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1.
Intratemporal vascular tumors: detection with CT and MR imaging   总被引:1,自引:0,他引:1  
The diagnostic contributions of computed tomography (CT) and magnetic resonance (MR) imaging were compared in 12 patients with benign intratemporal vascular tumors (hemangioma or vascular malformation). The tumors included six in the internal acoustic canal and six in the geniculate ganglion region. Clinical and histologic correlations were made. Two of the six patients with tumors in the internal acoustic canal underwent CT, and both required gas cisternography to show the tumor. Five patients in that group underwent MR imaging, and all five studies showed the tumor. All six patients with geniculate ganglion tumors underwent CT. Results in one study were questionable, and five showed the tumor. Five patients in this group underwent MR imaging, but the MR findings were positive in only two cases. MR imaging should therefore be performed before CT in the evaluation of facial nerve dysfunction, as it demonstrated all tumors in the internal acoustic canal and some in the geniculate ganglion region. If MR findings are negative, CT should then be performed to rule out a possible geniculate ganglion lesion.  相似文献   
2.
Thirty patients with progressive metastatic breast cancer and one prior chemotherapy regimen were treated with iproplatin at a starting dose of 300 mg/m2 iv every 3 weeks. After the first 11 patients, the starting dose was decreased to 270 mg/m2. There were one complete remission, three partial remissions, and two minor responses. Responses were observed in soft tissue and osseous and visceral areas. Grade 3 nausea and vomiting were observed in 38% of patients, and grade 3 diarrhea occurred in 31%. The dose-limiting toxicity was thrombocytopenia, which required dose de-escalation in 15 patients. No nephrotoxicity, neurotoxicity, or ototoxicity was observed. Iproplatin has modest antitumor activity in this group of previously treated patients with metastatic breast cancer.  相似文献   
3.
An analysis of the Coronary Artery Surgery Registry (CASS) was performed to determine the occurrence of stroke after coronary artery bypass surgery in patients entered into the Coronary Artery Surgery Study Registry. Of the 10,098 patients having coronary artery bypass surgery at the Coronary Artery Surgery Study participating sites during the period July 1974 through May 1979, a total of 348 patients (or 3.4%) sustained a stroke during the first year after coronary bypass surgery. Fifty-nine strokes occurred on the day of surgery, and an additional 129 strokes occurred during hospitalization for coronary bypass surgery. Thus, 188 patients (1.9%) of the entire surgical group sustained a stroke during initial hospitalization for coronary artery bypass surgery. Logistic regression analysis was used to predict stroke on the day of surgery, during the hospitalization for surgery, and during the first year after surgery. The most powerful predictors of stroke on the day of coronary artery bypass surgery were: 1) older age (n = less than 0.0001); 2) use of alpha-adrenergic drugs after bypass (n = 0.0001); and 3) longer duration of cardiopulmonary bypass (n = 0.002). For those strokes occurring at least 1 day after coronary artery bypass but during the initial hospitalization, age and duration of cardiopulmonary bypass were the most powerful predictors of stroke. An analysis of predictors of stroke within 1 yr after hospital dismissal for initial coronary bypass surgery revealed that the most powerful predictor was a history of previous cerebrovascular disease (n less than 0.0001) and a history of hypertension (n less than 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
4.
