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101.
A case of mycosis fungoides in which pathologic rupture of the spleen led to intraperitoneal hemorrhage and death is described. To our knowledge, splenic rupture has not been reported previously as a cause of death in mycosis fungoides. Immunologic studies demonstrated that the neoplastic cell was a suppressor/cytotoxic T-cell. In most cases of mycosis fungoides or the Sézary syndrome, the neoplastic cell has been a helper/inducer T-cell. This case was very aggressive clinically with prominent visceral involvement and suggests that mycosis fungoides may be clinically diverse as well as immunologically heterogeneous.  相似文献   
102.
Development of the rete ovarii and its contribution to the cells of the ovary were examined in fetal rats. Histochemical and autoradiographic techniques were used for the observations between days 15 and 21 of gestation. The data presented indicate that the rete system contributes somatic cells to the ovary before birth. The basement membrane which surrounds the cuboidal epithelium of the mesonephric tubules immediately adjacent to the ovary becomes discontinuous on day 15 of gestation. The mesonephric epithelial cells in this region form a knot or clump of pleiomorphic cells, with no apparent tubular organization, and this clump later becomes surrounded by a basement membrane. On day 17 of gestation the newly established fetal rete ovarii is comprised of three regions; (1) the extraovarian mesonephric tubules (ER), (2) intraovarian cords of flattened epithelioid cells which surround the oogonia (IR), and (3) a knot or clump of cells connecting the ER and IR regions (CR). The entire rete system is enclosed by a continuous basement membrane as defined by Periodic Acid-Schiff Reagent techniques. Autoradiographic and quantitative analyses demonstrate that the ER tubule cells proliferate and are incorporated into the other regions of the rete system. These processes begin on day 17 and continue until at least day 21 of gestation. The role these mesonephric tubule cells may play in the regulation of meiosis and their early contribution to the presumptive granulosa cell population is discussed.  相似文献   
103.
Adult, male hooded rats were tested on a six-choice jumping stand apparatus designed to study their ability to perform visually guided orientation movements with a brightness discrimination task. Upon reaching criterion, the rats suffered either one- or two-stage, bilateral electrolytic lesions of the superior colliculi and then, after a brief recovery period, were retested for their ability to retain the preoperatively learned task and, in addition, perform a more difficult task. Although both brain damaged groups evidenced an impairment in comparison to sham-operated controls, the rats with two-stage lesions were less disabled than their simultaneously operated counterparts.  相似文献   
104.
105.
Marginal zone B-cell lymphomas (MCL) of extranodal, nodal and splenic origin appear to be different lymphoma entities with a similar growth pattern in the marginal zone of the B-follicles. Decisive for the detection of MCL as a distinct lymphoma entity was the "MALT concept" for lymphoid infiltrates in the gastric and intestinal mucosa as described by Isaacson et al. in the 1980's. Immunohistological stainings for the immunoglobulin light and heavy chains and molecular pathological studies of the immunoglobulin heavy chain gene configuration have subsequently confirmed the neoplastic nature of the extranodal infiltrates and differentiated marginal zone cells from mantle zone cells. In 1994, the MCL of MALT type as well as of nodal and splenic origin were included in the REAL classification and in 1998 in the new WHO classification for lymphomas. Meanwhile extranodal MCL of MALT-type have been observed in almost every organ and site of the body, by far most frequently in the gastric mucosa. Beside the typical growth pattern, lymphoepithelial lesions are a distinct diagnostic feature of extranodal MCL. Clinically, the small cell extranodal MCL show a very good prognosis with regression after treatment. As for nodal and splenic MCL, we need further studies to evaluate the prognostic aspects and to compare them with other B-cell lymphomas. The same is true for primary extranodal large B-cell lymphomas or blastic transformation to a large cell lymphoma; in these tumors the diagnosis of a MALT type lymphoma should only be made if a small cell component with MALT-specific criteria can be proved.  相似文献   
106.
