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91.
beta-Endorphin (beta-E) immunoreactivity was measured in the amniotic compartment of 52 normotensive and 45 hypertensive gestations. All the fetuses of the normal group were healthy and showed appropriate intrauterine growth, whereas only suffering and growth-retarded fetuses were included in the pathological group. As expected, amniotic beta-E concentration was found to be significantly higher in hypertensive than in normotensive pregnancies (mean +/- SEM: 129.1 +/- 8.15 vs. 59.1 +/- 2.68 pg/ml; p < or = 0.005). A positive correlation between the hormone levels and the diastolic as well as the mean maternal blood pressure (r: 0.554; p < or = 0.05 and r: 0.525; p < or = 0.05, respectively) was present only in pregnancies complicated by hypertension. Furthermore, a negative correlation (r: -0.555; p < or = 0.05) linked amniotic beta-E and the pulse pressure in normal but not in complicated pregnancies. Unless beta-E in the amniotic compartment is also of amniochorial origin, our results suggest that the fetal endorphinergic tone is either activated by elevated diastolic and mean maternal pressure levels or lowered by increased pulse pressure values in normally elapsing pregnancies.  相似文献   
92.
Beta-Thalassaemia types in southern Sardinia.   总被引:1,自引:0,他引:1       下载免费PDF全文
In this study the prevalence of the different beta-thalassaemia types in southern Sardinia was investigated by cellulose acetate and agar gel electrophoresis or globin chain synthesis analysis on column chromatography or both in (1) all the patients (347) presenting with thalassaemia major or intermedia at our haematology service from 1976 to 1979, and (2) a group of 82 patients with transfusion-dependent thalassaemia major randomly chosen from 236 under our care. Apart from six subjects with delta(beta)0/beta+-thalassaemia genotype and eight with beta0/beta+ or less probably beta+/beta/-thalassaemia, all thalassaemia major and intermedia patients studied were beta0-thalassaemia homozygotes. Globin chain synthesis on peripheral blood cells from these patients, performed at different intervals from blood transfusion, showed no incorporation of radioactive leucine into beta-globin peak, the same as before the transfusion. No correlation between kappa/gamma ratios and clinical severity or hypersplenism was found. Globin chain synthesis analysis carried out at birth in three infants later found to have homozygous beta0-thalassaemia demonstrated imbalanced or borderline kappa/gamma ratios.  相似文献   
93.
In some clinical trials, treatment allocation on a patient level is not feasible, and whole groups or clusters of patients are allocated to the same treatment. If, for example, a clinical trial is investigating the efficacy of various patient coaching methods and randomization is done on a patient level, then patients who are receiving different methods may come into contact with each other and influence each other. This would create contamination of the treatment effects. Such bias might be prevented by randomization on the coaches level. The patients of a coach constitute a cluster and all the subjects in that cluster receive the same treatment. Disadvantages of this approach may be reduced statistical efficiency and recruitment bias, as the treatment that a subject will receive is known in advance. Pseudo cluster randomization avoids this, because in pseudo cluster randomization, not everybody in a certain cluster receives the same treatment, just the majority. There are two groups of clusters: in one group the majority of subjects receive treatment A, while a limited number receive treatment B. In the other group of clusters the proportions are reversed. The statistical properties of this method are described. When contamination is present, the method appears to be more efficient than randomization on a patient level or on a cluster level.  相似文献   
94.
OBJECTIVES: The aim of this experiment was to detect pressure pain threshold (PPT) differences on intra-oral palpation of the lateral pterygoid muscle (LPM) between subjects diagnosed with temporomandibular disorders (TMD) and controls. METHODS: Thirty-one consecutive female TMD patients and 31 age and gender matched controls underwent palpation of the LPM using an algometer made with a queue-tip connected to a digital scale, and PPT was measured. RESULTS: Mean PPTs of the right and left LPM of the controls were respectively 191g (49KPa) and 200g (51KPa), and mean PPTs of the right and left LPM of TMD patients were respectively 245g (62KPa) and 256g (63KPa). ANOVA between the four PPT measurements showed significant difference only between the PPT readings of the right LPM of the controls and the left LPM of the patients (p<0.05). CONCLUSIONS: The findings of this study suggest that PPT measured by means of the described algometer is not decreased in TMD patients as compared to control subjects.  相似文献   
95.
The effect of PD-168077 (N-methyl-4-(2-cyanophenyl)piperazynil-3-methylbenzamide maleate), a selective D4 dopamine receptor agonist, injected into the paraventricular nucleus of the hypothalamus on penile erection was studied in male rats. PD-168077 (1-200 ng) induced penile erection in a dose-dependent manner. The minimal effective dose was 50 ng, while the maximal response was found with 200 ng of the compound, which increased penile erection episodes from 0.3+/-0.03 to 1.7+/-0.21. The proerectile effect of PD-168077 was reduced almost completely by L-745,870 (3-(4-[chlorophenyl]piperazin-1-yl)-methyl-1H-pyrrolo[2,3-B]pyridine trihydrochloride), a selective D4 dopamine receptor antagonist, (1 microg) given into the paraventricular nucleus before the D4 dopamine agonist, and by other nonselective dopamine receptor antagonists, such as haloperidol (1 microg) and clozapine (1 microg), which block all dopamine receptor subtypes. The pro-erectile effect of PD-168077 was also reduced by the NO synthase inhibitor NG-nitro-L-arginine methylester (25 microg), but not by the oxytocin receptor antagonist d(CH2)5Tyr(Me)2-Orn8-vasotocin (1 microg), when given into the paraventricular nucleus. In spite of its inability to prevent the pro-erectile effect of PD-168077 when given in the paraventricular nucleus, d(CH2)5Tyr(Me)2-Orn8-vasotocin (1 microg) reduced almost completely PD-168077-induced penile erection when given into the lateral ventricles. The present results show that D4 dopamine receptors present in the paraventricular nucleus may influence penile erection by modulating the activity of paraventricular oxytocinergic neurons mediating erectile function.  相似文献   
96.
