" to obtain radical margins. Many authors now think that all manifest disease be removed with a generous soft tissue margin on all sides to ensure adequate local treatment. Amputation has commonly been performed for extracompartmental lesions, but a multinodal treatment programme, including limb-sparing resection and tumour-bed radiation, should now be considered if possible in the management of these tumours.  相似文献   
108.
Previously we found that corticosteroid treatment in the hepatitis B virus (HBV)-associated membranous nephropathy (HBVMN) was not associated with a favorable outcome. To distinguish the differences of the HBV DNA in macrophage, T and B cells among HBVMN patients with or without corticosteroid treatment, serial studies at different time points were investigated. HBV DNA appeared as an "episomal" molecule as with 3.2 kb in macrophage, T and B cells. This molecule disappeared after 12 months among HBVMN patients without corticosteroid treatment. HBV DNA, by contrast, appeared as episomal form even three years later in T cells, with frequent proteinuria among HBVMN patients with corticosteroid treatment. This finding indicates that the use of corticosteroids leads to a potential risk of enhancing HBV viral replication in T cells. We studied 24 HBVMN patients who had previously received corticosteroid treatment and had persistent proteinuria, who were administered combination therapy with adenine arabinoside for two weeks and thymic extract (Thymostimulin) for six months to decrease urine protein loss and obtain seroconversion. These 24 patients had heavy (22 of 24, 91.6%) or mild (2 of 24, 8.4%) proteinuria prior to adenine arabinoside and thymostimulin treatment. All 24 patients demonstrated HBV DNA in mononuclear cells and simultaneously exhibited sera positive with HBsAg and HBeAg. In contrast, after treatment only one case (4.2%) had heavy and two cases (8.4%) mild proteinuria; HBV DNA was demonstrated in macrophage (4 of 24, 16.7%), T cells (9 of 24, 37.5%), and B cells (6 of 24, 25%) as well as serum (24 of 24, 100%) prior to treatment.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
109.
The records of 200 patients with generalized cutaneous mycosis fungoides treated with whole body surface electron irradiation were reviewed. Type of skin lesion appeared to be the most important factor with respect to both survival and generalized skin disease-free interval. High-dose irradiation did not seem to influence prognosis significantly compared with a relatively conservative dose. The "cure" rate for the entire group was 7%. For a more homogeneous dose distribution, the eight-field technique is now used instead of the original four-field method. A new formula is proposed to standardize the reporting of doses.  相似文献   
110.
Female C57BL/J6 mice pretreated with dehistonized ependymoblastoma chromatin rejected 5 x 10(4) or 10(5) s.c.-implanted syngeneic ependymoblastoma cells. Control mice that received Freund's adjuvant containing dehistonized chromatin from normal mouse brain developed palpable tumor nodules in 90% and 35 to 45% of the animals, respectively. Increased binding of spleen lymphocytes from mice pretreated with dehistonized tumor chromatin to Sepharose 4B coupled with components of dehistonized tumor chromatin was observed. This provides initial evidence for the presence of "committed" lymphocytes in mice pretreated with dehistonized chromatin from this mouse ependymoblastoma.  相似文献   
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