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61.
62.
Human cerebral cortices adjacent to men-ingiomas were studied with an electron microscope and compared with the normal materials of adult rabbits. Various types of presynaptic degenerations are observed in the cerebral cortices adjacent to meningiomas. The glycogen granules appear diffusely in the perikaryal cytoplasm and the dendrites of the nerve cells adjacent to meningiomas, and they accumulate abundantly in the astrocytic cytoplasm and the processes adjacent to the tumors. In most endothelial cells of capillaries adjacent to the tumors, many pino-cytotic vesicles are observed. These degenerative alterations of the neuronal and glial components and reactive changes of the vascular walls adjacent to meningiomas might be due to the neoplastic process.  相似文献   
63.
We report on a 45-year-old patient with stage IIIc ovarian cancer, multiple brain metastases, and meningitis carcinomatosa. After three courses of initial chemotherapy, consisting of docetaxel and carboplatin, the patient underwent interval cytoreductive surgery, consisting of hyster-ectomy, bilateral salpingo-oophorectomy, omentectomy, appendectomy, and retroperitoneal lymphadenectomy. Then five courses of the same chemotherapy were given as adjuvant treatment. At the completion of the primary therapy, she achieved a complete remission. Ten months after the completion of the initial treatment, multiple brain metastases with meningitis carcinomatosa were detected. After four courses of the same chemotherapy, she again had a complete response, confirmed by cranial enhanced magnetic resonance imaging (MRI), and she felt well, with relief from the debilitating neurologic symptoms for 4 months. After this 4 months, her disease recurred, with meningitis carcinomatosa, and she requested supportive care only. She died 4 months after this recurrence. Chemotherapy can help to prolong life for some patients with multiple brain metastases and meningitis carcinomatosa from ovarian cancer.  相似文献   
64.
Rationale Recent studies have shown that endogenous opioid systems are associated with the regulation of emotional responses. In particular, it has been reported that δ-opioid receptors act naturally to inhibit stress and anxiety. Objective The present study was designed to examine the possible involvement of opioid δ-receptor subtypes in the anxiety-related behavior in the elevated-plus-maze test. Methods Six-week-old male Lewis rats were used. The total numbers of visits to the closed and open arms and the cumulative time spent and visits in the open arms were determined. Plasma corticosterone levels were measured by enzyme immunoassay. Results Naltrindole (NTI), a δ-opioid receptor antagonist (3 mg/kg s.c.), induced a significant decrease in the percentages of time spent and visits in the open arms. Naltriben (NTB), a δ2-opioid receptor antagonist (3 mg/kg s.c.), but not 7-benzylidenenaltrexone, a δ1-opioid receptor antagonist, produced similar anxiety-related behaviors in the elevated plus-maze. These effects of NTI and NTB were antagonized by pretreatment with (+)-4-[(aR)-a-((2S,5R)-4-allyl-2,5-dimethyl-1piperazinyl)-3-methoxybenzyl]-N,N-diethylbenzamide (SNC80), a δ-opioid receptor agonist. Furthermore, after exposure to the elevated plus-maze, the maximal increase in the plasma corticosterone level in NTI-treated rats was clearly higher than that in vehicle-treated rats. However, when NTI and SNC80 were coadministered, higher levels of plasma corticosterone were not seen after exposure to the elevated plus-maze. Conclusion These results suggest that endogenous δ2-opioid-receptor-mediated systems are involved in the regulation of anxiety-related behaviors and might play a physiologically important role in the regulation of adrenocortical activity.  相似文献   
65.
We previously reported that streptozotocin (STZ)-induced diabetic mice exhibited depressive-like behavior in the tail suspension test. In this study, we examined the involvement of benzodiazepine receptor functions in this diabetes-induced depressive-like behavior in mice. STZ-induced diabetes significantly increased the duration of immobility without affecting spontaneous locomotor activity. This increase was dose-dependently and significantly suppressed by a benzodiazepine receptor antagonist, flumazenil (0.1-1 mg/kg, i.v.). However, flumazenil (0.1-1 mg/kg, i.v.) did not affect the duration of immobility in non-diabetic mice. Furthermore, flumazenil (1 mg/kg, i.v.) had no significant effect on spontaneous locomotor activity in either non-diabetic or diabetic mice. The benzodiazepine receptor inverse agonist methyl beta-carboline-3-carboxylate (beta-CCM; 0.03-0.3 mg/kg, i.v.) dose-dependently and significantly increased the duration of immobility in non-diabetic mice, but not in diabetic mice. beta-CCM (0.3 mg/kg, i.v.) significantly suppressed spontaneous locomotor activity in non-diabetic mice, but not in diabetic mice. These results indicate that diabetic mice may have enhanced negative allosteric modulation by benzodiazepine receptor ligands, such as diazepam binding inhibitors, under stressful conditions, but not free-moving conditions, and this abnormal function of benzodiazepine receptors may cause, at least in part, the expression of depressive-like behavior in diabetic mice.  相似文献   
66.
With the evolving and diverse electronic medical record (EMR) systems, there appears to be an ever greater need to link EMR systems and patient accounting systems with a standardized data exchange format. To this end, the CLinical Accounting InforMation (CLAIM) data exchange standard was developed. CLAIM is subordinate to the Medical Markup Language (MML) standard, which allows the exchange of medical data among different medical institutions. CLAIM uses eXtensible Markup Language (XML) as a meta-language. The current version, 2.1, inherited the basic structure of MML 2.x and contains two modules including information related to registration, appointment, procedure and charging. CLAIM 2.1 was implemented successfully in Japan in 2001. Consequently, it was confirmed that CLAIM could be used as an effective data exchange format between EMR systems and patient accounting systems.  相似文献   
67.
