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91.
We report the imaging findings in a case of pedunculated exogastric leiomyoblastoma presenting as a wandering abdominal mass. Ultrasound and computed tomography showed a large, mixed solid and cystic mass in the peritoneal cavity. Computed tomography clearly showed that the mass was connected to the stomach by a narrow stalk. Small bowel follow-through showed subtle extrinsic indentation of the gastric body. The mass wandered from the right to the left side of the peritoneal cavity during various radiologic examinations.  相似文献   
92.
BACKGROUND: Asian Americans are generally underrepresented both as volunteer blood and bone marrow donors. STUDY DESIGN AND METHODS: To investigate the risk of transfusion transmission of viruses that is associated with increasing participation by Asian American donors, antibodies to human T-lymphotropic virus (HTLV), hepatitis C, and human immunodeficiency virus in Asian American volunteers recruited as potential bone marrow donors were measured. A total of 1354 Asian Americans were enrolled in the study, of whom 54 percent were Chinese, 26 percent Japanese, 9 percent Filipino, 4 percent Korean, 3 percent Indian, and 5 percent of other Asian or mixed Asian and other ethnicity. The majority of the study population was aged 20 through 49 and of high socioeconomic status, as indicated by education and income. Viral antibodies were measured with both screening enzyme-linked immunosorbent assays and supplemental testing, and polymerase chain reaction was used to resolve discrepant HTLV results. RESULTS: Confirmed seroprevalence rates for HTLV were 0.15 percent with one manufacturer's Western blot and 0.3 percent with the other; however, no sample was positive for HTLV types I or II in polymerase chain reaction. Confirmed seroprevalence to hepatitis C virus was 0.5 percent. No subject was seropositive for human immunodeficiency virus. CONCLUSION: On the basis of the moderate size and high education level of this study population, it is concluded that Asian American volunteer bone marrow donors do not pose a greater risk for transmission of HTLV type I or II, human immunodeficiency virus, or hepatitis C virus than does the average American blood donor.  相似文献   
93.
True or sham plasma exchange was done weekly for 20 weeks in patients in two of the randomization groups in a prospective, blind clinical trial of experimental treatments for multiple sclerosis. Because patients could be randomized to receive sham plasma exchange and placebo medications, it was decided when the trial was designed that the use of fistulae, arteriovenous shunts, venous cutdowns, or other aggressive forms of venous access would not be permitted for any patient. Accordingly, patients judged to have inadequate superficial antecubital veins were ineligible for the trial. To date, only 13 (4.4%) of 294 patients considered for entry into the trial have been rejected on these grounds. In only 4 of the 93 patients undergoing exchange was it necessary to discontinue plasma exchange because of inadequate venous access. In 79.3 percent of the 1207 exchanges done in these patients, there were no problems of any kind with venous access. In 5.4 percent of these 1207 exchanges, it was necessary to terminate the procedure prematurely because of difficulties with patients' veins. Thus, the great majority of patients free of serious systemic illness (other than chronic progressive multiple sclerosis) can undergo weekly plasma exchange for up to 20 weeks using superficial antecubital veins without the need to resort to more invasive methods of venous access.  相似文献   
94.
Erythropoiesis is critically dependent on erythropoietin (EPO), a glycoprotein hormone that is regulated by hypoxia-inducible factor (HIF). Hepatocytes are the primary source of extrarenal EPO in the adult and express HIF-1 and HIF-2, whose roles in the hypoxic induction of EPO remain controversial. In order to define the role of HIF-1 and HIF-2 in the regulation of hepatic EPO expression, we have generated mice with conditional inactivation of Hif-1alpha and/or Hif-2alpha (Epas1) in hepatocytes. We have previously shown that inactivation of the von Hippel-Lindau tumor suppressor pVHL, which targets both HIFs for proteasomal degradation, results in increased hepatic Epo production and polycythemia independent of Hif-1alpha. Here we show that conditional inactivation of Hif-2alpha in pVHL-deficient mice suppressed hepatic Epo and the development of polycythemia. Furthermore, we found that physiological Epo expression in infant livers required Hif-2alpha but not Hif-1alpha and that the hypoxic induction of liver Epo in anemic adults was Hif-2alpha dependent. Since other Hif target genes such phosphoglycerate kinase 1 (Pgk) were Hif-1alpha dependent, we provide genetic evidence that HIF-1 and HIF-2 have distinct roles in the regulation of hypoxia-inducible genes and that EPO is preferentially regulated by HIF-2 in the liver.  相似文献   
95.
Introduction: We sought to the ideal sites for botulinum toxin injection by examining the intramuscular nerve patterns of the ankle invertors. Methods: A modified Sihler method was performed on the flexor hallucis longus, tibialis posterior, and flexor digitorum longus muscles (10 specimens each). The muscle origins, nerve entry points, and intramuscular arborization areas were measured as a percentage of the total distance from the most prominent point of the lateral malleolus (0%) to the fibular head (100%). Results: Intramuscular arborization patterns were observed at 20–50% for the flexor hallucis longus, 70–80% for the tibialis posterior, and 30–40% for the flexor digitorum longus. Conclusions: These findings suggest that treatment of muscle spasticity of the ankle invertors involves botulinum toxin injections in specific areas. These areas, corresponding to the areas of maximum arborization, are recommended as the most effective and safest points for injection. Muscle Nerve 53 : 742–747, 2016  相似文献   
96.
