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81.
The aim of the present study was to evaluate the characteristics of GH deficiency (GHD) in adult patients after neurosurgery for pituitary adenomas and craniopharingiomas. One hundred and one GHD patients, (42 F/59 M), aged 47.58+/-14.4 yr (mean+/-SD; range 21-78), body mass index (BMI) 28.6+/-0.6, with a history of adult-onset hypothalamic-pituitary disease, were recruited for the study. The whole group included: 45 non-functioning pituitary adenomas, 23 craniopharyngiomas, 16 PRLomas, 8 GHomas, 7 ACTHomas and 2 FSHomas; in particular 51 were macroadenomas and 27 microadenomas. At study entry, GHD diagnosis was carried out by assessing GH secretion after GHRH+arginine. All patients were submitted to the study at least 12 months after neurosurgery and, where needed, subjects were replaced with an appropriate treatment. GHD was mild in 3/101 (3%) and severe in 98/101 patients (97%). Other hormone deficiencies associated with GHD were considered: TSH, ACTH, FSH/LH, ADH. The distribution of peak GH among all patients, according to the type of disease before neurosurgery, showed that patients with Cushing disease were characterized by the presence of higher peak GH. According to the number of additional hormone deficits, the distribution of peak GH among all patients was as follows: GHD was isolated in 4/101 subjects (4%; group A), while it was associated with 1 (14/101, 14%; group B), 2 (22/101, 22%; group C), 3 (44/101, 43%; group D) and 4 hormone deficits (17/101, 16%; group E). GHD was severe in all patients in the panhypopituitaric group. Total IGF-I plasma levels in the whole group of GHD patients were 95.2+/-4.2 microg/l. In all groups of patients IGF-I was lower in subjects with severe GHD than in those with mild GHD (93.6+/-4.1 vs 148.6+/-33.6 microg/l, p<0.03). In particular, according to the type of disease presented before neurosurgery, patients with Cushing disease were characterized by the presence of higher IGF-I plasma levels compared to the other. According to the number of additional deficits, the distribution of IGF-I plasma levels was characterized by higher values when GHD was isolated than when it was associated with multiple hormone deficiencies. IGF-I plasma levels were positively associated to peak GH during GHRH+arginine (r=0.4, p<0.0005). We conclude that patients after neurosurgery approach for sellar and parasellar neoplasia, within an appropriate clinical context, and both the presence of additional pituitary hormone deficiency and low levels of IGF-I can be considered a clear GHD condition, and therefore do not require provocative tests evaluating GH secretion.  相似文献   
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83.
In order to determine the efficiency of Imugard IG500 filters in producing leukocyte-poor blood (LPB), 109 units of red cell concentrates were processed using cold (4 degrees C) or room temperature saline solution without the application of pressure to the blood bag. The results obtained in terms of red blood cell recovery, white blood cell removal, residual white blood cells, and free hemoglobin in the supernatant of the filtered units are comparable to those processed with the IBM 2991. LPB processed without pressure application to the blood bag and room temperature saline solution can be rapidly, efficiently and safely prepared in any size blood bank/transfusion service. This technique is definitely cost-saving in terms of equipment, software, space and personnel training.  相似文献   
84.
