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991.
RATIONALE AND OBJECTIVES: To determine different countries' trend of contribution to clinical radiology journals and its relationship with impact factor. MATERIALS AND METHODS: All the journals, which publish articles on clinical radiology, were selected from the category of Radiology and Nuclear Medicine group of journals, and articles published in these journals between 1991 and 2000 were searched for the authors' affiliation using the Medline database. Then, share of research output of the top-ranking 20 countries was determined along with the trend over time. Also, the relationship of different countries' contribution with the impact factor of journals was examined by cross-sectional time-series linear model. RESULTS: Of total articles (38,359), the United States' share for the selected journals in clinical radiology was 43.2% (16,582 articles) and ranked top in the world, followed by the United Kingdom (9.9%) and Japan (8.0%). The recent increase in the share was statistically significant for Japan, France, Germany, Italy, South Korea, Turkey, Spain, Switzerland, Austria, and China. On the other hand, the United States, United Kingdom, and Canada showed a significant negative trend. Among the top-ranking 10 countries, the US contribution was significantly higher to journals with high-impact factors, whereas the opposite was true for France. CONCLUSION: The United States, United Kingdom, and Canada showed a negative trend over the last decade in terms of proportion of contribution of articles to the clinical radiology journals. However, only the United States published more articles in high-impact factor journals.  相似文献   
992.
BACKGROUND: The 5-HT3 receptor is a serotonin receptor believed to reside on enteric neurons. However, several studies belie an exclusive neural localization. Our hypothesis is that the 5-HT3 receptor agonist, 2-methyl-5-HT (2Me5HT), induces chloride secretion despite neural blockade, which can be blocked by a 5-HT3 receptor antagonist. METHODS: Rat distal colon was stripped of its muscularis, mounted as mucosal sheets in Ussing chambers, and short-circuited. Adjacent sheets were pretreated with 1 micromol/L of the neurotoxin, tetrodotoxin, and incubated with 2Me5HT (50 micromol/L) alone or with a 5-HT3 (0.3 micromol/L ondansetron or 0.3 micromol/L tropisetron) or a 5-HT4 (0.3 micromol/L GR11808) receptor antagonist. Short-circuit current (I(sc)) was measured continuously. RESULTS: 2Me5HT caused an increase in I(sc), which was significantly (P <.01, repeated measures analysis of variance) inhibited by ondansetron (n = 8) and tropisetron (n = 5) but not by GR11808. CONCLUSIONS: A 5-HT3 receptor is present at the mucosal level that mediates chloride secretion by a nonneural pathway.  相似文献   
993.
Although not a typical site, the pancreas does occasionally harbor metastatic disease. Management of these metastases differs from the management of conventional primary cancers. Our case is one of an 85-year-old female presenting with obstructive jaundice and whose workup revealed a pancreatic mass. Her past medical history included a mastectomy 14 years previous for invasive lobular carcinoma. She underwent celiotomy, and an intraoperative diagnosis of metastatic lobular carcinoma of the breast was made based on frozen section. Due to pulmonary metastasis and vascular infiltration, which precluded pancreatoduodenectomy, the patient underwent palliative bypass and fared well postoperatively. With more aggressive management of primary breast cancers in the past decade, isolated metastatic disease is of increasing concern and raises questions about surgical strategies to be implemented with these patients. For instance, should palliative treatment be considered or should a radical intention to cure procedure be performed despite the metastatic disease? Factors favoring radical procedures include prolonged lag phase between the primary and the recurrence; presence of well-differentiated tumors; and isolated metastatic disease. Primary lung and renal cancers metastasize more frequently than breast cancers do to the pancreas. Hence, existing literature has not clearly defined indications for radical treatment of metastatic breast cancers to the pancreas. Based on experiences with metastatic renal and lung cancers, one can reasonably infer that radical procedures performed on selected cases could possibly achieve a cure or prolonged disease-free survival. The key factor in determining whether the patient undergoes palliative versus radical treatment is a slow growth pattern of the tumor, characterized by a prolonged lag phase between the primary and the metastatic disease.  相似文献   
994.
Pakistan is a high-fertility country with elevated levels of maternal mortality and unmet need for family planning. Limited access to and poor quality of reproductive health services and gender-related problems comprise the major explanations for these poor indicators. The authors designed an intervention to address some of these issues and implemented it on a quasi-experimental basis in Bhalwal Tehsil of the Sargodha district of Punjab. The intervention introduced a client-centered approach to providing reproductive health services, including family planning and infant, child, and maternal health care. The intervention consisted of training health-care providers based in fixed-location clinics and in communities. It introduced the concept of SAHR (an acronym for salutation, assessment, help, and reassurance), to inculcate a client-centered approach to care that acknowledges explicitly and addresses a client's gender and power relations within her family and household. Results of the intervention indicate significant effects on providers' behavior related to SAHR elements. The changes provide demonstrable evidence that the public sector can shift toward client-centered services in reproductive health care in a challenging setting.  相似文献   
995.
Laparoscopic adrenalectomy is now used worldwide to resect adrenal adenomas and other adrenal tumors recently introduced in Pakistan. Two cases of endocrine hypertension, due to Conn s syndrome, undergoing laparoscopic adrenalectomy for the first time here, are reported.  相似文献   
996.