We studied the genotype/phenotype correlation in a cohort of glycogen storage disease type (GSD) 1b patients. A total of 25 GSD1b patients, 13 females and 12 males, age range: 4.3–28.4 years, mean:14.6±6.8 years; median: 15 years, representing the entire case load of Italian GSD1b patients, were enrolled in the study. Molecular analysis of the glucose 6-phosphate translocase (G6PT1) gene was performed in all patients. We analysed the presence of a correlation among both the clinical features associated with GSD1b (neutropenia, frequency of admission to the hospital for severe infections) and the presence of systemic complications (liver adenomas, nephropathy, bone mineral density defect, polycystic ovaries, short stature, inflammatory bowel disease) and the mutations detected in each patient. Nine patients were homozygous or compound heterozygous for mutations causing stop codons. In particular, three patients were homozygous for the same mutation (400X); of these patients, one showed chronic neutropenia with severe and frequent infections and severe inflammatory bowel disease, another patient cyclic neutropenia associated with rare bacterial infections and mild bowel involvement and the last one normal neutrophil count. Two patients were homozygous for the mutation 128X; one of these patients did not show neutropenia, whereas the other one had severe neutropenia needing frequent hospital admission and was under granulocyte-colony stimulating factor treatment. In three patients no mutations were detected. Conclusion:no correlation was found between individual mutations and the presence of neutropenia, bacterial infections and systemic complications. These results suggest that different genes and proteins modulate neutrophil differentiation, maturation and apoptosis and thus the severity and frequency of infections. The absence of detectable mutations in three patients could suggest that a second protein plays a role in microsomal phosphate transport.  相似文献   
97.
OBJECTIVES: The aim of this study was to evaluate the prevalence of C-shaped canals in single rooted mandibular second molars with spiral computed tomographic imaging in detail. METHODS: One hundred and twelve single-rooted mandibular second molar samples were selected from 491 extracted mandibular second molars. The teeth were scanned by spiral computed tomographic technique to examine canal configurations. RESULTS: The evaluation criteria of the shape of roots was based on Manning's category as round, oval and C-shaped. The prevalence of C-shaped canals was found to be 8.1% in mandibular second molars. The evaluation of the root canal configurations of C-shaped mandibular second molars with single roots (40 teeth) was based on Vertucci's classification. Vertucci type I canals were most frequently seen in C-shaped mandibular second molars (40%). Additionally, we disclosed three additional canal types. CONCLUSION: Results of this study demonstrated that high resolution visualization of the root canal shape can be achieved by spiral computed tomographic imaging.  相似文献   
98.
STUDY OBJECTIVE: To evaluate the clinical efficacy and patient satisfaction of long-term danazol delivered vaginally as treatment for heavy menstrual bleeding. DESIGN: Prospective study (Canadian Task Force classification II-3). SETTING: University hospital. PATIENTS: Twenty premenopausal women with endometrial hyperplasia or endometrial polyps. INTERVENTION: After curettage or hysteroscopic-directed biopsies, women used one 200-mg tablet of danazol vaginally every day, continuing the therapy as long as they were totally satisfied with it. MEASUREMENTS AND MAIN RESULTS: Women were instructed to keep a diary of menstrual bleeding and to rate blood loss on a visual analog scale from zero (no blood loss) to 10 (gushing-type bleeding). They were seen every month for 3 months, then every 3 months for 9 months, and then every 6 months for 4 years for Papanicolau smear, pelvic examination, and transvaginal ultrasonography. They were asked to bring their diary of menstrual bleeding. They were asked about side effects and their satisfaction with the therapy. Peripheral blood was drawn for blood count and serum chemistries. Hysteroscopic-directed biopsies were repeated after 3 months of therapy in women with endometrial hyperplasia. The severity of blood loss was significantly reduced in all women after 3 months of treatment. All women with endometrial hyperplasia had regression of hyperplastic endometrium. None of the women with endometrial polyps had sonographic signs of recurrence during therapy. Only 10 women (50%) completed 1-year follow-up, and only 5 women (25%) completed 5-year follow-up. CONCLUSION: These results suggest that long-term administration of vaginal danazol after curettage or hysteroscopic-directed biopsy is both efficacious and safe in women with heavy menstrual bleeding, but the rate of discontinuance is high.  相似文献   
99.
100.
Puerperal hematomas are a major complication of delivery. Little information about the role of sonography in the management of puerperal hematomas is available in the English literature. We report a case of a vulvovaginal hematoma that developed subsequent to vaginal delivery and that was managed conservatively using sonography. Our report includes the sonographic follow-up of the lesion with MRI correlation. The present case report suggests that sonography has a role in the detection and follow-up of the condition, with MRI providing a more detailed mapping of the lesion and excluding any retroperitoneal involvement.  相似文献   
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