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131.
Prehensile tails are defined as having the ability to grasp objects and are commonly used as a fifth appendage during arboreal locomotion. Despite the independent evolution of tail prehensility in numerous mammalian genera, data relating muscle structure, physiology, and function of prehensile tails are largely incomplete. Didelphid marsupials make an excellent model to relate myosin heavy chain (MHC) isoform fiber type with structure/function of caudal muscles, as all opossums have a prehensile tail and tail use varies between arboreal and terrestrial forms. Expanding on our previous work in the Virginia opossum, this study tests the hypothesis that arboreal and terrestrial opossums differentially express faster versus slower MHC isoforms, respectively. MHC isoform expression and percent fiber type distribution were determined in the flexor caudae longus (FCL) muscle of Caluromys derbianus (arboreal) and Monodelphis domestica (terrestrial), using a combination of gel electrophoresis and immunohistochemistry analyses. C. derbianus expresses three MHC isoforms (1, 2A, 2X) that are distributed (mean percentage) as 8.2% MHC‐1, 2.6% 1/2A, and 89.2% 2A/X hybrid fibers. M. domestica also expresses MHC‐1, 2A, and 2X, in addition to the 2B isoform, distributed as 17.0% MHC‐1, 1.3% 1/2A, 9.0% 2A, 75.2% 2A/X, and 0.3% 2X/B hybrid fibers. The distribution of similar isoform fiber types differed significantly between species (P < 0.001). Although not statistically significant, C. derbianus was observed to have larger cross‐sectional area (CSA) for each corresponding fiber type along with a greater amount of extra‐cellular matrix. An overall faster fiber type composition (and larger fibers) in the tail of an arboreal specialist supports our hypothesis, and correlates with higher muscle force required for tail hanging and arboreal maneuvering on terminal substrates. Conversely, a broader distribution of highly oxidative fibers in the caudal musculature is well suited for tail nest building/remodeling behaviors of terrestrial opossums. Anat Rec, 297:1364–1376, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
132.
Haplogroup J1 is a prevalent Y-chromosome lineage within the Near East. We report the frequency and YSTR diversity data for its major sub-clade (J1e). The overall expansion time estimated from 453 chromosomes is 10 000 years. Moreover, the previously described J1 (DYS388=13) chromosomes, frequently found in the Caucasus and eastern Anatolian populations, were ancestral to J1e and displayed an expansion time of 9000 years. For J1e, the Zagros/Taurus mountain region displays the highest haplotype diversity, although the J1e frequency increases toward the peripheral Arabian Peninsula. The southerly pattern of decreasing expansion time estimates is consistent with the serial drift and founder effect processes. The first such migration is predicted to have occurred at the onset of the Neolithic, and accordingly J1e parallels the establishment of rain-fed agriculture and semi-nomadic herders throughout the Fertile Crescent. Subsequently, J1e lineages might have been involved in episodes of the expansion of pastoralists into arid habitats coinciding with the spread of Arabic and other Semitic-speaking populations.  相似文献   
133.
This report aims to genetically characterize the relationships between geographically targeted human populations covering an expanse from east sub-Saharan Africa northeastward into northern India with an emphasis on the Near East. A number of parameters of population genetics interest were examined based on allele frequencies from 15 forensic autosomal STR markers [D8S1179, D21S11, D7S820, CSF1PO, D3S1358, TH01, D13S317, D16S539, D2S1338, D19S433, vWA, TPOX, D18S51, D5S818, and FGA]. The phylogenetic analyses generated from genetic profiles of 885 individuals indicate that populations west of and including Iran have experienced substantial gene flow. Accordingly, our findings delineate a region of genetic homogeneity concentrated within the Near East with increasing genetic differentiation moving south into Africa and further east into Asia. We suggest that the Saharan desert, the Hindu Kush mountain range and perhaps to a lesser extent, the deserts of Iran may have acted as southern, eastern and northern geographical barriers, respectively, forming a genetic enclosure that allows limited gene flow outside the Near East. The biparental genetic landscape supports a picture of close contact between the Arab and Persian populations, perhaps beginning during the initial settlement of Asia from Africa extending to recent times.  相似文献   
134.
STUDY OBJECTIVES: Sleep bruxism is an involuntary mandibular movement with tooth grinding during sleep. The prevalence of sleep bruxism in children is high and may lead to frequent arousals with altered daytime functioning. We investigated the sleep architecture, the incidence of gastroesophageal reflux, and the daytime cognitive behavioral functioning in a group of children with sleep bruxism. DESIGN-PATIENTS: This prospective pilot study included 10 children. Polysomnographic data with pH-probe analysis was compared with 10 age- and sex-matched controls. Each patient completed a dental evaluation, a nighttime polysomnogram, and cognitive behavioral tests (Kaufman Brief Intelligence Test and Achenbach Child Behavior Checklist). RESULTS: Eight of 10 children had clinically significant bruxism and the 2 remaining patients had recent teeth exfoliation. There was no difference on sleep architecture between patients and controls, except for a higher arousal index for the bruxism group (36.7 vs 20.7, p < .007). Sleep bruxism occurred more frequently in stage 2 and rapid eye movement sleep, with arousals in 66% of the cases. There was no relationship of bruxism to gastroesophageal reflux or intelligence. However, 40% of the patients had elevated scores on the Achenbach Child Behavior Checklist, indicating significant attention and behavior problems, and there were moderate correlations between the arousal index and several of the behavior-problem scales from the Achenbach Child Behavior Checklist (0.5 to 0.6). CONCLUSIONS: The data suggest that children with bruxism have a higher arousal index, which may be associated with an increased incidence of attention-behavior problems. Future studies investigating pediatric sleep bruxism will need to focus on behavior issues that may be prevalent in this population.  相似文献   
135.

