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131.
A seven-year-old girl was referred to our clinic with absent eyelids and a mass which was gradually increasing in size from the right orbit. The child was diagnosed to have Fraser syndrome (cryptophthalmos, abnormal genitalia, mental deficiency, renal agenesis and abnormal ears). On examination, there was cryptophthalmos and a cystic swelling arising from the right orbit. The cyst was removed. On gross examination, there was a posterior eyeball with normal optic nerve. Placed in the anterior part of the eyeball was a cyst measuring about 2 cm in diameter filled with a yellow-coloured fluid. The cavity of the eyeball was communicating with the cyst. The cyst wall was lined by a single layer of epithelium. The posterior eyeball had well developed sclera, choroid, retina and optic nerve. There have been many reports of cryptophthalmos in Fraser syndrome. The most common eye deformity described with cryptophthalmos is microphthalmia or anophthalmia. To the author's knowledge, there is one other report of cystic eyeball with cryptophthalmos in the literature. The cyst seems to be due to a surface ectodermal anomaly, rather than a neuro-ectodermal anomaly where there is failure of invagination of the primary optic cup during development. The cyst wall in those cases has inverted retinal elements. In our case, differentiation of retinal elements was present in the posterior eyeball. The abnormality seemed to lie in the derivatives of surface ectoderm, namely the eyelids and the anterior segment structures.  相似文献   
132.
BACKGROUND: Preoperative delineation of any vascular anomalies offers planning for possible alteration of surgical procedures, especially in pediatric recipients undergoing living-related liver transplantation. PURPOSE: We assess the efficacy of three-dimensional (3D) multislice computed tomography (CT) angiography in the hope of replacing conventional angiography as the pretransplant evaluation of the hepatic vascular system for potential recipients of liver transplantation. METHODS: 3D CT angiography was performed in 38 children with biliary atresia. Conventional angiography was also performed in the first 15 patients. Twelve patients underwent living-related liver transplantation. The findings on 3D CT angiography were compared with conventional angiography and operative findings. RESULTS: 3D CT angiography was successfully performed in 37 pediatric patients. All findings of 3D CT angiography on hepatic artery, portal vein, and inferior vena cava paralleled those of catheter angiography and operative findings. Four patients were unsuitable to receive living grafts because of pathologic insults of the hepatic artery (one patient) and the portal vein (three patients). Three patients were advised to undergo a venous graft for portal anastomoses. Eight patients demonstrated portosystemic shunts that may require closure. CONCLUSION: 3D CT angiography proves to be a better tool in the demonstration of the vascular system and identification of pathologic insults in pediatric patients. It is superior to conventional angiography because it is less invasive, more convenient, and more efficient in providing thorough preoperative information that would have a major impact on patient selection and surgical planning.  相似文献   
133.

OBJECTIVE:

To ascertain the variation in asthma management practices among paediatricians and family physicians to determine how to improve care.

DESIGN:

Questionnaire study of paediatricians and family physicians that focused on the use of beta2-agonists, inhaled corticosteroids, patient asthma education, quantitative measurements of airflow and diagnostic investigations for asthma. Case scenarios were used in the questionnaire.

RESULTS:

The response rate was 66% (415 of 632) among paediatricians and 42% (1156 of 2750) among family physicians. In general, both groups followed consensus guidelines. There were some differences in management practices among paediatricians and family physicians. Paediatricians were more likely to develop an action plan and less likely to use xanthines or inhaled anticholinergic agents. However, family physicians were more likely to use spirometry or home peak expiratory flow rates to make a diagnosis of asthma.

CONCLUSION:

