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991.
We assessed the maturity of the lungs and the radial count in 10 infants with congenital diaphragmatic hernia who died in the immediate perinatal period. The lungs were all immature, with a histologic appearance of less than stated gestational age. The ipsilateral lungs were less mature in appearance than were the contralateral ones. The radial count, an assessment of acinar complexity, was reduced in all cases, and once again the ipsilateral lung was more affected. We present evidence that, in 4 of 6 lungs, volumes were more reduced than predicted from the radial count, and this may be due to loss of (airway) units. We have discussed the controversy about the appearance of the acinus in diaphragmatic hernia and present reasons to explain this. Hyaline membrane disease often occurs in diaphragmatic hernia, even at full term. Intra-alveolar hemorrhage is a common complication of diaphragmatic hernia.  相似文献   
992.
Short stature in man may result from a deficiency of GH or insulin-like growth factors (IGFs). In African pygmies and other individuals with the pygmy trait, serum GH and IGF-II are similar to levels in taller subjects, but serum IGF-I levels are low. To determine whether another population with comparably short stature has similar or related defects, we studied the Mountain Ok population of Papua New Guinea. The mean height of adult men was 152 +/- 6.0 (+/- SD) cm (n = 141), and that of women was 146 +/- 5.7 cm (n = 150). Serum GH and IGF-II concentrations were in the normal (U.S.) range in the Mountain Ok subjects. In the men, serum IGF-I values were also normal, thereby distinguishing the endocrine profile associated with short stature in these subjects from that in African pygmies. Serum IGF-I was not measured in any Mountain Ok women. Since marginal dietary protein is characteristic of the traditional Papua New Guinea diet, we determined serum albumin and prealbumin concentrations in the Mountain Ok subjects. The serum proteins were in the normal (U.S.) range (30-50 g/L for albumin; 10-40 mg/dL for prealbumin), indicating that chronic or acute malnutrition was unlikely in these subjects. Taken together, these findings indicate that short stature in the Mountain Ok people of Papua New Guinea is associated with normal serum GH, IGF-I, IGF-II, and protein levels and indicate that other factors determine stature in some populations with short stature.  相似文献   
993.
HIV remains concentrated among men who have sex with men (MSM) in Peru, and homophobia and AIDS-related stigmas have kept the epidemic difficult to address. Gay self-identity has been associated with increased HIV testing, though this relationship has not been examined extensively. Social media use has been rapidly increasing in Peru, yet little is known about MSM social media users in Peru. This study sought to investigate the demographic, behavioral, and stigma-related factors associated with HIV testing among social media-using Peruvian MSM. Five hundred and fifty-six MSM from Lima and surrounding areas were recruited from social networking websites to complete a survey on their sexual risk behaviors. We examined the demographic and social correlates of HIV testing behavior among this sample. Younger age and non-gay identity were significantly associated with lower likelihood of getting tested in univariate analysis. After controlling for key behaviors and AIDS-related stigma, younger age remained significantly associated with decreased testing. Participants who engaged in discussions online about HIV testing were more likely to get tested, while AIDS-related stigma presented a significant barrier to testing. Stigma severity also varied significantly by sexual identity. Youth appear to be significantly less likely than older individuals to test for HIV. Among Peruvian MSM, AIDS-related stigma remains a strong predictor of willingness to get tested. Social media-based intervention work targeting Peruvian youth should encourage discussion around HIV testing, and must also address AIDS-related stigma.  相似文献   
994.

Background

Although prior studies have examined BMI trajectories in Western populations, little is known regarding how BMI trajectories in Asian populations vary between adults with and without diabetes.

Objective

To examine how BMI trajectories vary between those developing and not developing diabetes over 18 years in an Asian cohort.

Design

Multilevel modeling was used to depict levels and rates of change in BMI for up to 18 years for participants with and without self-reported physician-diagnosed diabetes.

Participants

We used 14,490 data points available from repeated measurements of 3776 participants aged 50+ at baseline without diabetes from a nationally representative survey of the Taiwan Longitudinal Study on Aging (TLSA1989-2007).

Main Measures

We defined development of diabetes as participants who first reported diabetes diagnoses in 2007 but had no diabetes diagnoses at baseline. We defined the reference group as those participants who reported the absence of diabetes at baseline and during the entire follow-up period.

Key Results

When adjusted for time-varying comorbidities and behavioral factors, higher level and constant increases in BMI were present more than 6.5 years before self-reported diabetes diagnosis. The higher BMI level associating with the development of diabetes was especially evident in females. Within 6.5 years prior to self-reported diagnosis, however, a wider range of decreases in BMI occurred (βdiabetes?=?1.294, P?=?0.0064; βdiabetes*time?=?0.150, P?=?0.0327; βdiabetes*time 2?=??0.008, P?=?0.0065). The faster rate of increases in BMI followed by a greater decline was especially prominent in males and individuals with BMI ≧24.

