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91.
92.
Mycobacterium bovis infection of cats is exceedingly rare in regions where bovine tuberculosis is not endemic. We describe the diagnosis and clinical management of pulmonary M. bovis infection in 2 indoor-housed cats and their association with at least 1 M. bovis–infected human in Texas, USA, in September 2012.  相似文献   
93.
Boerhaave's syndrome is the condition of spontaneous rupture of the esophagus as a consequence of the strain of emesis with or without predisposing esophageal disease. It is a condition with high mortality. We describe four patients who underwent a transthoracic esophagectomy to remove the rupture of the intrathoracic esophagus, closure of the esophageal gastric junction, fashioning of a feeding gastrostomy, and formation of a left cervical esophagostomy. Three patients underwent reconstruction with subcutaneous colon. We suggest that this method of management may be considered where primary repair is impossible in those patients too ill for prolonged reconstruction or as a salvage procedure where other methods have failed. The poor quality of life after esophagectomy is improved by reconstruction. Other surgical options include covering the repaired opening with a circumferential wrap of pleura, chest wall muscle, or omentum or closing the repair around a T-tube of large caliber. Esophageal exclusion using absorbable staples is another approach.  相似文献   
94.
BACKGROUND: Biliary strictures after liver transplantation are frequent. The long-term prognosis and predictive factors of response to endoscopic treatment are not well known. METHODS: The aim of this study was to demonstrate the role of endoscopic treatment, predictive factors of response, and outcome in patients with biliary stricture after liver transplantation. We performed a retrospective review of medical records of all consecutive post-liver transplantation patients who underwent endoscopic retrograde cholangiography in our center during the period from October 2001 to October 2006. RESULTS: Twenty-five of 43 patients referred for endoscopic retrograde cholangiography had biliary stricture. Eighteen had stricture at the area of the anastomosis alone, 2 patients had a stricture at the area of the anastomosis and also another area, and 5 had nonanastomotic biliary strictures. Twenty-one patients had a single stricture and 4 had more than 1 stricture. Initially 19 of 24 patients (79%) responded to endoscopic management with normalization of liver enzymes. Four patients (16%) did not respond clinically despite a successful endoscopic approach. All patients who did not respond to endoscopic dilation had more than 1 area of stricture. There was a significantly better response to endoscopic treatment in patients with an anastomotic stricture versus patients with nonanastomotic strictures 17/19 versus 2/5 (P = 0.042). CONCLUSIONS: In our experience, endoscopic treatment of anastomotic biliary strictures is highly effective with a good long-term outcome. The presence of nonanastomotic and multiple strictures should be considered a factor associated with poor response to endoscopic management.  相似文献   
95.
The dissociation of renin and aldosterone during critical illness   总被引:3,自引:0,他引:3  
A syndrome of elevated PRA accompanied by inappropriately low plasma aldosterone (ALDO) levels has been identified in some critically ill patients. To determine whether this phenomenon is due to a disturbance in factors that stimulate ALDO, we measured PRA, angiotensin II (AII), potassium (K+), and ACTH levels in 83 patients admitted to an intensive care unit. In 59 patients, PRA was greater than 2.0 ng/ml X h. Of these, 24 had an ALDO to PRA ratio (ALDO/PRA) below 2 (group I), and 35 had an ALDO/PRA ratio of 2 or more (group II). An ALDO/PRA ratio below 2 was deemed inappropriately low. Despite markedly elevated PRA [34 +/- 12 (+/- SE) ng/ml X h], the group I patients had inappropriately low ALDO levels (19 +/- 5 ng/dL). Patients in group II had significantly higher ALDO levels (48 +/- 6 ng/dL) despite lower PRA (9 +/- 1 ng/ml X h). AII levels were appropriately elevated in group I (39 +/- 26 pg/mL) and significantly greater (P less than 0.5) than those in group II. PRA correlated well with AII in both groups. There were no differences in plasma ACTH or K+ in these 2 groups, and plasma cortisol levels were similarly elevated in both groups of patients. Of 66 consecutively studied patients, 14 (21%) had inappropriate ALDO (group I). Mortality was significantly greater in group I (75%) than in group II (46%; P less than 0.001). In summary, a significant subset (21%) of seriously ill patients have inappropriately low ALDO levels despite elevated PRA. This dissociation is not due to an impairment of AII production or changes in plasma ACTH or K+. This phenomenon is associated with a higher mortality during critical illness. In light of evidence of decreased adrenal androgen secretion during severe illness, this dissociation of renin and aldosterone may represent an additional adrenal adaptation designed to promote cortisol production in critically ill patients.  相似文献   
96.
A patient with Prinzmetal angina and ST segment elevation in the anterior ECG leads became asymptomatic after a 50% left anterior descending coronary artery stenosis was bypassed. However, seven years later Prinzmetal angina recurred but with ST segment elevation in the inferior ECG leads. Although the coronary bypass graft had remained patent, the proximal and distal left anterior descending coronary artery was occluded. No significant stenosis was present in the right coronary artery. Perhexiline maleate controlled his symptoms but when the drug was stopped because of side effects an acute inferior myocardial infarction occurred.  相似文献   
97.