Conclusions The present ESR study on the13C enriched carbonate apatites suggested that the doublet signal of 146 gauss disposed on either side of the asymmetric signal is a hyperfine splitting due to13C. The doublet signal of 170 gauss which has been observed in enamel samples by several workers is tentatively attributed to another hyperfine splitting due to13C.  相似文献   
68.
The long-term effects of the 77-kDa muscle-derived protein (MDP77) on motor and sensory nerve regeneration were examined in vivo. Fourteen-millimeter bridge grafts of the right sciatic nerve of SD rats were carried out with silicone tubes containing a solution of type I collagen together with 0, 5, 10, or 20 microg/ml recombinant human MDP77 (N = 10 in each group). Recovery of motor and sensory function was evaluated monthly by the maximal toe-spread index (TSI) and hot-plate test, respectively, for 6 months after the operation. Electrophysiology (nerve conduction velocity), histology (diameter and total number of the regenerated myelinated axons in the tube), and immunohistochemistry (total number of Schwann cells in the tube), as well as measurement of soleus muscle weight, were also performed at this time. Motor, but not sensory, function recovered rapidly in the MDP77-treated groups in a dose-dependent manner. Electrophysiological measurements and the ratio of soleus muscle weight corroborated the positive effects of MDP77 on motor nerve regeneration, but no facilitation of sensory nerve recovery was observed. Furthermore, histological and immunohistochemical evaluations suggested that MDP77 treatment accelerates Schwann cell migration, followed by enhanced maturation of regenerating axons, resulting in functional recovery of both the nerves and the atrophied, denervated muscle.  相似文献   
69.
The neural mechanisms of propofol-induced central respiratory depression remain poorly understood. In the present study, we studied these mechanisms and the involvement of gamma-aminobutyric acid (GABA)A receptors in propofol-induced central respiratory depression. The brainstem and the cervical spinal cord of 1- to 4-day-old rats were isolated, and preparations were maintained in vitro with oxygenated artificial cerebrospinal fluid. Rhythmic inspiratory burst activity was recorded from the C4 spinal ventral root. The activity of respiratory neurons in the ventrolateral medulla was recorded using a perforated patch-clamp technique. We found that bath-applied propofol decreased C4 inspiratory burst rate, which could be reversed by the administration of a GABAA antagonist, bicuculline. Propofol caused resting membrane potentials to hyperpolarize and suppressed the firing of action potentials in preinspiratory and expiratory neurons. In contrast, propofol had little effect on resting membrane potentials and action potential firing in inspiratory neurons. Our findings suggest that the depressive effects of propofol are, at least in part, mediated by the agonistic action of propofol on GABAA receptors. It is likely that the GABAA receptor-mediated hyperpolarization of preinspiratory neurons serves as the neuronal basis of propofol-induced respiratory depression in the newborn rat.  相似文献   
70.
AIM: To evaluate the efficacy of prednisolone, warfarin, and dipyridamole therapy combined with mizoribine (PWDM) in the treatment of diffuse immunoglobulin A (IgA) nephropathy in comparison with prednisolone, warfarin, and dipyridamole therapy without mizoribine (PWD) and with methylprednisolone pulse therapy (PWD pulse). METHODS: We collected data on 61 patients diagnosed with diffuse IgA nephropathy, and these patients were retrospectively divided into three groups without randomization. Group A included 21 patients before 1987 who were treated with PWD for 24 months, group B included 20 patients from 1987 to 1989 who were treated with PWD pulse therapy for 24 months, and group C included 20 patients after 1990 who were treated with PWDM for 24 months. Clinical features and pathological findings in each group were analyzed retrospectively. RESULTS: The time from initiation of therapy in group A, group B, and group C was 8.9 +/- 5.2, 8.1 +/- 3.9, and 7.7 +/- 3.8 years, respectively. At the latest follow-up examination, the mean urinary protein excretion (mg/m2/h) was 17 +/- 10 in group A, 22 +/- 20 in group B, and 6 +/- 6 in group C and had decreased significantly in group C as compared with the other groups. The activity index in all three groups was lower at the second biopsy than that at the first biopsy (5.1 +/- 0.8 vs. 6.5 +/- 2.1 in group A, p < 0.05; 5.6 +/- 0.9 vs. 6.6 +/- 1.7 in group B, p < 0.01, and 4.5 +/- 1.0 vs. 6.8 +/- 1.9 in group C, p < 0.01). The chronicity index in groups A and B at second biopsy was higher than at first biopsy (7.3 +/- 1.4 vs. 4.8 +/- 1.0 in group A, p < 0.01, and 8.1 +/- 2.0 vs. 5.3 +/- 0.9 in group B, p < 0.01), but was unchanged in group C. At the latest follow-up examination, 1 patient (4.8%) in group A, 3 patients (15%) in group B, and none (0%) in group C had renal insufficiency. CONCLUSION: These results suggest that PWDM appears to be more effective than PWD or PWD pulse in ameliorating proteinuria and histological severity of patients with IgA nephropathy.  相似文献   
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