Conclusions

An unintentional decrease in BMI in sharp contrast to the gradually rising BMI preceding that time may be an alarm for undiagnosed diabetes or a precursor to developing diabetes.
  相似文献   
995.
OBJECTIVE: Thyroxine-binding globulin (TBG) encoded by the TBG gene on chromosome Xq22 is the major transport protein, carrying approximately 75% of circulating T4. Inherited defects in TBG are associated with three phenotypes based on the level of TBG in serum of affected hemizygous males: complete TBG deficiency (TBG-CD), partial TBG deficiency (TBG-PD) and TBG excess (TBG-E). In this study, we report two unrelated Han Chinese males with complete TBG deficiency who carry different mutations in the TBG gene. PATIENTS: Two index cases of Han males who were diagnosed as having TBG deficiency on the basis of undetectable serum TBG and an additional 75 (50 males and 25 females) normal Han Chinese. MEASUREMENT: Serum thyroid hormones were measured by chemiluminescent immunoassay, thyroid autoantibodies by an agglutination test, and TSH receptor antibody and TBG by radioimmunoassay. Genomic DNA extraction, polymerase chain reaction (PCR) and DNA sequence analysis of the TBG gene were performed with standard methods. RESULTS: One index case had one missense mutation in his copy of the gene, a G --> A transition in codon 52 that results in the replacement of serine by asparagine, and a known polymorphism in codon 283 (TTG --> TTt) that results in the replacement of leucine by phenylalanine. The allelic frequency of TBG-Poly allele in 75 normal Han Chinese (100 chromosomes) was 31%. A second index case was hemizygous for a nonsense mutation in codon 280 of exon 3 (TGG --> TGa). This mutation, located in the C-terminal of TBG, predicts a markedly truncated protein. CONCLUSIONS: This is the first report of complete thyroxine-binding globulin deficiency (TBG-CDT1 and TBG-CDT2) due to TBG gene mutations in Taiwan.  相似文献   
996.
997.
998.
BACKGROUND/AIMS: Visceral and renal arteries pseudoaneurysms are uncommon but potentially lethal complications of hepatic and pancreatobiliary interventions. To evaluate the clinical outcome of transcatheter arterial coils embolotherapy, we reviewed our institution's experience with the management for bleeding pseudoaneurysms. METHODOLOGY: From January 1988 through December 2004, 20 patients were encountered who developed massive bleeding from pseudoaneurysms following hepatobiliary and pancreatic interventions. All patients underwent diagnostic angiography and transarterial embolization was carried out thereafter. RESULTS: Embolization was technically successful without major post-procedural complications in all patients. Bleeding was stopped after embolization in 17 patients (85%), and rebleeding did occur in one patient during the follow-up periods. Repeat coil embolotherapy was performed in one patient with recurrent bleeding, but they needed surgical intervention because of failed re-embolization. Another two patients needed surgical ligation and one of the patients died of sepsis two weeks later. CONCLUSIONS: An emergency angiography should be considered in all patients in whom pseudoaneurysm is suspected following hepatobiliary and pancreatic interventions. Transcatheter arterial coil embolization is a safe and effective treatment for pseudoaneurysm. Surgical intervention should be reserved for patients for whom embolization fails or for whom it is not possible.  相似文献   
999.
Diverticular disease of the small bowel   总被引:7,自引:0,他引:7  
BACKGROUND/AIMS: The clinical picture of small bowel diverticula has not been well-clarified because of its infrequent incidence and limited case number in most published reports. We evaluated a large series of small bowel diverticula and further compared the clinical picture of the diverticula at different parts of small bowel. METHODOLOGY: The medical records of 88 patients with diverticular disease of the small bowel were reviewed from 1979-1997. This study included all diverticula from duodenum to ileum. RESULTS: The most common small bowel diverticulum was duodenal diverticulum (45%), followed by Meckel's diverticulum (23%). The most common clinical presentation was abdominal pain (48.9%), followed by gastrointestinal bleeding (29.5%). However, among the Meckel's diverticula, gastrointestinal bleeding (60%) was the most common presentation. The accurate diagnostic rate for diverticula, overall, was 25.0%. Thirty-nine (44.3%) of the diverticula were found incidentally. Twenty-three cases (26.1%) were diagnosed by gastrointestinal barium study. Thirty-eight (42.1%) diverticula were left alone without any sequela, and the remaining 55 (56.8%) diverticula needed either bowel resection (30.7%) or diverticulectomy (26.1%). All of the Meckel's diverticula were treated by surgery. Postoperative complication occurred in 9 (10.3%) patients. Hospital mortality rate was 3.4%. CONCLUSIONS: Duodenal diverticulum was the most common small bowel diverticulum. Abdominal pain and gastrointestinal bleeding were the most common clinical presentations. The small bowel diverticula, except for Meckel's diverticulum, did not need to be treated if there were no significant symptoms.  相似文献   
1000.
Total body irradiation (TBI) is frequently used in hematopoietic stem cell transplantation (HSCT) and is associated with many complications due to radiation injury to the normal cells, including normal stem cells. Nevertheless, the effects of TBI on the mesenchymal stromal stem cell (MSC) are not fully understood. Bone marrow-derived MSCs (BM-MSCs) isolated from normal adults were irradiated with 200 cGy twice daily for consecutive 3 days, a regimen identical to that used in TBI-conditioning HSCT. The characteristics, differentiation potential, cytogenetics, hematopoiesis-supporting function, and carcinogenicity of the irradiated BM-MSCs were then compared to the non-irradiated control. The irradiated and non-irradiated MSCs shared similar morphology, phenotype, and hematopoiesis-supporting function. However, irradiated MSCs showed much lower proliferative and differentiative potential. Irradiation also induced clonal cytogenetic abnormalities of MSCs. Nevertheless, the carcinogenicity of irradiated MSCs is low in vitro and in vivo. In parallel with the ex vivo irradiation experiments, decreased proliferative and differentiative abilities and clonal cytogenetic abnormalities can also be found in MSCs isolated from transplant recipients who had received TBI-based conditioning previously. Thus, TBI used in HSCT drastically injury MSCs and may contribute to the development of some long-term complications associated with clonal cytogenetic abnormality and poor adipogenesis and osteogenesis after TBI.  相似文献   
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