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151.
We report on a seven-year-old boy with inflammatory relapsing-remitting CNS disease, involving the optic nerves and spinal cord, with increasingly severe sequelae after each relapse. Clinical course, neuroimaging and laboratory findings were consistent with neuromyelitis optica. Biopsy of leptomeninges and underlying nervous tissue showed increased vascularization and thickened hyalinized vessel walls, reported as suggestive for neuromyelitis optica. Clinical features at onset were atypical, rendering the case highly unusual and the diagnosis tentative.  相似文献   
152.
Pre-eclampsia is an extremely severe condition. It is associated with vasospasm, activation of the coagulation system and abnormal haemostasis. In pre-eclamptic patients increased plasmatic concentrations of fibronectin, laminin, von Willebrand factor (VWF) and endothelin are observed. Experimental studies on rats have also shown that the doses of antithrombin III (AT) needed to mediate anti-inflammatory processes are much higher than those required to obtain the anti-coagulant effect. The study aimed to evaluate the clinical efficacy of treatment with high AT doses (HD) in comparison with standard doses (SD). The primary endpoint was the prolongation of pregnancy defined as time (in days) from enrollment to delivery and to assess the maternal bleeding at and after delivery. The secondary endpoint was to demonstrate a role for AT in controlling haemostasis at conventional doses, and the inflammatory state at higher doses. The biochemical parameters assessed were: AT activity (%), Fibronectin (Fn), Fibrinogen, D-dimer, Uricemia, Proteinuria 24h, Protein C Reactive (PCR), Granulocyte Elastase and Endothelin. This study included 23 pre-eclamptic women. Patients were randomly subdivided into two groups: 10 patients ("cases") were treated with high doses of AT (6 vials: 3000 units) once daily for 5 days, or until delivery, while 13 women ("controls") were treated with doses of AT sufficient to maintain at least 80% of the activity. High-dose therapy was associated with prolongation of pregnancy by 2.5 days more when compared with controls (p = 0.03; Mann-Whitney test). The incidence of clinical significant bleeding was lower in cases than in controls (mean 550 mL vs. 650 mL, respectively). Preventive- and conservative-type treatment of moderate-severe pre-eclampsia, based on the administration high doses of AT, allows a significant prolongation of pregnancy, and thus a better neonatal outcome, as well as less maternal intra- and post-operative bleeding. Fn, PCR and elastase levels (markers of inflammation) decrease in the HD group in comparison with SD group. In the HD group, the AT plasma levels were obviously higher both at the end of the treatment (p < 0.0001) and after delivery (p = 0.03), in comparison with SD group. The fibrinogen and D-dimer levels were above the reference interval in both groups. TPA and PAI 1 were found to be significantly raised in the course of pre-eclampsia. In conclusion, the bio-chemical findings support a role for AT in controlling the haemostasis at conventional doses, and the inflammatory state at higher doses.  相似文献   
153.
154.
The surgical indications for the treatment of unilateral hip dislocations or subluxations in patients with low lumbar myelomeningocele remain highly debatable. This study examines the influence of unilateral hip dislocation or subluxation on the gait of these patients using three-dimensional gait analysis. Twenty patients with a diagnosis of low lumbar myelomeningocele underwent three-dimensional gait analysis. All patients were community ambulators with solid ankle-foot orthoses and crutches who presented with unilateral hip dislocation or subluxation and no scoliosis. The patients were divided in two groups. Group 1 comprised 10 patients who demonstrated either no evidence of hip flexion or adduction contractures or symmetric hip contractures. Group 2 comprised 10 patients with unilateral hip flexion and/or adduction contractures. Pelvic and hip kinematics were assessed to determine the symmetry of motion between the involved and the noninvolved side during walking. Seven patients from group 1 walked with a symmetric gait pattern; only two patients from group 2 walked with a symmetric pattern. Gait symmetry corresponded to the absence of hip contractures or bilateral symmetrical hip contractures and had no relation to the presence of hip dislocation. The authors concluded that reduction of the hip is unnecessary.  相似文献   
155.
The relative sensitivity of four benthic invertebrates (Hyalella azteca, Chironomus riparius, Hexagenia spp., and Tubifex tubifex) was determined for Cd, Cu, and Ni in water-only and in spiked-sediment exposures. Survival (median lethal concentrations [LC50s] and the concentrations estimated to be lethal to 25% of test organisms [LC25s]), and endpoints for growth and reproduction (mean inhibitory concentrations [IC25s]) were compared. The sensitivities differed depending on the species and metal, although some trends emerged. In water-only exposures, H. azteca is the most sensitive species to cadmium and nickel, with mean LC50s of 0.013 and 3.6 mg/L, respectively; C. riparius is the most sensitive species to copper, with a mean LC50 of 0.043 mg/L. In the spiked-sediment exposures, the order in decreasing sensitivity to copper is Hyalella = Hexagenia < Chironomus < Tubifex for survival and growth/reproduction. For cadmium, the order in decreasing sensitivity is Hyalella = Chironomus < Hexagenia < Tubifex, and for nickel is Hyalella < Hexagenia < Chironomus < Tubifex. Chironomus riparius and Hexagenia spp. survival can be used to distinguish between toxicity caused by different metals. Species test responses in field-collected sediment(Collingwood Harbour, ON, Canada) were examined in an attempt to determine the causative agent of toxicity throughout, using the established species sensitivities. Sediment toxicity was categorized first by comparing species responses to those established for a reference database. Test responses in the field-collected sediment do not support causality by Cu, a suspected toxicant based on comparison of sediment chemistry with sediment quality guidelines.  相似文献   
156.
CONTEXT AND OBJECTIVE: Breast cancer screening programs are critical for early detection of breast cancer. Early detection is essential for diagnosing, treating and possibly curing breast cancer. Since there are no data on the incidence of breast cancer, nationally or regionally in Brazil, our aim was to assess women by means of mammography, to determine the prevalence of this disease. DESIGN AND SETTING: The study protocol was designed in collaboration between the Department of Diagnostic Imaging (DDI), Institute of Diagnostic Imaging (IDI) and S?o Paulo Municipal Health Program. METHODS: A total of 139,945 Brazilian women were assessed by means of mammography between April 2002 and September 2004. Using the American College of Radiology (ACR) criteria (Breast Imaging Reporting and Data System, BIRADS), the prevalence of suspected and highly suspected breast lesions were determined. RESULTS: The prevalence of suspected (BIRADS 4) and highly suspected (BIRADS 5) lesions increased with age, especially after the fourth decade. Accordingly, BIRADS 4 and BIRADS 5 lesions were more prevalent in the fourth, fifth, sixth and seventh decades. CONCLUSION: The presumed prevalence of suspected and highly suspected breast cancer lesions in the population of S?o Paulo was 0.6% and it is similar to the prevalence of breast cancer observed in other populations.  相似文献   
157.
Over 200 measurements of the resting rate of oxygen consumption using an open-circuit method were made on 15 small babies nursed in their usual clinical setting during the first month of life. There were striking and persistent variations between babies that could not be explained by postnatal age, relationship to feed, sleep, or time of day. It was not possible from clinical examination to predict which babies had the higher or lower metabolic rates, except that babies who were light-for-dates generally had higher values. Because of these variations the appropriate thermal temperature for small babies cannot be predicted from average values adjusted for body weight and postnatal age alone.  相似文献   
158.