Aims/hypothesis Impaired insulin secretion has a strong genetic component. In this study we investigated whether the 12Glu9 polymorphism in the gene encoding the 2B-adrenergic receptor (ADRA2B) is associated with insulin secretion and/or the incidence of Type 2 diabetes in individuals with impaired glucose tolerance.Methods We investigated a total of 506 subjects with impaired glucose tolerance participating in the Finnish Diabetes Prevention Study (DPS). Participants were randomly assigned to an intervention group or a control group. Anthropometric measurements and an oral glucose tolerance test were performed at baseline and at annual follow-up. In a subgroup of patients (n=83), a frequently sampled intravenous glucose tolerance test (FSIGT) was performed at baseline.Results All patients had similar anthropometric measurements and insulin and glucose levels at baseline. Multiple logistic regression analysis revealed significant interaction (p=0.003) between study group and genotype across the entire study population. In the control group, subjects with the Glu9 allele had an increased risk of developing Type 2 diabetes compared with subjects with the Glu12/12 genotype (odds ratio [OR]=2.68, 95% CI 1.02–7.09, p=0.047 for Glu12/12, and OR=5.17, 95% CI 1.76–15.21, p=0.003 for Glu9/9). This increased risk was not observed in the intervention group, who showed significant weight loss during the trial. In the subgroup who underwent the FSIGT, subjects with the Glu9/9 genotype showed the lowest acute insulin response (p=0.005 for trend).Conclusions/interpretation The 12Glu9 polymorphism of ADRA2B is associated with impaired first-phase insulin secretion and may predict the development of Type 2 diabetes in subjects with impaired glucose tolerance who are not subjected to a lifestyle intervention.Abbreviations AIR acute insulin response - AR adrenergic receptor - BMR basal metabolic rate - DI disposition index - DPS the Finnish Diabetes Prevention Study - FSIGT frequently sampled intravenous glucose tolerance test - OR odds ratio - SG glucose effectiveness - SI insulin sensitivity index  相似文献   
85.
The objective of this study was to investigate the relationship between growth hormone (GH) dynamic tests (thyrotropin-releasing hormone [TRH] test and oral glucose tolerance test [OGTT]), insulin-like growth factor-I (IGF-I) plasma values, tumor size, and clinical outcome in patients with GH-secreting pituitary adenomas. Furthermore, we investigated the potential prognostic utility of the above biochemical parameters in the follow-up of patients with acromegaly. We studied 50 acromegalic patients (18 males and 32 females; mean age, 40 years; range, 16 to 69) who underwent trans-sphenoidal removal of a GH-secreting pituitary adenoma from 1990 to 1994. Preoperatively, we evaluated (1) GH plasmatic levels after an oral glucose load (OGTT) (blood samples were drawn at -15, 0, 30, 60, 90, 120, 150, and 180 minutes after oral administration of 0.75 g/kg body weight [BW] of glucose), (2) GH plasma levels after a TRH test (200 microg as an intravenous [IV] bolus), and (3) basal IGF-I plasma levels after an overnight fast. From 3 to 12 months after surgery we evaluated (1) GH plasma values after an OGTT, and (2) basal plasma IGF-I, free triiodothyronine (FT(3)), free thyroxine (FT(4)), thyroid-stimulating hormone (TSH), and urinary free cortisol. The same tests were performed every year for 5 years. All of the patients were classified into 4 subgroups according to the system of Hardy and Vezina. Preoperatively, "controlled" patients (n = 29) had a GH paradoxical response to TRH (n = 28) and an unresponsiveness to OGTT (n = 29); 23 of them belonged to the I and II classes. Only 5 poorly controlled patients (n = 21) showed a preoperative paradoxical response to TRH and 9 had a preoperative GH partial inhibition after OGTT; 19 of them belonged to the III and IV classes. Our data suggest that in the preoperative period in acromegalic patients the simultaneous presence of a GH paradoxical response to TRH and lack of GH inhibition after OGTT is inversely related to the tumor size and therefore more likely to be restored to normal by surgical treatment.  相似文献   
86.
OBJECTIVE: A relationship between hyperinsulinemia and decreased serum sex hormone-binding globulin (SHBG) has been described in adults. We evaluated the usefulness of SHBG as an index of hyperinsulinemia and/or insulin resistance in obese children (aged 6-9 years) of both sexes and its possible influence on the androgenic status. DESIGN: We carried out a cross-sectional study of cases and controls. We studied 61 obese children (22 males, 39 females) with body mass index (BMI) superior to the 90(th) percentile and a control group of age- and sex-matched non-obese children. We measured serum glucose, insulin, TSH, free thyroxine, 17beta-estradiol, testosterone and SHBG. Also, we correlated these parameters with anthropometric measures. RESULTS: The obese group presented significantly elevated levels of insulin (P=0.001) and insulin/glucose ratio (P=0.0012) compared with the control group. SHBG (P=0.0001) and testosterone (P=0.0169) levels were significantly lower than those in the non-obese group. We did not find any difference in the free androgen index (FAI). Fasting insulin (r=-0.4512; P<0.001), BMI (r=-0.3185; P<0.05) and testosterone (r=-0.3705; P<0.01) were inversely correlated with SHBG concentration. According to multivariate analyses, insulin was the only independent predictor factor for serum SHBG concentration in the obese group (r partial=0.1280; P=0.0171). CONCLUSIONS: In summary, at this age there is a strong relationship between insulin and SHBG. The changes in SHBG levels of the obese group did not affect FAI and, therefore, they did not cause changes in the androgenic status. Our data support the role of insulin in the regulation of serum SHBG levels.  相似文献   
87.
