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91.
We identified a previously uncharacterized gene, spermatid maturation 1 (Spem1), encoding a protein exclusively expressed in the cytoplasm of steps 14-16 elongated spermatids in the mouse testis. This protein contains no known functional domains and is highly conserved across mammalian species. Male mice deficient in Spem1 were completely infertile because of deformed sperm characterized by a bent head wrapped around by the neck and the middle piece of the tail. We show that lack of Spem1 causes failure of the cytoplasm to become loose and detach from the head and the neck region of the developing spermatozoa. Retained cytoplasmic components mechanically obstruct the straightening of the sperm head and the stretching of the growing tail, leading to the bending of the head in the neck, followed by the wrapping of the head by the neck or the middle piece of the sperm tail. Our study reveals that proper cytoplasm removal is a genetically regulated process requiring the participation of Spem1 and that lack of Spem1 causes sperm deformation and male infertility.  相似文献   
92.
Between June 1989 and June 1992, 144 patients participated in sequential clinical trials using peripheral blood progenitor cells (PBC) as their sole source of hematopoietic rescue following high-dose chemotherapy. All patients had received prior extensive combination chemotherapy and had marrow defects that precluded autologous bone marrow transplantation (ABMT). PBC were collected according to a single apheresis protocol. The initial 86 patients (group 1) had PBC collected without mobilization. Beginning in April 1991, PBC were mobilized solely with recombinant human granulocyte-macrophage colony-stimulating factor (rHuGM-CSF). Thirty-four patients (group 2) received rHuGM-CSF at a dose of 125 micrograms/m2/d by continuous intravenous infusion, and 24 patients (group 3) received rHuGM-CSF at a dose of 250 micrograms/m2/d by continuous intravenous infusion. Patients underwent at least six aphereses and had a minimum of 6.5 x 10(8) mononuclear cells (MNC)/kg collected. Cytokines were not routinely administered immediately after transplantation. A median of nine aphereses were required to collect PBC in group 1 and seven aphereses for groups 2 and 3 (P = .03). The time required to recover 0.5 x 10(9)/L granulocytes after transplant was significantly shorter (P = .0004) for the mobilized groups; the median time to recovery was 26 days for group 1, 23 days for group 2, and 18 days for group 3. Transplantation of PBC mobilized with rHuGM-CSF resulted in a shorter time to platelet (P = .04) and red blood cell (P = .01) transfusion independence. Mobilization with rHuGM-CSF alone resulted in efficient collection of PBC, that provided rapid and sustained restoration of hematopoietic function following high-dose chemotherapy. Mobilization of PBC with rHuGM-CSF alone is an effective method for patients who have received prior chemotherapy and have bone marrow abnormalities.  相似文献   
93.
Bentz  M; Cabot  G; Moos  M; Speicher  MR; Ganser  A; Lichter  P; Dohner  H 《Blood》1994,83(7):1922-1928
The presence of BCR-ABL fusion genes has important diagnostic and prognostic implications in chronic myeloid leukemia (CML) and acute lymphoblastic leukemia (ALL). The CML-specific chimeric BCR-ABL gene with a break involving the major breakpoint cluster region (M-bcr) of the BCR-gene has been detected by means of fluorescence in situ hybridization (FISH). In this study, we present a FISH protocol that allows the detection of breaks in both the major and the minor breakpoint cluster region (m-bcr). Three hybridization signals of D107F9, a yeast artificial chromosome (YAC)-derived probe spanning the breakpoint regions of the BCR gene, were indicative of the translocation events. To increase the specificity further, this probe was combined with cos-abl 8, a cosmid probe flanking the breakpoint within the ABL gene for dual-color hybridization. Samples of 21 patients with CML, the ALL-derived cell line SUP-B15, and of seven patients with Philadelphia chromosome (Ph1)-positive ALL (three of them with breakpoints within m-bcr) were examined. BCR-ABL fusion was detected in all cases with high specificity (false-positive nuclei: mean, 0.1%). On cytogenetic preparations, the percentages of BCR-ABL- positive interphase cells ranged from 53% to 91%. Comparable efficiencies were achieved on blood smears. In conclusion, hybridization with D107F9 and cos-abl 8 allows unambiguous diagnosis of BCR-ABL genes and is likely to become an important tool for the monitoring of therapies in patients with CML and ALL.  相似文献   
94.
We report the treatment outcome of allogeneic bone marrow transplantation in ten patients with Philadelphia chromosome-positive acute lymphoblastic leukemia. Six patients are alive and well for 6 to 30 months (median 19 months) after transplantation. Four patients died with transplant related complications. In view of the poor prognosis associated with this disease, marrow ablation followed by allogeneic or syngeneic marrow grafting may be the preferred treatment modality if a suitable marrow donor is available.  相似文献   
95.
96.