Of 95 consecutive patients with active variant angina who underwent ergonovine testing in the coronary care unit while off treatment, 24 (25%) developed serious ventricular arrhythmias: ventricular tachycardia in eight, bigeminy in seven, pairs in five, and frequent ventricular extrasystoles in four. Ergonovine-induced arrhythmias were observed more often in patients with anterior than inferior ST segment elevation (p less than 0.05). ST segment elevation was significantly higher (10.3 +/- 8.1 vs 3.1 +/- 2.1 mm) in patients who developed arrhythmias. All ventricular arrhythmias began within 3 minutes after the onset of ST segment elevation. The intravenous administration of nitroglycerin eliminated arrhythmias in 22 of 24 cases; in only two patients did ventricular arrhythmias develop after the administration of nitroglycerin. Serious ventricular arrhythmias were found during spontaneous variant angina attacks in 14 of 24 patients with ergonovine-induced arrhythmias compared to 16 of 71 patients without ergonovine-induced arrhythmias (p less than 0.001). We conclude that arrhythmias during ergonovine testing are most often caused by ischemia and not reperfusion. Patients with arrhythmias during ergonovine-induced attacks are more likely to have arrhythmias during spontaneous attacks.  相似文献   
98.
A Random Sample from Wales   总被引:1,自引:0,他引:1  
S ummary . The serum iron, iron binding capacity and transferrin saturation has been estimated in a random sample of the Welsh population. The results indicate that iron deficient erythropoiesis is not uncommon, being present in 22 per cent of women and 6 per cent of men. Iron deficiency has only a low correlation with haemoglobin concentration and it is commonly found in subjects with a normal haemoglobin concentration by conventional standards.  相似文献   
99.
Summary. A DNA-based method was developed to genotype donors for the human platelet antigens HPA-la and -1b. Sequence-specific primers (SSP) were used in the polymerase chain reaction (PCR) which allowed the HPA-la/la. -lb/lb and -la/lb genotypes to be determined by PCR alone, no second analytical stage was required. 10 donors were tested by PCR-SSP and the results were concordant with serological phenotyping and independent DNA analysis.  相似文献   
100.
Although more than thirty mammalian genomes have been sequenced to draft quality, very few of these include the Y chromosome. This has limited our understanding of the evolutionary dynamics of gene persistence and loss, our ability to identify conserved regulatory elements, as well our knowledge of the extent to which different types of selection act to maintain genes within this unique genomic environment. Here, we present the first MSY (male-specific region of the Y chromosome) sequences from two carnivores, the domestic dog and cat. By combining these with other available MSY data, our multiordinal comparison allows for the first accounting of levels of selection constraining the evolution of eutherian Y chromosomes. Despite gene gain and loss across the phylogeny, we show the eutherian ancestor retained a core set of 17 MSY genes, most being constrained by negative selection for nearly 100 million years. The X-degenerate and ampliconic gene classes are partitioned into distinct chromosomal domains in most mammals, but were radically restructured on the human lineage. We identified multiple conserved noncoding elements that potentially regulate eutherian MSY genes. The acquisition of novel ampliconic gene families was accompanied by signatures of positive selection and has differentially impacted the degeneration and expansion of MSY gene repertoires in different species.Y chromosomes have arisen independently in divergent evolutionary lineages across the eukaryotic tree of life (Rice 1996; Marin and Baker 1998; Liu et al. 2004; Graves 2006; Koerich et al. 2008; Carvalho et al. 2009; Kaiser and Bachtrog 2010). While many genes are known to be Y-linked, the actual number of Y chromosomes that have been sequenced is extremely small (Skaletsky et al. 2003; Hughes et al. 2005; Kuroki et al. 2006; Clark et al. 2007; Koerich et al. 2008; Carvalho et al. 2009; Hughes et al. 2010, 2012) in relation to the rapid rate at which whole genomes are presently being sequenced. This reduced emphasis on sequencing Y chromosomes can be primarily attributed to their presumed low gene content and large amounts of repetitive DNA, that is often arrayed into long stretches of nearly identical sequence which precludes the use of shotgun sequencing approaches to assemble Y chromosome sequence into large, contiguous scaffolds. These assembly problems are further exacerbated when applying short-read next-generation sequence methods (Alkan et al. 2011).The most completely sequenced and annotated Y chromosomes are from three recently diverged catarrhine primates: human, chimpanzee, and rhesus macaque (Skaletsky et al. 2003; Hughes et al. 2005, 2010, 2012; Kuroki et al. 2006 ). Comparisons between these species offer an important glimpse into the immense structural variation and complexity that can emerge on the Y within a very short period of evolutionary time. However, these three primate species last shared a common ancestor ∼21 million years ago (Mya) (Meredith et al. 2011) and thus offer limited comparative breadth to discriminate characteristics present across most mammalian Y chromosomes from idiosyncratic features reflective of a small evolutionary sample. This lack of phylogenetic scope has (1) hampered identification of the ancestral properties of eutherian Y chromosomes, (2) obscured broader patterns of evolutionary constraint and selection in a nonrecombining environment, and (3) hidden the frequency with which novel genes arise and/or acquire new functions in species with diverse phenotypes and reproductive strategies.To expand our knowledge of eutherian Y chromosome structure and gene function, we generated the first extensive MSY (male-specific Y chromosome) sequence from two members of the Carnivora: the domestic cat, Felis silvestris catus, and domestic dog, Canis lupus familiaris. These two carnivore genomes provide a phylogenetically distinct vantage point with which to interpret the evolutionary patterns observed in the primate MSY comparisons, diverging from each other ∼55 Mya, and from primates ∼92 Mya (Meredith et al. 2011). Our combined analysis of two carnivore and three primate MSY sequences, together with physical mapping and functional sequence data from the mouse MSY, represent the first multiordinal comparison assessing deeper levels of evolutionary constraint. We also present a complete analysis of patterns of negative and positive selection to assess their effects on MSY degeneration and expansion.  相似文献   
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