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971.
Role of nitric oxide in the rat hippocampal CA1 area on morphine-induced conditioned place preference 总被引:4,自引:0,他引:4
Effects of intrahippocampal CA1 injections of L-arginine, a nitric oxide (NO) precursor, and N(G)-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor, on morphine-induced conditioned place preference in male Wistar rats were investigated. Animals received subcutaneous (s.c.) injections of saline (1.0 ml/kg) or morphine (0.5-7.5 mg/kg) once daily for 3 days to induce conditioned place preference. The administration of L-arginine (0.3, 1.0, and 3.0 microg/rat), but not L-NAME (0.3, 1.0, and 3.0, microg/rat), prior to administration of morphine (5.0 mg/kg) during acquisition of morphine-induced conditioned place preference increased morphine-induced conditioned place preference, but the interaction between the response to morphine and/or L-arginine was not statistically significant. The response to L-arginine was blocked by L-NAME pre-administration. L-Arginine or L-NAME by itself did not induce conditioned place preference. The administration of L-arginine but not L-NAME, 1 min before conditioned place preference testing, increased the expression of morphine-induced conditioned place preference. Pre-administration of L-NAME blocked the L-arginine response. It is concluded that NO in the rat hippocampal CA1 area may be involved in morphine-induced conditioned place preference. 相似文献
972.
Influence of nitric oxide on morphine-induced conditioned place preference in the rat central amygdala 总被引:4,自引:0,他引:4
Effects of intra-central amygdala injections of L-arginine, a nitric oxide (NO) precursor, and N(G)-nitro-L-arginine methyl ester (L-NAME), a NO synthase (NOS) inhibitor, on morphine-induced conditioned place preference in rats were investigated by using an unbiased 3-day schedule of place conditioning design. Animals receiving once daily injections of morphine (0.5-7.5 mg/kg, subcutaneously, s.c.) or saline (1.0 ml/kg, s.c.) showed a significant place preference in a dose-dependent manner. The maximum response was observed with 5.0 mg/kg of the opioid. Co-administration of morphine (5.0 mg/kg) with L-arginine (0.3, 1.0 and 3.0 microg/rat), but not with L-NAME (0.3, 1.0 and 3.0 microg/rat), during the acquisition of morphine-induced conditioned place preference increased morphine-induced conditioned place preference. The response to L-arginine was blocked by L-NAME preadministration. L-arginine and L-NAME by themselves did not induce conditioned place preference. When L-arginine or L-NAME at 0.3-3.0 microg/rat was administered 1 min before conditioned place preference testing, L-arginine but not L-NAME caused an increase in the expression of morphine-induced conditioned place preference, the effect that was blocked by L-NAME preadministration. A dose of L-arginine (0.3 microg/rat), but not L-NAME, during expression of morphine-induced conditioned place preference produced an increase in locomotion compared with that in the control group. It may be concluded that an increase in the NO levels in the central amygdala may have an effect on the acquisition and expression of morphine-induced conditioned place preference. 相似文献
973.
Athar MN Baqai HZ Ahmad M Khalid MA Bashir N Ahmad AM Balouch AH Bashir K 《The American journal of tropical medicine and hygiene》2003,69(3):284-287
A nosocomial outbreak of Crimean-Congo hemorrhagic fever occurred in Rawalpindi, Pakistan in February 2002. The identified index case died shortly after admission to a hospital. Two of the health care workers became secondary cases; one of them died on day 13 after coming in contact with the index case. The other secondary case was successfully treated with oral ribavirin. 相似文献
974.
Omrani A Fathollahi Y Almasi M Semnanian S Mohammad S Firoozabadi P 《Brain research》2003,959(1):173-181
The role of ionotropic glutamate receptors and voltage-dependent calcium channels (VDCCs) in potentiation phenomenon and epileptic activity induced by a transient pentylenetetrazol (PTZ) application in the CA1 region of rat hippocampal slices was investigated. Also we examined whether adenosine as an inhibitory neuromodulator would interact with expression of the long-lasting effect of transient PTZ. Population spikes (PS) were recorded in the CA1 cell body layer of the hippocampal slices following stratum radiatum stimulation. Changes in the PS amplitude potentiation and number of extra PS, which induced by transient PTZ were used as indices to quantify the effects of drugs. PS input-output curve was significantly increased 10 min after PTZ application and persisted at least for 60 min after PTZ washout. Polyspikes also appeared, but did not persist. Both ketamine and APV reduced the extent of potentiation of PS amplitude but had no effect on number of extra PS. The selective non-NMDA receptor antagonist CNQX prevented the amplitude potentiation and the generation of extra PS. The blocker of VDCCs, verapamil, prevented the amplitude potentiation and inhibited polyspike activity. Co-application of adenosine and PTZ produced a rapid and reversible decrease in the PS amplitude, but PTZ-induced potentiation phenomenon was observed after washout. It is concluded that ionotropic glutamate receptors as well as VDCCs involve in the PTZ-induced LTP of PS amplitude. PTZ-induced LTP is also insensitive to adenosine. The epileptiform activity induced by a transient PTZ application could be attributed to VDCCs. The polyspikes mediated by VDCCs are dependent on prior activation of AMPA receptors. 相似文献
975.
