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81.
Anaerobic characteristics in male children and adolescents   总被引:4,自引:0,他引:4  
Only sparse information has been published on the effects of growth, development, and maturation on the ability to perform high intensity, short-term "anaerobic" tasks. Cross-sectional studies on Italian, African, British, and American females and males have indicated an age-related progression in the performance of the Margaria step-running test. Children had a distinctly lower mechanical power output than adolescents and young adults, both in absolute terms and when divided by body weight, or by fat-free mass. Data are presented on some 300 10- to 45-yr-old Israeli males who performed the Wingate anaerobic test by cycling or by arm cranking. Both the peak power at any 5-s period and the mean power throughout the test were lowest in the children, whether expressed in absolute power units or corrected for body weight. Performance progressed with age and reached the highest values at the end of the third decade for cycling and at the end of the second decade for arm cranking. This pattern is unlike that described for maximal O2 uptake per kg body weight which, in males, remains virtually unchanged from childhood to young adulthood. In females, maximal O2 uptake per kg is even higher in children than among adolescents or adults. Biochemical correlates of such a low anaerobic performance in children are their lower maximal lactate concentration in muscle and blood, lower rate of anaerobic glycolysis, and lower levels of acidosis at maximal exercise. The mechanisms for the relatively deficient anaerobic characteristics of children are not clear.  相似文献   
82.
Kaposi''s sarcoma is a rare neoplasm of characteristic chronicity. The classical form which occurs most often in elderly men of Eastern European origin, comprises both an indolent, cutaneous type marked by spontaneous regression with prolonged survival, and a rarer, disseminated variant is more fulminant. Seven elderly Jewish patients with classical, disseminated, visceral Kaposi''s sarcoma were studied; they were neither homosexual nor drug-abusers. All immunologic parameters were normal and serum tests for HIV antibodies, CMV, and EBV were negative. Five of these patients were treated and four responded well, including two complete remissions. The prolonged survival of these patients (82% at 5 years) suggests the existence of an indolent subtype or forme fruste of the usually aggressive form of classical Kaposi''s sarcoma.  相似文献   
83.
Human interleukin-3-like activity (IL-3-LA), a factor possessing similar characteristics to interleukin-3 and having clony stimulating factor (CSF) activity, has recently been defined. In the present study, IL-3-LA levels in the sera of women before and after delivery were examined. The results indicate a significant increase in IL-3-LA levels in women before delivery as compared to IL-3-LA levels after delivery or to non-pregnant healthy women. The ability of mononuclear cells from women before and after delivery to produce IL-3-LA was similar to that of mononuclear cells from cord blood. In addition, the effect of progesterone on in vitro IL-3-LA production was examined and a stimulatory dose-dependent effect was observed. These observations point to the hypothesis that during pregnancy IL-3-LA levels are modulated by progesterone. With placental loss, the IL-3-LA in the sera decreases, although the mononuclear cells previously affected by the hormone continue to produce cytokines.  相似文献   
84.
Adjuvant chemotherapy in colorectal cancer patients is aimed at decreasing the relapse rate of the disease and increasing the disease-free and the overall survival of the patients. In a prospective study we evaluated the efficacy of 5-FU plus levamisole as an aduvant therapy for 153 patients with Dukes' B-2 or C colon or rectal cancer following a curative-intended surgery. Adjuvant chemotherapy was started within 4 to 6 weeks following the operation. Combination of 5-FU 375 mg/m(2)/day was given intravenously over 15-20 min for 5 consecutive days, every month for 1 year. Levamisole 50 mg t.i.d. was administered orally during the first 3 days of each course of chemotherapy. Rectal cancer patients were also irradiated to the tumor bed and pelvic lymphatics. The dose intensities (DI) of 5-FU and levamisole in our study were 432.6 mg/m(2)/w and 103.8 mg/m(2)/w, respectively. Failure analysis in Dukes' B and C patients showed that the rectum accounted for 47.5% of the relapses, of which only 3 cases were in the vicinity of the resected area. Almost half of the failures were observed within the year of adjuvant treatment. The liver was the most common site for first relapse (50%). The 3-year disease-free survival of Dukes' B-2 patients group was 84%, compared with 64% in Dukes' C. The main toxic manifestations were diarrhea, nausea and vomiting, weakness and mucositis. No dose reduction was needed. Our protocol, using lower DI of levamisole yielded similar results with a lower rate of toxicity than other common protocols.  相似文献   
85.
Two biopsies of intraductal and invasive lobular carcinoma of the breast and 11 biopsies of intraductal and invasive carcinoma of the breast were examined by automated micromensurative techniques for mean nuclear area of carcinoma cells in intraductal and in invasive compartments. The nuclei of invasive carcinoma cells tended to be smaller when they invaded stroma as single cells or as "thin strands" than when they invaded as part of large sheets of cells. Cells in direct apposition with the stroma usually had smaller nuclei than cells which were found centrally in large confluent sheets of cells. Intraduct carcinoma cells approached, in size, invasive cells which formed confluent sheets, rather than cancer cells which invaded as single cells. The nuclei of cells which invaded in small groups were usually darker than those of cells in confluent sheets, which were usually more vesicular.  相似文献   
86.
Mapping average axon diameter (AAD) and axon diameter distribution (ADD) in neuronal tissues non‐invasively is a challenging task that may have a tremendous effect on our understanding of the normal and diseased central nervous system (CNS). Water diffusion is used to probe microstructure in neuronal tissues, however, the different water populations and barriers that are present in these tissues turn this into a complex task. Therefore, it is not surprising that recently we have witnessed a burst in the development of new approaches and models that attempt to obtain, non‐invasively, detailed microstructural information in the CNS. In this work, we aim at challenging and comparing the microstructural information obtained from single diffusion encoding (SDE) with double diffusion encoding (DDE) MRI. We first applied SDE and DDE MR spectroscopy (MRS) on microcapillary phantoms and then applied SDE and DDE MRI on an ex vivo porcine spinal cord (SC), using similar experimental conditions. The obtained diffusion MRI data were fitted by the same theoretical model, assuming that the signal in every voxel can be approximated as the superposition of a Gaussian‐diffusing component and a series of restricted components having infinite cylindrical geometries. The diffusion MRI results were then compared with histological findings. We found a good agreement between the fittings and the experimental data in white matter (WM) voxels of the SC in both diffusion MRI methods. The microstructural information and apparent AADs extracted from SDE MRI were found to be similar or somewhat larger than those extracted from DDE MRI especially when the diffusion time was set to 40 ms. The apparent ADDs extracted from SDE and DDE MRI show reasonable agreement but somewhat weaker correspondence was observed between the diffusion MRI results and histology. The apparent subtle differences between the microstructural information obtained from SDE and DDE MRI are briefly discussed.  相似文献   
87.
Although sexuality is an important part of health and emotional well-being throughout the entire life cycle, including during old age, little is known about how physicians discuss or approach the topic of sexuality during later life. The present study examined the perspectives of two groups of physicians toward discussing sexuality with older patients: 17 physicians who did not have any training in human sexuality and 21 physicians who were certified as sex therapists. The interviews underwent thematic content analysis to identify and code major themes and patterns. Qualitative analysis of the interviews yielded three main themes: (a) discourse between physicians and older adults regarding sexuality, (b) diagnosing sexual dysfunction among older adults, and (c) treating sexual dysfunction among older adults. Physicians who were not trained in sex therapy did not regularly ask their older patients about sexual functioning and/or problems with sex, tended to diagnose sexual problems from a medical perspective, and offered medication as the main treatment for sexual problems. Physicians trained as sex therapists felt more comfortable discussing sex-related issues with their older patients and diagnosed sexual problems from a medical, social, dyadic and psychological perspective. Although they offered their older patients a greater variety of medication-oriented interventions than those without training in sexuality, they did not rush into such interventions and instead emphasised the importance of the psychological and relational aspects of sex. The present study highlights the importance of human sexuality training for physicians and points out the effects of such training on the discourse, diagnosis and treatment of sexual concerns in later life.  相似文献   
88.
89.