Background  

Low back pain and its associated incapacitating effects constitute an important healthcare and socioeconomic problem, as well as being one of the main causes of disability among adults of working age. The prevalence of non-specific low back pain is very high among the general population, and 60–70% of adults are believed to have suffered this problem at some time. Nevertheless, few randomised clinical trials have been made of the efficacy and efficiency of acupuncture with respect to acute low back pain. The present study is intended to assess the efficacy of acupuncture for acute low back pain in terms of the improvement reported on the Roland Morris Questionnaire (RMQ) on low back pain incapacity, to estimate the specific and non-specific effects produced by the technique, and to carry out a cost-effectiveness analysis.  相似文献   
136.
Computarized tomography allows proper identification and evaluation of stage in the majority patients with periampullary tumors. However, 30% of peritoneal metastases cannot be seen in image studies. The aim of the present study was to evaluate the role of laparoscopy with laparoscopic ultrasound in the staging process of pancreatic and ampullary tumor. Diagnostic laparoscopy was performed on 20 patients included in the study Mean age was 58.35 +/- 13.4 years. Twelve were males and eight females. In two patients, laparoscopy showed peritoneal metastases and ultrasound did not show extrapancreatic involvement. In five patients, there was vascular invasion without metastases. In three patients, both peritoneal metastases and vascular invasion were found, and in five there was neither vascular invasion nor metastasis. Laparoscopic findings were confirmed in a but one patient. In 14 of the 16 patients In whom peritoneal lavage was performed, microscopic exam showed a sufficient number of cells to make a diagnosis. We concluded that laparoscopy with ultrasound is useful in staging of patients with duodeno-bilio-pancreatic malignancies.  相似文献   
137.

Introduction:

Preeclampsia is the most important cause of maternal mortality in developing countries. A comprehensive prenatal care program including bio-psychosocial components was developed and introduced at a national level in Colombia. We report on the trends in maternal mortality rates and their related causes before and after implementation of this program.

Methods:

General and specific maternal mortality rates were monitored for nine years (1998-2006). An interrupted time-series analysis was performed with monthly data on cases of maternal mortality that compared trends and changes in national mortality rates and the impact of these changes attributable to the introduction of a bio-psychosocial model. Multivariate analyses were performed to evaluate correlations between the interventions.

Results:

Five years after (2002 - 2006) its introduction the general maternal mortality rate was significantly reduced to 23% (OR=0.77, CI 95% 0.71-0.82).The implementation of BPSM also reduced the incidence of preeclampsia in 22% (OR= 0.78, CI 95% 0.67-0.88), as also the labor complications by hemorrhage in 25% (OR=0.75, CI 95% 0.59-0.90) associated with the implementation of red code. The other causes of maternal mortality did not reveal significant changes. Biomedical, nutritional, psychosocial assessments, and other individual interventions in prenatal care were not correlated to maternal mortality (p= 0.112); however, together as a model we observed a significant association (p= 0.042).