OBJECTIVE: Gynecologic disease is common in HIV-infected women. We examine the sociodemographic, clinical, and provider factors associated with the care of women with vaginal symptoms. METHODS: Women enrolled in the HIV Cost and Services Utilization Study (HCSUS), a nationally representative probability sample of HIV-infected adults, were interviewed between January 1996 and April 1997. Women with vaginal symptoms who sought medical attention were asked, "Did your health care provider examine your vaginal area?" Women were also asked if they received medication for their symptoms. RESULTS: Among 154 women with vaginal symptoms, 127 sought care for their symptoms. Of those who sought care, 48% saw a gynecologist and 52% sought care from nongynecologists, most often their usual HIV care provider. Women who saw a gynecologist for their symptoms were more likely to have received a pelvic examination (92% versus 76%; p =.06) and vaginal fluid collection (98% versus 88%; p =.06) than those who saw their regular HIV provider. Fifteen percent of women received medication for their symptoms without having a pelvic examination; gynecologists were less likely to prescribe without an examination (8% versus 21%; p =.12). CONCLUSION: Gynecologists are more likely to provide adequate care of vaginal symptoms among HIV-infected women than nongynecologists who were HIV care providers. This specialty difference is consistent with quality of care studies for other medical conditions, but the potential gynecologic complications of inadequate evaluation and treatment warrants further investigation.  相似文献   
107.
Twenty-eight cases of cutaneous T cell lymphomas of mycosis fungoides type, 8 of which showed a marked epidermotropism, were investigated for their reactivity with the monoclonal antibody HML-1. This reagent selectively recognizes human benign and malignant intestinal T lymphocytes, but not benign or malignant lymph node T cells. In all cases, the majority of nonepithelium-associated T cells present in the corium were HML-1 negative. In the eight cases with marked epidermotropism, the intraepidermal (IED) T cells were HML-1 positive in three cases, and HML-1 negative in the remaining five cases. The HML-1 positive IED T cells tended to be localized preferentially in the basal layers, whereas the HML-1 negative IED T cells were more diffusely distributed throughout all epidermal cell layers or formed intra-epidermal aggregates. These findings provide further evidence that mycosis fungoides is not a single entity, but represents a group of neoplasms originating from different T cell subsets that have in common their tropism to epidermis and/or dermis, and thus have a similar clinical presentation.  相似文献   
108.
Polypoid tumor of the esophagus   总被引:2,自引:0,他引:2  
Five cases of an uncommon esophageal tumor consisting of a mucosal squamous cell carcinoma that surrounds a polypoid mass of spindle cells were examined. The spindle cell component was composed of elongated cells with blunt nuclei, admixed with multinucleated giant cells. Reticulin fibers enveloped individual cells, and abundant collagen was present. Thirteen to 69 mitotic figures occurred per 10 high-power fields. Electron microscopy showed dilated cisternae of rough endoplasmic reticulum and peripheral intermediate filaments within the cytoplasm. Intermediate-type junctions (zonulae adherens) and subplasmalemmal linear densities connected some cells. No tonofibrillar bundles or desmosomes (maculae adherens) were present. Immunoperoxidase stains detected no keratin in the spindle cells. Alpha-1-antichymotrypsin and alpha-1-antitrypsin were in the spindle cells in five of five and three of five cases, respectively. The absence of desmosomes, tonofibrillar bundles, and keratin and the presence of alpha-1-antitrypsin and alpha-1-antichymotrypsin favor fibrohistiocytic differentiation of the spindle cell component.  相似文献   
109.
We report on three patients with Costello syndrome and isolated growth hormone (GH) deficiency treated with biosynthetic GH. To our knowledge, these are the only patients with Costello syndrome who have been successfully treated for GH deficiency. We review the pathophysiology of Costello syndrome and highlight the recent recommendations of tumor screening and cardiac surveillance in this population, of particular relevance to those receiving GH therapy.  相似文献   
110.
BACKGROUND: The knowledge available on electroconvulsive therapy (ECT) in adolescents is largely anecdotal, or based on findings from adults. The aim of the present study is to compare the use of ECT in adolescent and adult inpatients. METHODS: We retrospectively analyzed the files of all 36 adolescent (between the ages of 13 and 19) and 57 randomly selected adult inpatients (above the age of 20) treated with ECT in a university-affiliated mental heath center in Israel between 1991 and 1997. RESULTS: Sixty one percent of the adolescents improved by the end of treatment, and 53% were not hospitalized in the subsequent year. The respective percentages among adults were 83% and 49%. Whereas most adults were treated with ECT because of schizophrenic disorders, almost half of the adolescents received ECT for affective disorders. Significantly more adolescents were treated with ECT because of acute life-endangering conditions (catatonia or severe suicidal risk). No significant adverse effects were found in both groups. LIMITATIONS: Our study is based on a retrospective chart review. The adolescent and adult groups are different in psychiatric morbidity, diagnosis and outcome, have not been assessed in a blind manner, and we have not used standardized psychometric batteries for the evaluation of ECT-related memory disturbances. CONCLUSIONS: ECT may be an effective, well-tolerated and safe procedure in both adult and adolescent inpatients.  相似文献   
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