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991.
Malignant gastric outlet obstruction(MGOO) is a clinical condition characterized by the mechanical obstruction of the pylorus or the duodenum due to tumor compression/infiltration, with consequent reduction or impossibility of an adequate oral intake. MGOO is mainly secondary to advanced pancreatic or gastric cancers, and significantly impacts on patients' survival and quality of life.Patients suffering from this condition often present with intractable vomiting and severe malnutrition, which further compromise therapeutic chances. Currently,palliative strategies are based primarily on surgical gastrojejunostomy and endoscopic enteral stenting with self-expanding metal stents. Several studies have shown that surgical approach has the advantage of a more durable relief of symptoms and the need of fewer re-interventions, at the cost of higher procedure-related risks and longer hospital stay. On the other hand, enteral stenting provides rapid clinical improvement, but have the limit of higher stent dysfunction rate due to tumor ingrowth and a subsequent need of frequent reinterventions. Recently, a third way has come from interventional endoscopic ultrasound, through the development of endoscopic ultrasound-guided gastroenterostomy technique with lumen-apposing metal stent. This new technique may ideally encompass the minimal invasiveness of an endoscopic procedure and the long-lasting effect of the surgical gastrojejunostomy, and brought encouraging results so far, even if prospective comparative trial are still lacking. In this Review, we described technical aspects and clinical outcomes of the above-cited therapeutic approaches, and discussed the open questions about the current management of MGOO.  相似文献   
992.
Endometriosis is a gynecological condition that presents as endometrial-like tissue outside the uterus and induces a chronic inflammatory reaction. Up to 15% of women in their reproductive period are affected by this condition. Deep endometriosis is defined as endometriosis located more than 5 mm beneath the peritoneal surface. This type of endometriosis is mostly found on the uterosacral ligaments, inside the rectovaginal septum or vagina, in the rectosigmoid area, ovarian fossa, pelvic peritoneum, ureters, and bladder, causing a distortion of the pelvic anatomy. The frequency of bowel endometriosis is unknown, but in cases of bowel infiltration, about 90% are localized on the sigmoid colon or the rectum. Colorectal involvement results in alterations of bowel habits such as constipation, diarrhea, tenesmus, dyschezia, and, rarely, rectal bleeding. Differential diagnosis must be made in case of irritable bowel syndrome, solitary rectal ulcer syndrome, and a rectal tumor. A precise diagnosis about the presence, location, and extent of endometriosis is necessary to plan surgical treatment. Multidisciplinary laparoscopic treatment has become the standard of care. Depending on the size of the lesion and site of involvement, full-thickness disc excision or bowel resection needs to be performed by an experienced colorectal surgeon. Long-term outcomes, following bowel resection for severe endometriosis, regarding pain and recurrence rate are good with a pregnancy rate of 50%.  相似文献   
993.
AIM:To ascertain whether caecal pH is different in patients with irritable bowel syndrome(IBS),whose primary symptoms are bloating and distension,to healthy controls.METHODS:Motility and pH data were reviewed from16 patients with RomeⅢdefined IBS and 16 healthy controls,who had undergone a wireless motility capsule(WMC)study using a standardized protocol.Motility measures were anchored around known anatomical landmarks as identified by compartmental pH changes.Sixty-minute epochs were used to quantify antral,duodenal,ileal,caecal and distal colonic contractility.The maximum and minimum pH was measured either side of the ileo-caecal junction.RESULTS:No differences were seen in motility parameters,compartmental transit times or maximal ileal pH between the two groups.Caecal pH was significantly lower in patients compared to controls(5.12±0.05vs 6.16±0.15,P<0.0001).The ileal:caecalΔchange was greater in patients than controls(-2.63±0.08 vs-1.42±0.11,P<0.0001).There was a significant correlation between caecal pH and right colonic contractility(r=0.54,P=0.002).CONCLUSION:Patients with bloating and distension have a lower caecal pH compared to controls.The measurement of caecal pH using the WMC provides a quantifiable biomarker of fermentation potentially identifying those patients that may preferentially benefit from antibiotic or dietary interventions.  相似文献   
994.
In the bid to exploit the synergy in mixed metal matrix that enhances substrate binding affinity, a composite reactive material (GLT) was prepared using lateritic soil and Gastropod shell as precursors. The defluoridation efficiency of the GLT was studied in laboratory grade fluoride contaminated water and groundwater matrix. Using experimental evidences, insight into the underlying defluoridation mechanisms of GLT was provided. The monolayer adsorption capacity (qm, mg/g) of the GLT (43.7 mg/g) was higher than that of any of the precursors (i.e. lateritic soil (qm = 2.8 mg/g) and Gastropod shell (qm = 19.8 mg/g)), which confirmed the synergistic effect of the constituents of the composite. Premised on the results of kinetic analysis, the Gibbs (?G) free energy value of formation of insoluble metal fluoride and the results of the evaluation of the effects of water chemistry on the fluoride removal efficiency of the GLT, mechanism of the defluoridation process was found to be a combination of adsorption (via ion exchange or outer sphere complexation) and precipitation reaction. Relative to the performance of the GLT in laboratory grade water, the GLT was also effective in groundwater but the value of the Langmuir monolayer adsorption capacity (qm mg/g) was lower in the groundwater system (29.76 mg/g) than in the laboratory grade water system (43.7 mg/g). The leached constituents of the GLT enhanced the values of the pH, electrical conductivity and the total dissolved solids of the treated water.  相似文献   
995.