PURPOSE: This study was designed to investigate the effect of epilepsy and antiepileptic drugs (AEDs) on both the physical and hormonal aspects of the sexual development of male patients with epilepsy. METHODS: One hundred thirty male subjects with epilepsy, their age ranging between 8 and 18 years (mean, 14 +/- 2.9 years), entered the study; all were taking AEDs. Anthropometric measurements [height, weight, and body mass index (BMI)], testicular volume, penile length, and pubarche were assessed in the studied groups, as well as measurement of the levels of testosterone (T), free testosterone (FT), estradiol (E2), lutenizing hormone (LH), follicle-stimulating hormone (FSH), and prolactin (PRL), and the results were compared with those of a control group. RESULTS: In this study, male patients older than 16 years were significantly shorter than their matched controls. The mean values of testicular volume and penile length were significantly lower in the patients in the different age subgroups, and the pubic hair staging (pubarche) was delayed in the patients older than 16 years. The mean values of total testosterone, estradiol, LH, and FSH serum levels were significantly higher, whereas the mean values of free testosterone, total-T/E2, total. T/LH, and FT/E2 ratios were lower in the patient subgroups compared with their age-matched controls. There were no significant changes in the mean basal PRL serum levels in the patients compared with the controls. The present study demonstrated a reduction in the testicular volume and penile length, significantly lower mean values of free testosterone and total-T/E2, and a higher mean value of E2 in the patients receiving polytherapy in the age subgroup older than 16 years compared with those on monotherapy; however, there was no demonstrable effect of seizure control or the duration of illness in any of the studied parameters. CONCLUSIONS: There is a delay in the sexual development of male patients with epilepsy in the different age subgroups, with endocrine changes in the form of increase in the total testosterone, but the free testosterone is lower, and an increase in estradiol, with lower T/LH levels. Patients receiving polytherapy, especially those older than 16 years, were more likely to have delayed gonadarch and disturbances in their hormonal profile. 相似文献
976.
Chemotherapy-induced acral erythema (CIAE), a toxic reaction to a number of different chomotherapeutic agents, causes a symmetrical, painful erythema of both the palms and soles which is self-limiting. The association of this syndrome with methotrexate is unusual; only nine cases have been reported in the literature. We describe the tenth case of this syndrome associated with methotrexate, which is also the third case of the bullous variant of methotrexate-induced acral erythema. Our case is unusual in that the acral erythema was present only on the soles of the feet and in that it was associated with the presence of diffuse maculopapular lesions over the legs and trunk. 相似文献
977.
Changes in plaque fluoride levels by school-based fluoride rinsing and tablet programs in Bangladesh
The aim of this study was to evaluate the effects of school-based fluoride rinsing and tablet programs on plaque fluoride levels. A total of 42 children (8-9 years) were selected from two neighboring schools in Dhaka, Bangladesh. After caries recordings, vestibular plaque samples from the maxillary central incisors and mandibular first molars were collected and frozen on day 0 (baseline). The subjects of one school (rinsing group, n = 15) rinsed with 0.05% NaF, while those from the other school (tablet group, n = 16) used a 0.5 mg F tablet on the 5 school days during a 3-week period. The surfaces were sampled on the first and last school day every week. The fluoride and protein contents of each sample were analyzed using micro-techniques. The median plaque fluoride levels were 9.1 ppm at baseline in the rinsing group and 2.5 ppm in the tablet group (P < 0.05). This difference could in part be related to reported fluoride toothpaste usage. After 4 days on the fluoride programs, plaque fluoride levels in the rinsing group increased to 27.3, 24.5 and 14.2 ppm in the 3 consecutive weeks. The corresponding values after tablet usage were 8.0, 6.5 and 7.1 ppm, respectively. After 3 days without fluoride during the weekends, levels declined towards baseline values in both groups. Hence, the plaque fluoride levels in 8 to 9-year-old Bangladeshi children were increased by both rinsing and tablet programs, but the effect was not detectable 3 days later. 相似文献
978.
