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941.
942.
943.
Two nitroxide spin labels (NSL) were compared for in vitro relaxivity and in normal rats for efficiency of urographic enhancement. One of the NSL, PCA, a pyrrolidinyl agent, was ionic and one, NAT, was a non-ionic pyrrolidinyl NSL with multiple hydroxyl substituents for water solubility. Using both NSLs the renal medulla and papilla were noted to show greater contrast enhancement than the cortex, with a maximum enhancing effect between 5 and 15 minutes. Using doses of 1.0 and 2.5 mmol/kg, more than 100 per cent increases in spin echo intensities above the baseline were observed. The lowest tested dose of 0.1 mmol/kg showed an easily detectable enhancing effect for NAT. The good contrast enhancing properties of NAT, considered together with its better acute tolerance, justifies further investigation of this non-ionic compound.  相似文献   
944.
From 1969 through 1977, 210 patients with Stage IB carcinoma of the uterine cervix were treated at University of Maryland Hospital. Fifty-six patients were treated by radical hysterectomy (S), 136 patients were treated by a full course of radiation therapy (RT) only and 18 patients received radiation treatment following radical surgery (S + RT). The 5-year determinate survival rates were almost the same in the S group and RT alone group (79% and 77%, respectively). The 5-year determinate survival rate in the S + RT group was 50%, which was statistical significantly lower than S alone or RT alone groups (P less than 0.05). Several prognostic factors were analyzed in the radiated patients: the size of the primary lesion, location of the lesion within the cervix, tumor grade, age of the patients at the time of diagnosis, and complete blood count nadir during the course of radiation treatment. The only factor found to influence the prognosis was the size of the primary tumor. The patients with smaller tumors had a better prognosis; the absolute and determinate 5-year survival rates were 80% and 82%, while the absolute and determinate survival rates in the large, fungating tumor replacing the entire cervix were 56% and 60%, respectively (P less than 0.001). The complication rate was 22% in the RT alone, 22% in the S + RT, and 25% in the S alone groups.  相似文献   
945.
Classical galactosaemia due to galactose-1-phosphate-uridyltransferase deficiency is an inherited metabolic disorder with an estimated incidence of 1:40,000 in the Caucasian population. In neonates the disease presents as hepatopathy with cerebral involvement. Without treatment classic galactosaemia leads to cataract, hepatic insufficiency and failure to thrive, and may finally be fatal. Treatment consists of a lactose-free diet. Despite early initiation of dietary treatment and long-term compliance, more than 80% of female patients develop hypergonadotropic hypogonadism. This paper aims to give practical recommendations for diagnosis and treatment of hypergonadotropic hypogonadism in patients with classical galactosaemia.  相似文献   
946.
Recurrence of posterior uveal melanoma after 60Co episcleral plaque therapy   总被引:3,自引:0,他引:3  
The authors analyzed the clinical and follow-up data on 277 selected patients with primary choroidal or ciliochoroidal melanoma who were treated with 60Co plaque radiotherapy between 1976 and 1982. Local recurrence of the irradiated melanoma developed in 39 (14%) patients during the follow-up interval. The 5-year tumor recurrence rate (Kaplan-Meier) was estimated to be 12%. Multivariate prognostic factor analysis (Cox proportional hazards modeling) identified the largest linear tumor dimension and proximity of the posterior margin of the tumor to the optic nerve head as predictors of recurrence. The 5-year survival rate of patients whose tumors recurred (58%) was significantly (log-rank test P = 0.0023) worse than that of patients whose tumor remained clinically controlled (82%).  相似文献   
947.
Sacral acupuncture was used for pain relief during labour in 30 pregnant Nigerian women. It produced clinically adequate analgesia in 19 women (63.3%). 6 women in this group (31.6%) reported that they had experienced no pain whatsoever throughout the period of labour and delivery (average duration - 8 hours). 11 women (36.7%) had no pain relief and required pethidine injection when sacral acupuncture proved ineffective. 24 women (80%), including 5 who did not obtain relief, indicated their wish to have sacral acupuncture during their next confinement. 2 women (6.7%) objected to needling, 3 considered acupuncture useless while another 2 did not believe in it. The patients' cardio-respiratory functions and uterine contractions were not adversely affected. There were no untoward effects on the mothers or their neonates. The procedure was technically simple, the equipment light and cheap. The needles did not interfere with nursing or obstetric manouvres. The procedure was however time consuming. The results were inconsistent and unpredictable. Despite these limitations, the simplicity, cheapness and absence of physiological complications associated with the procedure, make it a worthwhile medical armament for pain relief in the Nigerian environment, with limited resources and specialized manpower.  相似文献   
948.