Animal research suggests that vagus nerve stimulation (VNS) is associated with weight loss and decreased appetite. Results from human studies are mixed; some suggest that VNS affects weight whereas others do not, and it is unclear how VNS affects eating behaviors. Baseline body mass index (BMI) and VNS device settings may moderate the effects of VNS on caloric intake. This study investigates the association among BMI, VNS device settings, and caloric intake of highly palatable foods during VNS on versus VNS off sessions in 16 adult patients (62.5% female; BMI mean = 29.11 ± 6.65) using VNS therapy for either epilepsy or depression. Participants attended 2 experimental sessions (VNS on versus off) where they were presented with 4 preferred snack foods totaling 1600 calories. At the start of the session, they either had their VNS devices turned off or left on. Caloric intake was calculated by weighing foods before and after each session. BMI category (overweight/obese and lean) was the between group factor in the analysis. After controlling for covariates, an interaction of condition and BMI category (P = .03) was found. There was an interaction of condition and device output current (P = .05) and a trend toward an interaction of condition and device on time (P = .07). Excess weight may impact how neurobiological signals from the vagus nerve affect appetite and eating. Future research is needed to further elucidate this relationship.  相似文献   
996.
Background:Accurate calculation and adjustment of insulin doses is integral to maintaining glycemic control in insulin treated patients. Difficulties with insulin dose calculations may lead to poor adherence to blood glucose monitoring and insulin treatment regimes, resulting in poor metabolic control. The main objective of this study was to evaluate ease of use and user preference of a high specification touch screen blood glucose meter, which has an in-built insulin calculator, compared to patients’ usual method of testing blood glucose and deciding insulin doses.Methods:Patients with diabetes on a multiple daily injection insulin regime used the Test Meter without the insulin calculator and 1 of 3 comparator meters, each for a 7-day period. They then used the Test Meter with the in-built calculator for 10 days. Patients completed an ease of use questionnaire after each 7-day period, a preference questionnaire after the second 7-day period, and a questionnaire comparing the Test Meter with their usual method after the final 10-day period.Results:Of 164 patients who completed the study, 76% stated a preference for the Test Meter as a diabetes management tool compared to their usual method. A small number of patients preferred familiar methods and/or calculating insulin doses themselves. The log book function of meters was important to most patients.Conclusions:The Test Meter system with in-built insulin calculator supports people to better manage their diabetes and increases their confidence. Patients have different needs and preferences which should be acknowledged and supported in a patient centered health service.  相似文献   
997.
The continued detection of zoonotic viral infections in bats has led to the microbial fauna of these mammals being studied at a greater level than ever before. Whilst numerous pathogens have been discovered in bat species, infection with lyssaviruses is of particular significance from a zoonotic perspective as, where human infection has been reported, it is invariably fatal. Here we review the detection of lyssaviruses within different bat species and overview what is understood regarding their maintenance and transmission following both experimental and natural infection. We discuss the relevance of these pathogens as zoonotic agents and the threat of newly discovered viruses to human populations.  相似文献   
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1000.
BackgroundUpper gastrointestinal (UGI) bleed is a common surgical disease in sub-Saharan Africa where there is often a lack of diagnostic and interventional adjuncts such as endoscopy. This study sought to characterize the role of endoscopy in management of acute UGI bleeding.Materials and MethodsThis is a prospective observational analysis of adults presenting with an UGI bleed to a tertiary center in Lilongwe, Malawi, over two years. Patients were classified as having no endoscopy, diagnostic endoscopy, or endoscopy with variceal banding. Bivariate, survival analysis, and logistic regression analyses were used to compare intervention cohorts.Results293 patients were included with 49 patients (16.7%) receiving endoscopy with banding, 65 (22.2%) patients receiving diagnostic endoscopy only, and 179 (61.1%) receiving no endoscopy. Upon survival analysis comparing to the no endoscopy group, cox hazard modelling showed an adjusted hazard ratio over 30 days of 0.12 (95% CI 0.02, 0.88, p=0.038) for the endoscopic banding group and a hazard ratio of 0.39 (95% CI 0.13, 1.16, p=0.090) for the diagnostic endoscopy only group. Physical exam findings consistent with cirrhosis and decreasing age were independent predictors of an endoscopic diagnosis of variceal bleeding.ConclusionEsophagogastric varices are a common cause of UGI bleeding in sub-Saharan Africa and can be predicted with age and physical exam findings. Endoscopy with variceal banding has a survival benefit for patients presenting with acute UGI bleed even with relatively low utilization. Appropriately triaging patients with likely variceal bleeding and improving endoscopy capacity would likely have a significant impact on mortality.  相似文献   
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