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51.

Objectives

We analyzed bladder calcifications occurring after photodynamic therapy administered for the treatment of superficial bladder cancer, a finding not previously reported after this treatment.

Methods

Bladder biopsies from 20 patients undergoing photodynamic therapy were evaluated. Bladder calcifications were identified in 2 patients and analyzed for composition.

Results

One patient had diffuse microcrystalline deposition in two biopsies composed of calcium oxalate monohydrate A. A second patient had a focal stone at a healing biopsy site composed of monoclinic calcium hydrogen phosphate dihydrate (brushite) (66%), calcium oxalate (25%), hydroxyapatite (6%), and protein (3%).

Conclusions

Rare calcium oxalate and brushite calcifications were identified after photodynamic therapy and presumed to occur because of tissue injury associated with treatment.  相似文献   
52.
Transplantations represent an important element of treatment in end-stage chronic disease both inborn (mostly genetic) and acquired (degenerative, neoplastic). They are supposed to establish durable coexistence of cells with different genetic origin (in most cases). This union is contradictory to immunological properties of the tissues involved and can only succeed in case of sufficient histocompatibility to be identified by the diagnostic tests of immunogenetics. This review discusses the current approach used in choosing the most appropriate donor for an individual patient, and in monitoring the maintenance of "chimerism" established by the transplantation focussing on bone marrow transplantation. Initially a general outline of indications for organ transplantation is given with emphasis laid on genetic disorders as the outlook of conservative treatments in inborn diseases is generally very poor.  相似文献   
53.
Summary The records of all testicular cancer patients evaluated and treated at our medical center during two consecutive 9-year periods were reviewed and analyzed for prognostic factors, particularly the impact of cisplatin-based combination chemotherapy. The data base of 244 patients was divided into two eras: 1970–1978, defined as the pre-cisplatin era (n=101) and 1979–1987, the cisplatin era (n=143). Statistically improved survival (P=0.024) was noted for the 165 nonseminoma patients and for a grouping of 143 patients treated with combination chemotherapy (P=0.004) during the cisplatin era. Stratification by stage revealed that stage II patients had the most significant survival advantage (P=0.001) during the cisplatin era; cancer mortality improved from 48% to 9%. Cancer death rates for stage III patients decreased from 58% to 39% which is clinically but not statistically significant (P=0.497). Stage I patients and the seminoma population did well during both eras, and the impact of cisplatin could not be statistically confirmed in this study for these subgroups. Multivariate statistical analysis confirmed the importance of the era of treatment for the nonseminoma population.  相似文献   
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Hambrecht R  Gielen S  Linke A  Fiehn E  Yu J  Walther C  Schoene N  Schuler G 《JAMA》2000,283(23):3095-3101
CONTEXT: Exercise training in patients with chronic heart failure improves work capacity by enhancing endothelial function and skeletal muscle aerobic metabolism, but effects on central hemodynamic function are not well established. OBJECTIVE: To evaluate the effects of exercise training on left ventricular (LV) function and hemodynamic response to exercise in patients with stable chronic heart failure. DESIGN: Prospective randomized trial conducted in 1994-1999. SETTING: University department of cardiology/outpatient clinic in Germany. PATIENTS: Consecutive sample of 73 men aged 70 years or younger with chronic heart failure (with LV ejection fraction of approximately 0.27). INTERVENTION: Patients were randomly assigned to 2 weeks of in-hospital ergometer exercise for 10 minutes 4 to 6 times per day, followed by 6 months of home-based ergometer exercise training for 20 minutes per day at 70% of peak oxygen uptake (n=36) or to no intervention (control group; n=37). MAIN OUTCOME MEASURES: Ergospirometry with measurement of central hemodynamics by thermodilution at rest and during exercise; echocardiographic determination of LV diameters and volumes, at baseline and 6-month follow-up, for the exercise training vs control groups. RESULTS: After 6 months, patients in the exercise training group had statistically significant improvements compared with controls in New York Heart Association functional class, maximal ventilation, exercise time, and exercise capacity as well as decreased resting heart rate and increased stroke volume at rest. In the exercise training group, an increase from baseline to 6-month follow-up was observed in mean (SD) resting LV ejection