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21.
Absorption of tetrahydropyranyl adriamycin (THP) administered immediately after transurethral resection of bladder carcinoma (TUR-Bt) has not been reported. In this study, we have examined the absorption of THP and the systemic toxicity in the early post-TUR period. Of 21 patients with bladder carcinoma, 10 had a solitary tumor and 11 multiple tumors. Twenty mg THP in 40 ml of sterile water was intravesically administered on days 1, 3, 5, 7, 14 and 28, and then every 4th week. The THP solution was retained for 2 hours. The blood THP concentration was measured 30 minutes and 2 hours after the intravesical administration on days 1, 7 and 28. No systemic side effects were observed. Thirteen of the 38 (34%) samples contained a detectable level (more than 1 ng/ml) of THP on the post-TUR-Bt on day 1, 8, of 42 (19%) on day 7, and 3 of 18 (17%) on day 28. Altogether, 24 of the 98 (24%) samples contained more than 1 ng/ml THP. The highest blood THP level was 23 ng/ml on day 1. The differences between frequency of detection of blood THP in the samples at 30 minutes and 2 hours were not statistically significant. The difference between average concentration of blood THP of patients with solitary and multiple tumors also was not significant. These results indicate that intravesical THP administration starting within 24 hours after TUR-Bt can not result in significant systemic absorption of THP, and the systemic toxicity can be avoided.  相似文献   
22.
1. The effects of acute bilateral superior cervical ganglionectomy on cerebral blood flow and metabolism were investigated in stroke-prone spontaneously hypertensive rats (SHRsp), before and during cerebral ischaemia. 2. The resting cerebral blood flow was comparable between the control and denervated animals. 3. There was no significant difference in cerebral blood flow or concentration of tissue energy metabolites (adenosine triphosphate [ATP], lactate and pyruvate) between the sham-operated control and denervated animals during ischaemia. 4. The results suggest that sympathetic innervation of cerebral vessels originating from superior cervical ganglia may not play a major role in the progression of cerebral ischaemia in SHRsp.  相似文献   
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24.
We report on a family with ataxia type 6 (SCA6) showing peculiar oculomotor symptoms. The proband presented with periodic alternating nystagmus (PAN), and her 2 brothers had rebound nystagmus and gaze-evoked nystagmus. They carried the identical mutation (the number of expanded CAG repeat, 24) in the CACNA1A gene. The intrafamilial variability of oculomotor symptoms may be ascribed to factors other than CAG repeat expansion size in SCA6.  相似文献   
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26.
β2-glycoprotein-I (β2GPI) is a phospholipid-binding plasma protein that consists of five homologous domains. Domain V is distinguished from others by bearing a positively charged lysine cluster and hydrophobic extra C-terminal loop. β2GPI has been known as a natural anticoagulant regulator. β2GPI exerts anticoagulant activity by inhibition of phospholipid-dependent coagulation reactions such as prothrombinase, tenase, and factor XII activation. It also binds factor XI and inhibits its activation. On the other hand, β2GPI inhibits anticoagulant activity of activated protein C. According to the data from knockout mice, β2GPI may contribute to thrombin generation in vivo. Phospholipid-bound β2GPI is one of the major target antigens for antiphospholipid antibodies present in patients with antiphospholipid syndrome (APS). Binding of pathogenic anti-β2GPI antibodies increases the affinity of β2GPI to the cell surface and disrupts the coagulation/fibrinolysis balance on the cell surface. These pathogenic antibodies activate endothelial cells via signal transduction events in the presence of β2GPI. Impaired fibrinolysis has been reported in patients with APS. Using a newly developed chromogenic assay, we demonstrated lower activity of intrinsic fibrinolysis in euglobulin fractions from APS patients. Addition of monoclonal anti-β2GPI antibodies with β2GPI also decreased fibrinolytic activity in this assay system. β2GPI is proteolytically cleaved by plasmin in domain V (nicked β2GPI) and becomes unable to bind to phospholipids, reducing antigenicity against antiphospholipid antibodies. This cleavage occurs in patients with increased fibrinolysis turnover. Nicked β2GPI binds to plasminogen and suppresses plasmin generation in the presence of fibrin, plasminogen, and tissue plasminogen activator (tPA). Thus, nicked β2GPI plays a role in the extrinsic fibrinolysis via a negative feedback pathway loop.  相似文献   
27.
