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41.

Background  

Both violence and depression during pregnancy have been linked to adverse neonatal outcomes, particularly low birth weight. The aim of this study was to investigate the independent and interactive effects of these maternal exposures upon neonatal outcomes among pregnant adolescents in a disadvantaged population from Sao Paulo, Brazil.  相似文献   
42.
Nitric oxide (NO) has been shown to play an important role in the pathophysiology of traumatic brain injury (TBI) and cerebral ischemia. However, its contribution to the pathogenesis of traumatic spinal cord injury (SCI) remains to be clarified. This study determined the time course of constitutive and inducible nitric oxide synthases (cNOS and iNOS, respectively) after SCI. Rats underwent moderate SCI at T10 using the NYU impactor device and were allowed to survive for 3, 6, or 24 h and 3 days after SCI (n = 5 in each group). For the determination of enzymatic activities, spinal cords were dissected into five segments, including levels rostral and caudal (remote) to the injury site. Other rats were perfusion fixed for the immunohistochemical localization of iNOS protein levels. cNOS activity was significantly decreased at 3 and 6 h within the traumatized T10 segment and at 3, 6, and 24 h at the rostral (T9) level (p < 0.05). Rostral (T8) and caudal (T11, T12) to the injury site cNOS activity was also decreased at 3 h after injury (p < 0.05). However, cNOS activity returned to control levels within 6 h at T8, T11 and T12 and at one day at T10 and T9 segments. iNOS enzymatic activity was elevated at all time points tested (p < 0.05), with the most robust increase observed at 24 h. Immunostaining for iNOS at 24 h revealed that a significant cellular source of iNOS protein appeared to be invading polymorphonuclear leukocytes (PMNLs). To assess the functional consequences of iNOS inhibition, aminoguanidine treatment was initiated 5 min after SCI and rats tested using the BBB open field locomotor score. Treated rats demonstrated significantly improved hindlimb function up to 7 weeks after SCI. Histopathological analysis of contusion volume showed that aminoguanidine treatment decreased lesion volume by 37% (p < 0.05). In conclusion, these results indicate that (1) cNOS and iNOS activities are regionally and temporally affected after moderate SCI, (2) the early accumulation of PMNLs are a potentially significant source of NO-induced cytotoxic products, and (3) acute aminoguanidine treatment significantly improves functional and histopathological outcome after SCI.  相似文献   
43.
PURPOSE: To report the efficacy of primary retrobulbar chlorpromazine injections for the management of blind and seeing painful eyes. PATIENTS AND METHODS: Retrospective case series from three university hospitals was done. Twenty eyes of 20 patients with at least 3 months of follow-up are reported. Ten of these 20 eyes did not receive any other ophthalmic medications either 2 weeks before chlorpromazine injection or at any time point after injection. Treatment was considered successful if pain control lasted for at least 3 months, without the need for reinjection or enucleation. RESULTS: Sixteen of 20 (80.0%) eyes achieved successful pain control. There were no permanent complications in any patient. CONCLUSIONS: Retrobulbar chlorpromazine appears to be safe and effective for the management of pain in blind eyes.  相似文献   
44.
The contribution of nitric oxide (NO) to articular pain in arthritis induced by zymosan (1 mg, intra articular) in rats was assessed by measuring articular incapacitation (AI). Systemic treatment with the non-selective NO synthase (NOS) inhibitor L-NAME (10 - 100 mg kg(-1) i.p.) or with the selective iNOS inhibitors aminoguanidine (AG; 10 - 100 mg kg(-1) i.p.) or 1400W (0.5 - 1 mg kg(-1) s.c.) inhibited the AI induced by injection of zymosan 30 min later. Local (intra articular) treatment with the NOS inhibitors (L-NAME or AG, 0.1 - 1 micromol; 1400W, 0.01 (micromol) 30 min before zymosan also inhibited the AI. Systemic or local treatment with the NOS inhibitors (L-NAME; AG, 100 mg kg(-1) i.p. or 0.1 micromol joint(-1); 1400W, 1 mg kg(-1) s.c. or 0.01 micromol joint(-1)), 2 h after zymosan did not affect the subsequent AI. Local treatment with the NO donors SNP or SIN-1, 2 h after zymosan did inhibit AI. L-NAME and AG, given i.p. inhibited nitrite but not prostaglandin E(2) (PGE(2)) levels in the joints. L-NAME (100 mg kg(-1)) but not AG (100 mg kg(-1)) increased mean arterial blood pressure. Neither L-NAME, AG nor the NO donor SIN-1 altered articular oedema induced by zymosan. In conclusion, inhibitors of iNOS decrease pain in zymosan arthritis only when given before the zymosan. This was not due to inhibition of articular PGE(2) release or oedema. NO donors also promoted antinociception in zymosan arthritis without affecting oedema.  相似文献   
45.