Abstract An improved method of inducing diabetes in dogs was developed. This method included 90% pancreatectomy, 2 mg/kg streptozotocin (STZ) perfused into pancreaticoduodenal artery, and the fixation suture of the duodenum to the costo-abdominal wall. Vasopressin injection administered to the animals before surgery reduced bleeding. All dogs used in this procedure survived and became diabetic. One month after the procedure the pancreatic islets were reduced in volume and the number compared with pancreas tissue obtained during the surgery. Acinar tissue remained with a normal histology, and exocrine function maintained the physiological parameters, except for a soft faecal consistency. We conclude that this procedure is effective in inducing experimental diabetes in dogs.  相似文献   
88.
BackgroundRecurrent respiratory papillomatosis (RRP) is a respiratory tract disease that affects children and adults and is characterized by the recurrent proliferation of multiple papillomas. The etiologic agent is the human papillomavirus, mainly genotypes 6 and 11. Furthermore, polymorphisms in TAP1 appear to influence the selection of antigenic peptides and the transport process to the rough endoplasmic reticulum, for their subsequent presentation to T lymphocytes, an essential process against viral diseases and tumor processes. Previous studies have shown that individuals with those polymorphisms are susceptible to immune, infectious, and tumor‐related diseases. The present study aimed to determine the association between the TAP1 rs1057141 (c.1177A>G) and rs1135216 (c.2090A>G) single nucleotide polymorphisms (SNPs) and RRP.MethodsA case–control study was carried out on a group of 70 individuals (35 controls and 35 patients). RRP diagnosis, HPV genotyping, and viral load were determined through histology and PCR. SNPs rs1057141 and rs1135216 were identified through allelic discrimination, using real‐time PCR. The haplotypic analyses were performed using the Arlequin 3.5 program.ResultsHPV‐6 and HPV‐11 were the genotypes found in the samples. In the polymorphism analysis, rs1057141 showed no significant differences (p = 0.049, CI = 0.994–7.331). In contrast, a significant difference was found in rs1135216 (p = 0.039, OR = 2.4) in the allelic analysis, as well as in the dominant (p = 0.027, OR = 3.06), codominant (p = 0.033, OR = 3.06), and additive model (p = 0.043, OR = 2.505) in subjects with the G allele.ConclusionThe G allele in rs1135216 was associated with a genetic risk of susceptibility for RRP in a population in Western Mexico.  相似文献   
89.
90.
The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS‐Cov‐2) has led to the elaboration of multiple studies to increase knowledge and understanding, hence, having the ability to accomplish an adequate and timely diagnosis and give an optimal treatment according to the patient's condition. The clinical manifestations of COVID‐19 pose a series of challenges both in understanding and delimiting the disease secondary to the SARS‐CoV‐2 infection. This is due to the fact that the main axis of this disease is the endothelial compromise and the production of a “cytokine storm,” triggering multiple organ failure and death. Given that a complete understanding of its pathophysiology and clinical behavior has not yet been achieved, we wondered if coinfection with other respiratory viruses modifies its performance and outcomes described so far. A literature search was performed, obtaining 68 articles, of which 25 were analyzed. The analysis showed us that there is a high variety both in the types of associated infections and in the clinical behavior of patients and their outcomes. Therefore, we consider that the search for other infections should be performed exhaustively, especially in those cases that may be susceptible to treatment such as Influenza A, human immunodeficiency virus, or bacterial infections. As well as optimize the analysis of these cases and establish if there are characteristics that allow establishing the possibility of carrying an additional infection to that of SARS‐CoV‐2 and the implications for the management and prognosis of the patient.  相似文献   
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