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81.
Y Takahashi  T Miura 《Toxicology》1989,56(3):253-262
Male Jcl:Wistar rats were exposed continuously to 0.2 ppm ozone (O3) and 4 ppm nitrogen dioxide (NO2), alone and in combination, for 1 and 2 months to examine the effects of combined gas on the xenobiotic metabolizing systems of lung microsomes. The cytochrome P-450 content increased to 200% and 253% of the control values during 2-month exposures to O3, while it was not increased by NO2 exposures. Addition of NO2 to O3 reduced the increased level of cytochrome P-450 to 179% and 178% of the control values. The activities of cytochrome P-450-dependent monooxygenase, benzo[a]pyrene hydroxylase and 7-ethoxycoumarin O-deethylase were changed in the same fashion by exposures to NO2 and O3. The 7-ethoxycoumarin O-deethylase activity was increased to 147% and 142% of the control values by O3 exposure, whereas it was decreased to 71% and 75% of the control values by NO2 exposures. This activity was decreased to 124% and 97% of the control values by combination of O3 with NO2 after 1 and 2 months, respectively. Similarly, the benzo[a]pyrene hydroxylase activity was increased to 157% and 153% of the control values during O3 exposures, while it was not changed by NO2 exposures. Addition of NO2 to O3 reduced the activity to 140% and 115% of the control values after 1 and 2 months, respectively. The alteration of coumarin hydroxylase activity was different from those of others. This activity decreased to 44% and 29% of the control values after 1- and 2-month exposures to NO2, respectively, and was also decreased by O3 exposures. However, the magnitude of decrease was not reinforced by combination of NO2 with O3. These results indicate that an increased level of xenobiotic metabolizing activity produced by O3 exposures is lowered by combination with NO2. These phenomena may be antagonistic effects of these gases on the xenobiotic metabolizing systems of lung microsomes.  相似文献   
82.
83.
Despite the high prevalence of diabetes mellitus in patients with chronic pancreatitis, few studies of pancreatic diabetes have been reported. We investigated 154 patients with chronic pancreatitis, of whom 50% were diabetics, with special reference to the features and clinical course of pancreatic diabetes. We arrived to clarify the features of pancreatic diabetes by comparing pancreatic exocrine function in 112 patients with primary diabetes with findings in a separate group of 80 patients with chronic pancreatitis. Pancreatic diabetes is proposed as a type of diabetes in which exocrine pancreatic function is markedly decreased. Progressive and fatal angiopathies were found in patients with pancreatic diabetes after a long duration of diabetes. The present investigation suggests that treatment of malnutrition is necessary in patients with pancreatic diabetes and that control of blood glucose is often difficult in these patients because of the high incidence of insulin-induced hypoglycemic episodes. (Received Feb. 6, 1997; accepted July 25, 1997)  相似文献   
84.
Objective: We studied the bronchodilatory effect of tiquizium bromide [3-(di-2-thienylmethylene)-5-methyl-trans-quinolizidinium bromide; TQZ], an antimuscarinic agent, on airway smooth muscle in vitro, and also in patients with chronic obstructive pulmonary disease (COPD). Methods: In the first experiment, canine tracheal smooth muscle was used to measure the pA2 of TQZ in vitro. The selectivity of TQZ for muscarinic receptor subtypes was also examined with a radioligand binding assay. Results: The pA2 value of TQZ was 8.75. The pK i values of TQZ for M1, M2, and M3 were 8.70, 8.94, and 9.11, respectively. In an open pilot experiment, the effects of TQZ inhalation were studied in seven patients with COPD (seven men, mean age 68.5 years). TQZ significantly increased forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1) in a dose-dependent manner. The mean maximum increases in FVC and FEV1 caused by inhaled TQZ (2.0 mg) were 24% and 29%, respectively, and they were measured 1 h after the drug had been inhaled. The FVC and FEV1 were still significantly higher than the control values even 8 h after the drug had been inhaled. No adverse effects were observed after inhalation of TQZ. Conclusion: These data suggest that TQZ is an effective antimuscarinic agent, and that it causes significant bronchodilation in patients with COPD. Received: 3 April 1995/Accepted in revised form: 27 November 1995  相似文献   
85.
We report a metastatic pulmonary tumor resected by video-assisted thoracoscopic surgery. A 63-year-old female was found to have four nodules of hepatocellular carcinoma (HCC) in January 1991; after non-surgical treatment, the tumors had become necrotic. In June 1992, a new HCC nodule was found. After infusion chemotherapy, it became necrotic. In September 1993, a solitary lung tumor, 2.4 cm in diameter, appeared at the periphery of the right lung. Because the tumor was considered to be a metastatic HCC rather than a primary lung cancer, it was removed by thoracoscopic wedge resection. Although whether metastasectomy contributes to prolongation of survival is still controversial, thoracoscopic pulmonary resection may be indicated for solitary peripheral metastasis, if the primary HCC is well controlled by multidisciplinary treatment.  相似文献   
86.