46.
The Brazilian dental care sector is facing a paradoxical crisis characterized by a surplus of dentists and a large contingent of people lacking dental care, thus highlighting the need to improve management strategies. One necessary step is to analyze the various payment schemes for dental services. This paper reviews two important approaches, fee for service and capitation, and considers the impacts and consequences of payment strategies on the dental care system.  相似文献   
47.
PURPOSE: Pressor responses are reflexly evoked by the activation of groups III and IV muscle afferents, which are also known to mediate nociceptive responses. In this experiment, the effects of analgesic balm (AB) application on these responses were investigated without the interference of other types of anesthesia or effects from the higher brain. METHODS: Heart rate (HR), blood pressure, and end-tidal CO(2) were monitored in midcollicularly decerebrated cats. Static contractions (30 s) of hindlimb muscles were evoked by electric stimulation of L7 and S1 ventral roots. After control runs, a commercial AB (1% capsaicin, 12.5% methyl salicylate) was applied to the skin surface over the contracting muscles. Muscle contractions were evoked every 10 min, alternating between the two hindlimbs. RESULTS: Changes in mean arterial pressure (MAP) evoked by static ipsilateral muscular contraction were significantly attenuated 20 min and 40 min after AB application. The decreases in the pressor response were significant at both the initial and the last parts of the stimulus intervention after 20 min of AB application. There were no significant changes in the response to contraction of the hindlimb contralateral to the AB application. Application of AB to the contralateral leg did not add to the ipsilateral effects. CONCLUSIONS: AB application to the skin surface over contracting muscles significantly decreased autonomic responses to static muscular contraction. This effect was independent of higher cortical processing and strongly suggests that application of methyl salicylate and capsaicin on the skin has analgesic effects on signals from receptors located in muscle.  相似文献   
48.
In recent decades there has been an increase in the occurrence of dental root surface caries, especially among adults and senior citizens. This study aimed to identify root surface caries prevalence in adults and seniors from southeast S?o Paulo State, Brazil. An epidemiological survey was carried out among 1,475 dentate adults, ages 35 to 44 and 65 to 74, respectively, according to WHO criteria. Root surface caries prevalence was 15.6% and 31.8%, for the 35-44 and 65-74-year groups, respectively. The average rate for decayed and/or filled roots was 0.36 for the middle-aged adult group and higher in males (p < 0.01), as compared to 0.82 for seniors, with no difference by gender. The average rate of decayed roots was 0.18 and 0.53 for middle-aged adults and seniors, respectively; in both groups the levels were higher among men (p < 0.01). Further studies on oral health, mainly on root surface conditions, are essential in both middle-aged adults and senior citizens.  相似文献   
49.
50.
OBJECTIVE: The objective of this study was to describe the role of pre- and postoperative dynamic CT in patients undergoing tracheoplasty, a novel surgical method for treatment of severely symptomatic tracheobronchomalacia. CONCLUSION: Five patients were referred for dynamic MDCT before and after undergoing tracheoplasty at our institution. Preoperatively, all patients showed signs of tracheobronchomalacia (> or = 50% airway collapse) on bronchoscopy, and four (80%) of these five patients showed evidence of malacia on dynamic forceful expiratory CT scans. In all five cases, postoperative CT showed a reduction in the degree of airway collapse during expiration, changes in shape of the trachea during inspiration, and posterior wall thickening related to the procedure. Our preliminary results suggest a potentially important role for CT in the pre- and postoperative assessments of patients with tracheobronchomalacia referred for tracheoplasty.  相似文献   
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