Conclusions:

General maternal mortality was reduced after the implementation of a comprehensive national prenatal care program. Is important the evaluation of this program in others populations.  相似文献   
138.
This report is of a community-based case control study to assess whether the severity of acute diarrhea by rotavirus (RV) in young children is associated with a particular VP7 (G) or VP4 (P) RV serotype. Five hundred twenty children younger than 2 years of age with diarrhea lasting less than 3 days were age and gender matched with 520 children with no diarrhea. The G and P serotypes were determined with specific monoclonal antibodies, and the VP4 serotype specificity in a subgroup was confirmed by genotyping. Infection with a G3 serotype led to a higher risk of diarrhea than infection with a G1 serotype. Infection with a G3-nontypeable-P serotype was associated with more severe gastroenteritis than infection with a G3 (or G1) P1A[8] serotype. A child with diarrhea-associated dehydration was almost five times more likely to be infected with a G3-nontypeable-P serotype than a child without dehydration (P < 0.001). Moreover, the two predominant monotypes within serotype P1A[8] had significantly different clinical manifestations. In this study, the severity of RV-associated diarrhea was related to different P serotypes rather than to G serotypes. The relationship between serotype and clinical outcomes seems to be complex and to vary among different geographic areas.  相似文献   
139.
Single-cell resolution cytokine ELISPOT assays are increasingly used to gain insights into clonal sizes of type 1 and type 2 effector T cell populations in vivo. However, ELISPOT assays permitting monitoring of regulatory IL-10-producing T cells have so far not been established. Unlike IFN-gamma, IL-2, IL-4, and IL-5 assays performed on PBMC in which the recall antigen-induced cytokine spots are T cell-derived, we show here that in such assays IL-10 is primarily monocyte-derived. T cell-derived IL-10 spots were 80 x 10(3) microm(2) in size, seven times larger than spots produced by monocytes, and B cells produced even smaller spots. Based on spot size gating and the use of B cells as APC, we have established test conditions that permit measurement of cognate IL-10 production by low-frequency antigen-specific T cells. IL-10-producing PPD-specific CD4(+) T cells were detected in frequencies comparable to IFN-gamma-secreting CD4(+) T cells in tuberculosis patients, but not in uninfected healthy control individuals. In contrast, IL-10-secreting CD4(+) T cells specific for a panel of recall antigens could not be detected in frequencies >1/100,000 in healthy individuals whose CD4(+) cells responded to these antigens with type 1 or type 2 cytokine production in the 1:100,000-1:1000 frequency range. Therefore, the induction of IL-10-producing T cells seems to be under tighter control than that of Th1/Th2 cells, apparently confined to states of chronic immune stimulation. Access to low-frequency immune monitoring of IL-10-producing T cells will provide new insights into the role of regulatory T cells in health and disease.  相似文献   
140.
Vasopressin regulates human water homeostasis by re‐distributing homotetrameric aquaporin‐2 (AQP2) water channels from intracellular vesicles to the apical membrane of renal principal cells, a process in which phosphorylation of AQP2 at S256 by cAMP‐dependent protein kinase A (PKA) is thought to be essential. Dominant nephrogenic diabetes insipidus (NDI), a disease in which the kidney is unable to concentrate urine in response to vasopressin, is caused by AQP2 gene mutations. Here, we investigated a reported patient case of dominant NDI caused by a novel p.R254Q mutation. Expressed in oocytes, AQP2‐p.R254Q appeared to be a functional water channel, but was impaired in its transport to the cell surface to the same degree as AQP2‐p.S256A, which mimics non‐phosphorylated AQP2. In polarized MDCK cells, AQP2‐p.R254Q was retained and was distributed similarly to that of unstimulated wt‐AQP2 or AQP2‐p.S256A. Upon co‐expression, AQP2‐p.R254Q interacted with, and retained wt‐AQP2 in intracellular vesicles. In contrast to wild‐type AQP2, forskolin did not increase AQP2‐p.R254Q phosphorylation at S256 or its translocation to the apical membrane. Mimicking constitutive phosphorylation in AQP2‐p.R254Q with the p.S256D mutation, however, rescued its apical membrane expression. These date indicate that a lack of S256 phosphorylation is the sole cause of dominant NDI here, and thereby, p.R254Q is a loss of function instead of a gain of function mutation in dominant NDI. © 2009 Wiley‐Liss, Inc.  相似文献   
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