An enzyme-linked immunosorbent assay (ELISA) system for the quantitation of human monocytic colony-stimulating factor (hM-CSF) was established, which was based on the "dual antibody immunometric sandwich" principle using horse and rabbit polyvalent antibodies against human urinary colony-stimulating factor (CSF-HU). The minimal detectable level of hM-CSF was 10 U/mL, and the assays showed good reproducibility. As measured by this method, the average serum hM-CSF level of 20 normal adults was 540 +/- 110 U/mL (range, 300 to 800 U/mL). The peak of hM-CSF measured by ELISA was identical to that measured by bioassay when semipurified CSF-HU was fractionated by reversed-phase high performance liquid chromatography (HPLC). This method detected two types of hM-CSF, which had approximate molecular weights of 85 Kd (CSF-HU) and 45 Kd in human serum and urine; the ratio of 85:45 Kd was very high in serum and the amounts of the two types were nearly equal in urine. After anticancer chemotherapy, the serum hM- CSF level of one half of the patients with hematological malignancy was elevated according to the reduction in neutrophil number, while it was almost in the normal range in the other half of the patients, indicating the possibility that anticancer chemotherapy damaged the hM- CSF-producing cells. This ELISA method may be useful for monitoring the serum hM-CSF level after anticancer chemotherapy.  相似文献   
87.
Summary Four patients with dural arteriovenous malformation (AVMs) draining into the cavernous sinus, who presented ophthalmic manifestations, were studied by magnetic resonance (MR) imaging. In all patients signal decrease in the involved cavernous sinus was demonstrated in coronal spinecho (SE) imaging. It is attributable to rapid venous flow in the sinus, and this high velocity signal loss is a fairly pathognomonic finding in this condition. We stress the validity of MR imaging in the primary diagnosis of dural AVMs with ophthalmic symptoms.  相似文献   
88.
Pneumatic ventricular assist device (VAD) was utilized for cardiogenic shock after intracardiac operation in two children with complex cardiac anomalies based with single ventricle. In the first case (a 10-year-old), after a modified Fontan operation, VAD was placed between the functional left atrium and ascending aorta, serving as a "artificial single ventricle" with neither pumping chamber nor artificial support in the right side of the heart. The systemic circulation was maintained by keeping relatively high central venous pressure. In another child (a 3-year-old) who underwent repair of incompetent atrioventricular valve leaving intracardiac lesions, VAD was placed between the common atrium and ascending aorta, serving as a pump for both pulmonary and systemic circulation with regulation of pulmonary blood flow through an aortopulmonary Gore-Tex shunt. The circulatory assist with VAD was utilized for 5 and 6 days, respectively. Although weaning from the device was not feasible in both patients because of the pulmonary dysfunction, these experience showed the possible use of VAD for cardiogenic shock after surgery in patients with complex cardiac anomalies.  相似文献   
89.
Clonal plants propagated from a single plant of a commercial variety of ANGELICA ACUTILOBA (Umbelliferae) through somatic embryoids induced in cell suspension cultures proved to be significantly more uniform with respect to the contents of medicinally important chemical constituents (ligustilide and choline) of the root when compared with seed-propagated plants.  相似文献   
90.
Mitsukuni Murasaki and Sadanori Miura: The Future of 5-HT1A Receptor Agonists. (Aryl-Piperazine Derivatives) Prog. Neuro- Psychopharmacol-& Biol Psychiat, 1992, 16(6): 833–845.
1. 1. At present the dominant position among anti-anxiety medications has changed from meprobamate to the benzodiazepine derivatives.
2. 2. In order to avoid benzodiazepine's (BZ) undesirable side effects such as impairment of psycho-motor function, memory impairment, low dose dependence and withdrawal symptoms, a third generation anxiolytic agent, buspirone, the focus of the aryl-piperazine group of anti-anxiety agents, has been introduced recently.
3. 3. Aryl-piperazine derivatives work as 5-HT1A receptor partial agonists and are known as serotonin normalizers.
4. 4. Therefore, they are expected to have not only an anxiolytic function but also an anti-depressant effect as well.
5. 5. A characteristic of the aryl-piperazine derivatives is that they have no sedative and muscle relaxant effects, and they do not have BZ's undesirable side-effects, especially in regard to withdrawal symptoms. However they have a rather weak anxiolytic action and a slow onset of action.
6. 6. Aryl-piperazine derivatives will not take the place of BZ, but the use of BZ and buspirone as bridge medications, making the most of the strong points of both, can be proposed as a way to compensate for their respective disadvantages.
Keywords: aryl-piperazine derivatives; future of new anxiolytics; 5-HT1A receptor agonist; nonbenzodiazepine anxiolytic  相似文献   
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