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131.
Schizophrenia unfolds during the late period of brain maturation, while myelination is still continuing. In the present study, we used MRI and T2 relaxation analysis to measure the myelin water fraction in schizophrenia. In schizophrenia (n=30) compared with healthy subjects (n=27), overall white matter showed 12% lower myelin water fraction (P=0.031), with the most prominent effects on the left genu of the corpus callosum (36% lower, P=0.002). The left anterior genu was affected in both first-episode (P=0.035) and chronic patients (P=0.011). In healthy subjects, myelin water fraction in total white matter and in frontal white matter increased with age, and with years of education, indicating ongoing maturation. In patients with schizophrenia, neither relation was statistically significant. Post-mortem studies of anterior frontal cortex demonstrated less immunoreactivity of two oligodendrocyte-associated proteins in schizophrenia (2',3'-cyclic nucleotide 3'-phosphodiesterase by 33%, P=0.05; myelin-associated glycoprotein by 27%, P=0.14). Impaired myelination in schizophrenia could contribute to abnormalities of neural connectivity and persistent functional impairment in the illness.  相似文献   
132.
Endoscopic management of CP is generally safe, minimally invasive, and often effective for years, does not hinder further surgery, and can be repeated. It should be applied as a first-line approach to improving the clinical condition of patients with this chronic disease. The best results are obtained when endoscopic treatment is performed early in the course of CP. Proper patient selection, adequate expertise, and a supporting multidisciplinary infrastructure are essential. New technologies will continue to be developed and to extend the scope of therapeutic pancreatic endoscopy.  相似文献   
133.
134.
BACKGROUND: Impairment of pulmonary function is common after upper abdominal operations. The purpose of this study was to compare postoperative pulmonary function and analgesic requirements in patients undergoing either laparoscopic or open Roux-en-Y gastric bypass (GBP). STUDY DESIGN: Seventy patients with a body mass index of 40 to 60 kg/m2 were randomly assigned to undergo laparoscopic (n = 36) or open (n = 34) GBP. The two groups were similar in age, gender, body mass index, pulmonary history, and baseline pulmonary function. Pulmonary function studies were performed preoperatively and on postoperative days 1, 2, 3, and 7. Oxygen saturation and chest radiographs were performed on both groups preoperatively and on postoperative day 1. Postoperative pain was evaluated using a visual analog scale and the amount of narcotic consumed was recorded. Data are presented as mean +/- standard deviation. RESULTS: Laparoscopic GBP patients had significantly less impairment of pulmonary function than open GBP patients on the first three postoperative days (p < 0.05). By the 7th postoperative day, all pulmonary function parameters in the laparoscopic GBP group had returned to within preoperative levels, but only one parameter (peak expiratory flow) had returned to preoperative levels in the open GBP group. On the first postoperative day, laparoscopic GBP patients used less morphine than open GBP patients (46 +/- 31 mg versus 76 +/- 39 mg, respectively, p < 0.001), and visual analog scale pain scores at rest and during mobilization were lower after laparoscopic GBP than after open GBP (p < 0.05). Fewer patients after laparoscopic GBP than after open GBP developed hypoxemia (31% versus 76%, p < 0.001) and segmental atelectasis (6% versus 55%, p = 0.003). CONCLUSION: Laparoscopic gastric bypass resulted in less postoperative suppression of pulmonary function, decreased pain, improved oxygenation, and less atelectasis than open gastric bypass.  相似文献   
135.
OBJECTIVE: To assess the presence of Yersinia enterocolitica in otherwise healthy pigs slaughtered for human consumption. METHODS: One hundred pharyngeal tonsils were sampled in a slaughterhouse in the state of Mexico. The minimum sample size (n=100) was calculated based on a preliminary sample of 20 cases, which had 20% positive cases. The collected tonsil samples were inoculated in Rappaport broth, and Salmonella-Shigella and McConkey media. The biotyping identification process was based on biochemical and serological tests using O:3, O:8 and O:9 antisera. RESULTS: Twenty-two isolates were obtained. Most were biotype 1 (8 cases of O:3 and 8 cases of O:9), but 6 cases could not be serotyped. None of the isolates were of O:8 group. CONCLUSIONS: This was the first time that Y. enterocolitica serotypes were isolated from pig tonsils in Mexico. Its importance rely on the fact that the isolated serotypes are the most commonly found in public health problems.  相似文献   
136.