Family physicians and paediatricians require a different focus on educational interventions to improve the care of children with asthma.  相似文献   
134.
OBJECTIVE: To examine the association between emergency department length of stay (EDLOS) and inpatient length of stay (IPLOS). DESIGN: Retrospective review of presentations and admissions data. SETTING: Three metropolitan hospitals in Melbourne, 1 July 2000 to 30 June 2001. MAIN OUTCOME MEASURES: Mean IPLOS for four categories of EDLOS (12 hours); excess IPLOS, defined as IPLOS exceeding state average length of stay; odds ratios for excess IPLOS adjusted for age, sex and time of presentation. RESULTS: 17 954 admissions were included. Mean IPLOS for the four categories of EDLOS were 12 hours, 7.20 days (P < 0.001). The corresponding excess IPLOS were 0.39, 1.30, 1.96 and 2.35 days (P < 0.001). Compared with EDLOS 4-8 hours, odds ratios (95% CIs) for excess IPLOS associated with the other three categories of EDLOS were 12 hours, 1.49 (1.36-1.63), after adjusting for elderly status, sex and time of ED presentation. CONCLUSION: EDLOS correlates strongly with IPLOS, and predicts whether IPLOS exceeds the state benchmark for the relevant diagnosis-related group, independently of elderly status, sex and time of presentation to ED. Strategies to reduce EDLOS (including countering access block) may significantly reduce healthcare expenditure and patient morbidity.  相似文献   
135.
136.
Perforation with extravasation of barium is a rare complication of contrast enema examination of the large bowel with a high associated mortality rate. The experience of performing a re-laparotomy in a patient previously exposed to barium peritonitis is even less common. We describe an elderly male patient with a Hartmann's procedure performed a year previously, presenting with peritonitis following barium enema evaluation of the proximal colon via an end descending colon stoma. Emergency laparotomy, segmental bowel resection and liberal peritoneal toilet resulted in a satisfactory outcome. The patient had a subsequent successful reversal of his Hartmann's procedure nine months later despite the presence of dense barium induced adhesions. This potentially preventable iatrogenic complication is discussed in this report, which is supplemented by a brief review of the English literature.  相似文献   
137.
138.
Yu SC  Liew CT  Lau WY  Leung TW  Metreweli C 《Radiology》2001,218(1):195-199
PURPOSE: To determine the accuracy of ultrasonography (US)-guided percutaneous biopsy in diagnosing malignant neoplasms for hepatic lesions 1 cm or smaller. MATERIALS AND METHODS: In this prospective study, 64 consecutive patients with 74 discrete focal hepatic lesions depicted at US were referred for liver biopsy to confirm the exact nature of the lesions. Mean lesion size was 0.84 cm +/- 0.13 (range, 0.5-1.0 cm). Biopsy was performed with an 18-gauge automated biopsy gun in 46 lesions (once [n = 37], twice [n = 7], three times [n = 2]) or a 22-gauge needle in 28 lesions (once [n = 23], twice [n = 4], three times [n = 1]). Measures were taken to ensure accurate and effective lesion sampling. The histologic diagnosis of malignant tumor and findings on follow-up US images of "benign" nodules for 15-39 months were the criterion standard. RESULTS: No complications occurred. All specimens obtained were sufficient for diagnosis. Histologic examination revealed various types of primary and secondary malignant tumors (n = 44), hemangioma (n = 5), cirrhosis (n = 13), focal fatty change (n = 8), focal fatty sparing (n = 2), and abscess (n = 2). The diagnostic discrimination of US-guided biopsy in diagnosing malignant tumors in these small lesions was sensitivity, 98%; specificity, 100%; positive predictive value, 100%; negative predictive value, 97%; and accuracy, 99%. CONCLUSION: Percutaneous biopsy under US control is highly accurate in providing a definitive histologic diagnosis of malignant neoplasms for small hepatic lesions if measures for ensuring precise and effective lesion sampling are taken.  相似文献   
139.
Phospholipases A2 were purified from the venoms of Asian monotypic crotalinae snakes including Callosellasma, Hypnale, Deinagkistrodon, and Tropidolaemus by a combination of gel filtration and reversed-phase chromatographic methods. One to four isoforms of the enzyme were found in each of the venoms. The venom enzymes were subjected to N-terminal sequencing up to the 30th amino acids, and their molecular weights were analyzed by electrospray-ionization mass spectrometry. Homologous antiplatelet phospholipase with a conserved Glu 6 residue was found in each of the venoms. Basic phospholipases with Trp 6 (W6) but without detectable enzyme activities were also isolated from the venom of C. rhodostoma, H. hypnale, and T. wagleri. These W6 enzymes showed strong heparin-binding affinity and capable of inducing edema in rat paws. The fact that the venoms of Callosellasma and Hypnale contain similar types of phospholipases is in accord with recent reports that these two taxa formed a clade. Deinagkistrodon venom does not contain phospholipase variants other than the Glu-6 subtype as Trimeresurus, Agkistrodon, and Protobothrops venoms do. Interestingly, the Glu-6 enzyme from T. wagleri venom has a molecular weight of 15,319 Daltons, higher than those of most other venom phospholipases. Our results show that new types of the enzyme are more likely to be found in the venom of monotypic species; the amino acid sequence data or the subtypes of venom-phospholipases are potentially useful as markers or a character system for studying higher-order systematics of venomous snakes.  相似文献   
140.
Frequent allelic loss on chromosome 9 in hepatocellular carcinoma   总被引:6,自引:0,他引:6  
Hepatocellular carcinoma (HCC) is a common malignancy worldwide and highly associated with chronic virus-B or -C infection and cirrhosis. Molecular studies have shown high frequency of loss of heterozygosity (LOH) in some specific chromosome regions, but LOH on chromosome 9 in HCC has not been thoroughly investigated. In our investigation of chromosome 9 with 19 polymerase-chain-reaction (PCR)-based polymorphic microsatellite markers, 30 of 48 HCC tissue samples (63%) had LOH, and a distinct common deletion region and a region of loss were identified. The first region was located at the 9p21 region and the minimal deletion region was located between loci D9S1747 and D9S1748. This is a region of approximately 200 kb which includes the p16 tumor-suppressor gene. A region of loss was located on 9p13 to 9q33. The putative tumor-suppressor gene for nevoid-basal-cell-carcinoma syndrome (NBCCS) at 9q22.3 resides within this region. In addition to LOH, 4 HCC cases showed possible homozygous deletions at 9p21 with markers D9S1748, D9S1752 and D9S171 by multiplex PCR analysis. In 3 cases, the minimal region of possible homozygous deletion was approximately 300 kb and was defined between markers D9S1747 and D9S1752. Since this deletion region includes both the p15 and the p16 tumor-suppressor genes, these genes were possibly inactivated by homozygous deletion in HCC. In addition, a second region of possible homozygous deletion was present on the centromeric side of 9p21. However, these changes are not associated with age, gender, size or tumor-cell differentiation. Our data also suggest that inactivation of the p16 and the p15 genes and the possibility of other unknown tumor-suppressor genes located on these defined deleted regions of chromosome 9 may be involved in the pathogenesis of HCC.  相似文献   
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