In addition to estrogen widely used all over the world for the prevention of postmenopausal osteoporosis, calcitonin and vitamin D derivatives are commonly employed to treat established osteoporosis at higher age in Japan. In order to critically assess the usefulness of vitamin D derivatives and calcitonin alone or in combination on the advancement of vertebral deformity at higher age, 32 osteoporotic patients with vertebral deformity with the mean age of 79 were randomly divided into 4 groups with indistinguishable age and severity of the vertebral deformity. Group 1 served as the control without specific medications for osteoporosis. Group 2 was treated with 10 units elcatonin (eel calcitonin derivative) injected intramuscularly twice a week. Group 3 was given 0.75 to 1.5μg/day 1α (OH) vitamin D3 orally. Group 4 was given a combination of treatments used in Groups 2 and 3. In the lateral X-ray film of the spine taken prior to the test and every 6 months thereafter, the shape of the vertebral body T8 through L4 was monitored by measuring the anterior, central and posterior heights. Decrease of the vertebral height ratio; anterior or middle height/posterior or adjacent intact posterior height, by more than 20% of the original value or from above to below 0.80 both appeared to be inhibited during administration of 1α (OH) vitamin D3. Such effect seems to be augmented by simultaneous administration of elcatonin. Actual decrease of vertebral height ratio values and the per cent fall from the original value significantly less in Groups 3 and 4 than in Group 1. Development of vertebral deformity assessed by the changes of the vertebral height thus appears to decrease during treatment with 1α (OH) vitamin D3 especially together with calcitonin in established osteoporosis.  相似文献   
28.
Background: The overexpression of p53 has been found to be correlated with prognosis of some carcinomas, including gastric cancer, but no studies have reported on its relationship to the location of gastric cancer. In the present study, we compared the p53 expression of proximal and distal gastric cancer concerning histopathology and prognosis. Methods: A total of 170 tumors in the patients with proximal (80 cases) and distal (90 cases) gastric cancer were studied by immunohistochemical methods. Results: p53 immunopositivity was detected in 28.8% of all tumors. The p53-positive expression in proximal gastric cancer was higher than in distal gastric cancer (38.8% vs. 20.0%, p<0.05). A 5-year survival analysis showed that there is no significant difference between tumors that are p53 positive and p53 negative. No correlation was found between p53 expression and histopathology of gastric cancer. Conclusion: p53 nuclear staining is not useful as a prognostic indicator or as a parameter in gastric cancer.  相似文献   
29.
Changes in cardiac myosin heavy chain (MHC) gene expression and isozyme transitions have been shown to be caused by developmental changes, hemodynamic overload, or the activity of various hormones. In this study, to examine whether caffeine, which has teratogenic effects on the fetal cardiovascular system, causes the distribution of cardiac MHC phenotype and, if so, to evaluate the mechanisms of the distribution of cardiac MHC phenotype by caffeine, we examined the effects of caffeine, theophylline, and cAMP on the cardiac MHC isoform transitions at the gene and protein levels using hypothyroid adult rats. Furthermore, we examined the expression of alpha- and beta-MHC gene in cardiac muscles of fetuses whose dams had received caffeine. The results showed that caffeine, theophylline, and cAMP caused accumulations of alpha-MHC mRNA and MHC isozyme V1. Furthermore, in the fetal hearts, it was recognized that caffeine induced an accumulation of alpha-MHC gene expression, as was also seen in the dams. However, this effect of caffeine on the heart was stronger in the fetus than in the dam. Intracellular cAMP concentration was increased by the administration of caffeine, theophylline, or cAMP, and the levels showed a positive correlation with those of alpha-MHC mRNA. These results suggest that the induction of alpha-MHC mRNA expression by the administration of caffeine may be induced by an increase in intracellular cAMP concentration.  相似文献   
30.
The human lung tumor-derived cell lines A549, Calu-1, Calu-3, HuT292, and SW900 and the transformed human bronchial epithelial cell line TBE-1, that was transfected with the v-Harvey-ras oncogene, were inoculated into deepithelialized Fisher 344 rat tracheas (5 X 10(5) cells/trachea). After the ends of the tracheas were sealed, the tracheas were transplanted into s.c. tissues of nude mice. In a parallel experiment, 1 X 10(6) cells from each of these cell lines were injected s.c. Histological examination of the tracheal transplants 2, 4, 8, 12, and 16 weeks after cell inoculation proved to be of greater usefulness than either clinical or histological observation of the s.c. injection sites. A549, Calu-1, and TBE-1 produced intratracheal neoplastic nodules as early as 2 weeks after cell inoculation. Calu-3, HuT292, and SW900 grew relatively slowly in the tracheas, and simple or stratified epithelia with slight or moderate atypia (preneoplastic lesions) were seen at 2 weeks. After the 4th week, they produced tumor nodules in the tracheal transplants, whereas no tumor cells could be seen at the s.c. injection sites. The human derivation of the cells was confirmed by in situ hybridization using human-specific DNA probes. The intratracheal inoculation and xenotransplantation of human-derived cell lines offers a time-saving alternative to the s.c. inoculation assay for tumorigenicity and is at the same time a potentially valuable approach to studying preneoplastic and neoplastic progression with human cell subpopulations.  相似文献   
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