fraction (0.30 [0.08] vs 0.35 [0.09]; P=.003). Mean (SD) total peripheral resistance (TPR) during peak exercise was reduced by 157 (306) dyne/s/cm(-5) in the exercise training group vs an increase of 43 (148) dyne/s/cm(-5) in the control group (P=.003), with a concomitant increase in mean (SD) stroke volume of 14 (22) mL vs 1 (19) mL in the control group (P=.03). There was a small but significant reduction in mean (SD) LV end diastolic diameter of 4 (6) mm vs an increase of 1 (4) mm in the control group (P<.001). Changes from baseline in resting TPR for both groups were correlated with changes in stroke volume (r=-0.76; P<.001) and in LV end diastolic diameter (r=0.45; P<.001). CONCLUSIONS: In patients with stable chronic heart failure, exercise training is associated with reduction of peripheral resistance and results in small but significant improvements in stroke volume and reduction in cardiomegaly. JAMA. 2000.  相似文献   
58.
A possible cause of preterm labour is an increased synthesis of prostaglandins by a phospholipase A2 (PLA2) activity. PLA2 activity has been detected in Mycoplasma hominis. The aim of this study was to test whether chromosomal DNA of M. hominis contains sequences coding for PLA2. M. hominis was cultured in specimens from 5 women with normal pregnancy and 4 in preterm labour. Using sequence alignment, primer pairs for the active part of PLA2 of different species were designed for PCR analysis. No sequences coding for PLA2 could be amplified. Whatever its role in preterm labour, M. hominis is not involved in causing an increase of prostaglandin synthesis. Received: 21 September 1997 / Accepted: 17 January 1998  相似文献   
59.
BACKGROUND: The intestinal mucosa is the portion of the gut most susceptible to impaired perfusion and oxygen delivery. The phosphodiesterase (PDE) inhibitor amrinone has been proposed to improve oxygen delivery and tissue perfusion during sepsis. The objective of this study was to investigate the effects of amrinone on arterial oxygenation (Pao(2)) and tissue oxygenation (Ptio(2)) of jejunal mucosa during endotoxemia. MATERIALS AND METHODS: Forty anesthetized and ventilated rats were laparotomized and a jejunal portion was exteriorized and fixed on a plexiglass stage. The jejunum was punctured and a Clark-type microcatheter Po(2) probe and a microthermocouple were placed on the mucosa to measure Ptio(2). The animals were randomly assigned to receive one of the four treatments: infusion of Escherichia coli lipopolysaccharides (LPS, 2 mg/kg/h) without amrinone pretreatment (LPS group); infusion of LPS with amrinone pretreatment (40 microg/kg/min, start 30 min before LPS infusion, amrinone + LPS group); no treatment with either amrinone or LPS (control group); treatment with amrinone without LPS infusion (amrinone group). Mean arterial pressure (MAP), heart rate (HR), Pao(2), and Ptio(2) were measured 30 min before and 0, 60, and 120 min after induction of endotoxemia. RESULTS: MAP remained stable in the control and LPS groups. In the amrinone + LPS group MAP decreased within the first 30 min of amrinone infusion and decreased further during endotoxemia. Pao(2) remained stable in the control group and decreased in the LPS group. This endotoxin-induced decrease in Pao(2) was attenuated in the amrinone + LPS group. The mucosal Ptio(2) decreased in the LPS group but remained stable in both the control and amrinone + LPS groups. CONCLUSIONS: Pretreatment with amrinone was able to diminish a decrease in Pao(2) during endotoxemia, indicating that pulmonary dysfunction was attenuated. Endotoxin-induced tissue hypoxia of the intestinal mucosa, however, could be fully prevented, indicating that an additional improvement in compromised tissue perfusion had occurred.  相似文献   
60.
BACKGROUND: To assess the effects of treatment with nebulized corticosteroids immediately after chlorine gas injury. METHODS: Eighteen anesthetized and mechanically ventilated pigs were exposed to chlorine gas (140 ppm for 10 minutes) and observed for 6 hours. Nine pigs were treated with nebulized beclomethasone-dipropionate 20 microg/kg (BDP group), and nine pigs were given no treatment (control group). RESULTS: All animals developed severe pulmonary dysfunction. The initial decrease in PaO2 was similar in both groups, but BDP-treated animals improved whereas control animals deteriorated (p < 0.005; analysis of variance). Pulmonary vascular resistance increased in both groups but less in the BDP group (p < 0.01). Lung-thorax compliance was better preserved in the BDP group (p < 0.01), and oxygen delivery was significantly better in the BDP group (p < 0.01). One animal died in the BDP group, as did three animals in the control group. CONCLUSION: Immediate treatment with nebulized BDP improved pulmonary and cardiovascular function after experimental chlorine gas injury.  相似文献   
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