Two hundred healthy, unpremedicated children, ages 1–10 years, scheduled for elective outpatient surgery were studied in order to examine the effect of minimizing preoperative fasting on perioperative blood glucose concentrations in paediatric patients. None of the patients ingested solids after midnight. On the day of surgery, the children were assigned to one of two groups. Group A children (n= 113) were not allowed any liquids for at least 6 h prior to surgery (NPO). Children in Group B (n= 87) ingested 10 ml·kg?1 of apple juice 2–4 h prior to the induction of anaesthesia. All patients received lactated Ringer's solution intraoperatively, unless BG at induction was < 50 mg·dl?1 (2.8 m·mol·l?1) in which case dextrose 2.5% in lactated Ringer's solution was administered. None of the patients who received apple juice was hypoglycaemic during induction of anaesthesia. However, two children in the NPO group had blood glucose values ± 50 mg·dl?1 (2.8 m·mol·l?1) at the time of induction of anaesthesia. Thirteen (11%) patients in Group A and 6 (7%) patients in Group B showed either no change or a further decrease in their postoperative BG concentration as compared with their induction values. Two of 43 patients in Group A and 2 of 41 patients in Group B had gastric fluid volumes > 0.4 ml/kg. All patients in both groups had gastric pH < 2.5. This study shows that gastric fluid volume and pH following a 2–4 h fast are not different from the values measured in children who were subjected to a traditional fasting period of 6 h or longer. Moreover, apple juice consumed 2–4 h prior to surgery neither buffers gastric pH nor does it modify intraoperative glucose homeostasis in children.  相似文献   
949.
A new technique for catheter ablation of atrioventricular (AV)conduction, using temperature-controlled radiofrequency energyand a bipolar asymmetrical electrode configuration, was appliedto 12 patients (mean age, 48 ± 15 years; range, 18–69years) with medically refractory atrioventricular nodal reentranttachycardia (AVNRT) or rapid atrial rhythms. The energy sourcewas a 500 kHz generator with automatic power regulation to apreselected temperature of 80 °C. A specially designed 7F bipolar asymmetric thermo-catheter was used for ablation inall cases. The endpoints of the procedure were: first-degreeAV block in patients with AVN R T and third-degree block inpatients with atrial fibrillation or flutter. Energy was appliedover a range of 1–14 times per patient. After a mean follow-upof 8±4 months, third- or first degree AV block persistedin eight patients. In comparison to constant-power radiofrequencyablation, where impedance rises are commonly observed, no impedancerise or coating of the electrode occurred during any of the97 energy applications in this study. Variable wall contactof the electrode was identified in 20 of 97 applications bya slow temperature rise or a drop in temperature and frequentpower adjustments. Thus, monitoring temperature and automaticpower regulation may help to reduce the total delivered energy.Temperature control during radiofrequency energy avoids coagulumformation and consequently the associated potential hazardsof constant-power application.  相似文献   
950.
Cytostatic as well as cytotoxic effects of tumour necrosis factor alpha (TNF-α) therapy have been shown in vitro and in experimental in vivo models. Nevertheless, the mechanism of anti-tumour activity in humans in vivo remains unclear. To determine the role of the vascular lining endothelial cells as important mediators of several immunological interactions, we investigated changes in the levels of the soluble endothelial cell adhesion molecules intercellular adhesion molecule 1, E-selectin and vascular cell adhesion molecule 1 as well as of soluble TNF receptors I and II during systemic therapy with recombinant human rhTNF-α (rhTNF-α). All tests were performed by enzyme-linked immunosorbent assays (ELISAs). The clinical efficacy of the intravenous rhTNF-α therapy was poor. Only one patient with isolated intra-arterial limb perfusion had a delayed, marked, but only temporary necrosis of tumour cells. In contrast, we found a marked, significant and (during therapy) undulating augmented increase in the levels of soluble adhesion molecules as well as of the soluble TNF receptors. Taken together, these data support the hypothesis that a sufficient tumour-specific cellular immunity is required to achieve a clinically apparent efficacy of systemic rhTNF-α therapy in addition to cytokine-dependent inducible activation mechanisms. In this context, the vascular lining endothelial cells might play an important role as mediators of the complex immunological antitumoral activity.  相似文献   
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