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   
137.
We report a patient with M2 acute non-lymphocytic leukemia and a complex karyotype: 47,XY,t(5;7)(q34;q21), +8. After chemotherapy with Daunomycin and Arabinosyl Cytosine, a complete remission was reached, but two months later he relapsed and died because of sepsis. Only 5 other cases with translocations involving chromosomes 5 and 7 have been described, but with different breakpoints. Several genes related to cell proliferation and maturation have been identified on the long arms of chromosomes 5 and 7. The possible involvement of specific genes located at or very close to the breakpoints is hypothesized.  相似文献   
138.
Aim: This randomized clinical trial evaluated the effects of an essential oils-containing mouthrinse for full-mouth disinfection.
Material and Methods: Fifty patients were assigned to receive full-mouth disinfection with either essential oils or placebo. At baseline, 2 and 6 months of treatment the primary outcomes probing depth (PD), plaque index (PlI) and modified gingival index (MGI) were monitored. Additional monitoring included bacterial presence (by polymerase chain reaction) in subgingival, saliva and tongue samples; flows, pH, total protein and alkaline phosphatase salivary levels. The following statistics were used: anova , Student's t -test, χ 2 and Kruskal–Wallis ( p <0.05).
Results: Mean PD3.5 mm was reduced over time in both the placebo and the test groups, but there was no difference in PD reduction between groups at 2 and 6 months. At 2 and 6 months, PlI and MGI showed greater reductions in the test group than in the placebo group. Porphyromona gingivalis was not reduced in any site. At 6 months, Campylobacter rectus increased in both groups, while Tannerella forsythensis decreased subgingivally in the test group. S. sanguinis increased, except subgingivally, in the placebo group. Salivary pH and flows were not altered. Total protein reduced only in the test group. Alkaline phosphatase did not change in either group.
Conclusions: Essential oils for full-mouth disinfection showed clinical benefits, namely reducing plaque and gingival inflammation without altering basic salivary parameters.  相似文献   
139.
The clinical and epidemiological features, as well as complications presented by 39 patients with Bothrops, Porthidium and Bothriechis snakebites, are described. Patients were admitted during 1 year in 25 hospitals of Antioquia and Chocó and then, they were transferred to the Hospital Universitario San Vicente de Paúl in Medellín, 30 of them because of the presence of complications, eight because of lack of antivenoms and another one because of the desire of his relatives. Thirty--one (79.5%) of the patients were male, 13 (33.3%) children, 59% of them were bitten at the lower extremities, the majority (74.4%) by Bothrops asper. Twenty-one (53.8%) of the patients were initially attended by traditional healers and sought medical attention at the local hospitals after 2h in 87.2% of the cases. Edema (100%), hemorrhage (74.4%), blistering (38.5%) and necrosis (38.5%), were the local signs of envenomation, while blood coagulation alteration (79.5%), hematuria (74.4%), gingival bleeding (43.6%), hypovolemic shock (23.1%) and oliguria (23.1%), were the systemic signs of envenomation. The final grade of envenomation was severe in 29 patients (74.4%). Thirty patients (76.9%) had one or more complications of the envenomation: acute renal failure (ARF), 15 (38.5%); soft-tissue infection, 12 (30.8%); central nervous system (CNS) hemorrhage, 5 (12.8%); compartment syndrome, 3 (7.7%); soft--tissue hematomas, 6 (15.4%); and Abruptio placentae, one (2.6%). There were four deaths (10.3%), two from ARF and two from cerebral hemorrhage. Fourteen other patients (35.9%) had sequelae. The onset of serotherapy after 2h of the bite was associated with the occurrence of ARF and CNS hemorrhage (p=0.02), as well as the risk of death and sequelae (RR=2.5).  相似文献   
140.
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