Currently, there is confusion about the value of using nutritional support to treat malnutrition and improve functional outcomes in chronic obstructive pulmonary disease (COPD). This systematic review and meta‐analysis of randomized, controlled trials (RCT) aimed to clarify the effectiveness of nutritional support in improving functional outcomes in COPD. A systematic review identified 12 RCT (n = 448) in stable COPD patients investigating the effects of nutritional support (dietary advice (1 RCT), oral nutritional supplements (10 RCT), enteral tube feeding (1 RCT)) versus control on functional outcomes. Meta‐analysis of the changes induced by intervention found that while respiratory function (forced expiratory volume in 1 s, lung capacity, blood gases) was unresponsive to nutritional support, both inspiratory and expiratory muscle strength (maximal inspiratory mouth pressure +3.86 standard error (SE) 1.89 cm H2O, P = 0.041; maximal expiratory mouth pressure +11.85 SE 5.54 cm H2O, P = 0.032) and handgrip strength (+1.35 SE 0.69 kg, P = 0.05) were significantly improved and associated with weight gains of ≥2 kg. Nutritional support produced significant improvements in quality of life in some trials, although meta‐analysis was not possible. It also led to improved exercise performance and enhancement of exercise rehabilitation programmes. This systematic review and meta‐analysis demonstrates that nutritional support in COPD results in significant improvements in a number of clinically relevant functional outcomes, complementing a previous review showing improvements in nutritional intake and weight.  相似文献   
97.
Vaginal chronic graft‐versus‐host disease (cGVHD) is a common complication of stem cell transplantation. Human papillomavirus (HPV) disease can reactivate after transplantation, presumably because of immune factors affecting systemic immunity, such as waning antibody titers, impaired T‐ and B‐lymphocyte responses, and the use of immunosuppressive therapies. However, a relationship between the use of local immunosuppressive agents and HPV reactivation and spread has not been previously described, to our knowledge. A 30‐year‐old woman, 2 years post transplant receiving systemic cyclosporine for cGVHD, was treated with vaginal dilators, topical corticosteroids, and estrogen for vaginal cGVHD. Colposcopy and biopsy for abnormal cytology revealed condylomatous cervicitis. Over the next 4 months, while continuing dilator therapy, linear verrucous lesions developed in the vagina and vulva, and were successfully treated with laser therapy. Use of local immunosuppression and dilators for genital GVHD can enhance spread of HPV infection. Integration of HPV screening and treatment into the care of women with genital cGVHD and development of strategies to manage both conditions simultaneously are warranted.  相似文献   
98.
OBJECTIVE: To determine the role of hyperglycemia in prospective analyses of peripheral vascular disease (PVD) in type 2 diabetes, taking into account other potential risk factors. RESEARCH DESIGN AND METHODS: Potential risk factors for the development of PVD were examined in 3,834 of 5,102 individuals enrolled in the U.K. Prospective Diabetes Study (UKPDS) without PVD at diagnosis of diabetes, followed for 6 years, and for whom relevant data were available. PVD was defined as two of the following: ankle-arm blood pressure index < 0.8, absence of both dorsalis pedis and posterior tibial pulses to palpation in one or both legs, and intermittent claudication. Logistic regression was used to estimate the association between potential risk factors measured 3-4 months after diagnosis of diabetes and incident PVD. The prevalence of PVD at 3-year intervals to 18 years was determined. RESULTS: Hyperglycemia, assessed as HbA(1c), was associated with an increased risk for incident PVD, independent of other risk factors including age, increased systolic blood pressure, reduced HDL cholesterol, smoking, prior cardiovascular disease, peripheral sensory neuropathy, and retinopathy. Each 1% increase in HbA(1c) was associated with a 28% increased risk of PVD (95% CI 12-46), and each 10-mmHg increase in systolic blood pressure with a 25% increase in risk (95% CI 10-43). CONCLUSIONS: Hyperglycemia, as well as smoking, dyslipidemia, and blood pressure are potentially modifiable risk factors for the development of PVD.  相似文献   
99.

Background

Literature indicates a relationship between selenium supplementation and risk of diabetes. However, because these data are inconclusive, we investigated the effect of selenium supplementation on serum glucose levels in men with prostate cancer enrolled in a clinical trial testing of the effect of selenium on prostate cancer progression.

Methods

Subjects were randomized to receive placebo (n = 46), selenium 200 μg/day (n = 47), and selenium 800 μg/day (n = 47). Serum glucose levels were obtained every 6 months for up to 5 years. Longitudinal analysis was carried out to assess whether rate of change of serum glucose levels was significantly different in the selenium-supplemented groups as compared with placebo. Sensitivity analyses were performed to assess the robustness of findings.

Results

Changes in serum glucose levels during the course of the trial were not statistically significantly different as compared with placebo for the selenium 200 μg/day (P = .56) or selenium 800 μg/day (P = .91) treatment groups.

Conclusion

These results do not support a relationship between selenium supplementation and changes in serum glucose levels. Recommendations about selenium supplementation and risk of diabetes will require more definitive studies.  相似文献   
100.
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