The enteric protozoa, Cryptosporidium, Giardia and Entamoeba histolytica, cause diarrhea in children. We investigated the association of enteric protozoan-associated diarrheal illness with the nutritional status and growth of preschool children in Dhaka, Bangladesh. The subjects were 221 children aged 2-5 years who were followed prospectively for diarrheal illness for 3 years. The weight and height of the children were measured at entry and at 4-month intervals. Cryptosporidium and E. histolytica were diagnosed with commercially available stool antigen detection kits. Giardia was diagnosed by conventional microscopy. Cryptosporidium- and Giardia-associated diarrheal illness was not associated with the growth of the children. Children with E. histolytica-associated diarrheal illness had lower weight for age Z-score changes (-0.103+/-0.120 vs. 0.176+/-0.052, P=0.038). Similarly, the change in height for age Z-score was lower in children with E. histolytica-associated diarrheal illness (-0.348+/-0.186 vs. 0.142+/-0.08, P=0.018). Children with E. histolytica-associated diarrheal illness were 2.93 times (95% CI 1.01-8.52, P=0.047) more likely to be malnourished and 4.69 times (95% CI 1.55-14.18, P=0.006) more prone to be stunted. Entamoeba histolytica-associated diarrheal illness was negatively associated with the growth of preschool children.  相似文献   
997.
A study of the epidemiology of malaria transmission was undertaken in 13 tribal villages located in forest and plain areas of Sundargarh District of Orissa state, India, from January 2001 to December 2003. In forest areas, intense transmission of malaria is attributed to the highly anthropophagic vector Anopheles fluviatilis sibling species S and is complemented by A. culicifacies sibling species C. In plain areas, A. culicifacies sibling species C is responsible for malaria transmission. The entomological inoculation rate in the forest and plain areas was 0.311 and 0.014 infective bites/person/night, respectively, during 2003. Malaria transmission is perennial both in forest and plain areas but is markedly low in the plain area compared with the forest area. Plasmodium falciparum accounted for 85.0% of the total malaria cases during the study period. In forest and plain areas, the number of P. falciparum cases per 1000 population per year was 284.1 and 31.2, respectively, whereas the parasite rate was 14.0% and 1.7%, respectively. In forest areas, clinical malaria occurs more frequently in children aged 0-5 years and declines gradually with increasing age. The study showed that villages in forest and plain areas separated by short geographical distances have distinct epidemiology of malaria transmission.  相似文献   
998.
Previous studies have suggested that susceptibility to arsenic toxicity could be influenced by micronutrients, in particular selenium, methionine, and beta-carotene. A case-control study was conducted in West Bengal, India, in a region known to have groundwater arsenic contamination, to determine whether differences in micronutrient status contribute to susceptibility to arsenic-induced skin lesions. Micronutrient status was assessed by blood levels of specific micronutrients and metabolic indicators. Blood was obtained from 180 cases with skin lesions and 192 controls. Blood assays measured micronutrients and carotenoids (folate, selenium, vitamin B12, vitamin B6, retinol, alpha-tocopherol, lutein/zeaxanthin, beta-carotene, lycopene, beta-cryptoxanthin) and metabolic indicators such as glucose, cholesterol, transthyretin, amino acids, and proteins potentially associated with methylation (cysteine, homocysteine, methionine, glutathione). The distributions of nutrient concentrations were similar in cases and controls. The median selenium concentrations in cases and controls were both 1.15 micromol/L, and there was little evidence of differences in other micronutrients. Odds ratios (ORs) for arsenic-induced skin lesions were estimated for each quartile of nutrient concentrations, using the quartile with the highest nutrient level as the referent group. There were no clear trends associated with deficiencies of any micronutrient or metabolic indicator. For decreasing quartiles of selenium, the OR estimates were 1.00, 0.67, 0.99, 0.80; P=0.81; for methionine, the OR estimates were 1.00, 0.83, 0.78, 0.72; P=0.29. For beta-carotene, the ORs were 1.00, 0.53, 0.51, 0.96, demonstrating no increased risk at the lower quartiles. The measured micronutrients and metabolic indicators investigated do not appear to modify the risk of developing arsenic-induced skin lesions. The lack of any trend of increasing risk with lower selenium, vitamin E, and beta-carotene concentrations has important implications for proposed therapeutic interventions. The emphasis of interventions should be on reducing arsenic exposure.  相似文献   
999.
Kane SM  Dave A  Haque A  Langston K 《Orthopedics》2006,29(4):363-366
The etiology of rotator cuff disease is multifactorial. One theory behind the high incidence of rotator cuff tears in the shoulder is that the supraspinatus/infraspinatus tendon contains a zone of relative avascularity in the area proximal to its insertion at the greater tuberosity. Tobacco smoking is known to contribute to microvascular disease, and it can be hypothesized that smoking tobacco further compromises the vascular supply to the supraspinatus/infraspinatus tendon, thus increasing the incidence of tendinous pathology in the rotator cuff. This article evaluates the rotator cuffs of 72 shoulders in 36 cadavers and compares the incidence of macroscopic and microscopic disease within the rotator cuff tendon. Microscopic evaluation of the accompanying lung tissue from the respective cadaver also was performed. As a result, we were able to determine the presence or absence of a smoking history or emphysema from each cadaver as it related to rotator cuff disease in the shoulder. Of the 36 shoulders that exhibited macroscopic rotator cuff tears, 23 were from cadavers with a history of smoking compared to only 13 from cadavers with no history of smoking. Furthermore, the presence of advanced microscopic rotator cuff pathology (Grade 3 or 4 fibrous degeneration) was more than twice as likely in the cadavers with a history of smoking (22/32) compared to only 10 of 32 shoulders from cadavers with no history of smoking. While none of this data was statistically significant due to the insufficient number of subject cadavers, strong trends were noted in these findings.  相似文献   
1000.
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