La nécrosectomie transgastrique semble être une alternative présentant peu de risques de traitement pour les patients gravement atteints. Cependant, il manque à ce jour, une analyse des risques du procédé sur un nombre suffisant de patients; il est urgent de procéder à des collectes de données multicentriques. Il s’agit de procédés endoscopiques complexes, qui nécessitent une grande expérience, et le traitement de chaque patient devrait être planifié de fa?on interdisciplinaire en collaboration avec le chirurgien. Ce procédé devrait par conséquent rester limité aux centres spécialisés.  相似文献   
97.
Objective: The aim of this study was to determine trends in the incidence of benign lesions in patients undergoing surgery for suspicious renal masses on preoperative computed tomography scan. Methods: The records of 1065 patients who underwent open consecutive partial nephrectomy (PN) or radical nephrectomy (RN) between January 2001 and December 2008 were reviewed. Patients who underwent PN during the periods 2001–2002, 2003–2004, 2005–2006, and 2007–2008 were assigned to groups 1, 2, 3 and 4, respectively. The frequencies of benign and malignant lesions in these groups were assessed according to size and histology subtypes. Results: The ratio of PN to RN was 12.4%, 18.3%, 24.3% and 37.2% in groups 1, 2, 3 and 4, respectively (P < 0.05). The mean size of resected lesions was 2.6 cm (range 0.8–6.2 cm). Of the 290 cases, histopathology revealed benign findings in 52 (17.9%). Benign pathology was found in three of 18 cases (16.7%) in group 1, seven of 36 cases (19.4%) in group 2, 12 of 63 cases (19.0%) in group 3 and 30 of 173 cases (17.3%) in group 4. There was no significant difference in the frequency of benign histology among groups. Conclusion: PN, as opposed to RN, has shown a rising tendency over time. The frequency of benign pathology findings after PN for suspicious renal masses on preoperative computed tomography imaging has not decreased. Proper management should favor nephron‐sparing surgery for renal lesions if such lesions can be removed satisfactorily with PN.  相似文献   
98.
Objectives: To analyze the characteristics and the prognostic significance of chromophobe renal cell carcinomas (chRCC). Methods: Data about 2981 patients with non‐metastatic renal cell carcinomas (RCC) at the time of surgery were retrospectively collected from 26 institutions between 1998 and 2008. All patients had undergone partial or radical nephrectomies. Of the 2981 patients, 2602 patients with conventional RCC (cRCC) and 148 with chRCC were studied. Clinical and pathological parameters were determined in all patients. Recurrence‐free survival (RFS) and cancer‐specific survival (CSS) were assessed. Results: Patients with chRCC differed significantly from those with cRCC on the following parameters: younger age (P = 0.026), greater female ratio (P < 0.001), and larger tumor diameter (P < 0.001). Both groups were alike with respect to body mass index (P = 0.943), Eastern Cooperative Oncology Group performance status (P = 0.163), T stage (P = 0.375), and Fuhrman's grade (P = 0.134). The 5‐year RFS rates in patients with chRCC and cRCC were 82.7% and 83.3%, respectively (P = 0.762). The 5‐year CSS rates in patients with chRCC and cRCC were 88.8% and 92.2%, respectively (P = 0.980). Both groups showed equivalent oncological outcomes in terms of RFS and CSS for cases stratified by T stage and Fuhrman's grade. In multivariate analysis, the histological subtype was not retained as an independent prognostic variable (RFS: P = 0.893; CSS: P = 0.729). Conclusions: Despite being significantly different from cRCC in terms of several clinical and pathological parameters, chRCC shows equivalent oncological outcomes.  相似文献   
99.
Objective: To examine the rate of Gleason sum upgrading (GSU) from a sum of 6 to a Gleason sum of ≥7 in patients undergoing radical prostatectomy (RP), who fulfilled the recommendations for low dose rate brachytherapy (Gleason sum 6, prostate‐specific antigen ≤10 ng/mL, clinical stage ≤T2a and prostate volume ≤50 mL), and to test the performance of an existing nomogram for prediction of GSU in this specific cohort of patients. Methods: The analysis focused on 414 patients, who fulfilled the European Society for Therapeutic Radiation and Oncology and American Brachytherapy Society criteria for low dose rate brachytherapy (LD‐BT) and underwent a 10‐core prostate biopsy followed by RP. The rate of GSU was tabulated and the ability of available clinical and pathological parameters for predicting GSU was tested. Finally, the performance of an existing GSU nomogram was explored. Results: The overall rate of GSU was 35.5%. When applied to LD‐BT candidates, the existing nomogram was 65.8% accurate versus 70.8% for the new nomogram. In decision curve analysis tests, the new nomogram fared substantially better than the assumption that no patient is upgraded and better than the existing nomogram. Conclusions: GSU represents an important issue in LD‐BT candidates. The new nomogram might improve patient selection for LD‐BT and cancer control outcome by excluding patients with an elevated probability of GSU.  相似文献   
100.
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