R E Vlietstra  R A Kronmal  A Oberman  R L Frye  T Killip 《JAMA》1986,255(8):1023-1027
Through a multicenter registry of patients in the Coronary Artery Surgery Study, we prospectively evaluated morbidity and mortality in 4,165 smokers with angiographically proved coronary artery disease, 2,675 of whom continued to smoke and 1,490 of whom quit. At five years, mortality (adjusted by Cox analysis for baseline differences) was 22% for those who continued smoking and 15% for quitters. The relative risk (also from the Cox analysis) for mortality in continuers vs quitters was 1.55 (95% confidence interval, 1.29 to 1.85). The adverse effect of smoking mainly took the form of higher frequencies of myocardial infarction--associated death and sudden death: the frequencies of these events during follow-up in continuers vs quitters were 7.9% vs 4.4% for myocardial infarction--associated death and 2.8% vs 1.5% for sudden death. This study supports the recommendation that patients with coronary artery disease should stop smoking.  相似文献   
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Thirty-five patients hospitalized for recent angiographically documented arterial occlusion in the legs (27 femoropopliteal arteries and eight grafts) benefited from local fibrinolytic therapy delivered at the site of the occlusion with a 4- or 5-F catheter. This therapy combined a continuous urokinase (UK) infusion of 1,000 U/kg/hour and a lysyl plasminogen (LYS-PLG) infusion of 15 microkatals every 30 minutes. Angiographically confirmed lysis was obtained in 85% of the cases. Only 3% of the patients had major and 6% had minor groin hematomas. Only two patients had concentrations of fibrinogen as low as 100 mg/dl. Intravascular infusion of UK-LYS-PLG is as effective as streptokinase. Its excellent tolerance makes it a good alternative in the treatment of acute ischemia in the lower limbs.  相似文献   
8.
Progestogenic stimulation of both the ventromedial nucleus of the hypothalamus (VMH) and the ventral tegmental area (VTA) is critical for normal receptivity in estrogen-primed hamsters. However, anatomical and biochemical studies have identified very few estrogen-induced progestin receptors in the rodent ventral midbrain. To determine whether progesterone might be working on the membrane of neurons in the VTA, progesterone 3-CMO BSA (P-3-BSA) was applied intracranially. The size of P-3-BSA makes it relatively impermeable to the cell membrane. Ovariectomized hamsters were implanted with 2 chronic cannulae, one aimed at the VMH and the other at the contralateral VTA. These animals were then estrogen-primed and tested for sexual receptivity after progesterone-containing tubes were inserted just dorsal to the VMH and P-3-BSA inserts were applied above the VTA. The following week, the hamsters were tested again with the contents of the inserts reversed. Animals with progestogenic stimulation to the VMH and P-3-BSA to the VTA were receptive yet those with P-3-BSA to the hypothalamus and progesterone to the VTA were not receptive. These data suggest that progesterone is capable of facilitating sexual receptivity within the VTA by actions on the cell membrane. The non-genomic effects in the VTA require concurrent genomic activation by progesterone within the hypothalamus.  相似文献   
9.
Progestogenic stimulation of both the ventral medial nucleus of the hypothalamus (VMH) and the ventral tegmental area (VTA) within the midbrain is critical for normal receptivity in female hamsters. However, few estrogen-induced progestin receptors have been found in the midbrain. In addition, recent evidence suggests that progestin's action in the VTA is mediated nongenomically at the membrane. The present experiment investigated the possible role of GABAA receptors in mediating the effects of progesterone in this brain region. Ovariectomized female hamsters were bilaterally implanted with chronic cannulae aimed toward the ventral mesencephalon. Five days after surgery, animals were injected with 10 micrograms estradiol benzoate SC. Forty hours later, the same animals were injected with either 25 or 100 micrograms progesterone and at hour 43.5, 50 ng muscimol was infused in 0.5 microliters. Control animals received 0.5 microliters vehicle, sterile saline, or no infusion. At hour 44, animals were tested for sexual receptivity by placing them in an observation arena with a sexually experienced male for 10 min, during which lordosis duration was recorded. The following week, the same regimen was given with the alternate dose of progesterone. Histology revealed that only those animals that were infused with muscimol into the VTA had total lordosis durations that were significantly longer than the controls. Implants that missed the ventral tegmental area were much less effective. These results indicate that GABA might play a facilitatory role in enhancing the efficacy of threshold doses of progesterone. Whether this interaction is due to a direct effect of progestins on the GABAA receptor complex awaits further study.  相似文献   
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