Histopathologic comparison of normal and hyperplastic condyles 总被引:1,自引:0,他引:1
Eslami B Behnia H Javadi H Khiabani KS Saffar AS 《Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics》2003,96(6):711-717
OBJECTIVE: The aim of this study was to compare normal and hyperplastic mandibular condyles using two different histopathologic staining techniques. STUDY DESIGN: Nine cases of condylar hyperplasia and 13 normal cases were studied after hematoxylin and eosin and silver staining. RESULTS: There was a significant difference between the two groups in the thickness of the hyperplastic cartilage layer of condylar soft tissue (P = 0.017). Also, the number of argyrophilic nucleolar organizer regions was significantly higher in the condylar hyperplasia case group (P = 0.0001). No significant differences could be demonstrated in cartilage island frequency, penetration depth, and distribution in the cancellous bone of condyles. CONCLUSION: The thickness of the hyperplastic cartilage layer appears significantly increased in condylar hyperplasia. In addition, argyrophilic nucleolar organizer region count may be useful in histopathological identification of condylar hyperplasia. 相似文献
979.
Kamel HK Iqbal MA Mogallapu R Maas D Hoffmann RG 《The journals of gerontology. Series A, Biological sciences and medical sciences》2003,58(11):1042-1045
OBJECTIVE: To test the hypothesis: Time to ambulation (walking) after hip fracture surgery impacts the frequency of postoperative complications and length of hospital stay. METHODS: A retrospective observational study of a cohort of all patients admitted to a university teaching hospital with a principal International Classification of Diseases-9 diagnosis of a hip fracture during 3 calendar years. RESULTS: A total of 131 participants were identified (68% were aged 65 years or older). Overall, the mean time to writing an order to ambulate a patient after a hip fracture surgery was 2 +/- 1.5 days. Time to ambulation after hip fracture surgery was significantly less in patients cared for on orthopedic surgery service compared to general surgery service (1.8 +/- 1 vs 2.5 +/- 2, p <.05) or general internal medicine service (2.5 +/- 1.5, p <.05). It did not relate, however, to patient's age, sex, or race, or to patient's functional status prior to admission, fracture site (femoral neck, intertrochanteric, or subtrochanteric), whether a femoral neck fracture is displaced or not, type of anesthesia (spinal/epidural vs general), type of surgery (open reduction and internal fixation vs hemiarthroplasty), degree of preoperative risk, number of medical conditions, or to obtaining physical therapy and/or medical consultation. Time to ambulation after surgery was an independent predictor for the development of pneumonia (1.5 OR [odds ratio]/day, p <.001), new onset delirium (1.7 OR/day, p <.001), and to prolonged length of hospital stay (B [slope coefficient] = 1.36, p <.0001) but not to the development of pressure ulcers, deep venous thrombosis, or urinary tract infection. CONCLUSIONS: Delayed ambulation after hip fracture surgery is related to the development of new onset delirium and pneumonia postoperatively as well as to increased length of hospital stay. Early ambulation after hip fracture surgery should be encouraged. 相似文献
980.
Jazieh AR Kyasa MJ Sethuraman G Howington J 《The Journal of thoracic and cardiovascular surgery》2002,123(6):1173-1176
OBJECTIVES: The aim of our study was to identify the factors that determined whether a patient underwent surgery and its impact on patient outcome. METHODS: A retrospective evaluation of the records of all patients diagnosed with resectable stages I and II non-small cell lung cancer between 1990 and 1998 at the University of Arkansas and Veterans Administration Hospitals were included in the study. Demographic, clinical, pathologic, and outcome data were captured. Analysis was conducted to identify prognostic factors as well as factors leading to surgical treatment disparities. RESULTS: A total of 551 patients were included; 490 (89%) were men, 480 (87%) were white, and 315 (57%) were aged >65 years. Median follow-up of these patients was 24 months (1-109 months). Surgery was performed on 455 patients (82.6%); 26 patients received nonsurgical treatment including chemotherapy, radiation therapy, or both, and 70 patients did not receive any type of treatment. A univariate analysis revealed that age, race, sex, and forced expiratory volume in the first second were significantly different between the surgery and no surgery groups. However, a multivariate analysis showed that age, forced expiratory volume in 1 second, and hemoglobin were significantly different between both groups. The median overall survival was 45.5 months (1-109 months) for the surgically treated patients compared with 12.0 months (1-86 months) for those who did not undergo surgery (P <.0001). CONCLUSION: Elderly patients with early-stage non-small cell lung cancer are less likely to undergo a potentially curative surgical resection. Racial and sex disparities may be due to other comorbidities. 相似文献