Background and purpose:

5-Hydroxytryptamine (5-HT) is a key regulator of the gastrointestinal system and we have shown that submucosal neuronal 5-HT3 receptors exerted a novel inhibitory effect on colonic ion transport. The aim of the present study was to investigate the precise mechanism(s) underlying this inhibitory effect.

Experimental approach:

Mucosa/submucosa or mucosa-only preparations from rat distal colon were mounted in Ussing chambers for measurement of short-circuit current (Isc) as an indicator of ion secretion. Somatostatin release was determined with radioimmunoassay. Intracellular cAMP content was measured with enzyme-linked immunoadsorbent assay (elisa). Immunohistochemical techniques were used to study the expression of 5-HT3 receptors, somatostatin and somatostatin receptors in colonic tissue.

Key results:

In rat distal colonic mucosa/submucosa preparations, pretreatment with 5-HT3 receptor antagonists enhanced 5-HT-induced increases in Isc. However, in mucosa-only preparations without retained neural elements, pretreatment with 5-HT3 receptor antagonists inhibited 5-HT-induced ΔIsc. Pretreatment with a somatostatin-2 (sst2) receptor antagonist in mucosa/submucosa preparations augmented 5-HT-induced ΔIsc. Combination of sst2 and 5-HT3 receptor antagonists did not cause further enhancement of 5-HT-induced ΔIsc. Moreover, both sst2 and 5-HT3 receptor antagonists enhanced 5-HT-induced increase in intracellular cAMP concentration in the mucosa/submucosa preparations. 5-HT released somatostatin from rat colonic mucosa/submucosa preparations, an effect prevented by pretreatment with 5-HT3 receptor antagonists. Immunohistochemical staining demonstrated the presence of 5-HT3 receptors on submucosal somatostatin neurons and of sst2 receptors on colonic mucosa.

Conclusion and implications:

Activation of neuronal 5-HT3 receptors in the submucosal plexus of rat colon suppressed 5-HT-induced ion secretion by releasing somatostatin from submucosal neurons.  相似文献   
159.
BACKGROUND: To evaluate the efficacy and toxicity of cisplatin/etoposide continuous infusion chemotherapy for cancer of unknown primary site in Taiwan, a region with a high prevalence of endemic viral infections. METHOD: Between April 1994 and February 1996, 20 patients with a diagnosis of CUPS were treated, including 15 males and five females, of average age 63.3 years (range 41-83 years). Continuous intravenous infusion of etoposide 80 mg/m2 and cisplatin 25 mg/m2 was given for 3 days every 3 weeks. Pretreatment tumor marker and viral serology studies were performed for baseline evaluation. Nearly two-thirds of the patients had poorly differentiated carcinoma. The average number of metastatic sites was 2.65 (range 1-4), with liver and lymph node involvement predominating. RESULTS: The overall response rate was 25% (95% CI 17.7-32.3%); 30.7% for poorly differentiated cancers and 25% for well differentiated cancers. Median survival was 4 months (range 1-12 months), 4.8 months for patients attaining partial response. Toxicity was moderate, grade 3 and 4 neutropenia occurred in 55% and grade 3 and 4 thrombocytopenia in 40%; other toxicities were mild. CA125 and CA199 were elevated in more than 50% of patients. Viral serology studies were not significantly different from those of the indigenous population. CONCLUSION: Etoposide and cisplatin combination chemotherapy has modest activity in patients with extensive CUPS and, at the schedule and dosage given, it is associated with moderate toxicity.   相似文献   
160.
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