Background

Hypothyroidism is prevalent in morbidly obese patients and may improve after a weight reduction surgery.

Objectives

Laboratory and clinical changes in hypothyroid patients undergoing laparoscopic sleeve gastrectomy (LSG) or laparoscopic Roux-en-Y gastric bypass (LRYGB) were compared and evaluated.

Settings

Data were retrieved from a prospectively collected database of 2 public bariatric units.

Methods

Patients with hypothyroidism prior to bariatric procedure were evaluated for changes in thyroid stimulating hormone (TSH) and changes or cessation of hormone replacement therapy after surgery. Correlation between changes in TSH levels and percentage of excess weight loss and comparison between effects of LSG and LRYGB were evaluated.

Results

Ninety patients were included. Mean follow-up was 11 ± 9 .73 months. Mean body mass index decreased from 43.8 to 33.2 kg/m2. Forty patients had deranged elevated TSH levels prior to surgery that decreased significantly after surgery (mean 6.6 ± 1.9 to 2.9 ± 1.5 mU/L, P < .01). Of patients receiving hormone replacement therapy prior to surgery, 42% required lower doses, with a 61% mean decrease in doses, while 10% stopped hormone replacement therapy completely. No correlation was found between the improvement in TSH and percentage of excess weight loss. A significant advantage to one of the bariatric procedures (LSG [61] and LRYGB [29]) could not be established.

Conclusions

LSG and LRYGB both proved to improve thyroid function in hypothyroid obese patients. No procedure was found to be superior. No correlation was found between percentage of excess weight loss and TSH reduction. This implies that the effect of bariatric surgery on the improvement of thyroid functions is mediated by mechanisms other than weight loss, probably hormonal.  相似文献   
90.
Clones (D(+)) of a cultured line of myeloid leukemic cells can be induced to undergo normal differentiation to mature macrophages and granulocytes. There are also clones derived from the same cell line (D(-)) that could not be induced to differentiate. The carbohydrate-binding protein concanavalin A was used as a probe to study the mobility of carbohydrate-containing sites on the surface membrane of these cells. Changes in the distribution of concanavalin A binding sites on the surface membrane can be induced by concanavalin A. With the appropriate site mobility, this induction of a new distribution resulted in a concentration of concanavalin A-membrane site complexes on one pole of the cell to form a cap. D(+) and D(-) clones showed 50 and 5% of cells with caps, respectively, although both types of cells bound a similar number of concanavalin A molecules. Treatment of cells with trypsin increased cap formation from 5 to 40% in D(-) cells, but did not change the percentage of cells with caps in D(+) cells. The results show a difference in the mobility of concanavalin A binding sites in these two types of cells and suggest a difference in the fluid state of these carbohydrate-containing structures on the surface membrane. It is suggested that a gain of the ability of myeloid leukemic cells to undergo normal differentiation is associated with an increase in the fluidity of structures on the surface membrane where the concanavalin A sites are located. Differences in fluidity of specific membrane sites may also explain differences in the response of cells to other differentiation-inducing stimuli.  相似文献   
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